A group of genetic, infectious, or sporadic degenerative human and animal nervous system disorders associated with abnormal PRIONS. These diseases are characterized by conversion of the normal prion protein to an abnormal configuration via a post-translational process. In humans, these conditions generally feature DEMENTIA; ATAXIA; and a fatal outcome. Pathologic features include a spongiform encephalopathy without evidence of inflammation. The older literature occasionally refers to these as unconventional SLOW VIRUS DISEASES. (From Proc Natl Acad Sci USA 1998 Nov 10;95(23):13363-83)
Abnormal isoform of prion proteins (PRIONS) resulting from a posttranslational modification of the cellular prion protein (PRPC PROTEINS). PrPSc are disease-specific proteins seen in certain human and animal neurodegenerative diseases (PRION DISEASES).
A fatal disease of the nervous system in sheep and goats, characterized by pruritus, debility, and locomotor incoordination. It is caused by proteinaceous infectious particles called PRIONS.
Proteins that are involved in the peptide chain termination reaction (PEPTIDE CHAIN TERMINATION, TRANSLATIONAL) on RIBOSOMES. They include codon-specific class-I release factors, which recognize stop signals (TERMINATOR CODON) in the MESSENGER RNA; and codon-nonspecific class-II release factors.
A transmissible spongiform encephalopathy (prion disease) of DEER and elk characterized by chronic weight loss leading to death. It is thought to spread by direct contact between animals or through environmental contamination with the prion protein (PRIONS).
Normal cellular isoform of prion proteins (PRIONS) encoded by a chromosomal gene and found in normal and scrapie-infected brain tissue, and other normal tissue. PrPC are protease-sensitive proteins whose function is unknown. Posttranslational modification of PrPC into PrPSC leads to infectivity.
A rare transmissible encephalopathy most prevalent between the ages of 50 and 70 years. Affected individuals may present with sleep disturbances, personality changes, ATAXIA; APHASIA, visual loss, weakness, muscle atrophy, MYOCLONUS, progressive dementia, and death within one year of disease onset. A familial form exhibiting autosomal dominant inheritance and a new variant CJD (potentially associated with ENCEPHALOPATHY, BOVINE SPONGIFORM) have been described. Pathological features include prominent cerebellar and cerebral cortical spongiform degeneration and the presence of PRIONS. (From N Engl J Med, 1998 Dec 31;339(27))
A genus of ascomycete FUNGI in the order SORDARIALES, which is found on SOIL and herbivore dung (FECES).
A transmissible spongiform encephalopathy of cattle associated with abnormal prion proteins in the brain. Affected animals develop excitability and salivation followed by ATAXIA. This disorder has been associated with consumption of SCRAPIE infected ruminant derived protein. This condition may be transmitted to humans, where it is referred to as variant or new variant CREUTZFELDT-JAKOB SYNDROME. (Vet Rec 1998 Jul 25;143(41):101-5)
A fibrous protein complex that consists of proteins folded into a specific cross beta-pleated sheet structure. This fibrillar structure has been found as an alternative folding pattern for a variety of functional proteins. Deposits of amyloid in the form of AMYLOID PLAQUES are associated with a variety of degenerative diseases. The amyloid structure has also been found in a number of functional proteins that are unrelated to disease.
The family Cervidae of 17 genera and 45 species occurring nearly throughout North America, South America, and Eurasia, on most associated continental islands, and in northern Africa. Wild populations of deer have been established through introduction by people in Cuba, New Guinea, Australia, New Zealand, and other places where the family does not naturally occur. They are slim, long-legged and best characterized by the presence of antlers. Their habitat is forests, swamps, brush country, deserts, and arctic tundra. They are usually good swimmers; some migrate seasonally. (Walker's Mammals of the World, 5th ed, p1362)
A genus of the family Muridae having three species. The present domesticated strains were developed from individuals brought from Syria. They are widely used in biomedical research.
The amount time between exposure to an infectious agent and becoming symptomatic.
Laboratory mice that have been produced from a genetically manipulated EGG or EMBRYO, MAMMALIAN.
The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.
A colloidal, hydrated aluminum silicate that swells 12 times its dry size when added to water.
An enzyme that catalyzes the hydrolysis of keratin, and of other proteins with subtilisin-like specificity. It hydrolyses peptide amides. Endopeptidase K is from the mold Tritirachium album Limber. (Enzyme Nomenclature, 1992) EC
Tungsten hydroxide oxide phosphate. A white or slightly yellowish-green, slightly efflorescent crystal or crystalline powder. It is used as a reagent for alkaloids and many other nitrogen bases, for phenols, albumin, peptone, amino acids, uric acid, urea, blood, and carbohydrates. (From Merck Index, 11th ed)
Proteins obtained from the species SACCHAROMYCES CEREVISIAE. The function of specific proteins from this organism are the subject of intense scientific interest and have been used to derive basic understanding of the functioning similar proteins in higher eukaryotes.
A subfamily in the family MURIDAE, comprising the hamsters. Four of the more common genera are Cricetus, CRICETULUS; MESOCRICETUS; and PHODOPUS.
Processes involved in the formation of TERTIARY PROTEIN STRUCTURE.
A suborder of the order ARTIODACTYLA whose members have the distinguishing feature of a four-chambered stomach, including the capacious RUMEN. Horns or antlers are usually present, at least in males.
Any of the ruminant mammals with curved horns in the genus Ovis, family Bovidae. They possess lachrymal grooves and interdigital glands, which are absent in GOATS.
A species of the genus SACCHAROMYCES, family Saccharomycetaceae, order Saccharomycetales, known as "baker's" or "brewer's" yeast. The dried form is used as a dietary supplement.
An indolizidine alkaloid from the plant Swainsona canescens that is a potent alpha-mannosidase inhibitor. Swainsonine also exhibits antimetastatic, antiproliferative, and immunomodulatory activity.
A prion disease found exclusively among the Fore linguistic group natives of the highlands of NEW GUINEA. The illness is primarily restricted to adult females and children of both sexes. It is marked by the subacute onset of tremor and ataxia followed by motor weakness and incontinence. Death occurs within 3-6 months of disease onset. The condition is associated with ritual cannibalism, and has become rare since this practice has been discontinued. Pathologic features include a noninflammatory loss of neurons that is most prominent in the cerebellum, glial proliferation, and amyloid plaques. (From Adams et al., Principles of Neurology, 6th ed, p773)
A method of measuring the effects of a biologically active substance using an intermediate in vivo or in vitro tissue or cell model under controlled conditions. It includes virulence studies in animal fetuses in utero, mouse convulsion bioassay of insulin, quantitation of tumor-initiator systems in mouse skin, calculation of potentiating effects of a hormonal factor in an isolated strip of contracting stomach muscle, etc.
The restriction of a characteristic behavior, anatomical structure or physical system, such as immune response; metabolic response, or gene or gene variant to the members of one species. It refers to that property which differentiates one species from another but it is also used for phylogenetic levels higher or lower than the species.
Changes in the amounts of various chemicals (neurotransmitters, receptors, enzymes, and other metabolites) specific to the area of the central nervous system contained within the head. These are monitored over time, during sensory stimulation, or under different disease states.
An order of fungi in the phylum ASCOMYCOTA that includes many valuable experimental organisms. There are eight families and very few anamorphic forms.
Proteins which are synthesized in eukaryotic organisms and bacteria in response to hyperthermia and other environmental stresses. They increase thermal tolerance and perform functions essential to cell survival under these conditions.
The unconsolidated mineral or organic matter on the surface of the earth that serves as a natural medium for the growth of land plants.
Non-hematopoietic cells, with extensive dendritic processes, found in the primary and secondary follicles of lymphoid tissue (the B cell zones). They are different from conventional DENDRITIC CELLS associated with T-CELLS. They are derived from MESENCHYMAL STEM CELLS and are negative for class II MHC antigen and do not process or present antigen like the conventional dendritic cells do. Instead, follicular dendritic cells have FC RECEPTORS and C3B RECEPTORS that hold antigen in the form of ANTIGEN-ANTIBODY COMPLEXES on their surfaces for long periods for recognition by B-CELLS.
A tough, malleable, iron-based alloy containing up to, but no more than, two percent carbon and often other metals. It is used in medicine and dentistry in implants and instrumentation.
The transmission of infectious disease or pathogens. When transmission is within the same species, the mode can be horizontal or vertical (INFECTIOUS DISEASE TRANSMISSION, VERTICAL).
An autosomal dominant familial prion disease with a wide spectrum of clinical presentations including ATAXIA, spastic paraparesis, extrapyramidal signs, and DEMENTIA. Clinical onset is in the third to sixth decade of life and the mean duration of illness prior to death is five years. Several kindreds with variable clinical and pathologic features have been described. Pathologic features include cerebral prion protein amyloidosis, and spongiform or neurofibrillary degeneration. (From Brain Pathol 1998 Jul;8(3):499-513; Brain Pathol 1995 Jan;5(1):61-75)
The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).
Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.
A family of heat-shock proteins that contain a 70 amino-acid consensus sequence known as the J domain. The J domain of HSP40 heat shock proteins interacts with HSP70 HEAT-SHOCK PROTEINS. HSP40 heat-shock proteins play a role in regulating the ADENOSINE TRIPHOSPHATASES activity of HSP70 heat-shock proteins.
The removal of contaminating material, such as radioactive materials, biological materials, or CHEMICAL WARFARE AGENTS, from a person or object.
Proteins found in any species of fungus.
Rendering pathogens harmless through the use of heat, antiseptics, antibacterial agents, etc.
An acridine derivative formerly widely used as an antimalarial but superseded by chloroquine in recent years. It has also been used as an anthelmintic and in the treatment of giardiasis and malignant effusions. It is used in cell biological experiments as an inhibitor of phospholipase A2.
Any of the numerous types of clay which contain varying proportions of Al2O3 and SiO2. They are made synthetically by heating aluminum fluoride at 1000-2000 degrees C with silica and water vapor. (From Hawley's Condensed Chemical Dictionary, 11th ed)
A general term for single-celled rounded fungi that reproduce by budding. Brewers' and bakers' yeasts are SACCHAROMYCES CEREVISIAE; therapeutic dried yeast is YEAST, DRIED.
Proteins that form the core of amyloid fibrils. For example, the core of amyloid A is formed from amyloid A protein, also known as serum amyloid A protein or SAA protein.
Disorders caused by imbalances in the protein homeostasis network - synthesis, folding, and transport of proteins; post-translational modifications; and degradation or clearance of misfolded proteins.
Preparations made from animal tissues or organs (ANIMAL STRUCTURES). They usually contain many components, any one of which may be pharmacologically or physiologically active. Tissue extracts may contain specific, but uncharacterized factors or proteins with specific actions.
Accumulations of extracellularly deposited AMYLOID FIBRILS within tissues.
Common name for the largest birds in the order PASSERIFORMES, family Corvidae. These omnivorous black birds comprise most of the species in the genus Corvus, along with ravens and jackdaws (which are often also referred to as crows).
A family of cellular proteins that mediate the correct assembly or disassembly of polypeptides and their associated ligands. Although they take part in the assembly process, molecular chaperones are not components of the final structures.
A strong organic base existing primarily as guanidium ions at physiological pH. It is found in the urine as a normal product of protein metabolism. It is also used in laboratory research as a protein denaturant. (From Martindale, the Extra Pharmacopoeia, 30th ed and Merck Index, 12th ed) It is also used in the treatment of myasthenia and as a fluorescent probe in HPLC.
The level of protein structure in which combinations of secondary protein structures (alpha helices, beta sheets, loop regions, and motifs) pack together to form folded shapes called domains. Disulfide bridges between cysteines in two different parts of the polypeptide chain along with other interactions between the chains play a role in the formation and stabilization of tertiary structure. Small proteins usually consist of only one domain but larger proteins may contain a number of domains connected by segments of polypeptide chain which lack regular secondary structure.
An anionic surfactant, usually a mixture of sodium alkyl sulfates, mainly the lauryl; lowers surface tension of aqueous solutions; used as fat emulsifier, wetting agent, detergent in cosmetics, pharmaceuticals and toothpastes; also as research tool in protein biochemistry.
A class of MOLECULAR CHAPERONES found in both prokaryotes and in several compartments of eukaryotic cells. These proteins can interact with polypeptides during a variety of assembly processes in such a way as to prevent the formation of nonfunctional structures.
A system of organs and tissues that process and transport immune cells and LYMPH.
The characteristic 3-dimensional shape and arrangement of multimeric proteins (aggregates of more than one polypeptide chain).
The level of protein structure in which regular hydrogen-bond interactions within contiguous stretches of polypeptide chain give rise to alpha helices, beta strands (which align to form beta sheets) or other types of coils. This is the first folding level of protein conformation.
Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.
Protease-resistant core of PrPSC, the abnormal isoform of prion proteins (PRIONS). PrP 27-30 is produced by limited proteolysis of the N-terminus of PrPSc.
Any adverse condition in a patient occurring as the result of treatment by a physician, surgeon, or other health professional, especially infections acquired by a patient during the course of treatment.
A constitution or condition of the body which makes the tissues react in special ways to certain extrinsic stimuli and thus tends to make the individual more than usually susceptible to certain diseases.
A non-essential amino acid that is involved in the metabolic control of cell functions in nerve and brain tissue. It is biosynthesized from ASPARTIC ACID and AMMONIA by asparagine synthetase. (From Concise Encyclopedia Biochemistry and Molecular Biology, 3rd ed)
A subfamily of MURIDAE found nearly world-wide and consisting of about 20 genera. Voles, lemmings, and muskrats are members.
Identification of proteins or peptides that have been electrophoretically separated by blot transferring from the electrophoresis gel to strips of nitrocellulose paper, followed by labeling with antibody probes.
Diseases of non-human animals that may be transmitted to HUMANS or may be transmitted from humans to non-human animals.
Hereditary and sporadic conditions which are characterized by progressive nervous system dysfunction. These disorders are often associated with atrophy of the affected central or peripheral nervous system structures.
The imide of phthalic acids.
Hand-held tools or implements used by health professionals for the performance of surgical tasks.
Animals considered to be wild or feral or not adapted for domestic use. It does not include wild animals in zoos for which ANIMALS, ZOO is available.
The properties of a pathogen that makes it capable of infecting one or more specific hosts. The pathogen can include PARASITES as well as VIRUSES; BACTERIA; FUNGI; or PLANTS.
Elements of limited time intervals, contributing to particular results or situations.
Disruption of the non-covalent bonds and/or disulfide bonds responsible for maintaining the three-dimensional shape and activity of the native protein.
The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.
The application of high intensity ultrasound to liquids.
The nervous system outside of the brain and spinal cord. The peripheral nervous system has autonomic and somatic divisions. The autonomic nervous system includes the enteric, parasympathetic, and sympathetic subdivisions. The somatic nervous system includes the cranial and spinal nerves and their ganglia and the peripheral sensory receptors.
The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
Naturally occurring or experimentally induced animal diseases with pathological processes sufficiently similar to those of human diseases. They are used as study models for human diseases.
Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.
A member of the tumor necrosis factor receptor superfamily. It has specificity for LYMPHOTOXIN ALPHA1, BETA2 HETEROTRIMER and TUMOR NECROSIS FACTOR LIGAND SUPERFAMILY MEMBER 14. The receptor plays a role in regulating lymphoid ORGANOGENESIS and the differentiation of certain subsets of NATURAL KILLER T-CELLS. Signaling of the receptor occurs through its association with TNF RECEPTOR-ASSOCIATED FACTORS.
The adhesion of gases, liquids, or dissolved solids onto a surface. It includes adsorptive phenomena of bacteria and viruses onto surfaces as well. ABSORPTION into the substance may follow but not necessarily.
Hydrolases that specifically cleave the peptide bonds found in PROTEINS and PEPTIDES. Examples of sub-subclasses for this group include EXOPEPTIDASES and ENDOPEPTIDASES.
Carnivores of genus Mustela of the family MUSTELIDAE. The European mink, which has white upper and lower lips, was widely trapped for commercial purposes and is classified as endangered. The American mink, lacking a white upper lip, is farmed commercially.
The ability of a protein to retain its structural conformation or its activity when subjected to physical or chemical manipulations.
Recombinant proteins produced by the GENETIC TRANSLATION of fused genes formed by the combination of NUCLEIC ACID REGULATORY SEQUENCES of one or more genes with the protein coding sequences of one or more genes.
The clear, viscous fluid secreted by the SALIVARY GLANDS and mucous glands of the mouth. It contains MUCINS, water, organic salts, and ptylin.
The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.
The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.
Specialized tissues that are components of the lymphatic system. They provide fixed locations within the body where a variety of LYMPHOCYTES can form, mature and multiply. The lymphoid tissues are connected by a network of LYMPHATIC VESSELS.
The functional hereditary units of FUNGI.
Diseases of domestic and mountain sheep of the genus Ovis.
Established cell cultures that have the potential to propagate indefinitely.
Warm-blooded vertebrate animals belonging to the class Mammalia, including all that possess hair and suckle their young.
A non-essential amino acid present abundantly throughout the body and is involved in many metabolic processes. It is synthesized from GLUTAMIC ACID and AMMONIA. It is the principal carrier of NITROGEN in the body and is an important energy source for many cells.
Substances used on inanimate objects that destroy harmful microorganisms or inhibit their activity. Disinfectants are classed as complete, destroying SPORES as well as vegetative forms of microorganisms, or incomplete, destroying only vegetative forms of the organisms. They are distinguished from ANTISEPTICS, which are local anti-infective agents used on humans and other animals. (From Hawley's Condensed Chemical Dictionary, 11th ed)
Animate or inanimate sources which normally harbor disease-causing organisms and thus serve as potential sources of disease outbreaks. Reservoirs are distinguished from vectors (DISEASE VECTORS) and carriers, which are agents of disease transmission rather than continuing sources of potential disease outbreaks.
Proteins prepared by recombinant DNA technology.
Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.
The presence in food of harmful, unpalatable, or otherwise objectionable foreign substances, e.g. chemicals, microorganisms or diluents, before, during, or after processing or storage.
Immunologic method used for detecting or quantifying immunoreactive substances. The substance is identified by first immobilizing it by blotting onto a membrane and then tagging it with labeled antibodies.
Histochemical localization of immunoreactive substances using labeled antibodies as reagents.
Establishment of the level of a quantifiable effect indicative of a biologic process. The evaluation is frequently to detect the degree of toxic or therapeutic effect.
Compounds containing carbohydrate or glycosyl groups linked to phosphatidylinositols. They anchor GPI-LINKED PROTEINS or polysaccharides to cell membranes.
A common neoplasm of early childhood arising from neural crest cells in the sympathetic nervous system, and characterized by diverse clinical behavior, ranging from spontaneous remission to rapid metastatic progression and death. This tumor is the most common intraabdominal malignancy of childhood, but it may also arise from thorax, neck, or rarely occur in the central nervous system. Histologic features include uniform round cells with hyperchromatic nuclei arranged in nests and separated by fibrovascular septa. Neuroblastomas may be associated with the opsoclonus-myoclonus syndrome. (From DeVita et al., Cancer: Principles and Practice of Oncology, 5th ed, pp2099-2101; Curr Opin Oncol 1998 Jan;10(1):43-51)
High molecular weight polymers containing a mixture of purine and pyrimidine nucleotides chained together by ribose or deoxyribose linkages.
Diseases that do not exhibit symptoms.
An encapsulated lymphatic organ through which venous blood filters.
Electron microscopy in which the ELECTRONS or their reaction products that pass down through the specimen are imaged below the plane of the specimen.
The nerves outside of the brain and spinal cord, including the autonomic, cranial, and spinal nerves. Peripheral nerves contain non-neuronal cells and connective tissue as well as axons. The connective tissue layers include, from the outside to the inside, the epineurium, the perineurium, and the endoneurium.
The main information-processing organs of the nervous system, consisting of the brain, spinal cord, and meninges.
The chemical or biochemical addition of carbohydrate or glycosyl groups to other chemicals, especially peptides or proteins. Glycosyl transferases are used in this biochemical reaction.
Different forms of a protein that may be produced from different GENES, or from the same gene by ALTERNATIVE SPLICING.
Proteins and peptides found in SALIVA and the SALIVARY GLANDS. Some salivary proteins such as ALPHA-AMYLASES are enzymes, but their composition varies in different individuals.
Strains of mice in which certain GENES of their GENOMES have been disrupted, or "knocked-out". To produce knockouts, using RECOMBINANT DNA technology, the normal DNA sequence of the gene being studied is altered to prevent synthesis of a normal gene product. Cloned cells in which this DNA alteration is successful are then injected into mouse EMBRYOS to produce chimeric mice. The chimeric mice are then bred to yield a strain in which all the cells of the mouse contain the disrupted gene. Knockout mice are used as EXPERIMENTAL ANIMAL MODELS for diseases (DISEASE MODELS, ANIMAL) and to clarify the functions of the genes.
Members of the class of compounds composed of AMINO ACIDS joined together by peptide bonds between adjacent amino acids into linear, branched or cyclical structures. OLIGOPEPTIDES are composed of approximately 2-12 amino acids. Polypeptides are composed of approximately 13 or more amino acids. PROTEINS are linear polypeptides that are normally synthesized on RIBOSOMES.
Diminished or failed response of an organism, disease or tissue to the intended effectiveness of a chemical or drug. It should be differentiated from DRUG TOLERANCE which is the progressive diminution of the susceptibility of a human or animal to the effects of a drug, as a result of continued administration.
A set of three nucleotides in a protein coding sequence that specifies individual amino acids or a termination signal (CODON, TERMINATOR). Most codons are universal, but some organisms do not produce the transfer RNAs (RNA, TRANSFER) complementary to all codons. These codons are referred to as unassigned codons (CODONS, NONSENSE).
Compounds formed by the joining of smaller, usually repeating, units linked by covalent bonds. These compounds often form large macromolecules (e.g., BIOPOLYMERS; PLASTICS).
The basic cellular units of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the NERVOUS SYSTEM.
The naturally occurring or experimentally induced replacement of one or more AMINO ACIDS in a protein with another. If a functionally equivalent amino acid is substituted, the protein may retain wild-type activity. Substitution may also diminish, enhance, or eliminate protein function. Experimentally induced substitution is often used to study enzyme activities and binding site properties.
Protein analogs and derivatives of the Aequorea victoria green fluorescent protein that emit light (FLUORESCENCE) when excited with ULTRAVIOLET RAYS. They are used in REPORTER GENES in doing GENETIC TECHNIQUES. Numerous mutants have been made to emit other colors or be sensitive to pH.
Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control of gene action in fungi.
The assembly of the QUATERNARY PROTEIN STRUCTURE of multimeric proteins (MULTIPROTEIN COMPLEXES) from their composite PROTEIN SUBUNITS.
Microscopy of specimens stained with fluorescent dye (usually fluorescein isothiocyanate) or of naturally fluorescent materials, which emit light when exposed to ultraviolet or blue light. Immunofluorescence microscopy utilizes antibodies that are labeled with fluorescent dye.
Transparent, tasteless crystals found in nature as agate, amethyst, chalcedony, cristobalite, flint, sand, QUARTZ, and tridymite. The compound is insoluble in water or acids except hydrofluoric acid.
Extrachromosomal, usually CIRCULAR DNA molecules that are self-replicating and transferable from one organism to another. They are found in a variety of bacterial, archaeal, fungal, algal, and plant species. They are used in GENETIC ENGINEERING as CLONING VECTORS.
Genes that are introduced into an organism using GENE TRANSFER TECHNIQUES.
Excrement from the INTESTINES, containing unabsorbed solids, waste products, secretions, and BACTERIA of the DIGESTIVE SYSTEM.
Loss of functional activity and trophic degeneration of nerve axons and their terminal arborizations following the destruction of their cells of origin or interruption of their continuity with these cells. The pathology is characteristic of neurodegenerative diseases. Often the process of nerve degeneration is studied in research on neuroanatomical localization and correlation of the neurophysiology of neural pathways.
Any spaces or cavities within a cell. They may function in digestion, storage, secretion, or excretion.
Procedures by which protein structure and function are changed or created in vitro by altering existing or synthesizing new structural genes that direct the synthesis of proteins with sought-after properties. Such procedures may include the design of MOLECULAR MODELS of proteins using COMPUTER GRAPHICS or other molecular modeling techniques; site-specific mutagenesis (MUTAGENESIS, SITE-SPECIFIC) of existing genes; and DIRECTED MOLECULAR EVOLUTION techniques to create new genes.
A type of scanning probe microscopy in which a probe systematically rides across the surface of a sample being scanned in a raster pattern. The vertical position is recorded as a spring attached to the probe rises and falls in response to peaks and valleys on the surface. These deflections produce a topographic map of the sample.
The genetic constitution of the individual, comprising the ALLELES present at each GENETIC LOCUS.
Change brought about to an organisms genetic composition by unidirectional transfer (TRANSFECTION; TRANSDUCTION, GENETIC; CONJUGATION, GENETIC, etc.) and incorporation of foreign DNA into prokaryotic or eukaryotic cells by recombination of part or all of that DNA into the cell's genome.
A genetic process by which the adult organism is realized via mechanisms that lead to the restriction in the possible fates of cells, eventually leading to their differentiated state. Mechanisms involved cause heritable changes to cells without changes to DNA sequence such as DNA METHYLATION; HISTONE modification; DNA REPLICATION TIMING; NUCLEOSOME positioning; and heterochromatization which result in selective gene expression or repression.
Techniques used for determining the values of photometric parameters of light resulting from LUMINESCENCE.
Characteristic restricted to a particular organ of the body, such as a cell type, metabolic response or expression of a particular protein or antigen.
Peptides generated from AMYLOID BETA-PEPTIDES PRECURSOR. An amyloid fibrillar form of these peptides is the major component of amyloid plaques found in individuals with Alzheimer's disease and in aged individuals with trisomy 21 (DOWN SYNDROME). The peptide is found predominantly in the nervous system, but there have been reports of its presence in non-neural tissue.
Partial proteins formed by partial hydrolysis of complete proteins or generated through PROTEIN ENGINEERING techniques.
A subclass of PEPTIDE HYDROLASES that catalyze the internal cleavage of PEPTIDES or PROTEINS.
The ability of a substance to be dissolved, i.e. to form a solution with another substance. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
A fractionated cell extract that maintains a biological function. A subcellular fraction isolated by ultracentrifugation or other separation techniques must first be isolated so that a process can be studied free from all of the complex side reactions that occur in a cell. The cell-free system is therefore widely used in cell biology. (From Alberts et al., Molecular Biology of the Cell, 2d ed, p166)
The phenotypic manifestation of a gene or genes by the processes of GENETIC TRANSCRIPTION and GENETIC TRANSLATION.
The rate dynamics in chemical or physical systems.
A group of enzymes which catalyze the hydrolysis of ATP. The hydrolysis reaction is usually coupled with another function such as transporting Ca(2+) across a membrane. These enzymes may be dependent on Ca(2+), Mg(2+), anions, H+, or DNA.
Accumulation of a drug or chemical substance in various organs (including those not relevant to its pharmacologic or therapeutic action). This distribution depends on the blood flow or perfusion rate of the organ, the ability of the drug to penetrate organ membranes, tissue specificity, protein binding. The distribution is usually expressed as tissue to plasma ratios.
The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH = log 1/2[1/(H+)], where (H+) is the hydrogen ion concentration in gram equivalents per liter of solution. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
Binary classification measures to assess test results. Sensitivity or recall rate is the proportion of true positives. Specificity is the probability of correctly determining the absence of a condition. (From Last, Dictionary of Epidemiology, 2d ed)
The process of moving proteins from one cellular compartment (including extracellular) to another by various sorting and transport mechanisms such as gated transport, protein translocation, and vesicular transport.
Genotypic differences observed among individuals in a population.
Differential and non-random reproduction of different genotypes, operating to alter the gene frequencies within a population.
The facilitation of a chemical reaction by material (catalyst) that is not consumed by the reaction.
Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations, or by parent x offspring matings carried out with certain restrictions. All animals within an inbred strain trace back to a common ancestor in the twentieth generation.
A degenerative disease of the BRAIN characterized by the insidious onset of DEMENTIA. Impairment of MEMORY, judgment, attention span, and problem solving skills are followed by severe APRAXIAS and a global loss of cognitive abilities. The condition primarily occurs after age 60, and is marked pathologically by severe cortical atrophy and the triad of SENILE PLAQUES; NEUROFIBRILLARY TANGLES; and NEUROPIL THREADS. (From Adams et al., Principles of Neurology, 6th ed, pp1049-57)
The arrangement of two or more amino acid or base sequences from an organism or organisms in such a way as to align areas of the sequences sharing common properties. The degree of relatedness or homology between the sequences is predicted computationally or statistically based on weights assigned to the elements aligned between the sequences. This in turn can serve as a potential indicator of the genetic relatedness between the organisms.
Variant forms of the same gene, occupying the same locus on homologous CHROMOSOMES, and governing the variants in production of the same gene product.
Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.
Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.
Endogenous substances, usually proteins, which are effective in the initiation, stimulation, or termination of the genetic transcription process.
Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.
Antibodies produced by a single clone of cells.
The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.
Filamentous proteins that are the main constituent of the thin filaments of muscle fibers. The filaments (known also as filamentous or F-actin) can be dissociated into their globular subunits; each subunit is composed of a single polypeptide 375 amino acids long. This is known as globular or G-actin. In conjunction with MYOSINS, actin is responsible for the contraction and relaxation of muscle.
The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.
An immunoassay utilizing an antibody labeled with an enzyme marker such as horseradish peroxidase. While either the enzyme or the antibody is bound to an immunosorbent substrate, they both retain their biologic activity; the change in enzyme activity as a result of the enzyme-antibody-antigen reaction is proportional to the concentration of the antigen and can be measured spectrophotometrically or with the naked eye. Many variations of the method have been developed.
The relationship between the dose of an administered drug and the response of the organism to the drug.
A latent susceptibility to disease at the genetic level, which may be activated under certain conditions.

Characterization of the interaction domains of Ure2p, a prion-like protein of yeast. (1/2897)

In the yeast Saccharomyces cerevisiae, the non-Mendelian inherited genetic element [URE3] behaves as a prion. A hypothesis has been put forward which states that [URE3] arises spontaneously from its cellular isoform Ure2p (the product of the URE2 gene), and propagates through interactions of the N-terminal domain of the protein, thus leading to its aggregation and loss of function. In the present study, various N- and C-terminal deletion mutants of Ure2p were constructed and their cross-interactions were tested in vitro and in vivo using affinity binding and a two-hybrid analysis. We show that the self-interaction of the protein is mediated by at least two domains, corresponding to the first third of the protein (the so-called prion-forming domain) and the C-terminal catalytic domain.  (+info)

Prion domain initiation of amyloid formation in vitro from native Ure2p. (2/2897)

The [URE3] non-Mendelian genetic element of Saccharomyces cerevisiae is an infectious protein (prion) form of Ure2p, a regulator of nitrogen catabolism. Here, synthetic Ure2p1-65 were shown to polymerize to form filaments 40 to 45 angstroms in diameter with more than 60 percent beta sheet. Ure2p1-65 specifically induced full-length native Ure2p to copolymerize under conditions where native Ure2p alone did not polymerize. Like Ure2p in extracts of [URE3] strains, these 180- to 220-angstrom-diameter filaments were protease resistant. The Ure2p1-65-Ure2p cofilaments could seed polymerization of native Ure2p to form thicker, less regular filaments. All filaments stained with Congo Red to produce the green birefringence typical of amyloid. This self-propagating amyloid formation can explain the properties of [URE3].  (+info)

A novel epitope for the specific detection of exogenous prion proteins in transgenic mice and transfected murine cell lines. (3/2897)

Prion diseases are closely linked to the conversion of host-encoded cellular prion protein (PrPC) into its pathological isoform (PrPSc). PrP conversion experiments in scrapie infected tissue culture cells, transgenic mice, and cell-free systems usually require unique epitopes and corresponding monoclonal antibodies (MAbs) for the immunological discrimination of exogenously introduced and endogenous PrP compounds (e.g., MAb 3F4, which is directed to an epitope on hamster and human but not on murine PrP). In the current work, we characterize a novel MAb designated L42 that reacts to PrP of a variety of species, including cattle, sheep, goat, dog, human, cat, mink, rabbit, and guinea pig, but does not bind to mouse, hamster, and rat PrP. Therefore, MAb L42 may allow future in vitro conversion and transgenic studies on PrPs of the former species. The MAb L42 epitope on PrPC includes a tyrosine residue at position 144, whereas mouse, rat, and hamster PrPs incorporate tryptophane at this site. To verify this observation, we generated PrP expression vectors coding for authentic or mutated murine PrPCs (i.e., codon 144 encoding tyrosine instead of tryptophan). After transfection into neuroblastoma cells, MAb L42 did not react with immunoblotted wild-type murine PrPC, whereas L42 epitope-tagged murine PrPC was strongly recognized. Immunoblot and fluorescence-activated cell sorting data revealed that tagged PrPC was correctly posttranslationally processed and translocated to the cell surface.  (+info)

Fatal familial insomnia: a new Austrian family. (4/2897)

We present clinical, pathological and molecular features of the first Austrian family with fatal familial insomnia. Detailed clinical data are available in five patients and autopsy in four patients. Age at onset of disease ranged between 20 and 60 years, and disease duration between 8 and 20 months. Severe loss of weight was an early symptom in all five patients. Four patients developed insomnia and/or autonomic dysfunction, and all five patients developed motor abnormalities. Analysis of the prion protein (PrP) gene revealed the codon 178 point mutation and methionine homozygosity at position 129. In all brains, neuropathology showed widespread cortical astrogliosis, widespread brainstem nuclei and tract degeneration, and olivary 'pseudohypertrophy' with vacuolated neurons, in addition to neuropathological features described previously, such as thalamic and olivary degeneration. Western blotting of one brain and immunocytochemistry in four brains revealed quantitative and regional dissociation between PrP(res)(the protease resistant form of PrP) deposition and histopathology. In the cerebellar cortex of one patient, PrP(res) deposits were prominent in the molecular layer and displayed a peculiar patchy and strip-like pattern with perpendicular orientation to the surface. In another patient, a single vacuolated neuron in the inferior olivary nuclei contained prominent intravacuolar granular PrP(res) deposits, resembling changes of brainstem neurons in bovine spongiform encephalopathy.  (+info)

Copper binding to the prion protein: structural implications of four identical cooperative binding sites. (5/2897)

Evidence is growing to support a functional role for the prion protein (PrP) in copper metabolism. Copper ions appear to bind to the protein in a highly conserved octapeptide repeat region (sequence PHGGGWGQ) near the N terminus. To delineate the site and mode of binding of Cu(II) to the PrP, the copper-binding properties of peptides of varying lengths corresponding to 2-, 3-, and 4-octarepeat sequences have been probed by using various spectroscopic techniques. A two-octarepeat peptide binds a single Cu(II) ion with Kd approximately 6 microM whereas a four-octarepeat peptide cooperatively binds four Cu(II) ions. Circular dichroism spectra indicate a distinctive structuring of the octarepeat region on Cu(II) binding. Visible absorption, visible circular dichroism, and electron spin resonance spectra suggest that the coordination sphere of the copper is identical for 2, 3, or 4 octarepeats, consisting of a square-planar geometry with three nitrogen ligands and one oxygen ligand. Consistent with the pH dependence of Cu(II) binding, proton NMR spectroscopy indicates that the histidine residues in each octarepeat are coordinated to the Cu(II) ion. Our working model for the structure of the complex shows the histidine residues in successive octarepeats bridged between two copper ions, with both the Nepsilon2 and Ndelta1 imidazole nitrogen of each histidine residue coordinated and the remaining coordination sites occupied by a backbone amide nitrogen and a water molecule. This arrangement accounts for the cooperative nature of complex formation and for the apparent evolutionary requirement for four octarepeats in the PrP.  (+info)

The yeast non-Mendelian factor [ETA+] is a variant of [PSI+], a prion-like form of release factor eRF3. (6/2897)

The yeast non-Mendelian factor [ETA+] is lethal in the presence of certain mutations in the SUP35 and SUP45 genes, which code for the translational release factors eRF3 and eRF1, respectively. One such mutation, sup35-2, is now shown to contain a UAG stop codon prior to the essential region of the gene. The non-Mendelian inheritance of [ETA+] is reminiscent of the yeast [PSI+] element, which is due to a self-propagating conformation of Sup35p. Here we show that [ETA+] and [PSI+] share many characteristics. Indeed, like [PSI+], the maintenance of [ETA+] requires the N-terminal region of Sup35p and depends on an appropriate level of the chaperone protein Hsp104. Moreover, [ETA+] can be induced de novo by excess Sup35p, and [ETA+] cells have a weak nonsense suppressor phenotype characteristic of weak [PSI+]. We conclude that [ETA+] is actually a weak, unstable variant of [PSI+]. We find that although some Sup35p aggregates in [ETA+] cells, more Sup35p remains soluble in [ETA+] cells than in isogenic strong [PSI+] cells. Our data suggest that the amount of soluble Sup35p determines the strength of translational nonsense suppression associated with different [PSI+] variants.  (+info)

Application of distance geometry to 3D visualization of sequence relationships. (7/2897)

SUMMARY: We describe the application of distance geometry methods to the three-dimensional visualization of sequence relationships, with examples for mumps virus SH gene cDNA and prion protein sequences. Sequence-sequence distance measures may be obtained from either a multiple sequence alignment or from sets of pairwise alignments. AVAILABILITY: C/Perl code and HTML/VRML files from http://www.nibsc.ac.uk/dg3dseq/  (+info)

Effectiveness of polyene antibiotics in treatment of transmissible spongiform encephalopathy in transgenic mice expressing Syrian hamster PrP only in neurons. (8/2897)

To date very few drugs have favorably influenced the course of transmissible spongiform encephalopathies. In previous studies, the polyene antibiotics amphotericin B (AmB) and MS-8209 prolonged the incubation time in Syrian hamsters of the 263K strain of scrapie, but AmB had no effect against other scrapie strains in Syrian hamsters. In the present experiments using transgenic mice expressing Syrian hamster PrP in neurons only, MS-8209 extended the life spans of animals infected with the 263K strain but not the DY strain. AmB was effective against both 263K and DY and prevented death in 18% of DY-infected animals. The AmB effect against strain 263K was more prominent in mice whose endogenous PrP gene had been inactivated by homologous recombination. It was unclear whether this difference was due to a change in the duration of the disease or to possible interactive effects between the mouse PrP gene and the drugs themselves. The effectiveness of treatment after intracerebral scrapie infection in transgenic mice expressing PrP only in neurons suggested that neurons are important sites of action for these drugs.  (+info)

A soluble, oligomeric beta-sheet-rich conformational variant of recombinant full-length prion protein, PrP beta, was generated that aggregates into amyloid fibrils, PrP betaf. These fibrils have physico-chemical and structural properties closely similar to those of pathogenic PrP Sc in scrapie-associated fibrils and prion rods, including a closely similar proteinase K digestion pattern and Congo red birefringence. The conformational transition from PrP C to PrP beta occurs at pH 5.0 in bicellar solutions containing equimolar mixtures of dihexanoyl-phosphocholine and dimyristoyl-phospholipids, and a small percentage of negatively charged dimyristoyl-phosphoserine. The same protocol was applicable to human, cow, elk, pig, dog and mouse PrP. Comparison of full-length hPrP 23-230 with the N-terminally truncated human PrP fragments hPrP 90-230, hPrP 96-230, hPrP 105-230 and hPrP 121-230 showed that the flexible peptide segment 105-120 must be present for the generation of PrP beta. Dimerization of ...
Prion protein (PrP) is a membrane glycosylphosphatidylinositol (GPI)-anchored glycoprotein that is encoded by the PRNP gene and is highly conserved among mammals. PrP contains an unstable region consisting of five octapeptide repeats; mutations in this region are associated with Creutzfeldt-Jakob disease (CJD), fatal familial insomnia, Gerstmann-Straussler disease, Huntington disease-like 1, and kuru (a type of transmissible spongiform encephalopathy, TSE). The function of PrP is not clear, although it is known to bind copper ions. PrP exists as a normal cellular isoform (PrPC) that can undergo refolding to a conformational isoform known as scrapie isoform (PrPSc). PrPSc forms compact aggregates that are highly resistant to proteolysis. The conversion of PrPC to PrPSc is postulated to be the mechanism involved in transmission of TSEs. PrP is also known as prion protein (p27-30); major prion protein, prion-related protein, CJD, GSS, ASCR, KURU, PRIP, PrPc, CD230, AltPrP, p27-30, PrP27-30, and ...
Prion protein (PrP) is a membrane glycosylphosphatidylinositol (GPI)-anchored glycoprotein that is encoded by the PRNP gene and is highly conserved among mammals. PrP contains an unstable region consisting of five octapeptide repeats; mutations in this region are associated with Creutzfeldt-Jakob disease (CJD), fatal familial insomnia, Gerstmann-Straussler disease, Huntington disease-like 1, and kuru (a type of transmissible spongiform encephalopathy, TSE). The function of PrP is not clear, although it is known to bind copper ions. PrP exists as a normal cellular isoform (PrPC) that can undergo refolding to a conformational isoform known as scrapie isoform (PrPSc). PrPSc forms compact aggregates that are highly resistant to proteolysis. The conversion of PrPC to PrPSc is postulated to be the mechanism involved in transmission of TSEs. PrP is also known as prion protein (p27-30); major prion protein, prion-related protein, CJD, GSS, ASCR, KURU, PRIP, PrPc, CD230, AltPrP, p27-30, PrP27-30, and ...
Prion rods, i.e. insoluble infectious aggregates of the N-terminally truncated form of the prion protein, PrP 27-30, and the corresponding recombinant protein, rPrP(90-231), were autoclaved in water, bovine lipid or lipid-water mixtures for 20 min at temperatures from 100 to 170 °C. A protocol was developed for the quantitative precipitation of small amounts of protein from large excesses of lipid. PrP remaining undegraded after autoclaving was quantified by Western blot and degradation factors were calculated. The Arrhenius plot of the rate of degradation vs temperature yielded linear relationships for prion rods in water or lipid-water as well as for rPrP(90-231) in lipid-water. The presence of lipids increased the heat stability of prion rods, especially at lower temperatures. Prion rods had a much higher thermal stability compared to rPrP. Autoclaving of prion rods in pure lipid gave different results - not simple degradation but bands indicative of covalently linked dimers, tetramers and higher
Prion diseases are fatal and incurable neurodegenerative diseases of humans and animals. Despite years of research, no therapeutic agents have been developed that can effectively manage or reverse disease progression. Recently it has been identified that recombinant prion proteins (rPrP) expressed in bacteria can act as inhibitors of prion replication within the in vitro prion replication system Protein Misfolding Cyclic Amplification (PMCA). Here, within PMCA reactions amplifying a range of ruminant prions including distinct Prnp genotypes/host species and distinct prion strains, recombinant ovine VRQ PrP displayed consistent inhibition of prion replication and produced IC50 values of 122 and 171 nM for ovine scrapie and bovine BSE replication, respectively. These findings illustrate the therapeutic potential of rPrPs with distinct TSE diseases.. ...
Define transmissible neurodegenerative disease. transmissible neurodegenerative disease synonyms, transmissible neurodegenerative disease pronunciation, transmissible neurodegenerative disease translation, English dictionary definition of transmissible neurodegenerative disease. n. 1. An abnormal condition of a part, organ, or system of an organism resulting from various causes, such as infection, inflammation, environmental...
Prion protein is the causative agent of the transmissible spongiform encephalopathies. According to the prion hypothesis, the infectious isoform of prion protein, termed PrPSc, replicates by interacting with cellular PrPC and mediating its conformational change into the disease-causing PrPSc (19). Compared with its well-defined pathological significance, the physiological function of PrPC remains unclear. PrPC is highly expressed not only by cells in the CNS but also by follicular DCs, mature myeloid cells, and activated T cells. This distribution suggests involvement of PrPC in immune surveillance (20).. Our present study defines a novel role for PrPC as an M-cell receptor for the uptake of pathogenic bacteria. PrPC on macrophages has been reported to recognize surface-exposed Hsp60 of B. abortus and to facilitate internalization of the bacteria (13); however, Fontes et al. (21) reported a contradictory result. Using Prnp−/− mice, they showed that B. suis infection is independent of PrPC ...
1. Vaccination-induced anti-prion protein antibodies are presently regarded as a promising approach toward treatment of prion diseases. Here, we investigated the ability of five peptides corresponding to three different regions of the bovine prion protein (PrP) to elicit antibodies interfering with PrP(Sc) propagation in prion-infected cells.2. Rabbits were immunized with free nonconjugated peptides. Obtained immune sera were tested in enzyme-linked immunosorbent assay (ELISA) and immunoblot for their binding to recombinant PrP and cell-derived pathogenic isoform (PrP(Sc)) and normal prion protein (PrP(c)), respectively. Sera positive in all tests were chosen for PrP(Sc) inhibition studies in cell culture.3. All peptides induced anti-peptide antibodies, most of them reacting with recombinant PrP. Moreover, addition of the serum specific to peptide 95-123 led to a transient reduction of PrP(Sc) levels in persistently prion-infected cells.4. Thus, anti-PrP antibodies interfering with PrP(Sc) ...
Background Imbalance of iron homeostasis has been reported in sporadic Creutzfeldt-Jakob-disease (sCJD) affected human and scrapie infected animal brains, but the contribution of this phenotype to disease associated neurotoxicity is unclear. Methodology/Principal Findings Using cell models of familial prion disorders, we demonstrate that exposure of cells expressing normal prion protein (PrPC) or mutant PrP forms to a source of redox-iron induces aggregation of PrPC and specific mutant PrP forms. Initially this response is cytoprotective, but becomes increasingly toxic with time due to accumulation of PrP-ferritin aggregates. Mutant PrP forms that do not aggregate are not cytoprotective, and cells show signs of acute toxicity. Intracellular PrP-ferritin aggregates induce the expression of LC3-II, indicating stimulation of autophagy in these cells. Similar observations are noted in sCJD and scrapie infected hamster brains, lending credence to these results. Furthermore, phagocytosis of PrP-ferritin
Prions are the enigmatic etiological agents of transmissible spongiform encephalopathies (TSEs), a class of fatal neurodegenerative diseases affecting humans and other mammals. The pathogenic prion protein is a misfolded form of the host-encoded prion protein and represents the predominant, if not sole, component of the infectious agent. Environmental routes of TSE transmission are implicated in epizootics of sheep scrapie and chronic wasting disease of deer, elk, and moose. Soil is the most plausible candidate for preserving prion infectivity in the environment. We have investigated prion attachment to and detachment from inorganic and organic soil particle surfaces and examined the effect of association with specific soil constituents on disease transmission. Interaction of prions with some phyllosilicate mineral surfaces is remarkably strong. Interestingly, rather than diminishing bioavailability, attachment to such particles enhances disease transmission. This finding suggests an explanation ...
Both prion protein and the structurally homologous protein doppel are associated with neurodegenerative disease by mechanisms which remain elusive. We have prepared murine doppel, and a mutant with one of the two disulphide bonds removed, in the expectation of increasing the similarity of doppel to prion protein in terms of conformation and stability. Unfolding studies of doppel and the mutant have been performed using far-UV CD over a range of solution conditions known to favour the α→β transformation of recombinant prion protein. Only partial unfolding of doppel or the mutant occurs at elevated temperature, but both exhibit full and reversible unfolding in chemical denaturation with urea. Doppel is significantly less stable than prion protein, and this stability is further reduced by removal of the disulphide bond between residues 95-148. Both doppel and the mutant are observed to unfold by a two-state mechanism, even under the mildly acidic conditions where prion protein forms an ...
Following intracerebral or peripheral inoculation of mice with scrapie prions, infectivity accumulates first in the spleen and only later in the brain. In the spleen of scrapie-infected mice, prions were found in association with T and B lymphocytes and to a somewhat lesser degree with the stroma, which contains the follicular dendritic cells (FDCs) but not with non-B, non-T cells; strikingly, no infectivity was found in lymphocytes from blood of the same mice. Transgenic PrP knockout mice expressing PrP restricted to either B or T lymphocytes show no prion replication in the lymphoreticular system. Therefore, splenic lymphocytes either acquire prions from another source or replicate them in dependency on other PrP-expressing cells. The essential role of FDCs in prion replication in spleen was shown by treating mice with soluble lymphotoxin-β receptor, which led to disappearance of mature FDCs from the spleen and concomitantly abolished splenic prion accumulation and retarded neuroinvasion ...
Conformational intermediates of the human prion protein huPrPC were characterized by a combination of hydrostatic pressure (up to 200 MPa) with two-dimensional NMR spectroscopy. All pressure effects showed to be reversible and there is virtually no difference in the overall pressure response between the folded core of the N-terminal truncated huPrPC(121-230) and the full-length huPrPC(23-230). The only significant differences in the pressure response of full-length and truncated PrP suggest that E168, H187, T192, E207, E211 and Y226 are involved in a transient interaction with the unfolded N-terminus. High-pressure NMR spectroscopy indicates that the folded core of the human prion protein occurs in two structural states N1and N2 in solution associated with rather small differences in free enthalpies (3.0 kJ/mol). At atmospheric pressure approximately 29% of the protein are already in the pressure favored conformation N2. There is a second process representing two possible folding intermediates ...
Single nucleotide polymorphisms (SNPs) and haplotype alleles within the prion gene (PRNP) coding sequence of domestic sheep (Ovis aries) are associated with genetic predisposition to scrapie, a transmissible spongiform encephalopathy disease of sheep. This report describes regions of linkage disequilibrium (LD) throughout the PRNP gene region in U.S. sheep and provides a genetic framework for identifying additional PRNP determinants associated with scrapie resistance. Four sequence tagged sites (i.e., STS or amplicons) totaling 3869 bp and spanning 20 kbp of genomic PRNP sequence were sequenced in a diverse panel of 90 sires representing ten popular U.S. breeds of sheep. Analysis of these sequences identified 36 previously unreported polymorphisms. In combination with two previously characterized STS, 62 polymorphisms were analyzed in a 20-kbp PRNP region in this panel of U.S. sheep. Two regions of strong LD and ten common haplotypes were identified. The haplotype encoding amino acid residues A, R, and
Conversion of prion protein (PrP) to an altered conformer, the scrapie PrP (PrPSc), is a critical step in the development of transmissible spongiform encephalopathies. Both Cu(II) and nucleic acid molecules have been implicated in this conversion. Full-length PrP can bind up to six copper ions; four Cu(II) binding sites are located in the octarepeat domain (residues 60-91), and His-96 and His-111 coordinate two additional copper ions. Experimental evidence shows that PrP binds different molecules, resulting in diverse cellular signaling events. However, there is little information about the interaction of macromolecular ligands with Cu(II)-bound PrP. Both RNA and DNA sequences can bind PrP, and this interaction results in reciprocal conformational changes. Here, we investigated the interaction of Cu(II) and nucleic acids with amyloidogenic non-octarepeat PrP peptide models (comprising human PrP residues 106-126 and hamster PrP residues 109-149) that retain His-111 as the copper-anchoring residue. The
Zanusso, G; Liu, D; Ferrari, S; Hegyi, I; Yin, X; Aguzzi, A; Hornemann, S; Liemann, S; Glockshuber, R; Manson, J C; Brown, P; Petersen, R B; Gambetti, P; Sy, M S (1998). Prion protein expression in different species: analysis with a panel of new mAbs. Proceedings of the National Academy of Sciences of the United States of America (PNAS), 95(15):8812-8816.. Raeber, A J; Race, R E; Brandner, S; Priola, S A; Sailer, A; Bessen, R A; Mucke, L; Manson, J C; Aguzzi, A; Oldstone, M B; Weissmann, C; Chesebro, B (1997). Astrocyte-specific expression of hamster prion protein (PrP) renders PrP knockout mice susceptible to hamster scrapie. EMBO Journal, 16(20):6057-6065.. ...
23284 Comment by Andrea LeBlanc: This interesting paper shows that quite a few of the disease-associated human prion mutations actually switch to the normal Doppel sequence. The doppel (i.e., doppelgaenger) gene is downstream of the PrP gene. Its protein resembles amino-terminally truncated PrP and interacts with PrP.) Doppel overexpression is neurotoxic. Therefore, the switch of PrP into a Doppel-like protein could indicate that Doppel and mutant PrP are neurotoxic through a similar mechanism. However, it remains to be seen if these mutant PrPs are neurotoxic or not.. Our work has focused on the function of normal prion protein in primary human neurons. I suspected a function for prion protein in cell death or cell survival because of some similarity between the BH2 domain of Bcl-2 proteins and the octapeptide repeat of prion protein. While we now know that PrP is not a member of the Bcl-2 family of proteins, it is, however, a strong neuroprotective agent against Bax-mediated cell death. We ...
Team:Valencia/head}} ,div id=HomeCenter> ,div id=Titulos> Regulating Mars temperature ,br> ,br> using a prion switch ,/div> ,br> ==Prions== In 1982 Stanley B. Prusiner created the term prion (or proteinacius infectious particle) to name the exclusively proteic infectious agent responsible of the transmissible spongiform encephalopathies (TSEs), a group of mammalian neurodegenerative disorders. According to the widely supported protein-only model, the prion mechanism of transmissibility arise from the ability of the prion form of the protein to promote the conformational change of the normal cellular form to the infectious prion forms (Prusiner, 1998). The infectious forms are mis-folded proteins that induce by polymerization the formation of an amyloid fold constituted by tightly packed beta sheets. These aggregates are insoluble fibrils that display resistance to proteolytic digestion and have affinity for aromatic dyes. ===Fungal prions=== In 1994 Reed Wickner proposed the prion nature ...
TY - JOUR. T1 - Structure-based view on [PSI+] prion properties. AU - Bondarev, S.A.. AU - Zhouravleva, G.A.. AU - Belousov, M.V.. AU - Kajava, A.V.. PY - 2015. Y1 - 2015. N2 - Yeast [PSI+] prion is one of the most suitable and well characterized system for the investigation of the prion phenomenon. However, until recently, the lack of data on the 3D arrangement of Sup35p prion fibrils hindered progress in this area. The recent arrival in this field of new experimental techniques led to the parallel and in-register superpleated β-structure as a consensus model for Sup35p fibrils. Here, we analyzed the effect of amino acid substitutions of the Sup35 protein through the prism of this structural model. Application of a newly developed computational approach, called ArchCandy, gives us a better understanding of the effect caused by mutations on the fibril forming potential of Sup35 protein. This bioinformatics tool can be used for the design of new mutations with desired modification of prion ...
Phenotypic heterogeneity of sCJD parallels that of animal prion diseases such as scrapie or transmissible mink encephalopathy. In these diseases, phenotypic variation has been related to both variation of the agent strain and host genetic factors-namely, thePRNP genotype.4 5 Prion strains are distinguishable by the neuropathology they produce, the regional pattern of intracerebral PrP-res accumulation, and, to some extent, by differing physicochemical properties of PrP-res, such as size and glycoform ratio of the protein.4-8 These signatures are reproducible and characteristic of a given strain when examined within syngenic hosts,4-8 but they may change after transmission to hosts with a different PRNPgenotype.5 9 Four distinct clinicopathological variants of sCJD have been recently identified in a series of 19 patients.2 The typical CJD phenotype (myoclonic variant) and the Heidenhain variant were linked to MM at codon 129 and to PrP-res type 1. The ataxic variant and the variant with kuru ...
In this study, we characterized the biochemical properties of a set of chimeric prion proteins wherein the ORD of Sup35p was replaced with that of PrP. The chimeric prion proteins were created by substituting the endogenous Sup35p ORD with the repeat domain of PrP containing five, eight, 11 and 14 oligopeptide repeats [40]. The repeat-expanded proteins show a remarkable set of properties that highlight their enhanced ability to aggregate and form amyloid fibers in vitro. These data agree with work done by others in which recombinant PrP (rPrP) with ORD expansions exhibit an enhanced ability to form amyloid fibers with increasing number of repeats [20, 46]. Our data also support previous work done with transgenic mice (Tg(PG14)) that express PrP harboring nine additional octapeptide repeats. These mice manifest a spontaneous form of prion disease [21]. Although the spontaneous form of the disease in the Tg(PG14) mice is not infectious, the protein aggregates and the animals display many of the ...
Prion protein 2 (dublet), also known as PRND, or Doppel protein, is a protein which in humans is encoded by the PRND gene. This gene is found on chromosome 20, approximately 20 kbp downstream of the gene encoding cellular prion protein, to which it is biochemically and structurally similar. The protein encoded by this gene is a membrane glycosylphosphatidylinositol-anchored glycoprotein that is found predominantly in testis. Mutations in this gene may lead to neurological disorders. GRCh38: Ensembl release 89: ENSG00000171864 - Ensembl, May 2017 GRCm38: Ensembl release 89: ENSMUSG00000098754 - Ensembl, May 2017 Human PubMed Reference:. Mouse PubMed Reference:. Entrez Gene: PRND prion protein 2 (dublet). Moore RC, Lee IY, Silverman GL, et al. (1999). Ataxia in prion protein (PrP)-deficient mice is associated with upregulation of the novel PrP-like protein doppel. J. Mol. Biol. 292 (4): 797-817. doi:10.1006/jmbi.1999.3108. PMID 10525406. Weissmann C, Aguzzi A (1999). Perspectives: ...
The role of carcinine in signaling at the Drosophila photoreceptor synapse. Gavin BA, Arruda SE, Dolph PJ. PLoS Genet. 2007 Dec;3(12):e206. PMID: 18069895 [PubMed - indexed for MEDLINE]. Accelerated accumulation of misfolded prion protein and spongiform degeneration in a Drosophila model of Gerstmann-Sträussler-Scheinker syndrome. Gavin BA, Dolph MJ, Deleault NR, Geoghegan JC, Khurana V, Feany MB, Dolph PJ, Supattapone S. J Neurosci. 2006 Nov 29;26(48):12408-14. PMID: 17135402 [PubMed - indexed for MEDLINE]. An essential role for endocytosis of rhodopsin through interaction of visual arrestin with the AP-2 adaptor. Orem NR, Xia L, Dolph PJ. J Cell Sci. 2006 Aug 1;119(Pt 15):3141-8. Epub 2006 Jul 11. PMID: 16835270 [PubMed - indexed for MEDLINE]. Molecular cloning of the pawn locus from Drosophila melanogaster. Arruda SE, Dolph PJ. Gene. 2003 May 22;310:169-73. PMID: 12801644 [PubMed - indexed for MEDLINE]. Post-transcriptional suppression of pathogenic prion protein expression in Drosophila ...
Egg candling gadget made by the BE department. An egg candling gadget is used to identify infertile eggs and monitor the development of embryos. Chicken embryos were used for tick research in the yolk sac method ...
The NMR structures of the recombinant human prion protein, hPrP(23-230), and two C-terminal fragments, hPrP(90-230) and hPrP(121-230), include a globular domain extending from residues 125-228, for which a detailed structure was obtained, and an N-terminal flexibly disordered tail. The globular domain contains three alpha-helices comprising the residues 144-154, 173-194, and 200-228 and a short anti-parallel beta-sheet comprising the residues 128-131 and 161-164. Within the globular domain, three polypeptide segments show increased structural disorder: i.e., a loop of residues 167-171, the residues 187-194 at the end of helix 2, and the residues 219-228 in the C-terminal part of helix 3. The local conformational state of the polypeptide segments 187-193 in helix 2 and 219-226 in helix 3 is measurably influenced by the length of the N-terminal tail, with the helical states being most highly populated in hPrP(23-230). When compared with the previously reported structures of the murine and Syrian ...
In the central nervous system, cellular prion proteins are found in astrocytes and neurons. There has been evidence showing that they prolong the survival9 as well as affect the differentiation of these structures. Scientists have found that cellular prions interact with NCAM, neuronal cell adhesion molecules, in astrocytes and this causes neurogenesis. Another role that the cellular prions might be involved in is the differentiation process of neurons. Scientists have found that when the ligand, STI1 (secreted from astrocytes) binds a receptor on the cellular prion glycoprotein membrane, the neurons differentiate. There were much lower levels of neurogenesis in neuron-astrocyte co-cultures, when they did not express the Prnp gene. Furthermore, they suggested that the interaction between cellular prion proteins and STI1 may play a role in protecting against apoptosis, as they have seen in neurons located in the hippocampus and the retina8 . It is likely that there are other molecular factors in ...
Cellular prion protein (PrpC) is a glycoprotein usually associated with membranes via its glycosylphosphatidylinositol (GPI) anchor. The trans-conformational form of this protein (PrpSC) is the suggested agent responsible for transmissible neurodegenerative spongiform encephalopathies. This protein has been shown on sperm and in the reproductive fluids of males. Antibodies directed against the C-terminal sequence near the GPI-anchor site, an N-terminal sequence, and against the whole protein showed that the Prp isoforms were compartmentalized within the reproductive tract of the ram. Immunoblotting with the three antibodies showed that the complete protein and both N- and C-terminally truncated and glycosylated isoforms are present within cauda epididymal fluid and seminal plasma. Moreover, we demonstrate that in these fluids, the PrpC isoforms are both in a soluble state as well as associated with small membranous vesicles (epididymosomes). We also report that only one major glycosylated 25 kDa ...
Cellular prion protein, a membrane protein, is expressed in all mammals. Prion protein is also found in human blood as an anchorless protein, and this protein form is one of the many potential sources of misfolded prion protein replication during transmission. Many studies have suggested that β-amyloid1-42 oligomer causes neurotoxicity associated with Alzheimers disease, which is mediated by the prion protein that acts as a receptor and regulates the hippocampal potentiation. The prevention of the binding of these proteins has been proposed as a possible preventative treatment for Alzheimers disease; therefore, a greater understanding of the binding hot-spots between the two molecules is necessary. In this study, the epitope mapping immunoassay was employed to characterize binding epitopes within the prion protein and complementary epitopes in β-amyloid. Residues 23-39 and 93-119 in the prion protein were involved in binding to β-amyloid1-40 and 1-42, and monomers of this protein interacted ...
1B10: Solution structure of a 142-residue recombinant prion protein corresponding to the infectious fragment of the scrapie isoform.
Elastic and Plastic Strain Properties of Sand. This paper describes the results of tests using conventional triaxial apparatus with loading and unloading, on samples of medium sand with two different unit weights. The method is used to study the elastic and plastic volumetric and axial strains under the conditions of hydrostatic and deviator stress. It is shown that under hydrostatic compression, the elastic volumetric strain of medium sand is always greater than its plastic volumetric strain. The ratio of elastic volumetric strain to plastic volumetric strain may decrease as the hydrostatic pressure increases. Other conclusions are also described.
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Protein-only (prion) epigenetic elements confer unique phenotypes by adopting alternate conformations that specify new traits. Given the conformational flexibility of prion proteins, protein-only inheritance requires efficient self-replication of the underlying conformation. To explore the cellular …
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Huntingtons and Parkinsons diseases are neurodegenerative disorders associated with unusual protein interactions. Although the origin and evolution of these diseases are completely different, characteristic deposits of protein aggregates (huntingti
Activation of phospholipase A2 (PLA2) and the subsequent metabolism of arachidonic acid (AA) to prostaglandins have been shown to play an important role in neuronal death in neurodegenerative disease. Here we report the effects of the prion peptide fragment HuPrP106-126 on the PLA2 cascade in primary cortical neurons and translocation of cPLA2 to neurites. Exposure of primary cortical neurons to HuPrP106-126 increased the levels of phosphorylated cPLA2 and caused phosphorylated cPLA2 to relocate from the cell body to the cellular neurite in a PrP-dependent manner, a previously unreported observation. HuPrP106-126 also induced significant AA release, an indicator of cPLA2 activation; this preceded synapse damage and subsequent cellular death. The novel translocation of p-cPLA2 postulated the potential for exposure to HuPrP106-126 to result in a re-arrangement of the cellular cytoskeleton. However p-cPLA2 did not colocalise significantly with F-actin, intermediate filaments, or microtubule-associated
A proposal by Dr. Harlan Caldwell at the Rocky Mountain Laboratories (RML) involving the deliberate transfer of a tetracycline resistance trait to non-ocular strains of Chlamydia trachomatis has been submitted to the NIH Office of Biotechnology Activities (OBA). The introduction of tetracycline...
Here, we report the development and further characterisation of a novel PrP-specific monoclonal antibody: 2A11. By Western blot analysis, 2A11 reacts with PrPC from a variety of species including cow, sheep, pig, hamster, rabbit, cat, dog, deer and mouse but fails to react with human, chicken and turtle PrP. Reactivity to PrPC in Western blot was found to be dependent on the redox state of the protein since binding of mAb 2A11 to its epitope was more effective in reducing conditions. 2A11 binding site was mapped within a region comprised by residues 171-179 (six octarepeats bovine PrP notation; 163-171 for the ovine PrP notation). Interestingly, in immunohistochemistry (IHC) analysis, immunoreactivity was greatly enhanced after proteinase K (PK) sample treatment, while little or no reaction was observed in non-PK-treated BSE samples and samples from healthy animals. Quantitative differences in reactivity to BSE prions after PK treatment were also observed, to a lesser extent, by Western blot ...
Inserting genes from psychrophilic, or cold-loving, bacteria, into bacterial pathogens could prove a cool new way for developing vaccines, according to microbiologist Francis Nano at the University of Victoria, British Columbia, Canada, and his collaborators there and at the Rocky Mountain Laboratories in Hamilton, Mont. Under control of genes from psychrophiles, the pathogens grow only at relatively low temperatures but not at 37°C. Thus, the modified bacteria
As a member of the wwPDB, the RCSB PDB curates and annotates PDB data according to agreed upon standards. The RCSB PDB also provides a variety of tools and resources. Users can perform simple and advanced searches based on annotations relating to sequence, structure and function. These molecules are visualized, downloaded, and analyzed by users who range from students to specialized scientists.
While prions can be thought of like a disease, that is not a good description. Prions are just misfolded proteins, that can make similar proteins misfold as well.. To understand what this means, proteins can be compared to hundreds of springs attached together in a large blanket of springs. Some of the springs are extension springs, and some are contraction springs. To execute its function, a protein will fold up this blanket of springs into a ball.. And it will fold up exactly the same way every time.. But a prion is a mistake in the folding up process. If it folds up incorrectly, the protein does not work. And to make matters worse, it can tell other proteins of its type to fold up incorrectly as well.. Importantly, priors happen constantly in our bodies, and just as constantly, they are destroyed by our bodies. But infectious prions are not *recognized* as prions by our bodies, so they are not destroyed, and can try to tell all the other proteins like them to misfold as well. And once you ...
Fingerprint Dive into the research topics of A dominant-negative mutant inhibits multiple prion variants through a common mechanism. Together they form a unique fingerprint. ...
The properties of this strain that contribute to its usefulness as a cloning strain are described below. The genotypes underlying these properties appear in parentheses.
The properties of this strain that contribute to its usefulness as a cloning strain are described below. The genotypes underlying these properties appear in parentheses.
WEDNESDAY, MAY 17, 2017 CWD, TSE, PRION, Cattle, Pigs, Sheep, and Humans aka Mad Cow Disease http://chronic-wasting-disease.blogspot.com/2017/05/cwd-tse-prion-cattle-pigs-sheep-and.html kind regards, terry
The demonstration of prion secretion in sheep in a variety of matrices including milk (Maddison et al. (2009) J. Virol. 83:8293-8296), saliva (Maddison et al. (2010) J. Inf. Dis. 201:1672-1676.) and faeces (Terry et al. (2011) Vet. Res. 42:65). Excretion/secretion occurs through long asymptomatic periods of disease development and from sheep with a range of PRNP genotypes, including those with limited lymphoreticular involvement in prion replication (Gough et al. (2011) J. Virol. 86:566-571 ...
Mechanism of PrP-mediated myopathy. Accumulation of an N-terminal truncated PrP C1 fragment in muscle activates p53 resulting in the induction of p53-regulated
Abskharon, R. N. N., G. Giachin, A. Wohlkonig, S. H. Soror, E. Pardon, G. Legname, and J. Steyaert, Probing the N-terminal β-sheet conversion in the crystal structure of the human prion protein bound to a nanobody., J Am Chem Soc, vol. 136, issue 3, pp. 937-44, 2014 Jan 22. ...
For example, people use terms like ввdirectionality,вв ввblobbiness,вв ввrandomness,вв and so on. System suitability в resolution minimum of 5.
View Prnp/Prnp Tg(Prnp*D177N*M128V)A21Rchi/Tg(Prnp*D177N*M128V)A21Rchi involves: 129S7/SvEvBrd * C57BL/6 * CBA: phenotypes, images, diseases, and references.
In a new study NYU School of Medicine researchers report that they have found several chemical compounds, including an antidepressant, that have powerful effects against brain-destroying prion infections in mice, opening ...
Prions[edit]. For more details on this topic, see Fungal prions.. Prions are infectious forms of proteins. In general, proteins ... PSI+ and URE3, discovered in yeast in 1965 and 1971, are the two best studied of this type of prion.[76][77] Prions can have a ... Fungal prions are considered by some to be epigenetic because the infectious phenotype caused by the prion can be inherited ... Prions can be viewed as epigenetic agents capable of inducing a phenotypic change without modification of the genome.[110] ...
Prions are so named because they appear to contain only protein. No evidence of nucleic acid has been found in any prion ... Once it was discovered that prions were the real cause of TSEs and that prions contained no nucleic acid, the term virions was ... However, some general characteristics of prion diseases are listed below. Prions: cause diseases that are confined to the CNS ... However, TSEs are more correctly classified as prion diseases. Prions are misfolded proteins that are "infectious" because they ...
The often fatal prion diseases is among the most significant. A prion (PrP) is a transmembrane cellular protein found widely in ... There are more than twenty mutations of the prion protein gene (PRNP) that are known to be associated with or that are directly ... Ziegler, J; Sticht, H; Marx, UC; Müller, W; Rösch, P; Schwarzinger, S (2003). "CD and NMR studies of prion protein (PrP) helix1 ... Brusiner, Stanley (1998). "Prions". Proc Natl Acad Sci USA. National Academy of Sciences. 95 (23): 13363-83. Bibcode:1998PNAS ...
According to the prion paradigm, certain proteins misfold into shapes that are rich in beta-sheet secondary structure. In this ... Prusiner SB (1998). "Prions". Proceedings of the National Academy of Sciences USA. 95 (23): 13363-13383. Bibcode:1998PNAS... ... Walker LC; Jucker M (2015). "Neurodegenerative diseases: Expanding the prion concept". Annual Review of Neuroscience. 38: 87- ... have likened this process to the formation and spread of prions in diseases known as spongiform encephalopathies or prion ...
ANSWER: prions. 2011 Collegiate Novice. Bonuses usually have multiple parts that are related by some common thread and may or ...
"Prion. p. 160.. *^ Stefano Infessura, Diario della città di Roma (1303-1494), Ist. St. italiano, Tip. Forzani, Roma 1890, pp. ... Sex Lives of the Popes, Nigel Cawthorne, Prion, London, 1996.. *Popes and Anti-Popes, John Wilcock, Xlibris Corporation, 2005.[ ...
prion: main component of prion diseases and transmissible spongiform encephalopathies.. Intracellular mechanisms[edit]. Protein ... Hooper NM (April 2005). "Roles of proteolysis and lipid rafts in the processing of the amyloid precursor protein and prion ...
PrionsEdit. Main article: Prion. Prions are misfolded proteins that can transfer their misfolded state to other normally folded ... PrionEdit. Despite many attempts, to date no therapy has been shown to halt the progression of prion diseases.[28] ... "The prion diseases" Stanley B. Prusiner, Scientific American *^ Viral Special Pathogens Branch , [26] Moved , CDC Archived May ... It is estimated that in rural settings, 90% or more of livestock deaths can be attributed to pathogens.[23][24] The prion ...
PrionsEdit. Further information: Fungal prions. Prions are infectious forms of proteins. In general, proteins fold into ... PSI+ and URE3, discovered in yeast in 1965 and 1971, are the two best studied of this type of prion.[74][75] Prions can have a ... Fungal prions are considered by some to be epigenetic because the infectious phenotype caused by the prion can be inherited ... Prions can be viewed as epigenetic agents capable of inducing a phenotypic change without modification of the genome.[110] ...
Cohen, F. E.; Pan, K. M.; Huang, Z.; Baldwin, M.; Fletterick, R. J.; Prusiner, S. B. (1994-04-22). "Structural clues to prion ... Spongiform encephalopathies Prion Disease (Kuru, CJD, GSS, BSE) Alzheimer's disease Sickle cell anemia Parkinsons Huntington's ... Weissmann, C.; Enari, M.; Klöhn, P‐C.; Rossi, D.; Flechsig, E. (2002-12-01). "Transmission of Prions". The Journal of ... Multiple models illustrating this recruitment function exist, including the PrP protein in prion disease. The PrP protein is ...
Prion mutationsEdit. Prions are proteins and do not contain genetic material. However, prion replication has been shown to be ... "Lifeless' prion proteins are 'capable of evolution'". Health. BBC News Online. London. 1 January 2010. Archived from the ... The human gene PRNP codes for the major prion protein, PrP, and is subject to mutations that can give rise to disease-causing ...
Fungal prions are considered by some to be epigenetic because the infectious phenotype caused by the prion can be inherited ... PSI+ and URE3, discovered in yeast in 1965 and 1971, are the two best studied of this type of prion. Prions can have a ... The yeast prion PSI is generated by a conformational change of a translation termination factor, which is then inherited by ... Prions can be viewed as epigenetic agents capable of inducing a phenotypic change without modification of the genome. Direct ...
Foster PR (October 2000). "Prions and blood products". Annals of Medicine. 32 (7): 501-13. doi:10.3109/07853890009002026. PMID ...
How the prions that cause CWD spread is unknown, but recent research indicates that prions can be excreted by deer and elk, and ... Researchers in July 2019 stated that "with all the research on the malignity of prions, and the permanence of prions in the ... when the prions were mixed with clay. This was important because the prions had already been shown by 2006 to bind with sandy ... while the longevity of CWD prion is unknown, the scrapie prion has been measured to endure for 16 years. The PrPCWD protein is ...
Ornithologist Brian Bell found that prions were confined to cliff faces at Crozier Point in 1962 and noted "any bird landing ... "Cat among the prions". Forest & Bird. 373: 24-25. Harper, Grant (2010). "Diet of feral cats on Subantarctic Auckland Island". ... the Ranui Station cats were recorded to kill 60 Antarctic prions over three months in 1942. ...
Prion; 2004), Diamonds to Dust: The Life and Death of Jayne Mansfield (Frank Ferruccio; Outskirts Press; 2007, and Did Success ...
Prion protein is detectable in lymphoid and appendix tissue up to two years before the onset of neurological symptoms in vCJD. ... As of 2018, evidence suggests that while there may be prions in the blood of individuals with vCJD, this is not the case in ... No history of CJD in a first degree relative or prion protein gene mutation in the person. vCJD is a separate condition from ... A 2012 study by the Health Protection Agency showed that around 1 in 2,000 people in the UK shows signs of abnormal prion ...
ISBN 978-1-4116-1432-1. Bergan, Ronald; Fuller, Graham; Malcolm, David (1994). Academy Award Winners (illustrated ed.). Prion. ...
PRION. Botham, Noel. Valentino: The First Superstar. Metro Books, 2002. ISBN 1-84358-013-6. p. 325. Dos Passos, John. U.S.A. ...
Prion. ISBN 978-1-85375-815-7. Edwards, Kasey (2011). OMG! That's Not My Child... He's sharing. Prion. ISBN 978-1-85375-814-0. ... both published by Prion Books, an imprint of Carlton Publishing Group. The books spoof the picture book series 'That's Not My ...
"Prion". Online Etymology Dictionary. Harper, Douglas. "Formica". Online Etymology Dictionary. Archibald, S.B.; Cover, S. P.; ...
It is a prion disease of the brain. It is usually caused by a mutation to the gene encoding protein PrPC. It has two forms: ... Other prion diseases are similar to FFI and could be related, but are missing the D178N gene mutation. As of 2016, 24 cases of ... Similar to other prion diseases, the diagnosis can only be confirmed by a brain autopsy at post-mortem. Fatal insomnia has no ... The Prion Alliance was established by husband and wife duo Eric Minikel and Sonia Vallabh after Vallabh's mother was diagnosed ...
Prion. p. 114. ISBN 1-85375-376-9. Badsey, Stephen (2014). The German Corpse Factory: a study in First World War Propaganda. ...
Sehnal F, Sutherland T (2008). "Silks produced by insect labial glands". Prion. 2 (4): 145-53. doi:10.4161/pri.2.4.7489. PMC ...
Zou WQ, Gambetti P (April 2005). "From microbes to prions the final proof of the prion hypothesis". Cell. 121 (2): 155-7. doi: ... Prusiner, SB (2004). Prion Biology and Diseases (2 ed.). Cold Spring Harbor, NY: Cold Spring Harbor Laboratory Press. ISBN 0- ... The best known form of such inducible proteopathy is prion disease, which can be transmitted by exposure of a host organism to ... Grad LI, Fernando SM, Cashman NR (May 2015). "From molecule to molecule and cell to cell: prion-like mechanisms in amyotrophic ...
Nussbaum JM, Seward ME, Bloom GS (Jan-Feb 2013). "Alzheimer disease: a tale of two prions". Prion. 7 (1): 14-9. doi:10.4161/pri ... Sanghera N, Swann MJ, Ronan G, Pinheiro TJ (October 2009). "Insight into early events in the aggregation of the prion protein ... The other protein implicated in Alzheimer's disease, tau protein, also forms such prion-like misfolded oligomers, and there is ... a protein fold shared by other peptides such as the prions associated with protein misfolding diseases. Research suggests that ...
Prion. 105 Marlin, Randal (2002). Propaganda and the Ethics of Persuasion. Broadview. pp. 73-4. "No. 32162". The London Gazette ...
Prion. pp. 105-106. ISBN 1-85375-376-9. Ponsonby, Arthur (1928). Falsehood in Wartime. New York: Dutton. pp. 102, 111-112. ...
Prion. p. 165. Crick (1982), p. 504 Jack Denny in Stephen Wadhams Remembering Orwell, Penguin Books 1984 Bob Edwards in Audrey ...
Rodriguez, Cynthia M; Bennet, James P; Johnson, Cristopher J (1 January 2012). "Lichens: Unexpected anti-prion agents?". Prion ... Bennet, James P; Rodriuguez, Cynthia M; Johnson, Cristopher (July 2012). "Prion protein degradation by lichens of the genus ... "Degradation of the Disease-Associated Prion Protein by a Serine Protease from Lichens". PLOS ONE. 6 (5): e19836. Bibcode: ... many in the Cladonia genus have been shown to produce serine proteases capable of the degradation of pathogenic forms of prion ...
Prion diseases are usually rapidly progressive and always fatal.. Identified Prion Diseases. Listed below are the prion ... The National Prion Disease Pathology Surveillance Centerexternal icon. *National Institutes of Health: Detecting Human Prion ... The causative agents of TSEs are believed to be prions. The term "prions" refers to abnormal, pathogenic agents that are ... The functions of these normal prion proteins are still not completely understood. The abnormal folding of the prion proteins ...
... is a prion disease that was first described in 1996 in the United Kingdom. ... Variant Creutzfeldt-Jakob disease (vCJD) is a prion disease that was first described in 1996 in the United Kingdom. There is ... Each disease also has a particular genetic profile of the prion protein gene. Both disorders are invariably fatal brain ... and are caused by an unconventional transmissible agent called a prion. ...
Prions, the pathogens that cause scrapie in sheep, can survive in the ground for several years, as researchers have discovered ... Are the prions transmitted not only by direct contact, but also by the environment - perhaps by the pastures? How long do ... Prions, the pathogens that cause scrapie in sheep, can survive in the ground for several years, as researchers have discovered ... How long do BSE and CWD prions survive in the ground? "To find this out, we urgently need to carry out further tests. The ...
A prion is an infectious agent consisting of a protein that is mis-folded. It can cause several central nervous system diseases ... A prion can rearrange the structure of a normal protein, causing it to become a prion as well (which is why it is an infectious ... Prions. A prion is an infectious agent consisting of a protein that is mis-folded. It can cause several central nervous system ... In fact, prions arent even alive. They are merely an infectious protein, like a virus or a viroid. A commonly known prion is ...
... prion (fr); Prion (jv); Prioni (hr); prion (nn); Prion (id); Priyon (ht); Viroid và Prion (vi); پری اون (pnb); Prion (ro); ... Prion (sh); прион (sr-ec); Prion (oc); прионы (ru); prion (cs); prion (en); بريون (ar); Prion (br); prion (sv) psialoproteína ... prion (es); 朊毒體 (yue); Prion (hu); Prion (nl); Prioi (eu); プリオン (ja); Prión (ast); Prion (ms); پریون (fa); Prion (de); Prión ( ... Prion, Prionid (et); Priões, Príons, Prions, Prião, Prion (pt); Прион (sr); 프라이온 (ko); Prion xəstəlikləri (az); Prion (hr); ...
The demonstration of prion secretion in sheep in a variety of matrices including milk (Maddison et al. (2009) J. Virol. 83:8293 ... Prions Research Group. The University of Nottingham. School of Veterinary Medicine and Science. Sutton Bonington Campus, ... In addition we have shown that prions are found in a wide range of farm locations including metal, wood, concrete and plastic ... Prion diseases or transmissible spongiform encephalopathies (TSEs) are fatal neurological disorders with long incubation ...
What is a prion you ask? Prions are almost as mysterious to the scientists that research them as… ... Fish drowning in stupid: Now with added prions!. Anne Hart is still on her anti-frankenfishscapade. Actually, this latest ... Clue for Possible Treatment of Prion Diseases. While looking for information for my last post, I encountered another ... tags: Bovine spongiform encephalopathy, BSE, mad cow disease, Creutzfeldt-Jakob Disease, CJD, pathogenic mutation, prion ...
When prion proteins go askew they are the primary agent of fatal brain diseases such as mad cow disease and vCJD. New research ... Prions Prevent Alzheimers. By Rick Nauert PhD. ~ 2 min read When prion proteins go askew they are the primary agent of fatal ... However, theres still a lot of work to be done in looking at levels of prions in the human system and how these may alter as ... Using cells grown in the lab, the team looked at the effect of high and low levels of normal prion protein on the successful ...
Prion Infectivity Pinpointed. A small section of protein turns out to be responsible for the infectious properties of prions. ...
To distinguish this pathogen from viruses and viroids, the term "prion" was introduced to emphasize its proteinaceous and ... The book reviews advances in studies of prions, which - as considereable evidence indicates - are novel pathogens composed only ... The Folding Intermediate Concept of Prion Protein Formation and Conformational Links to Infectivity ... was awarded the 1997 Nobel Prize in Physiology and Medicine for his pioneering discovery of prions. ...
Amyloid, Prions, and Other Protein Aggregates. Volume 309, Part 1 of Amyloid, Prions, and Other Protein Aggregates: Part [A]-C ...
prions* (rhyming with aeons) is an acronym for proteinaceous infectious particles. The term was coined in 1982 by Stanley B. ... Prion Biology COPYRIGHT 2002 The Gale Group Inc.. Prion. Unlike all other infectious agents, prions contain no deoxyribonucleic ... Prions Encyclopedia of Public Health COPYRIGHT 2002 The Gale Group Inc.. PRIONS. Prions are infectious proteinaceous particles ... Prions. Resources. Prions are proteins that are infectious. Indeed, the name prion is derived from "proteinaceous infectious ...
A crucial step in the transmission of these diseases is the formation of protease-resistant forms of the prion protein (PrP), ... No effective treatment currently exists for these diseases, which are caused by misfolded prion proteins that wreak havoc in ... Previous research had shown that tetracycline drugs alter the properties and neurotoxicity of prion proteins in vitro. Fabrizio ... Because the drug seems to weaken the prions protective armor, the authors conclude that "tetracyclines are immediate ...
Prions readily bind to steel wires, which can thus be used to detect the presence of prions, as well as to infect brains in ... Prions are believed to be a polymer of misfolded proteins. Collinge says that nascent seeds of prions might be forming and ... the new prions caused disease with different characteristics from that produced by the scrapie prions normally used in the ... If pre-existing prions are being concentrated on the steel wires, the rate at which this happens should be directly ...
Biological Function for Prions?. December 30, 2003 1:40 PM Subscribe. Remember Prions? Sure, but Do They Remember (for) You? ... Also, Prion Diseases, MerckManual, a general laypersons overview. It has been known for some time that prions play a large ... More info on prions and BSE here.. Its a self-link (I work for them), but salient.. posted by rocketman at 5:03 PM on December ... Prions are about the coolest, and scariest, thing going.. posted by five fresh fish at 5:45 PM on December 30, 2003 ...
Abnormal prions might not be the infectious agents that cause BSE after all, prompting fears that UK testing might be missing ... Abnormal prion proteins assumed to be the infectious agents that cause mad cow disease and variant Creutzfeldt-Jakob disease ... Normally when animals die of a BSE-like disease, their brains are full of holes and clogged up with abnormal prion proteins - ...
Prion disease represents a group of conditions that affect the nervous system in humans and animals. Explore symptoms, ... The other 85 to 90 percent of cases of prion disease are classified as either sporadic or acquired. People with sporadic prion ... Because they can run in families, these forms of prion disease are classified as familial. Familial prion diseases, which have ... is a type of acquired prion disease in humans that results from eating beef products containing PrPSc from cattle with prion ...
... prion: …the four species is the fairy prion (P. turtur), about 20 cm (8 inches) long; the largest is the broad-billed prion (P ... Most of the prions breed in burrows on Antarctic and sub-Antarctic islands. The broad-billed prion is more northerly in ... In prion. …the four species is the fairy prion (P. turtur), about 20 cm (8 inches) long; the largest is the broad-billed prion ... Most of the prions breed in burrows on Antarctic and sub-Antarctic islands. The broad-billed prion is more northerly in ...
Prion is short for "proteinaceous infectious particle." Dr. Stanley B. Prusiner gave the name "prion" to the substance he and ... Then why didnt all mammals have prion-related diseases? The prion protein could exist in one of two different forms. "In ... Feline spongiform encephalopathy: Infection with prion-contaminated MBM found in cats. Examples of human prion diseases include ... "Prions exist normally as innocuous cellular proteins, however, prions possess an innate capacity to convert their structures ...
Working with Team Prion · Getting started as a team mentor for FIRST Robotics ... In the fall of 2009, I asked around about opportunities to work with FIRST teams and Team Prion was getting started in the ...
... and they could not properly say that the wife had a normal prion sequence nor a normally functioning prion protein. The codon ... This suggests that prion infection could be supported by these cells, as expression of PrPC is essential for prion agent ... with severe gliosis and punctate prion imunoreactivity. Genetically, the husbands prion gene was normal: no changes and ... The moufflon prion gene has not been sequenced. No pathology was seen in wild moufflon on Cyprus. In my opinion, this is an ...
Surveillance of prion diseases in humans. In: Baker H, Ridley RM, editors. Methods in molecular medicine: prion diseases. ... Neuropathological diagnosis of human prion disease. In: Baker H, Ridley RM, editors. Methods in molecular medicine: prion ... Molecular analysis of prion strain variation and the aetiology of new variant CJD. Nature 1996;383:685-90. * Zerr I, Bodemer ... Limited proteolysis of PrPCJD by Western blot analysis shows four patterns of protease-resistant prion protein (12,13). No ...
Prion research, the next frontiers. Nature 1 Nov 1997. The article in last weeks Nature, "Prion research, the next frontiers ... DNA/protein sequence actually used to make bovine prion. Who/what is Prionics AG?. Quick commentary on new anti-prion antibody ... Imagery of possible rogue prion dimer. Accuracy of Figure 3b, 3c questioned. Aguzzi/Weissmann on prion research frontiers. ... Conformational intermediates of purified human prion. Brain receptor role links Alzheimers and smoking. Prion-specific epitope ...
Pachyptila turtur, fairy prion breeds on subtropical and subantarctic islands Pachyptila belcheri, slender-billed prion breeds ... broad-billed prion breeds on islands off of New Zealand and Tristan da Cunha group Pachyptila desolata, Antarctic prion breeds ... This is a list of the genera, species, and subspecies belonging to the prions, which belong to the Procellariiformes. ... Salvins prion breeds on Prince Edward Islands, Crozet Island, Amsterdam Island, and St. Paul Island Pachyptila salvini salvini ...
... uptake and transport infectious prions, according to researchers at The University of Texas Health Science Center at Houston ( ... Prions have a long incubation period." Sotos team analyzed the retention of infectious prion protein and infectivity in wheat ... The team also learned that infectious prion proteins could be detected in plants exposed to urine and feces from prion-infected ... Prions are the protein-based infectious agents responsible for a group of diseases called transmissible spongiform ...
Using transgenic mice expressing human prion protein as a model of cross-species prion transmission, the authors show that ... the zoonotic potential of scrapie prions remains unknown. Mice genetically engineered to overexpress the human prion protein ( ... Here we show that a panel of sheep scrapie prions transmit to several tgHu mice models with an efficiency comparable to that of ... These models can propagate human prions without any apparent transmission barrier and have been used used to confirm the ...
The curative properties of stem cells may rely on prions, a new study suggests, the type of protein made infamous by mad cow ... Prions are a special class of protein that can change the shape and function of other proteins around them. While these are ... The curative properties of stem cells may rely on prions, a new study suggests, the type of protein made infamous by mad cow ... The question of how prions sustain stem cell activity remains unanswered, but the finding is a first step to understanding the ...
Stanley Prusiner introduced the term prion- (proteinaceous infectious particle) and proposed that the infectious agent in prion ... Prion diseases typically have long incubation periods and are rapidly progressive once clinical symptoms begin. They are ... Etiopathology and Genetics (Table 1) Prion protein (PrPc) is a normal protein coded for by a gene- the human PRNP gene (PRNP) ... Prion diseases are unique in that they can be inherited, can occur sporadically, or be infectious. ...
Among the myriad of things that can afflict us, prions remain one of the creepiest pathogens out there. A new report by the ... Prion Disease Can Lurk In Your Brain For 30 Years Before Quickly Killing You. ... A Lab Accident Likely Led to a Womans Death From Brain-Destroying Prions 9 Years Later. ... One Study Finds Zombie Deer Prion Disease May Not Infect Humans, But Risk Remains. ...
Fungal prions have helped to suggest mechanisms of conversion that may apply to all prions, though fungal prions appear ... Similarly, removing the prion domain from a fungal prion protein inhibits prionogenesis. This modular view of prion behaviour ... For their mechanistic similarity to mammalian prions, they were termed yeast prions. Subsequent to this, a prion has also been ... Atkinson CJ, Zhang K, Munn AL, Wiegmans A, Wei MQ (2016). "Prion protein scrapie and the normal cellular prion protein". Prion ...
  • Prion diseases or transmissible spongiform encephalopathies (TSEs) are a family of rare progressive neurodegenerative disorders that affect both humans and animals. (cdc.gov)
  • Prion diseases are usually rapidly progressive and always fatal. (cdc.gov)
  • Listed below are the prion diseases identified to date. (cdc.gov)
  • Both disorders are invariably fatal brain diseases with unusually long incubation periods measured in years, and are caused by an unconventional transmissible agent called a prion. (cdc.gov)
  • Prion diseases or transmissible spongiform encephalopathies (TSEs) are fatal neurological disorders with long incubation periods (3-6 years in cattle, 15-50 years in humans). (nottingham.ac.uk)
  • Together, our data reveal the transmission routes of scrapie prions in a natural host and emphasise the significant challenges in controlling the spread of such diseases. (nottingham.ac.uk)
  • When prion proteins go askew they are the primary agent of fatal brain diseases such as mad cow disease and vCJD. (psychcentral.com)
  • Alzheimer's and diseases like variant Creutzfeldt-Jakob Disease follow similar patterns of disease progression and in some forms of prion disease share genetic features. (psychcentral.com)
  • No effective treatment currently exists for these diseases, which are caused by misfolded prion proteins that wreak havoc in the brain and lead to neurodegeneration. (scientificamerican.com)
  • A crucial step in the transmission of these diseases is the formation of protease-resistant forms of the prion protein (PrP), which cannot be broken down by the body and subsequently accumulate in the brain. (scientificamerican.com)
  • Here's a great article based on a speech about BSE and prion diseases by Edward Scolnick, President of Merck Research. (metafilter.com)
  • Familial prion diseases, which have overlapping signs and symptoms, include familial Creutzfeldt-Jakob disease (CJD), Gerstmann-Sträussler-Scheinker syndrome (GSS), and fatal familial insomnia (FFI). (medlineplus.gov)
  • Aguzzi A, Heikenwalder M. Pathogenesis of prion diseases: current status and future outlook. (medlineplus.gov)
  • Then why didn't all mammals have prion-related diseases? (sourcewatch.org)
  • Since the switch from normal to infectious protein form is belived to cause prion-related neurological wasting diseases in several different species, prions have "been defined as 'small proteinaceous infectious particles which resist inactivation by procedures that modify nucleic acids. (sourcewatch.org)
  • Prion diseases are often called spongiform encephalopathies because of the post mortem appearance of the brain with large vacuoles in the cortex and cerebellum. (sourcewatch.org)
  • As the Nobel Assembly explained: "Prions exist normally as innocuous cellular proteins, however, prions possess an innate capacity to convert their structures into highly stabile conformations that ultimately result in the formation of harmful particles, the causative agents of several deadly brain diseases of the dementia type in humans and animals. (sourcewatch.org)
  • Prion diseases may be inherited, laterally transmitted, or occur spontaneously. (sourcewatch.org)
  • Prion Diseases , BBC/UK , 1999. (sourcewatch.org)
  • Stanley B. Prusiner, " Prion Diseases and the BSE Crisis ," Science magazine, 2003. (sourcewatch.org)
  • Polymorphisms at codon 129 have been correlated with genetic susceptibility to human prion diseases ( 19 ). (mad-cow.org)
  • Prions are the protein-based infectious agents responsible for a group of diseases called transmissible spongiform encephalopathy, which includes bovine spongiform encephalopathy (mad cow disease) in cattle, scrapie in sheep, variant Creutzfeldt-Jakob disease in humans and chronic wasting disease (CWD) in deer, elk and moose. (medicalnewstoday.com)
  • Transmissible spongiform encephalopathies (TSE), or prion diseases, are fatal neurodegenerative disorders that affect a large spectrum of mammalian species. (nature.com)
  • Prion diseases, or transmissible spongiform encephalopathies (TSE), are a group of neurodegenerative disorders affecting both humans and animals. (psu.edu)
  • Prion diseases are unique in that they can be inherited, can occur sporadically, or be infectious. (psu.edu)
  • Stanley Prusiner introduced the term prion- (proteinaceous infectious particle) and proposed that the infectious agent in prion diseases is composed mainly or entirely of an abnormal conformation of an otherwise normal host-encoded glycoprotein called the prion protein (PrP)1. (psu.edu)
  • Prion diseases typically have long incubation periods and are rapidly progressive once clinical symptoms begin. (psu.edu)
  • Protein aggregation and amyloid formation are central pathologic events in a wide range of neurodegenerative illnesses, including Alzheimer's, Parkinson's, and prion diseases ( 1 ). (pnas.org)
  • Perhaps the best understood of these disorders are the prion diseases, in which the host-encoded, cellular prion protein (PrP C ) undergoes structural isomerization to an infectious form, termed PrP Sc ( 2 ). (pnas.org)
  • Prion diseases are a rare group of fatal neurodegenerative disorders of humans and animals that manifest primarily as progressive dementia and ataxia. (nature.com)
  • Unique to these diseases is the prion, a misfolded isoform of the prion protein that can transmit disease from cell to cell or host to host by associating with, and transforming, normal prion protein into the misfolded isoform (the pathogenic scrapie-inducing form). (nature.com)
  • This review will focus on the clinical and histopathologic features of the genetic prion diseases. (nature.com)
  • Genetic prion diseases constitute a continuum of clinical and pathologic manifestations broadly segregated into three principal phenotypes designated as familial Creutzfeldt-Jakob disease (fCJD), Gerstmann-Sträussler-Scheinker (GSS) syndrome, and familial fatal insomnia (FFI). (nature.com)
  • There are infectious diseases which are not caused by either bacteria or viruses, but by a newly discovered type of infective agent called a prion . (creation.com)
  • Understanding the role polyanions play in infectious prion formation may bring scientists one step closer to being able to prevent or treat prion diseases. (nih.gov)
  • Page 210 - 'Concern about prions has arisen with the advent of prion animal diseases such as bovine spongiform encephalopathy (BSE) in the United Kingdom and other parts of Europe. (rense.com)
  • There is a tremendous amount that is unknown about prion diseases -- both human and animal. (rense.com)
  • The brain damage that characterizes Alzheimer's disease may originate in a form similar to that of infectious prion diseases such as bovine spongiform encephalopathy (mad cow) and Creutzfeldt-Jakob, according to newly published research by The University of Texas Health Science Center at Houston. (news-medical.net)
  • In a new study NYU School of Medicine researchers report that they have found several chemical compounds, including an antidepressant, that have powerful effects against brain-destroying prion infections in mice, opening the door to potential treatments for human prion diseases. (news-medical.net)
  • The Pan-Provincial Vaccine Enterprise Inc. (PREVENT), a national Centre of Excellence for Commercialization and Research (CECR), has signed an exclusive license with Amorfix Life Sciences Ltd. of Missisauga, Ontario for the use of their proprietary ProMIS technology in developing vaccines (active immunotherapy) for the treatment of diseases caused by the formation of misfolded prion. (news-medical.net)
  • The University of Western Ontario is one of nine universities which will share 2.9 million dollars in research grants announced by PrioNet Canada to study Prion diseases and neurodegenerative disorders including Alzheimer's. (news-medical.net)
  • Prion diseases such as Creutzfeldt-Jakob disease in humans and bovine spongiform encephalopathy (BSE) in cattle are transmissible neurodegenerative diseases linked to the aggregation of the prion protein in the central nervous system. (news-medical.net)
  • Unlocking the mechanisms that cause neurodegenerative prion diseases may require a genetic key, suggest new findings reported by University of Illinois at Chicago distinguished professor of biological sciences Susan Liebman. (news-medical.net)
  • Researchers from the Centers for Disease Control and Prevention have examined the potential for human exposure to prion diseases, looking at hunting, venison consumption, and travel to areas in which prion diseases have been reported in animals. (news-medical.net)
  • Prion diseases are a group of progressive and fatal neurodegenerative disorders characterized by deposition of scrapie prion protein (PrPSc) in the CNS. (jci.org)
  • The most recent advances in understanding neuronal death in prion diseases are presented. (springer.com)
  • Prion diseases serve as an experimental model for all neurodegenerative conditions. (springer.com)
  • What are prion diseases? (hopkinsmedicine.org)
  • Prion diseases comprise several conditions. (hopkinsmedicine.org)
  • Prion diseases can affect both humans and animals and are sometimes spread to humans by infected meat products. (hopkinsmedicine.org)
  • Prion diseases occur when normal prion protein, found on the surface of many cells, becomes abnormal and clump in the brain, causing brain damage. (hopkinsmedicine.org)
  • Experts still don't know a lot about prion diseases, but unfortunately, these disorders are generally fatal. (hopkinsmedicine.org)
  • Who is at risk for prion diseases? (hopkinsmedicine.org)
  • What are the symptoms of prion diseases? (hopkinsmedicine.org)
  • How are prion diseases diagnosed? (hopkinsmedicine.org)
  • Prion diseases are confirmed by taking a sample of brain tissue during a biopsy or after death. (hopkinsmedicine.org)
  • Healthcare providers, however, can do a number of tests before to help diagnose prion diseases such as CJD, or to rule out other diseases with similar symptoms. (hopkinsmedicine.org)
  • Prion diseases should be considered in all people with rapidly progressive dementia. (hopkinsmedicine.org)
  • How are prion diseases treated? (hopkinsmedicine.org)
  • Prion diseases can't be cured, but certain medicines may help slow their progress. (hopkinsmedicine.org)
  • Can prion diseases be prevented? (hopkinsmedicine.org)
  • Newer regulations that govern the handling and feeding of cows may help prevent the spread of prion diseases. (hopkinsmedicine.org)
  • As prion diseases progress, people with these diseases generally need help taking care of themselves. (hopkinsmedicine.org)
  • The discovery, which opens up new directions for researchers studying the currently untreatable prion diseases in humans and animals, is reported in this week s Nature by Salk Institute scientist Roland Riek and colleagues, along with collaborators in France and Switzerland. (innovations-report.com)
  • This research opens up new directions for researchers studying prion diseases in humans and other animals, since targeting the beta-sheet shape might turn out to be a strategy for controlling the feared and untreatable brain-wasting prion diseases such as bovine spongiform encephalopathy. (innovations-report.com)
  • The study also may help to improve our understanding of such neurodegenerative diseases as Alzheimer s, in which brain cells gradually "silt up" with structures similar to the prion beta-sheet that are connected to brain cell death. (innovations-report.com)
  • Prions, those self-replicating proteins that are responsible for scrapie, mad cow disease, and human neurologic diseases such as Creutzfeldt-Jakob and Kuru, have been notoriously difficult to pin down in the cell. (alzforum.org)
  • Elucidating the nature of prion toxicity may, therefore, shed some light on other neurodegenerative diseases. (alzforum.org)
  • This paper underscores the importance of immuno-EM in determining the subcellular localization of disease-linked peptides, and provides further parallels between prion diseases and AD, two neurodegenerative diseases associated with dementia, neuronal loss, and cerebral plaques. (alzforum.org)
  • Prion diseases are transmissible neurodegenerative disorders that include scrapie in sheep, bovine spongiform encephalopathy (BSE) in cattle and Creutzfeldt-Jakob disease (CJD) in humans. (nih.gov)
  • The principal component of the infectious agent responsible for these diseases appears to be an abnormal isoform of the host-encoded prion protein (PrP), designated PrP(Sc). (nih.gov)
  • Prion diseases are transmissible to the same or different mammalian species by inoculation with, or dietary exposure to, infected tissues. (nih.gov)
  • The occurrence of variant CJD in humans and the experimental confirmation that it is caused by the same prion strain as BSE has highlighted the need for intensive study into the pathogenesis of these diseases and new diagnostic and therapeutic approaches. (nih.gov)
  • these have been termed prion-like diseases. (wikipedia.org)
  • Lastly, it centers on the structure and biology of prions, as well as the diseases these pathogens cause. (elsevier.com)
  • The questions are meant to tease out possible exposure to bovine spongiform encephalopathy or vCJD, but the incubation period for human prion diseases such as vCJD may be longer than 60 years, according to researchers who studied the closely related disease kuru in former cannibals in New Guinea. (organicconsumers.org)
  • The research, based on studies of prion infectivity in yeast, solves one of the great puzzles about prions: If they are infectious proteins with no genetic material of their own and no ability to mutate genetically, how can a single prion exist in different strains that can cause different diseases? (eurekalert.org)
  • It shows that shape change accounts for strain differences, and it lays the groundwork for research to determine the physical differences that allow a prion to change shape and cause different diseases. (eurekalert.org)
  • The prion diseases are a large group of related neurodegenerative conditions, which affect both animals and humans. (medscape.com)
  • The misfolded form of cellular prion protein (PrPC) is the main component of the infectious agent of transmissible spongiform encephalopathies and the validated biomarker for these diseases. (psu.edu)
  • Prion diseases, also known as transmissible spongiform encephalopathies, are invariably fatal neurodegenerative diseases for which there are no efficacious treatments. (ingentaconnect.com)
  • The problem with the prion diseases is that, because there is so much unknown, and because there are so many different disciplines involved, even within biology, there really isn't enough collaboration. (rense.com)
  • If validated in larger studies, the method could be used to diagnose prion diseases and prevent disease transmission through blood transfusions. (nih.gov)
  • Prion diseases are a group of rare, fatal brain diseases that affect animals and humans. (nih.gov)
  • According to Dr. Christina J. Sigurdson, professor of pathology at UC San Diego and Davis, who was on the team, 6 "Our findings have implications for both estimating the risk of sCJD transmission and for development of diagnostic tests for prion diseases before symptoms become apparent. (organicconsumers.org)
  • Rabbits are immune to prion diseases. (technologyreview.com)
  • Prions cause a number of fatal diseases such as mad cow disease in cattle, scrapie in sheep and kuru and Creutzfeldt-Jakob disease (CJD) in humans. (technologyreview.com)
  • In recent years, however, biologists have discovered several animals that are immune to prion diseases. (technologyreview.com)
  • This salt bridge might be a potential drug target for prion diseases," says Zhang. (technologyreview.com)
  • Researchers at Berkeley Lab's Molecular Foundry have developed an effective way of testing for prion diseases, a group of fatal neurodegenerative illnesses caused by abnormally folded copies of naturally occurring proteins. (news-medical.net)
  • Our peptoid beads have the ability to detect the misfolded proteins that act as infectious agents, so it could have a significant impact in the realm of prion diseases, but we have also shown that it can seek out the large aggregated proteins that are the disease agents in Alzheimer's and Parkinson's diseases, among others. (news-medical.net)
  • He continued, 'Prion diseases are rare, but there are many misfolded protein-based diseases, which affect millions of people, that are also very poorly understood. (news-medical.net)
  • And like prion diseases, we need a way to diagnose these slow-onset conditions in the years before symptoms arise. (news-medical.net)
  • Prion diseases, which occur in many species of mammals, start to develop when prion proteins begin folding in an abnormal manner and then induce other normal copies of the protein to also adopt the misfolded shape. (news-medical.net)
  • People think prion diseases are a different group because they are rare and because they are infectious and Alzheimer's is not," he said. (alzforum.org)
  • The most dramatic (and unnerving) of the protein aggregation diseases are those caused by prions , which are proteins that can catalyze infectious misfolding. (sciencemag.org)
  • A number of aminothiazole compounds have shown efficacy in animal models of prion diseases, though, but (just to make things trickier) drug-resistant prions have been shown to develop under these conditions as well. (sciencemag.org)
  • The role of the pathological form of the prion protein in diseases such as scrapie is now well established, but the function of the normal prion protein in healthy individuals is still unclear. (sciencemag.org)
  • The normal function of prion protein (PrP) is usually disregarded at the expense of the more fascinating role of PrP in transmissible prion diseases. (nih.gov)
  • Prions are the causative agent in fatal neurological diseases affecting humans and animals. (sciencemag.org)
  • The disease is variant Creutzfeld-Jacob disease (vCJD), one of a group of diseases known as transmissible spongiform encephalopathies (TSEs), which are caused and transmitted by abnormal forms of prion proteins. (scienceinschool.org)
  • These diseases create large fluid-filled holes in the brain tissue because the accumulation of aberrant prions causes the neurons (nerve cells) to die. (scienceinschool.org)
  • Nevertheless, there are still those who believe that prion diseases are actually caused by unconventional viruses and that prion proteins are just part of this mysterious virus. (scienceinschool.org)
  • Special attention is paid to prion proteins from mammalian species, which are prone to amyloid-like prion diseases due to a unique aggregation pathway. (biomedsearch.com)
  • Prion diseases such as sporadic Creutzfeldt-Jakob disease in humans or atypical bovine spongiform encephalopathy, a form of mad cow disease, occur rarely and at random. (thaindian.com)
  • The findings raise the remote possibility that prion diseases may be transmitted through surgical procedures involving the skin. (eurekalert.org)
  • The authors emphasize that prion diseases cannot be spread through casual contact, and call for further studies to uncover how the misfolded proteins come to reside in the skin. (eurekalert.org)
  • Our findings have implications for both estimating the risk of sCJD transmission and for development of diagnostic tests for prion diseases before symptoms become apparent. (genengnews.com)
  • Prion diseases occur when misshapen prion proteins accumulate in the brain and cause lesions that can lead to progressive neurodegeneration. (genengnews.com)
  • This molecular region shows high species variability and has been implicated in specific interactions with a so far not further characterized "protein X," and it is related to the species barrier for transmission of prion diseases. (rcsb.org)
  • All TSEs result in the gradual and irreversible degeneration of the brain and are fatal Basics Proteins Prion Diseases Mabbott et al. (prezi.com)
  • Pathogenesis of prion diseases: current status andfuture outlook. (prezi.com)
  • Diagnosing prion diseases: needs, challenges, and hopes. (prezi.com)
  • 1999. Investigation of variant Creutzfeldt-Jakob disease and other human prion diseases with tonsil biopsy samples. (prezi.com)
  • Scientists investigating how prion diseases destroy the brain have observed a new form of the disease in mice that doesn't cause the sponge-like brain deterioration typically seen in these disorders. (preventdisease.com)
  • Prion diseases (also known as transmissible spongiform encephalopathies) are rare, fatal conditions that cause the brain to develop lesions so that it looks like a sponge. (preventdisease.com)
  • Scientists at NIH's National Institute of Allergy and Infectious Diseases (NIAID), along with collaborators at the Veterinary Laboratories Agency in Scotland, genetically removed the GPI anchor from study mice, preventing the prion protein from fastening to cells and thereby allowing it to diffuse freely in the fluid outside the cells. (preventdisease.com)
  • Our study indicates that 2 types of brain damage occur in prion diseases: abnormal prion protein plaques that destroy brain blood vessels and displace brain tissue, and abnormal prion protein without plaques that leads to the sponge-like damage to nerve cells," says lead author Dr. Bruce Chesebro, chief of the Laboratory of Persistent Viral Diseases at NIAID's Rocky Mountain Laboratories. (preventdisease.com)
  • The findings demonstrate that prions, an unusual class of infectious proteins, can make copies of themselves without the presence of viral DNA or RNA, damage brain tissue, and cause neurological diseases. (scienceblog.com)
  • We hope that our findings lead to a blood-based diagnostic test which can identify prion diseases such as CJD, in their early stages," says Professor Hill, "to enable interventional therapies which could slow or halt disease progression. (edu.au)
  • Researchers at NYU School of Medicine have found that immunization prolongs the incubation period for prion diseases such as Creutzfeldt-Jakob disease and may have therapeutic value for other neurodegenerative illness such as Alzheimer's disease. (scienceblog.com)
  • The capabilities of viruses, viroids and prions and the diseases they cause. (brightkite.com)
  • Prions are best known as the infectious proteins causing mad cow and related diseases, and a growing number of proteins with similar properties are implicated in disorders such as Alzheimer s and Parkinson s. (cshlpress.com)
  • This will ensure that general readers can navigate the various topics covered in this book and fully appreciate the impact prion research will continue to have on our understanding of major diseases and human and fungal biology. (cshlpress.com)
  • Diseases such as Creutzfeldt-Jakob disease and kuru develop when PrP proteins form prions by misfolding, clumping together, and spreading from cell to cell. (cshlpress.com)
  • some of these prion diseases include such devastating illnesses as Alzheimer's and Parkinson's and possibly type 2 diabetes. (cshlpress.com)
  • Written and edited by experts in the field, this collection from Cold Spring Harbor Perspectives in Medicine covers the progress that has recently been made in our understanding of the pathophysiology of prion diseases, as well as ongoing efforts to develop effective therapeutics. (cshlpress.com)
  • Therapies for human and animal diseases caused by prions are also covered. (cshlpress.com)
  • Can prion diseases be treated? (bigthink.com)
  • Key to the sensor concept is that prion diseases are a process of conformational change responding to a driving force, the binding of the abnormal conformer to the normal protein and that propagation of conformational change is directly correlated with "infectivity. (sbir.gov)
  • Prions , which are mutated or improperly folded proteins, were only recently discovered in 1982, and researchers were surprised to learn that these agents were infectious, like viruses, and capable of causing fatal brain diseases. (sixwise.com)
  • Prions cause a variety of fatal brain diseases in both animals and humans. (sixwise.com)
  • Diseases caused by prions are known as transmissible spongiform encephalopathies (TSEs), and they include disorders that affect both humans and animals. (sixwise.com)
  • Prion diseases can also occur sporadically and may be inherited. (sixwise.com)
  • Prion diseases are invariably lethal neurodegenerative diseases, associated with the structural conversion of the cellular isoform of the prion protein to its pathological, disease-associated isoform. (intechopen.com)
  • This chapter deals with these fascinating and sometimes contrasting aspects of prion biology, with an emphasis on the immunization protocols developed for prophylaxis and treatment of prion diseases. (intechopen.com)
  • Transmissible spongiform encephalopathies (TSEs) or prion diseases are invariably lethal neurodegenerative diseases afflicting a wide variety of species, including humans [ 1 ]. (intechopen.com)
  • Misfolded proteins are a factor in a number of diseases, including prion diseases, Alzheimer's, and Parkinson's. (microbes.info)
  • The main etiology of the prion diseases is related to conformational changes in the PrPc molecule, which occur after its internalization (Prusiner, 1998). (usp.br)
  • Infectious prions (short for proteinaceous infectious particles ) are associated with some 20 different diseases in humans and animals, including mad cow disease and a rare human form, Creutzfeldt-Jakob disease. (scripps.edu)
  • The fatal diseases, Kuru disease and Creutzfeld-Jakob disease (CJD), which are akin to mad cow disease, are caused by mysterious transmissible proteins known as prions . (icr.org)
  • The term "prions" refers to abnormal, pathogenic agents that are transmissible and are able to induce abnormal folding of specific normal cellular proteins called prion proteins that are found most abundantly in the brain. (cdc.gov)
  • The functions of these normal prion proteins are still not completely understood. (cdc.gov)
  • The abnormal folding of the prion proteins leads to brain damage and the characteristic signs and symptoms of the disease. (cdc.gov)
  • Prions are 'rogue' proteins, versions of naturally occurring proteins with a different 3D structure. (answers.com)
  • A prion is a misfolded protein that fosters misfolding in other normal proteins, thereby resulting in disease. (answers.com)
  • Prions are mis-folded proteins, so they would be classified as none of the above. (answers.com)
  • Prions are infectious proteins and they cause a structural change to other proteins that they interact with and that is how they cause damage. (answers.com)
  • Probably the most famous prion disease is Bovine Spongiform Encephalitis (mad cow) where the structural change that the prion causes to the proteins in the brain causes holes to appear in the tissue, making it look like a sponge. (answers.com)
  • They found an apparent role for normal prion proteins in preventing Alzheimer's disease. (psychcentral.com)
  • Our experiments have shown that the normal prion proteins found in brain cells reduce the formation of beta-amyloid, a protein that binds with others to build plaques in the brain that are found in Alzheimer's disease,'' explains Professor Hooper. (psychcentral.com)
  • Further evidence for the protective role of normal prion proteins is provided by mutated versions that are linked to genetic forms of prion disease because beta-amyloid fragments are able to form when the normal prion protein is corrupted by genetic mutation. (psychcentral.com)
  • Until now, the normal function of prion proteins has remained unclear, but our findings clearly identify a role for normal prion proteins in regulating the production of beta-amyloid and in doing so preventing formation of Alzheimer's plaques.Whether this function is lost as a result of the normal ageing process, or if some people are more susceptible to it than others we don't know yet. (psychcentral.com)
  • Previous research had shown that tetracycline drugs alter the properties and neurotoxicity of prion proteins in vitro. (scientificamerican.com)
  • After an epic series of experiments, a group of researchers has observed and reproduced what could be the spontaneous generation of prions--rogue misfolded proteins that have been implicated in the destruction of the central nervous system. (scientificamerican.com)
  • Human samples have traditionally proved less amenable to PMCA, and the misfolding of prion proteins is believed to occur at a much lower rate in humans than in mice. (scientificamerican.com)
  • Prions are believed to be a polymer of misfolded proteins. (scientificamerican.com)
  • Abnormal prion proteins assumed to be the infectious agents that cause mad cow disease and variant Creutzfeldt-Jakob disease might not be to blame after all. (newscientist.com)
  • Normally when animals die of a BSE-like disease, their brains are full of holes and clogged up with abnormal prion proteins - mis-folded versions of normal brain-cell proteins. (newscientist.com)
  • The team also learned that infectious prion proteins could be detected in plants exposed to urine and feces from prion-infected hamsters and deer. (medicalnewstoday.com)
  • Prions are a special class of protein that can change the shape and function of other proteins around them. (newscientist.com)
  • Andrew Steele, Cheng Cheng Zhang and colleagues used radiation to deplete the bone marrow of mice genetically engineered to not produce the prion proteins. (newscientist.com)
  • The question of how prions sustain stem cell activity remains unanswered, but the finding is a first step to understanding the destructive streak of misshapen prion proteins, Steele says. (newscientist.com)
  • Prions are infectious proteins that cause illness when they fold abnormally in the brain. (kingcounty.gov)
  • Instead, they affect the brain structure by acting as a template, inducing proteins with normal folding to convert to the abnormal prion form. (news-medical.net)
  • These newly formed mis-folded proteins, in turn, act as further templates for the conversion of more normal proteins, leading to an exponential accumulation of prions in the tissue of the central nervous system. (news-medical.net)
  • Cellular enzymes referred to as proteases can break down the normal protein, but prion proteins are resistant to this and subsequently accumulate in the brain tissue as they replicate. (news-medical.net)
  • Now, infectious prions have successfully been created in the laboratory for the first time, providing insight into how these deadly proteins form. (nih.gov)
  • Scientists have long thought that the brain damage is caused by abnormal prion proteins that clump together and accumulate in brain tissue. (nih.gov)
  • A person's ability to battle viruses at the cellular level remarkably resembles the way deadly infectious agents called prions misfold and cluster native proteins to cause disease, UT Southwestern Medical Center researchers report. (news-medical.net)
  • Essentially clumps of misfolded proteins, prions cause neurodegenerative disorders, such as mad cow/Creutzfeld-Jakob disease, in humans and animals. (news-medical.net)
  • A prion is a type of protein that can trigger normal proteins in the brain to fold abnormally. (hopkinsmedicine.org)
  • So tiny that they cannot been visualized even with the most powerful microscopes, prion proteins exist in two forms in nature: a normal (non-infectious) shape and the abnormal structure that occurs in mad cow disease, scrapie, kuru and several other brain infections. (innovations-report.com)
  • Prions are misfolded proteins with the ability to transmit their misfolded shape onto normal variants of the same protein. (wikipedia.org)
  • Prions form abnormal aggregates of proteins called amyloids, which accumulate in infected tissue and are associated with tissue damage and cell death. (wikipedia.org)
  • A prion disease is a type of proteopathy, or disease of structurally abnormal proteins. (wikipedia.org)
  • The word prion, coined in 1982 by Stanley B. Prusiner, is derived from protein and infection, hence prion, and is short for "proteinaceous infectious particle", in reference to its ability to self-propagate and transmit its conformation to other proteins. (wikipedia.org)
  • The blood treatment method involves removing white cells from the blood through leukoreduction, and then removing prions from the red-cell concentrate using a technique commonly employed for purifying proteins for drug research. (organicconsumers.org)
  • The technique involves the use of a specific ligand, selected from among millions of possible candidates, that has high binding affinity with both normal and abnormally folded proteins -- in this case, the prion that causes scrapie. (organicconsumers.org)
  • A prion is thought to cause disease by inducing other proteins to adopt its contorted shape and form sheets called amyloids. (eurekalert.org)
  • The UCSF study applies the versatile organism to studies of proteins and prion infectivity. (eurekalert.org)
  • To explore the link between prion strains and the conformation of the misfolded proteins in the amyloid sheets, the researchers first generated amyloids at different temperatures. (eurekalert.org)
  • These amyloid plaques are immunoreactive with antibodies to the prion protein and do not immunoreact with antibodies to other amyloidogenic proteins, such as the amyloid-beta (which is deposited in Alzheimer disease). (medscape.com)
  • Worse, prion proteins are tough. (halfbakery.com)
  • The weakness of prions is that they ARE proteins, and all proteins are assembled by various biological processes. (halfbakery.com)
  • I submit that we need to direct our research at enzymes suited to breaking down prion proteins. (halfbakery.com)
  • UnaBubba, yes, but this is exacly why I'm discussing enzymes and not some other means of breaking down prion proteins. (halfbakery.com)
  • PMCA relies on the characteristic nature of prions to cause certain healthy proteins to clump abnormally and convert into prions. (nih.gov)
  • Soto's group first combined healthy proteins with known concentrations of infectious vCJD prions. (nih.gov)
  • This increased the number of prions that could then convert healthy proteins into prions. (nih.gov)
  • Prions are abnormal and infectious forms of proteins that collect in brain tissue, causing cells to die. (organicconsumers.org)
  • In the last couple of years, molecular biologists have identified the structure of the proteins in these immune species that in other animals cause prion disease. (technologyreview.com)
  • The idea is that it might be possible to stabilise prion proteins in cattle, sheep and humans using an artificial salt bridge, similar to the one in dogs, horses and rabbits. (technologyreview.com)
  • As recently reported in the journal PLOS ONE , the team has developed a unique test that can isolate prion proteins in body fluids taken from animals. (news-medical.net)
  • Once the beads are added to a body fluid sample, they attach to prion protein aggregates, but not normal proteins. (news-medical.net)
  • The abnormal prion proteins then aggregate to form clumps, which are deposited throughout the nervous system where they induce cell death and cause the brain to have a sponge-like appearance. (news-medical.net)
  • I remember reading that there was no danger of taking up prions from plants, with claims that plants couldn't take up something as large as proteins. (virology.ws)
  • The proteins in question are the β amyloid of Alzheimer disease (AD) and the prion protein that causes transmissible spongiform encephalopathy, the only protein misfolding disease known to be contagious in people. (alzforum.org)
  • When they looked at protein aggregation in vitro, seeding Aβ preparations with prions produced an acceleration of aggregation, and amyloid fibrils accelerated the appearance of misfolded prion proteins. (alzforum.org)
  • It is not shown whether the fibril-induced prions are infectious, but the results suggest that the two proteins have the potential to mutually accelerate each other's misfolding and aggregation. (alzforum.org)
  • One reason for that is that Alzheimer's researchers have not really looked at prion proteins, Soto told ARF. (alzforum.org)
  • Prion proteins, worryingly, are known to adhere to metal surfaces and to be resistant to many standard methods of cleaning and sterilization. (sciencemag.org)
  • Prions are specific proteins found mainly in the nervous system, where - in their normal forms - they may have important functions. (scienceinschool.org)
  • Infectious prions are abnormal (aberrant) forms of prion proteins that replicate inside the host by forcing normal proteins of the same type to adopt the aberrant structure. (scienceinschool.org)
  • Prions are the only known case of self-propagating pathogenic (disease-causing) proteins, and they are able to cause severe illness even though they seem to be just protein molecules: unlike bacteria, viruses or other known pathogens, they have no information encoded in nucleic acids (DNA or RNA) about how to invade and replicate within the host. (scienceinschool.org)
  • Despite being a significantly popular current subject of investigations, the etiology, structure, and function of both normal and anomalous prion proteins still hold many mysteries. (biomedsearch.com)
  • In the case of prion proteins the following question is of the most importance - can chaperones influence different stages of the formation of pathological aggregates (these vary from intermediate oligomers to mature amyloid-like fibrils) and the whole transition from native prion protein to its amyloid-like fibril-enriched form? (biomedsearch.com)
  • Infectious prion proteins - the causative agents of the fatal neurodegenerative disorder Creutzfeldt-Jakob disease - can be detected in the skin of afflicted individuals, researchers now report. (eurekalert.org)
  • The discovery could lead to the development early diagnostic tests for the disease-which is caused by abnormal forms of normally harmless prion proteins-but also suggests that the disease might be transmitted through procedures such as corneal grafts. (genengnews.com)
  • Prion proteins expressed in E. coli bacteria. (genengnews.com)
  • As expected, the three variant hPrP(121-230) structures have the same global architecture as the previously determined wild-type bovine, human, murine, and Syrian hamster prion proteins, but with the present study two localized "conformational markers" could be related with single amino acid exchanges. (rcsb.org)
  • Previous studies have shown that prion proteins need a specific molecule, glycophosphoinositol (GPI), to fasten to cells in the brain and other organs. (preventdisease.com)
  • The mice began exhibiting symptoms of disease in their central nervous systems between 380 and 660 days after they were given the synthetic prion proteins. (scienceblog.com)
  • These abnormal proteins appear to convert other, normal prions to the abnormal shape. (scienceblog.com)
  • Prions are infected proteins that are misfolded and "normally present in brain cells" (Campbell and Reece, 2002). (brightkite.com)
  • Prions attach themselves to healthy proteins, corrupt the healthy proteins which inturn become prions. (brightkite.com)
  • But some recently discovered prion proteins do not seem to induce pathological changes and, in fact, may function in basic biological processes such as transcription, immune regulation, and memory formation. (cshlpress.com)
  • The contributors review the structures of prion proteins and how they adopt alternative structures and aggregate into amyloid fibrils and other insoluble complexes. (cshlpress.com)
  • Although some prion proteins feature in cellular dysfunction, others have normal physiological roles (e.g. (cshlpress.com)
  • This volume is an essential reference for biochemists, cell and molecular biologists, and all who wish to understand how prions are formed from alternatively folded, self-propagating proteins. (cshlpress.com)
  • Over the past decade, a number of proteins have been reported to possess the characteristics of PrP prions. (cshlpress.com)
  • But this was not the end of the fantastic history of the incredible protein designed prion by Prusiner, because now the investigation on neuroscience has founded prion-like proteins playing an important role in the genesis of the long-term memory. (scielo.cl)
  • Prions don't sound so bad at first blush: they're simply proteins that have the wrong shape. (bigthink.com)
  • The best analogy is that they become zombie proteins - when they come into contact with another PrP protein, they cause that protein to misfold into another prion. (bigthink.com)
  • Proteins are generally beneficial for the human body, but when they are transformed into prions, they become deadly. (sixwise.com)
  • In fact, the majority of these proteins were not known to be heat-resistant nor do they possess any prion-like domain. (microbes.info)
  • Instead of developing drugs to target abnormal proteins, it could be more efficient to try to limit the supply of normally produced prions-in essence, reducing the amount of fuel being fed into the fire. (scripps.edu)
  • First, the transient overexpression experiment found 46 proteins with prion-like behavior. (icr.org)
  • The close similarity between these new prion-like proteins and human proteins with prion-like characteristics (and their underlying genetics), which both enable the physical flexibility to fulfill a variety of roles in a cell, was not missed. (icr.org)
  • Each disease also has a particular genetic profile of the prion protein gene. (cdc.gov)
  • A prion is an infectious agent consisting of a protein that is mis-folded. (answers.com)
  • Simply put a prion is a pathogen that consists only of protein and only infect animals. (answers.com)
  • A prion can rearrange the structure of a normal protein, causing it to become a prion as well (which is why it is an infectious agent). (answers.com)
  • Prions are an infectious particle made of protein. (answers.com)
  • Prions are protein matrices that self replicate. (answers.com)
  • He continues: ''In vCJD, the normal version of prion protein, PrPc, found naturally in the brain is corrupted by infectious prions to cause disease. (psychcentral.com)
  • Using cells grown in the lab, the team looked at the effect of high and low levels of normal prion protein on the successful formation of beta amyloid, the source of Alzheimer's plaques. (psychcentral.com)
  • It appears that PrPc, the normal prion protein, exerts its beneficial effect by stopping an enzyme called beta-secretase from cutting up amyloid protein into the smaller beta-amyloid fragments needed to build plaques. (psychcentral.com)
  • The next step for our research will be to look in more detail at how the prion protein controls beta amyloid, knowledge that could be used to design anti-Alzheimer's drugs. (psychcentral.com)
  • A small section of protein turns out to be responsible for the infectious properties of prions. (technologyreview.com)
  • The book reviews advances in studies of prions, which - as considereable evidence indicates - are novel pathogens composed only of protein. (springer.com)
  • After several groups determined the genetic sequence of that protein, Prusiner realized that it was a fragment of a normal protein (prion protein or PrP), the function of which is still uncertain, which is found in healthy nerve cells. (encyclopedia.com)
  • They have gone on to argue, but not to prove, that once mutated, this protein becomes an aberrant prion, e.g. (encyclopedia.com)
  • Such de novo prion generation has previously been achieved with animal cells using a method called 'protein misfolding cyclic amplification' (PMCA), which involves repeated rounds of ultrasound and incubation. (scientificamerican.com)
  • The PRNP gene provides instructions for making a protein called prion protein (PrP). (medlineplus.gov)
  • Prusiner showed that the gene for the prion protein was present in the genome of a wide range of mammals. (sourcewatch.org)
  • The prion protein could exist in one of two different forms. (sourcewatch.org)
  • In analogy to a well known literary work, the normal [prion protein] can be compared to the friendly Dr. Jekyll and the disease causing [altered prion protein] to the dangerous Mr. Hyde, the same entity but in two different manifestations. (sourcewatch.org)
  • The pathophysiology of CJD is incompletely understood, although it is known that in persons with the disease, the normal soluble prion protein (PrP C ) is conformationally shifted into a more stable, less soluble ß-pleated protein. (mad-cow.org)
  • Limited proteolysis of PrP CJD by Western blot analysis shows four patterns of protease-resistant prion protein ( 12,13 ). (mad-cow.org)
  • Sporadic CJD may also result from the spontaneous conversion of PrP C into PrP CJD or from somatic mutation in the prion protein gene. (mad-cow.org)
  • They consist, at least in part, of a rogue isoform of the ubiquitous normal cellular prion protein. (mad-cow.org)
  • Here the authors describe a monoclonal antibody, 15B3, that can discriminate between the normal and disease-specific forms of the prion protein. (mad-cow.org)
  • They discuss models for the PrPSc-specific epitope that ensure close spatial proximity of all three15B3 segments, either by intermolecular contacts in oligomeric forms of the prion protein or by intramolecular rearrangement. (mad-cow.org)
  • Soto's team analyzed the retention of infectious prion protein and infectivity in wheat grass roots and leaves incubated with prion-contaminated brain material and discovered that even highly diluted amounts can bind to the roots and leaves. (medicalnewstoday.com)
  • Mice genetically engineered to overexpress the human prion protein (tgHu) have emerged as highly relevant models for gauging the capacity of prions to transmit to humans. (nature.com)
  • In the absence of identified external causes sCJD is considered to be a spontaneous disorder precipitated by mis-folding of the normal cellular prion protein (PrP C ) 1 . (nature.com)
  • A fundamental event in prion propagation is the conversion of the normal cellular prion protein (PrP C , which is encoded by the PRNP gene) into an abnormal disease-associated isoform (PrP Sc ) in tissues of infected individuals. (nature.com)
  • The curative properties of stem cells may rely on prions, a new study suggests, the type of protein made infamous by mad cow disease. (newscientist.com)
  • Etiopathology and Genetics (Table 1) Prion protein (PrPc) is a normal protein coded for by a gene- the human PRNP gene (PRNP) located on chromosome 20. (psu.edu)
  • Some prion protein mutations create anchorless molecules that cause Gerstmann-Sträussler-Scheinker (GSS) disease. (pnas.org)
  • To model GSS, we generated transgenic mice expressing cellular prion protein (PrP C ) lacking the glycosylphosphatidyl inositol (GPI) anchor, denoted PrP(ΔGPI). (pnas.org)
  • Here we show that the sialylation status of the infectious, disease-associated state of the prion protein (PrP Sc ) changes with colonization of secondary lymphoid organs (SLOs). (pnas.org)
  • Mammalian prions replicate by recruiting the normal cellular form of the prion protein (PrP), denoted as PrP C , and converting it into the disease-associated form, denoted as PrP Sc ( 3 ). (pnas.org)
  • This small infectious particle is a disease-causing form of a protein called cellular prion protein (PrPc). (news-medical.net)
  • A prion is composed of abnormally folded protein that causes progressive neurodegenerative conditions, with two of the most notable being Bovine spongiform encephalopathy (BSE or mad cow disease) seen in cattle and livestock and Creutzfeldt-Jakob disease (CJD) seen in humans. (news-medical.net)
  • The normal prion protein is thought to be made up of flexible coils referred to as alpha helices, but in the abnormally folded form, these helices are stretched out into densely packed structures called beta sheets. (news-medical.net)
  • Although the majority of cases occur on a sporadic basis, and rarely result from exposure to prions, such as mad cow disease, 10-15% are attributable to the presence of an autosomal dominant mutation of the prion protein gene ( PRNP ). (nature.com)
  • A prion protein gene ( PRNP ) disease-causing mutation (see molecular genetic testing, Fig. 1 and Table 3 ). (nature.com)
  • A prion is essentially an abnormally folded protein. (creation.com)
  • Where do the infectious protein particles called prions come from? (news-medical.net)
  • The meat may cause normal human prion protein to develop abnormally. (hopkinsmedicine.org)
  • The mysterious, highly infectious prions, which cause the severe destruction of the brain that characterizes "mad cow disease" and several human brain degenerative disorders, can be rendered harmless in the laboratory by a slight alternation of the three-dimensional conformation or shape of the prion protein s structure. (innovations-report.com)
  • This discovery is very interesting from a basic scientific point of view because it shows that a specific conformation of the prion protein is the infectious entity, and also that we can easily destroy the prion s infectivity by altering its shape," said Riek. (innovations-report.com)
  • Previous studies revealed that a prion s switch from a normal to the infectious form is associated with a change in the three-dimensional folded shape, or conformation, of the prion s protein structure. (innovations-report.com)
  • Building on research that identified the part of the prion protein that made a fungal prion infectious, Riek and colleagues discovered that this critical region forms a flat structure called a beta-sheet. (innovations-report.com)
  • Using a genetic engineering technique called point mutation to change one at a time each amino acid component of the prion protein, the Salk scientists created a variety of different versions of the prion to determine whether the flat shape of the beta-sheet itself was necessary for a prion to be infectious. (innovations-report.com)
  • Normal, or cellular prion protein (PrPC), is an innocuous cell-surface molecule expressed throughout the brain. (alzforum.org)
  • A Jekyll and Hyde-like conformational change in the protein turns it into a lethal infectious agent (PrPSc) that can self-propagate by catalyzing the conversion of other normal prions. (alzforum.org)
  • Prion Protein Structure. (bio.net)
  • Is there anyone out there who can give me a pointer to a good reference book/website/newsgroup where I would be able to get information on the primary, secondary, tertiary, and quaternary structures of any prion protein(s), or information on prions in general? (bio.net)
  • Prion isoforms of the prion protein (PrP), whose specific function is uncertain, are hypothesized as the cause of transmissible spongiform encephalopathies (TSEs), including scrapie in sheep, chronic wasting disease (CWD) in deer, bovine spongiform encephalopathy (BSE) in cattle (commonly known as "mad cow disease") and Creutzfeldt-Jakob disease (CJD) in humans. (wikipedia.org)
  • The protein that prions are made of (PrP) is found throughout the body, even in healthy people and animals. (wikipedia.org)
  • The normal form of the protein is called PrPC, while the infectious form is called PrPSc - the C refers to 'cellular' PrP, while the Sc refers to 'scrapie', the prototypic prion disease, occurring in sheep. (wikipedia.org)
  • UCSF scientists have demonstrated for the first time that a change in the folded shape of a prion protein changes its infectious properties -- including the prion's ability to jump "species barriers. (eurekalert.org)
  • To reconcile the existence of prion strains with the "protein-only" hypothesis of prion propagation, scientists had proposed that a single protein can misfold into multiple different infectious conformations: one for each different type of prion strain. (eurekalert.org)
  • In mammals, different strains of the same prion protein cause mad cow disease, scrapie and the related Creutzfeldt Jacob Disease (CJD), all of which lead to debilitating neurological damage known as transmissible spongiform enchephalopathy. (eurekalert.org)
  • In their laboratory at UCSF's Mission Bay campus, Weissman and his colleagues introduced misfolded forms of a yeast prion protein into normal (prion-free) yeast. (eurekalert.org)
  • The infectious agent in the prion disease is composed mainly or entirely of an abnormal conformation of a host-encoded glycoprotein called the prion protein. (medscape.com)
  • The replication of prions involves the recruitment of the normally expressed prion protein, which has mainly an alpha-helical structure, into a disease-specific conformation that is rich in beta-sheet. (medscape.com)
  • Highly divergent hypotheses have been put forward regarding the makeup of the prions, including that they consist of nucleic acid only or protein only, are lacking both protein and nucleic acid, or are a polysaccharide. (medscape.com)
  • In this study, attempts were made to characterize prion protein in urine samples from normal and scrapie-infected sheep. (psu.edu)
  • A primary target for therapy has been the conversion of the normal form of prion protein (PrPC) to its abnormal counterpart (PrPSc). (ingentaconnect.com)
  • T]he prion protein is absolutely resistant, when it is bound to a steel surface. (rense.com)
  • This means that an enzyme that can demolish the bad prion protein can entirely ignore the needed variant of that protein. (halfbakery.com)
  • 2014. Prion protein-specific antibodies that detect multiple TSE agents with high sensitivity and specificity . (wur.nl)
  • 2014. Enhanced virulence of sheep-passaged BSE is revealed by decreased polymorphism-barriers in prion protein conversion studies . (wur.nl)
  • GF BM hmmbuild HMM.ann SEED.ann #=GF SM hmmsearch -Z 57096847 -E 1000 --cpu 4 HMM pfamseq #=GF TP Domain #=GF RN [1] #=GF RM 8700211 #=GF RT NMR structure of the mouse prion protein domain PrP(121-321). (genome.jp)
  • GF RN [2] #=GF RM 9280298 #=GF RT NMR characterization of the full-length recombinant murine prion #=GF RT protein, mPrP(23-231). (genome.jp)
  • GF CC The prion protein is thought to be the infectious agent that #=GF CC causes transmissible spongiform encephalopathies, such as #=GF CC scrapie and BSE. (genome.jp)
  • It is thought that the prion protein can exist #=GF CC in two different forms: one is the normal cellular protein, and #=GF CC the other is the infectious form which can change the normal #=GF CC prion protein into the infectious form. (genome.jp)
  • It has been found that #=GF CC the prion alpha-helical domain is also found in the Doppel #=GF CC protein. (genome.jp)
  • Both teams developed methods to amplify the prions in blood samples using a technique called protein misfolding cyclic amplification (PMCA). (nih.gov)
  • Researchers have noted that Alzheimer's behaves like a slow moving version of CJD, 12, 13, 14 and according to one paper, 15 "Prions are considered a subclass of amyloids in which protein aggregation becomes self-perpetuating and infectious. (organicconsumers.org)
  • A prion is a misshapen protein that acts like an infectious agent (hence the name, which comes from the words protein and infection). (technologyreview.com)
  • The beads the team has developed are tiny magnets coated in peptoids that resemble part of the prion protein. (news-medical.net)
  • Researchers first discovered the prion protein that underlies many forms of prion disease back in 1985 but developing diagnostic tests and potential treatments have eluded them ever since. (news-medical.net)
  • The main problem has been that affected individuals have very low concentrations of the prion protein in their bodily fluids, while the normal form of the protein is abundant. (news-medical.net)
  • Not only would it have needed to be sensitive enough to isolate low levels of prions and specific enough to not generate false positives, but any potential binding agent would have had to be able to withstand the protein-degrading enzymes that circulate in the blood, explains Zuckermann. (news-medical.net)
  • The plant materials were then washed and amounts of prions were determined by protein misfolding cyclic amplification . (virology.ws)
  • The animals showed the characteristic spongiform degeneration of prion disease and accumulation of the misfolded prion protein, neither of which were present in uninfected Tg2576 mice. (alzforum.org)
  • First, the prions might cause an overload of the clearance mechanisms for misfolded protein that were already strained by Aβ accumulation. (alzforum.org)
  • The rare condition known as multiple system atrophy now appears to be caused by a prion version of alpha-synuclein , the same protein involved in Parkinson's. (sciencemag.org)
  • Kuru is a neurological infection caused by a misshapen protein or prion. (brightkite.com)
  • Prions are a native protein conformation's Mr. Hyde: They adopt a particular conformation that induces self-perpetuating protein aggregation, which can lead to devastating effects. (sciencemag.org)
  • show that effective antiviral immunity may depend on the formation of prion-like aggregates of the protein MAVS. (sciencemag.org)
  • As the aberrant prions form amyloids - aggregates of protein - in the cells, the cells die, creating holes in the brain. (scienceinschool.org)
  • However, three decades of subsequent investigations, pursued most notably by Stanley Prusiner, who was awarded the Nobel Prize in Physiology or Medicine in 1997 for his work with prions and TSEs, resulted in the wide acceptance of this 'protein-only hypothesis' w2 . (scienceinschool.org)
  • To prove that a TSE is indeed caused by the prion protein itself, the isolated, purified aberrant prions must be used to transmit the disease. (scienceinschool.org)
  • This review highlights the modern perception of anomalous folding of the prion protein and the role of chaperones therein. (biomedsearch.com)
  • This review discusses in detail our previous works that have demonstrated fundamental differences between eukaryotic and prokaryotic chaperones in the action exerted on the amyloid-like transformation of the prion protein along with the dependence of the observed effects on the functional state of the chaperone. (biomedsearch.com)
  • Washington, July 27 (ANI): Researchers have, for the first time, shown that abnormal prions - bits of infectious protein devoid of DNA or RNA that can cause fatal neurodegenerative disease - can suddenly erupt from healthy brain tissue. (thaindian.com)
  • Infectious prions, which are composed solely of protein, are classified by distinct strains, originally characterized by their incubation time and the disease they cause. (thaindian.com)
  • Mammalian cells normally produce harmless cellular prion protein (PrPC). (thaindian.com)
  • Following prion infection, the abnormal or misfolded prion protein (PrPSc) converts PrPC into a likeness of itself, by causing it to change its conformation or shape. (thaindian.com)
  • Weissmann and his colleagues in London found that when normal prion protein is coated onto steel wires and brought into contact with cultured cells, a small but significant proportion of the coated wires cause prion infection of the cells - and when transferred to mice, they continue to spawn the disease. (thaindian.com)
  • Prion disorders like Creutzfeldt-Jakob disease arise when misfolded versions of a central nervous system-dwelling protein convert its normal counterparts into harmful conformations. (eurekalert.org)
  • The NMR structures of three single-amino acid variants of the C-terminal domain of the human prion protein, hPrP(121-230), are presented. (rcsb.org)
  • 1997. Deadly conformations - Protein misfoldingin prion disease. (prezi.com)
  • 2009. The consequences of pathogenic mutations to the human prion protein. (prezi.com)
  • Instead, the brains contained large accumulations of prion protein plaques trapped outside blood vessels in a disease process called cerebral amyloid angiopathy. (preventdisease.com)
  • The usual prion protein cell anchor was also missing in those cases. (preventdisease.com)
  • The presence or absence of the prion protein anchor appears to determine which form of disease develops. (preventdisease.com)
  • demonstrated that they were able to replicate ruminant prions in vitro with a protein-PCR-like test. (wur.nl)
  • used the PCMA method (protein misfolding cyclic amplification, sort of protein-PCR) to measure the formation speed of prions at the molecular level. (wur.nl)
  • Scientists have produced a prion protein that can trigger the development of a neurological disorder in mice that is similar to "mad cow" disease, according to a new study supported by the National Institute on Aging (NIA), a part of the National Institutes of Health. (scienceblog.com)
  • For the study, Dr. Prusiner and his colleagues produced prion protein fragments in bacteria, folded them into larger protein structures called amyloid fibrils, and then injected them into the brains of susceptible mice. (scienceblog.com)
  • The amyloid form of the prion protein, which is thought to cause prion disease, was also found in the brains of the diseased mice. (scienceblog.com)
  • The disorder seems to be distinct from that caused by other known strains of prions, suggesting that the synthetic prion didn't merely activate a pre-existing prion in these mice and that the synthesized prion protein itself is sufficient to make infectious and disease-causing prions. (scienceblog.com)
  • Our studies show that stimulation of the immune system is an important therapeutic target for the prion disease, as well as for other neurodegenerative illnesses characterized by abnormal protein conformations, such as Alzheimer's disease," concluded study author Thomas Wisniewski, MD. (scienceblog.com)
  • Prions are transmissible particles that are devoid of nucleic acid and seem to be composed exclusively of a modified protein (PrP Sc ). (sciencemag.org)
  • The normal, cellular prion protein (PrP C ) is converted into PrP Sc through a posttranslational process during which it acquires a high β-sheet content. (sciencemag.org)
  • But whenever a PrP protein is made in the wrong shape, it turns into a proteinaceous infectious particle, or a prion. (bigthink.com)
  • First, the PRNP gene (which produces the PrP protein) can be mutated, making it more likely for the associated protein to fold into a prion. (bigthink.com)
  • The common pathogen to all TSEs is termed prion and is believed to consist solely or primarily of the disease-associated isoform (PrP Sc ) of the cellular prion protein (PrP C ). PrP C is a highly conserved, GPI-anchored sialoglycoprotein encoded by the single-copy Prnp gene. (intechopen.com)
  • How does the prion protein clump? (microbes.info)
  • The cellular prion protein (PrPc) is a glycoprotein anchored to the plasma membrane by GPI (Glycosyl-phosphatidylinositol). (usp.br)
  • Scientists from The Scripps Research Institute have determined for the first time that prions, bits of infectious protein devoid of DNA or RNA that can cause fatal neurodegenerative disease, are capable of Darwinian evolution. (scripps.edu)
  • The study from Scripps Florida in Jupiter shows that prions can develop large numbers of mutations at the protein level and, through natural selection, these mutations can eventually bring about such evolutionary adaptations as drug resistance, a phenomenon previously known to occur only in bacteria and viruses. (scripps.edu)
  • These breakthrough findings also suggest that the normal prion protein-which occurs naturally in human cells-may prove to be a more effective therapeutic target than its abnormal toxic relation. (scripps.edu)
  • Now, this adaptability has moved one level down-to prions and protein folding-and it's clear that you do not need nucleic acid for the process of evolution. (scripps.edu)
  • Mammalian cells normally produce cellular prion protein or PrP C . During infection, abnormal or misfolded protein-known as PrP Sc -converts the normal host prion protein into its toxic form by changing its conformation or shape. (scripps.edu)
  • It was generally thought that once cellular prion protein was converted into the abnormal form, there was no further change," Weissmann said. (scripps.edu)
  • Weissmann and his colleagues have shown some 15 years ago that genetically engineered mice devoid of the normal prion protein develop and function quite normally (and are resistant to prion disease! (scripps.edu)
  • It will likely be very difficult to inhibit the production of a specific natural protein pharmacologically," Weissmann said, "You may end up interfering with some other critical physiological process, but nonetheless, finding a way to inhibit the production of normal prion protein is a project currently being pursued in collaboration with Scripps Florida Professor Corinne Lasmezas in our department. (scripps.edu)
  • Fabrizio Tagliavini of the Carlo Besta National Neurological Institute in Milan, Italy, and his colleagues thus set out to test the antibiotic's prion-stopping power in animals infected with so-called transmissible spongiform encephalopathies. (scientificamerican.com)
  • Rogue prion -specific epitope defined by a monoclonal antibody Prions are infectious particles causing transmissible spongiform encephalopathies (TSEs). (mad-cow.org)
  • The term 'prion' is derived from proteinacious infectious particle and refers to the pathogen that causes transmissible spongiform encephalopathies (TSEs). (news-medical.net)
  • CDC does not currently offer information on every prion disease listed below. (cdc.gov)
  • Variant Creutzfeldt-Jakob disease (vCJD) is a prion disease that was first described in 1996 in the United Kingdom. (cdc.gov)
  • There is now strong scientific evidence that the agent responsible for the outbreak of prion disease in cows, bovine spongiform encephalopathy (BSE or 'mad cow' disease), is the same agent responsible for the outbreak of vCJD in humans. (cdc.gov)
  • Scrapie is an infectious disease in which prions destroy the animal's brain, rather like BSE. (medicalnewstoday.com)
  • The incubation period - the time it takes for the disease to break out - is exceedingly short even after the prions have persisted in the soil for 29 months. (medicalnewstoday.com)
  • Excretion/secretion occurs through long asymptomatic periods of disease development and from sheep with a range of PRNP genotypes, including those with limited lymphoreticular involvement in prion replication (Gough et al. (nottingham.ac.uk)
  • New research suggests the normal role of prions help to prevent the plaques that build up in the brain to cause Alzheimer's disease. (psychcentral.com)
  • Prions, they observed, had never been shown to cause disease. (encyclopedia.com)
  • But findings published online this week by the Proceedings of the National Academy of Sciences suggest that the common antibiotic tetracycline renders prions susceptible to digestion by enzymes and helps staves off disease in hamsters. (scientificamerican.com)
  • Because the drug seems to weaken the prions' protective armor, the authors conclude that "tetracyclines are immediate candidates for prion inactivation in potentially contaminated products and prevention strategies relevant to acquired forms of disease. (scientificamerican.com)
  • What we were doing was trying to develop a very sensitive assay for prion detection on a metal surface, so we could use that in prion decontamination,' says co-author John Collinge, who heads up the Department of Neurodegenerative Disease at University College London. (scientificamerican.com)
  • Crucially, when transferred to mice, the new prions caused disease with different characteristics from that produced by the scrapie prions normally used in the laboratory. (scientificamerican.com)
  • Prion disease represents a group of conditions that affect the nervous system in humans and animals. (medlineplus.gov)
  • The signs and symptoms of prion disease typically begin in adulthood and worsen with time, leading to death within a few months to several years. (medlineplus.gov)
  • Although the exact prevalence of prion disease is unknown, studies suggest that this group of conditions affects about one person per million worldwide each year. (medlineplus.gov)
  • Between 10 and 15 percent of all cases of prion disease are caused by mutations in the PRNP gene. (medlineplus.gov)
  • Because they can run in families, these forms of prion disease are classified as familial. (medlineplus.gov)
  • The loss of these cells creates microscopic sponge-like holes (vacuoles) in the brain, which leads to the signs and symptoms of prion disease. (medlineplus.gov)
  • The other 85 to 90 percent of cases of prion disease are classified as either sporadic or acquired. (medlineplus.gov)
  • People with sporadic prion disease have no family history of the disease and no identified mutation in the PRNP gene. (medlineplus.gov)
  • Sporadic forms of prion disease include sporadic Creutzfeldt-Jakob disease (sCJD), sporadic fatal insomnia (sFI), and variably protease-sensitive prionopathy (VPSPr). (medlineplus.gov)
  • Acquired prion disease results from exposure to PrP Sc from an outside source. (medlineplus.gov)
  • For example, variant Creutzfeldt-Jakob disease (vCJD) is a type of acquired prion disease in humans that results from eating beef products containing PrP Sc from cattle with prion disease. (medlineplus.gov)
  • Another example of an acquired human prion disease is kuru, which was identified in the South Fore population in Papua New Guinea. (medlineplus.gov)
  • Rarely, prion disease can be transmitted by accidental exposure to PrP Sc -contaminated tissues during a medical procedure. (medlineplus.gov)
  • This type of prion disease, which accounts for 1 to 2 percent of all cases, is classified as iatrogenic. (medlineplus.gov)
  • Familial forms of prion disease are inherited in an autosomal dominant pattern, which means one copy of the altered PRNP gene in each cell is sufficient to cause the disorder. (medlineplus.gov)
  • The sporadic, acquired, and iatrogenic forms of prion disease, including kuru and variant Creutzfeldt-Jakob disease, are not inherited. (medlineplus.gov)
  • Dr. Stanley B. Prusiner gave the name "prion" to the substance he and his colleagues isolated in 1982 from diseased hamster brains, which by itself could transmit the neurological disease scrapie (first identified in sheep) to other animals. (sourcewatch.org)
  • Without the genetic information that allows everything from viruses to human cells to replicate, scientists wondered, how could prions multiply and cause disease? (sourcewatch.org)
  • This suggests that plants may play an important role in environmental prion contamination and the horizontal transmission of the disease. (medicalnewstoday.com)
  • Although Bovine Spongiform Encephalopathy (BSE) is the cause of variant Creutzfeldt Jakob disease (vCJD) in humans, the zoonotic potential of scrapie prions remains unknown. (nature.com)
  • In 1996, a new human prion disease, referred as variant CJD (vCJD), was observed in UK individuals. (nature.com)
  • What is known is that prions that become misshapen, through some unknown process, can result in BSE (bovine spongiform encephalopathy) - mad cow disease - and its equivalents in other animals. (newscientist.com)
  • Remarkably, disease from ill Tg(PrP,ΔGPI) mice transmitted to mice expressing wild-type PrP C , indicating the spontaneous generation of prions. (pnas.org)
  • The most common human prion disease is Creutzfeldt-Jakob Disease (CJD), a rare, rapidly progressive neurodegenerative disorder. (kingcounty.gov)
  • Three cases of prion disease were reported in 2015. (kingcounty.gov)
  • [ 118 ] and the authors have demonstrated that a chelator, D-penicillamine, which selectively chelates copper, delays the onset of prion disease in infected mice. (medscape.com)
  • Single base pair changes, or the insertion of one or more multiples of a 24 base pair repeat segment, make up the known sequence alterations of PRNP associated with genetic prion disease. (nature.com)
  • The common polymorphic codon 129 of PRNP also plays an important and complex role in risk and phenotype of sporadic and genetic prion disease. (nature.com)
  • In addition, a Huntington disease phenocopy known as Huntington disease like-1 (HDL-1) has been described in a family with genetic prion disease ( Tables 1 and 2 ). (nature.com)
  • Schematic representation of the PRNP gene, with the major polymorphisms and prion disease-associated mutations. (nature.com)
  • It should be emphasized that these tests have been best studied and are most helpful in the diagnosis of nongenetic prion disease (i.e., sporadic CJD). (nature.com)
  • Therefore, reliance on these studies for the diagnosis of genetic prion disease is cautioned. (nature.com)
  • So-called 'mad cow disease' is just one example of the syndromes that can be caused by prions. (creation.com)
  • Prions have been among the most controversial of infectious disease agents. (nih.gov)
  • We know that Japan has had prion disease, as well as cases of MUTATED stain prion, as did Italy. (rense.com)
  • Why, in the 'name of good sense' would we want to buy rendered products from countries that have prion disease, especially, prion disease that has been mutated and novel? (rense.com)
  • For example, prions have been found in the urine and blood of human victims of Creutzfeldt Jakob Disease. (rense.com)
  • A team of researchers from the University of British Columbia and the Vancouver Coastal Health Research Institute have found a key link between prions and the neurodegenerative disease ALS (Amyotrophic Lateral Sclerosis), also known as Lou Gehrig's disease. (news-medical.net)
  • On the positive side, recent findings suggest that therapeutic strategies modulating microglial activation and function may have merit in prion disease. (jci.org)
  • Moreover, studies on the role of microglia in prion disease could deepen our understanding of neuroinflammation in a broad range of neurodegenerative disorders. (jci.org)
  • Microglial activation in prion disease. (jci.org)
  • This volume provides an in-depth overview from world experts on prion disease. (springer.com)
  • The most common form of prion disease that affects humans is Creutzfeldt-Jakob disease (CJD). (hopkinsmedicine.org)
  • What causes prion disease? (hopkinsmedicine.org)
  • The existence and implications of subclinical forms of prion disease are discussed. (nih.gov)
  • In humans, prions are believed to be the cause of Creutzfeldt-Jakob disease (CJD), its variant (vCJD), Gerstmann-Sträussler-Scheinker syndrome (GSS), fatal familial insomnia (FFI), and kuru. (wikipedia.org)
  • An investigational approach to sifting infectious prions from donated blood could help quell fears, focused in Britain, about the possible spread by transfusion of variant Creutzfeldt-Jakob disease, researchers here reported. (organicconsumers.org)
  • Like prions that cause mammalian disease, the prions in yeast naturally exist in several different forms or strains. (eurekalert.org)
  • Spongiform change in prion disease. (medscape.com)
  • Thousands of compounds have been screened for anti-prion effect, and yet of those that have effect in vitro, very few show effect in vivo, especially if administered in the later stages of disease. (ingentaconnect.com)
  • Colin Lowry, cell biologist and Associate Editor of 21st Century Science & Technology magazine, was interviewed on Feb. 12 on the danger of bovine spongiform encephalopathy - BSE, or mad cow disease - and the little-known science of prions. (rense.com)
  • So, it is potentially possible, that if they are eating from the same sources - and the salivary glands are loaded with prions - that they may be able to somehow spread the disease through their own salivation, onto the food the other sheep eat. (rense.com)
  • I've just finished reading an article in a very recent SCIENTIFIC AMERICAN, and am now convinced that prions pose as much a long-term and insidious threat to humanity as any other disease in history. (halfbakery.com)
  • 2014. Prion disease tempo determined by host-dependent substrate reduction . (wur.nl)
  • The sequence of amino acid that makes up PrP can fold into at least an alpha-helices, cellular PrP and a disease causing form called beta-pleated sheets called prion PrP . (omninoggin.com)
  • Prion PrP leads to prion disease such as the mad cow disease or bovine spongiform encephalitis, scrapie, kuru, Creutzfeldt-Jakob disease, among others. (omninoggin.com)
  • These "silent" carriers have small amounts of prions in their bloodstreams and can transmit the disease to others via blood transfusions. (nih.gov)
  • Detection of prions in blood from patients with variant Creutzfeldt-Jakob disease. (nih.gov)
  • Detection of prions in the plasma of presymptomatic and symptomatic patients with variant Creutzfeldt-Jakob disease. (nih.gov)
  • For a number of years now, researchers have theorized and found evidence suggesting Alzheimer's disease may in fact be a type of prion-based disease, 7 , 8 , 9 capable of being contracted via meat 10 and transmitted via certain invasive medical procedures . (organicconsumers.org)
  • Some of these samples were contaminated with prions that caused certain patients to develop Creutzfeldt-Jakob disease (CJD), a rare and fatal brain disorder. (organicconsumers.org)
  • TDP-43 behaves like the prions responsible for the brain destruction seen in Mad Cow and Chronic Wasting Disease. (organicconsumers.org)
  • The assay was developed by researchers at Novartis and prion disease expert Adriano Aguzzi, senior author of the study. (news-medical.net)
  • This assay could also be modified to test deer and elk for chronic wasting disease (CWD), a prion disease that is considered as a global epidemic in these animals. (news-medical.net)
  • Chronic wasting disease is a prion disease of cervids (deer, elk, moose) that is potentially a threat to human health. (virology.ws)
  • A concern is that prions of chronic wasting disease could be transmitted to cows grazing in pastures contaminated by cervids. (virology.ws)
  • To determine whether prions can enter plants, wheat grass roots and leaves were exposed to brain homogenates from hamsters that had died of prion disease. (virology.ws)
  • All animals fed infected plants or brain homogenates succumbed to prion disease. (virology.ws)
  • There is no species barrier to prion disease. (virology.ws)
  • Amyloid and Prions-Co-Conspirators in Disease? (alzforum.org)
  • Soto and colleagues injected infective prions into an AD mouse model, and found an exacerbation of pathology and an accelerated onset of disease. (alzforum.org)
  • He found that prion disease progressed to clinical symptoms and death much faster in the Tg2576 mice compared to wild-type. (alzforum.org)
  • In support of the latter possibility, the researchers found prions in amyloid deposits in the injected transgenic mice, a situation they did not find in animals with only amyloid plaques or prion disease. (alzforum.org)
  • In addition, there are scattered reports of co-occurring Aβ and prion pathology in human disease, but just how common the situation might be is unknown. (alzforum.org)
  • And he and his co-workers have just identified a new prion disease (the first in many years). (sciencemag.org)
  • That mode of therapy came to a gravel-spraying halt in about 1985, when the dangers of prion transmission had become clear, but the latency time is so terrifyingly long and unpredictable that people are still manifesting with the disease. (sciencemag.org)
  • So what does one do about a prion disease? (sciencemag.org)
  • Since the epidemic of 'mad cow disease' in the 1980s and 90s, and the emergence of its human equivalent, variant Creutzfeld-Jacob disease, there has been a great deal of research into prions, the causative agents. (scienceinschool.org)
  • This has a domino effect whereby a small number of aberrant prions can affect many normal ones and eventually lead to disease. (scienceinschool.org)
  • The most worrying prion strain is the one that causes vCJD - a form of mad cow disease that has crossed the species barrier to infect humans (see box below). (scienceinschool.org)
  • Surprisingly, according to the new research, wires coated with uninfected brain homogenate could also initiate prion disease in cell culture, which was transmissible to mice. (thaindian.com)
  • Our study offers experimental proof that prions can in fact originate spontaneously, and shows that this event is promoted by contact with steel surfaces," said Charles Weissmann, chair of Scripps Florida's Department of Infectology, who led the study with John Collinge, head of the Department of Neurodegenerative Disease at UCL Institute of Neurology. (thaindian.com)
  • The following NMHI members and colleagues study Alzheimer's disease, dementia and prion disease. (ualberta.ca)
  • For more information about NMHI research in Alzheimer's disease, dementia and prion disease, please check out this video featuring Dr. Jack Jhamands NMHI member . (ualberta.ca)
  • Although Creutzfeldt-Jakob disease was known to be transmissible through corneal transplants and contaminated surgical tools that contacted brain or nervous system tissue, scientists have found scant evidence for misfolded prions residing in other regions of the body. (eurekalert.org)
  • Here, Christina Orru and colleagues used a highly sensitive detection method called RT-QulC to search for infectious prions in skin samples from 23 Creutzfeldt-Jakob disease patients, as well as 15 individuals with unrelated neurological disorders. (eurekalert.org)
  • They found infectious prions in at least one skin sample from all Creutzfeldt-Jakob disease patients tested, most commonly in biopsies taken from the area near the ear, whereas none of the people without Creutzfeldt-Jakob disease tested positive. (eurekalert.org)
  • Notably, prion amounts detected in skin samples were roughly 1,000 to 100,000 less than found in brain tissue, and a less sensitive detection method only detected prions in skin samples from five Creutzfeldt-Jakob disease patients. (eurekalert.org)
  • Inoculations of skin from two Creutzfeldt-Jakob disease patients also lead to prion disease in two different mouse models. (eurekalert.org)
  • The studies, carried out by UC San Diego and UC San Francisco scientists in collaboration with a team a the National Institutes of Health (NIH), are reported in mBio , in a paper titled, " Prion seeds distribute throughout the eyes of sporadic Creutzfeldt-Jakob disease patients . (genengnews.com)
  • CJD is the most common prion disease in humans, and is classified as sporadic, familial, or iatrogenic (caused by a medical treatment or procedure). (genengnews.com)
  • The researchers saw signs typical of prion disease, including weight loss, lack of grooming, gait abnormalities and inactivity. (preventdisease.com)
  • But when they examined the brain tissue, they didn't find the sponge-like holes in and around nerve cells typical of prion disease. (preventdisease.com)
  • The results are similar to findings from 2 newly reported cases of the human prion disease known as Gerstmann-Straussler-Scheinker syndrome. (preventdisease.com)
  • Together, these studies represent a new mechanism of prion disease brain damage. (preventdisease.com)
  • If scientists can find an inhibitor for the new form of prion disease, Chesebro says, they might be able to use the same inhibitor to treat similar types of damage in Alzheimer's disease. (preventdisease.com)
  • We accept referrals for all undiagnosed neurological conditions if there is a suspicion of prion disease. (uclh.nhs.uk)
  • In some cases, the structure of prions can change into a disease-causing form. (scienceblog.com)
  • Creutzfeldt-Jakob disease (CJD) is a neurodegenerative brain disorder otherwise known as a prion disease. (edu.au)
  • Prion disease is a fatal brain disease manifested through failure of muscle control and dementia. (scienceblog.com)
  • Prion disease in humans (Creutzfeldt-Jakob disease) is extremely rare and is most likely transmitted through exposure to BSE-infected beef or through a surgically acquired infection. (scienceblog.com)
  • There is no effective form of therapy for prion disease. (scienceblog.com)
  • Written and edited by experts in the field, this collection from Cold Spring Harbor Perspectives in Biology examines the expanding roles of prions in health and disease. (cshlpress.com)
  • Aggregation and Prion-Like Properties of Misfolded Tumor Suppressors: Is Cancer a Prion Disease? (cshlpress.com)
  • From the scrapie of the sheep to the bovine spongiform encephalitis, and from the kuru to the Creutzfeldt-Jakob disease, tenacious investigators searched for the mysterious agent of these neurological disorders, till Stanley Prusiner discovered and described the prion in the eighties, wining the Nobel Prize in 1997. (scielo.cl)
  • Bovine spongiform encephalopathy (BSE) and human Creutzfeldt-Jakob disease (CJD) are among the most notable central nervous system degenerative disorders caused by prions. (sciencemag.org)
  • Curiously, the most famous case of a prion disease outbreak happened in a cannibalistic tribe in Papua New Guinea. (bigthink.com)
  • These prions were the infectious agents hiding in the brains of the Fore people's dead ancestors and are ultimately the cause of their deadly disease. (bigthink.com)
  • Scientists refer to this condition as prion disease, or transmissible spongiform encephalopathy (TSE) due to the sponge-like appearance of the affected brains. (bigthink.com)
  • Kuru is one type of prion disease, but this class of maladies also includes mad cow disease, fatal familial insomnia, and Creutzfeldt-Jakob disease. (bigthink.com)
  • This image depicts a cow's brain affected by mad cow disease, a kind of prion disease. (bigthink.com)
  • There are three ways one can "catch" a prion disease. (bigthink.com)
  • Finally, one can ingest prions, as is the case with kuru or mad cow disease. (bigthink.com)
  • In fact, a recent study found a new form of prion disease that does not cause the typical sponge-like brain damage common to TSEs. (sixwise.com)
  • Weissmann notes that the findings have implications for the development of therapeutic targets for prion disease. (scripps.edu)
  • Similar illnesses in animals like chronic wasting disease in deer and mad cow disease in cattle are also spread by prions. (icr.org)
  • Although famously transmitted by the ingestion of infected meats, prions are also thought to arise spontaneously in a tiny fraction of humans and other animals. (scientificamerican.com)
  • We can reproduce in a system in a lab what people believe is happening in animals and humans,' says co-author Charles Weissmann, who is currently studying prion biology at Scripps Florida in Jupiter. (scientificamerican.com)
  • The serial transmission of different scrapie isolates in these mice led to the propagation of prions that are phenotypically identical to those causing sporadic CJD (sCJD) in humans. (nature.com)
  • Riek and his colleagues used a fungus as a model system because its prions are easier to isolate and work with than are the prions from humans and other mammals. (innovations-report.com)
  • Humans poisoned by prions can now be absolutely, positively identified. (halfbakery.com)
  • Therefore it is possible that prions excreted by deer could pass on to other animals, such as grazing cows, or even humans consuming contaminated plants (illustrated - image credit ). (virology.ws)
  • There is now considerable concern that bovine prions may have been passed to humans, resulting in a new form of CJD. (sciencemag.org)
  • The existence of different prion strains has been one of the most fascinating and puzzling features of prion biology," said Jonathan Weissman, PhD, a Howard Hughes Medical Institute investigator and professor of cellular and molecular pharmacology at UCSF. (eurekalert.org)
  • Prion PrP induces the normal cellular PrP into a prion PrP by changing the shape of the cellular PrP. (omninoggin.com)
  • Researchers also found that plants can uptake prions from contaminated soil and transport them to different parts of the plant, which can act as a carrier of infectivity. (medicalnewstoday.com)
  • It s a fantastic system to study the structural components of prions and measure infectivity," Riek said. (innovations-report.com)
  • Using the Scrapie Cell Assay to measure infectivity of prion-coated wires, the team observed several unexpected instances of infectious prions in control groups where metal wires had been exposed only to uninfected normal mouse brain tissue. (thaindian.com)
  • Our findings support the World Health Organization classification of eye components as having high prion infectivity and have implications for patient safety," they noted. (genengnews.com)
  • The discovery of prion infection has an interesting history, though beyond the scope of this article. (creation.com)
  • However, the molecular mechanisms underlying the microglial response to prion infection are largely unknown. (jci.org)
  • At an early stage of prion infection and PrP Sc aggregation, microglia are activated by PrP Sc . (jci.org)
  • The infection is spread through a chain reaction like process that begins when the first abnormal prion "tags" a prion that has a normal conformation and forces it to adopt the abnormal prion shape. (innovations-report.com)
  • 2014. Role of the goat K222-PrPC polymorphic variant in prion infection resistance . (wur.nl)
  • When deer are fed prions they excrete them in the feces before developing clinical signs of infection, and prions can also be detected in deer saliva. (virology.ws)
  • RIG-I induced formation of MAVS prion-like fibrils in response to viral infection. (sciencemag.org)
  • Previous research showed that prions bind readily to these types of surfaces and can initiate infection with remarkable efficiency. (thaindian.com)
  • O prion celular (PrPc) é uma glicoproteína ligada à membrana plasmática por uma âncora de GPI (glycosylphosphatidylinositol). (usp.br)
  • In the current study, Dr. Rohwer and colleagues looked at the ability of affinity resin chromatography to remove infectious prion particles from the blood of hamsters infected with scrapie. (organicconsumers.org)
  • Prions are pro teinaceous in fective particles. (omninoggin.com)
  • Prions, the pathogens that cause scrapie in sheep, can survive in the ground for several years, as researchers have discovered. (medicalnewstoday.com)
  • Among the myriad of things that can afflict us, prions remain one of the creepiest pathogens out there. (gizmodo.com.au)
  • Prions are proteinaceous infectious agents, not conventional pathogens. (pnas.org)
  • Thus, prions may use strategies similar to other pathogens to camouflage themselves from the immune system, facilitating host invasion. (pnas.org)
  • Prions lack nucleic acids and are not conventional pathogens. (pnas.org)
  • Prions are also unique in that they do not contain nucleic acid , unlike bacteria, fungi, viruses and other pathogens. (news-medical.net)
  • Prions are therefore resistant to procedures that destroy pathogens by breaking down nucleic acid. (news-medical.net)
  • Subviral Pathogens of Plants and Animals: Viroids and Prions is organized into four parts consisting of a total of 20 chapters that discuss the nature of subviral pathogens of plants and animal. (elsevier.com)
  • Viruses, viroids, and prions are all acellular pathogens. (omninoggin.com)
  • Prions are pathogens without doubt, but could we call them parasites? (omninoggin.com)
  • Can you name the Virus and Prion Pathogens? (sporcle.com)
  • The summary table below, of what the two new anti-prion antibodies immuno-precipitate, is based on the highly compressed text, gel legends, illegible fax images, faulty memory of citation content, and guesswork. (mad-cow.org)
  • So, with respect to anti-prion pills, any prions that happen to become part of the diet can be destroyed before they reach the brain. (halfbakery.com)
  • Using this method, the scientists were able to detect more than a billion-fold dilution of prions using an anti-prion antibody. (nih.gov)
  • The researchers considered three explanations for the exacerbation of amyloid pathology by the prions. (alzforum.org)
  • These are not seen in other patients who have had growth hormone therapy from other sources, not seen in another cohort of patients with other prion conditions, and none of these eight patients had any of the known genetic predispositions to amyloid deposition. (sciencemag.org)
  • What will be important now will be distinguishing whether this low abundance does exist, or whether the process induces the spontaneous generation of prions,' says Claudio Soto, an expert in neurodegenerative disorders at the University of Texas Medical Branch in Galveston who was not involved in the work. (scientificamerican.com)
  • However, there's still a lot of work to be done in looking at levels of prions in the human system and how these may alter as we age. (psychcentral.com)
  • While the presence of Aβ did not seem to affect the extent of prion-driven spongiform degeneration, it did increase the levels of prions that could be measured in brain tissue. (alzforum.org)
  • But distribution and levels of prions in the eye were unknown. (genengnews.com)
  • Prions readily bind to steel wires, which can thus be used to detect the presence of prions, as well as to infect brains in laboratory studies. (scientificamerican.com)
  • however the presence of prions in such wastes is uncertain (EPA 2001). (rense.com)
  • Barley grass plants were grown on soil that had been mixed with hamster brain homogenate, and then 1-3 weeks later, stem and leaves were assayed for the presence of prions. (virology.ws)
  • Likewise, the presence of prions increased brain inflammation and Aβ deposition. (alzforum.org)
  • The authors conclude that the presence of prions leads to a dramatic acceleration in the misfolding, aggregation, and cerebral accumulation of Aβ, and vice versa. (alzforum.org)
  • Prions are different because they do not infect and replicate in the same way that viruses do. (answers.com)
  • Prions have neither machinery to replicate themselves, nor code to hijack the machinery of the cell. (creation.com)
  • There is still a veil of mystery around prions and exactly how they replicate, cross the blood-brain barrier and cross the species barrier - i.e. infect different species of host. (scienceinschool.org)
  • Now we know that the abnormal prions replicate, and create variants, perhaps at a low level initially. (scripps.edu)
  • The distinctive histopathological pattern elicited by the spontaneous prions excludes contamination with RML [Rocky Mountain Laboratory] or other mouse-adapted scrapie strains used by us as a cause for these mouse transmissions. (scientificamerican.com)
  • On the basis of the transmission features in conventional mice (incubation periods, distribution of the lesions in the brain), early transmission experiments described a considerable diversity of the scrapie agents with up to 20 prion strains reportedly identified 8 . (nature.com)
  • Despite converging evidence that scrapie is caused by a variety of prion strains, there is at this stage no comprehensive description of their diversity. (nature.com)
  • A News and Views commentary in Nature on the two research findings concludes that the work firmly establishes the link between different prion forms and different prion strains. (eurekalert.org)
  • Different strains of the mammalian prion play important roles in determining the degree to which a prion is pathogenic. (eurekalert.org)
  • Studying the possible link between mammalian prion shape and strains has proven very difficult, but three different prions have also been identified in yeast, a powerful model in research aimed at understanding human genetic mechanisms. (eurekalert.org)
  • The challenge now is to understand what distinguishes the different structures in the different prion strains, and how these different structures change a prion's properties -- including how dangerous they are. (eurekalert.org)
  • To confirm the findings and to explore the issue of evolution of drug resistance, Weissmann and his colleagues used the drug swainsonine or swa, which is found in plants and fungi, and has been shown to inhibit certain prion strains. (scripps.edu)
  • In earlier studies, transgenic (Tg) mice expressing low levels of PrP(ΔGPI) did not develop signs of spontaneous neurologic illness, but harbored large amyloidogenic PrP(ΔGPI) aggregates in the brain after exposure to prions ( 6 , 7 ). (pnas.org)
  • Prion aggregates are stable, and this structural stability means that prions are resistant to denaturation by chemical and physical agents: they cannot be destroyed by ordinary disinfection or cooking. (wikipedia.org)
  • In a typical experiment, they report, wires were placed with brain homogenate from either uninfected mouse brains or brains infected with scrapie prions. (scientificamerican.com)
  • Here we show that a panel of sheep scrapie prions transmit to several tgHu mice models with an efficiency comparable to that of cattle BSE. (nature.com)
  • These results demonstrate that scrapie prions have a zoonotic potential and raise new questions about the possible link between animal and human prions. (nature.com)
  • Stanley B. Prusiner, editor of this volume, was awarded the 1997 Nobel Prize in Physiology and Medicine for his pioneering discovery of prions. (springer.com)
  • Prusiner cited this evidence when he proposed the prion model in 1982. (encyclopedia.com)
  • Prusiner wrote in the article: 'because the novel properties of the scrapie agent distinguish it from viruses, plasmids, and viroids, a new term 'prion' was proposed to denote a small proteinaceous infectious particle which is resistant to inactivation by most procedures that modify nucleic acids. (news-medical.net)
  • UCSF's Stanley Prusiner, MD, received the 1997 Nobel Prize in Physiology or Medicine for the discovery of prions and the underlying principles of their mode of action. (eurekalert.org)
  • [ 5 ] Prusiner introduced the term prion to indicate that scrapie is related to a proteinaceous infectious particle (PrP). (medscape.com)
  • Prusiner received the 1997 Nobel Prize in physiology or medicine for his discovery of prions. (scienceblog.com)
  • They have treated diseased brain tissue with detergents and centrifuges and harvested the encrusted, suspect prion. (encyclopedia.com)
  • Now, a London-based team reports observing prions appearing from healthy mouse brain tissue (the results were detailed online July 26 in Proceedings of the National Academy of Sciences ). (scientificamerican.com)
  • Despite this, healthy, uninfected brain cells still tested positive for prions at low rates. (scientificamerican.com)
  • This result suggests that interactions between PrP C and polyanions found naturally in the brain may contribute to spontaneous prion formation. (nih.gov)
  • The BSE prions concentrate in an animal's brain and spinal cord, but they been detected only in sheep blood at low concentrations. (rense.com)
  • It's caused by eating human brain tissue contaminated with infectious prions. (hopkinsmedicine.org)
  • Most prion infections begin when the normal shape, for reasons unknown, spontaneously changes into the infectious form that kills brain cells. (innovations-report.com)
  • Possibly those enzymes can also circulate in the blood and eliminate prions in the brain, too. (halfbakery.com)
  • When living wheat grass leaves were sprayed with a 1% hamster brain homogenate, prions could attach to the leaves and be detected for 49 days. (virology.ws)
  • To determine if prions in plants could infect animals, plants were exposed to brain homogenates, washed thoroughly, and then fed to hamsters. (virology.ws)
  • It has been proposed that these events reflect rare, spontaneous formation of prions in brain. (thaindian.com)
  • Weissmann noted that an alternative interpretation of the results is that infectious prions are naturally present in the brain at levels not detectable by conventional methods, and are normally destroyed at the same rate they are created. (thaindian.com)
  • Used to analyze the CJD patient eyes, the assay detected abnormal prions in multiple ocular tissues, with the highest seed levels-which in some cases were not much lower than those in the brain-found in the retina. (genengnews.com)
  • The abnormal prions then clump together, which researchers believe may lead to neuron loss and brain damage. (sixwise.com)
  • In the first part of the study, Weissmann and his colleagues transferred prion populations from infected brain cells to culture cells. (scripps.edu)
  • When transplanted, cell-adapted prions developed and out-competed their brain-adapted counterparts, confirming prions' ability to adapt to new surroundings, a hallmark of Darwinian evolution. (scripps.edu)
  • When returned to brain, brain-adapted prions again took over the population. (scripps.edu)
  • To distinguish this pathogen from viruses and viroids, the term "prion" was introduced to emphasize its proteinaceous and infectious nature. (springer.com)
  • In order to see where viruses, viroids and prions fit into the scheme of life, we need to know what life is and what the properties of life are. (brightkite.com)
  • Two other cases -- identified after death and reported two years ago -- were previously identified among 66 people who got blood transfusions from donors who subsequently developed vCJD, according to Stephen Wroe, M.D., of the National Prion Clinic at the National Hospital for Neurology and Neurosurgery in London. (organicconsumers.org)
  • Our National Prion Clinic (NPC)'s multidisciplinary team comprises consultant neurologists, clinical research fellows and clinical nurse specialists. (uclh.nhs.uk)
  • Characterization of spontaneously generated PrP(ΔGPI) prions upon passage in Tg8015/ Prnp 0/0 and Tg4053 mice. (nih.gov)
  • Different phenotypes were observed biochemically following parallel transmission of spontaneously generated prions into both Tg8015/ Prnp 0/0 and Tg4053 mice. (nih.gov)
  • A research team at Dartmouth Medical School led by Dr. Surachai Supattapone reported in the June 5, 2007, issue of Proceedings of the National Academy of Sciences that they came upon a way to generate infectious prions spontaneously from noninfectious components. (nih.gov)
  • Prions can form spontaneously as well, though this is fairly rare. (bigthink.com)
  • These fungal prions have been studied extensively to provide clues as to how prions affect mammals, although fungal prions are not harmful to their host. (news-medical.net)
  • It has been known for some time that prions play a large role in molecular biology, but the transformation and replication process into rouge prions has been at the forefront of research, so this study is interesting. (metafilter.com)
  • 810 words - 4 pages Viruses, bacteria, and prions are all major topics in biology. (brightkite.com)
  • To look at interaction between Aβ and prions, first author Rodrigo Morales dosed young (45-day-old) or old (365-day-old) Tg2576 mice with infectious prions by intraperitoneal injection, and compared their progress to uninoculated transgenics or inoculated wild-type mice. (alzforum.org)
  • The finding that prion null mice do not have a significant overt phenotype suggests that the normal function of PrP is of minor importance. (nih.gov)
  • When you transmit prions from sheep to mice, they become more virulent over time. (scripps.edu)
  • Importantly, their data, which appeared in the August 6 Journal of Neuroscience, show that a pool of prions exists in the neuronal cytosol, supporting a recent hypothesis that minute amounts of misfolded, cytosolic prion may be sufficient to cripple neurons. (alzforum.org)
  • 15B3 specifically precipitates bovine, murine or human rogue, but not normal conformer, suggesting that it recognizes an epitope common to rogue prions from different species. (mad-cow.org)
  • This apparent lack of zoonotic transmission by scrapie is considered to be a consequence of the transmission barrier phenomenon that naturally limits the propagation of prions from one species to another 5 . (nature.com)
  • This is a list of the genera, species, and subspecies belonging to the prions, which belong to the Procellariiformes. (wikipedia.org)
  • Prion replication is subject to epimutation and natural selection just as for other forms of replication, and their structure varies slightly between species. (wikipedia.org)
  • With this technique it is possible to assess within a few days whether prions are efficiently transmissible between different animal species. (wur.nl)
  • The occurrence of vCJD has provided significant evidence to show that the transmission barrier does not constitute an absolute protection against the zoonotic risk of prions that circulate in animal populations. (nature.com)
  • Keeping cervids out of grazing or growing fields should be considered as a way to manage the risk of prions entering the human food chain. (virology.ws)
  • Scientists who deal with prions] are not going to speak out, especially with the political repercussions in science. (rense.com)
  • The scientists next tested whether the technique could be used to detect prions in blood samples from 14 people with vCJD and 153 controls. (nih.gov)
  • In the new study, the scientists used the Scrapie Cell Assay, a test originally created by Weissmann that is highly sensitive to minute quantities of prions. (thaindian.com)
  • The prion theory was controversial at first, since other known infectious agents - bacteria, viruses, parasites and fungi - contain their own genetic information (DNA or RNA). (sourcewatch.org)
  • Prions are so small that they are even smaller than viruses and can only be seen through an electron microscope when they have aggregated and formed a cluster. (news-medical.net)
  • Prions, bacteria, and viruses are all kind of blurred together and known generically as the same thing. (brightkite.com)
  • The three that I will be discussing are bacteria, viruses, and prions. (brightkite.com)
  • Bacteria and viruses are more similar with each other than a prion with either one. (brightkite.com)
  • Are Viruses, Prions And Viriods Alive? (brightkite.com)
  • 1023 words - 5 pages Prions, bacteria, and viruses are all kind of blurred together and known generically as the same thing. (brightkite.com)
  • 1323 words - 5 pages Many people get viruses, prions, and bacteria confused in multiple ways. (brightkite.com)
  • Prions are very different from infectious organisms like bacteria and viruses. (sixwise.com)
  • On the face of it, you have exactly the same process of mutation and adaptive change in prions as you see in viruses," said Charles Weissmann, the head of Scripps Florida's Department of Infectology, who led the study. (scripps.edu)
  • Prions are proteinaceous infectious agents that lack nucleic acids ( 1 , 2 ). (pnas.org)