A genus of potentially oncogenic viruses of the family POLYOMAVIRIDAE. These viruses are normally present in their natural hosts as latent infections. The virus is oncogenic in hosts different from the species of origin.
Infections with POLYOMAVIRUS, which are often cultured from the urine of kidney transplant patients. Excretion of BK VIRUS is associated with ureteral strictures and CYSTITIS, and that of JC VIRUS with progressive multifocal leukoencephalopathy (LEUKOENCEPHALOPATHY, PROGRESSIVE MULTIFOCAL).
Polyomavirus antigens which cause infection and cellular transformation. The large T antigen is necessary for the initiation of viral DNA synthesis, repression of transcription of the early region and is responsible in conjunction with the middle T antigen for the transformation of primary cells. Small T antigen is necessary for the completion of the productive infection cycle.
A species of POLYOMAVIRUS suspected to be the cause of most cases of MERKEL CELL CARCINOMA, a rare but highly lethal form of skin cancer.
Substances that are recognized by the immune system and induce an immune reaction.
A species of POLYOMAVIRUS apparently infecting over 90% of children but not clearly associated with any clinical illness in childhood. The virus remains latent in the body throughout life and can be reactivated under certain circumstances.
Those proteins recognized by antibodies from serum of animals bearing tumors induced by viruses; these proteins are presumably coded for by the nucleic acids of the same viruses that caused the neoplastic transformation.
A species of POLYOMAVIRUS, originally isolated from the brain of a patient with progressive multifocal leukoencephalopathy. The patient's initials J.C. gave the virus its name. Infection is not accompanied by any apparent illness but serious demyelinating disease can appear later, probably following reactivation of latent virus.
A carcinoma arising from MERKEL CELLS located in the basal layer of the epidermis and occurring most commonly as a primary neuroendocrine carcinoma of the skin. Merkel cells are tactile cells of neuroectodermal origin and histologically show neurosecretory granules. The skin of the head and neck are a common site of Merkel cell carcinoma, occurring generally in elderly patients. (Holland et al., Cancer Medicine, 3d ed, p1245)
Substances elaborated by bacteria that have antigenic activity.
Infections produced by oncogenic viruses. The infections caused by DNA viruses are less numerous but more diverse than those caused by the RNA oncogenic viruses.
Proteins, glycoprotein, or lipoprotein moieties on surfaces of tumor cells that are usually identified by monoclonal antibodies. Many of these are of either embryonic or viral origin.
Antigens on surfaces of cells, including infectious or foreign cells or viruses. They are usually protein-containing groups on cell membranes or walls and may be isolated.
Substances elaborated by viruses that have antigenic activity.
Deoxyribonucleic acid that makes up the genetic material of viruses.
Modified epidermal cells located in the stratum basale. They are found mostly in areas where sensory perception is acute, such as the fingertips. Merkel cells are closely associated with an expanded terminal bulb of an afferent myelinated nerve fiber. Do not confuse with Merkel's corpuscle which is a combination of a neuron and an epidermal cell.
Proteins that form the CAPSID of VIRUSES.
A species of POLYOMAVIRUS originally isolated from Rhesus monkey kidney tissue. It produces malignancy in human and newborn hamster kidney cell cultures.
Any part or derivative of any protozoan that elicits immunity; malaria (Plasmodium) and trypanosome antigens are presently the most frequently encountered.
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.
An opportunistic viral infection of the central nervous system associated with conditions that impair cell-mediated immunity (e.g., ACQUIRED IMMUNODEFICIENCY SYNDROME and other IMMUNOLOGIC DEFICIENCY SYNDROMES; HEMATOLOGIC NEOPLASMS; IMMUNOSUPPRESSION; and COLLAGEN DISEASES). The causative organism is JC Polyomavirus (JC VIRUS) which primarily affects oligodendrocytes, resulting in multiple areas of demyelination. Clinical manifestations include DEMENTIA; ATAXIA; visual disturbances; and other focal neurologic deficits, generally progressing to a vegetative state within 6 months. (From Joynt, Clinical Neurology, 1996, Ch26, pp36-7)
Antigens determined by leukocyte loci found on chromosome 6, the major histocompatibility loci in humans. They are polypeptides or glycoproteins found on most nucleated cells and platelets, determine tissue types for transplantation, and are associated with certain diseases.
Established cell cultures that have the potential to propagate indefinitely.
Substances of fungal origin that have antigenic activity.
The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.
Differentiation antigens residing on mammalian leukocytes. CD stands for cluster of differentiation, which refers to groups of monoclonal antibodies that show similar reactivity with certain subpopulations of antigens of a particular lineage or differentiation stage. The subpopulations of antigens are also known by the same CD designation.
Any part or derivative of a helminth that elicits an immune reaction. The most commonly seen helminth antigens are those of the schistosomes.
The major group of transplantation antigens in the mouse.
A family of small, non-enveloped DNA viruses, infecting mainly MAMMALS, and containing a single genus: POLYOMAVIRUS.
An inheritable change in cells manifested by changes in cell division and growth and alterations in cell surface properties. It is induced by infection with a transforming virus.
The process by which a DNA molecule is duplicated.
A glycoprotein that is secreted into the luminal surface of the epithelia in the gastrointestinal tract. It is found in the feces and pancreaticobiliary secretions and is used to monitor the response to colon cancer treatment.
The process of intracellular viral multiplication, consisting of the synthesis of PROTEINS; NUCLEIC ACIDS; and sometimes LIPIDS, and their assembly into a new infectious particle.
Antibodies produced by a single clone of cells.
A subclass of HLA-D antigens that consist of alpha and beta chains. The inheritance of HLA-DR antigens differs from that of the HLA-DQ ANTIGENS and HLA-DP ANTIGENS.
Molecules on the surface of T-lymphocytes that recognize and combine with antigens. The receptors are non-covalently associated with a complex of several polypeptides collectively called CD3 antigens (ANTIGENS, CD3). Recognition of foreign antigen and the major histocompatibility complex is accomplished by a single heterodimeric antigen-receptor structure, composed of either alpha-beta (RECEPTORS, ANTIGEN, T-CELL, ALPHA-BETA) or gamma-delta (RECEPTORS, ANTIGEN, T-CELL, GAMMA-DELTA) chains.
The outer protein protective shell of a virus, which protects the viral nucleic acid.
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.
A group of antigens that includes both the major and minor histocompatibility antigens. The former are genetically determined by the major histocompatibility complex. They determine tissue type for transplantation and cause allograft rejections. The latter are systems of allelic alloantigens that can cause weak transplant rejection.
Sites on an antigen that interact with specific antibodies.
Nuclear antigen with a role in DNA synthesis, DNA repair, and cell cycle progression. PCNA is required for the coordinated synthesis of both leading and lagging strands at the replication fork during DNA replication. PCNA expression correlates with the proliferation activity of several malignant and non-malignant cell types.
Serological reactions in which an antiserum against one antigen reacts with a non-identical but closely related antigen.
The functional hereditary units of VIRUSES.
Large, transmembrane, non-covalently linked glycoproteins (alpha and beta). Both chains can be polymorphic although there is more structural variation in the beta chains. The class II antigens in humans are called HLA-D ANTIGENS and are coded by a gene on chromosome 6. In mice, two genes named IA and IE on chromosome 17 code for the H-2 antigens. The antigens are found on B-lymphocytes, macrophages, epidermal cells, and sperm and are thought to mediate the competence of and cellular cooperation in the immune response. The term IA antigens used to refer only to the proteins encoded by the IA genes in the mouse, but is now used as a generic term for any class II histocompatibility antigen.
A glycoprotein that is a kallikrein-like serine proteinase and an esterase, produced by epithelial cells of both normal and malignant prostate tissue. It is an important marker for the diagnosis of prostate cancer.
The lipopolysaccharide-protein somatic antigens, usually from gram-negative bacteria, important in the serological classification of enteric bacilli. The O-specific chains determine the specificity of the O antigens of a given serotype. O antigens are the immunodominant part of the lipopolysaccharide molecule in the intact bacterial cell. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)
IMMUNOGLOBULINS on the surface of B-LYMPHOCYTES. Their MESSENGER RNA contains an EXON with a membrane spanning sequence, producing immunoglobulins in the form of type I transmembrane proteins as opposed to secreted immunoglobulins (ANTIBODIES) which do not contain the membrane spanning segment.
Immunoglobulins produced in response to VIRAL ANTIGENS.
Lymphocytes responsible for cell-mediated immunity. Two types have been identified - cytotoxic (T-LYMPHOCYTES, CYTOTOXIC) and helper T-lymphocytes (T-LYMPHOCYTES, HELPER-INDUCER). They are formed when lymphocytes circulate through the THYMUS GLAND and differentiate to thymocytes. When exposed to an antigen, they divide rapidly and produce large numbers of new T cells sensitized to that antigen.
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.
In vitro method for producing large amounts of specific DNA or RNA fragments of defined length and sequence from small amounts of short oligonucleotide flanking sequences (primers). The essential steps include thermal denaturation of the double-stranded target molecules, annealing of the primers to their complementary sequences, and extension of the annealed primers by enzymatic synthesis with DNA polymerase. The reaction is efficient, specific, and extremely sensitive. Uses for the reaction include disease diagnosis, detection of difficult-to-isolate pathogens, mutation analysis, genetic testing, DNA sequencing, and analyzing evolutionary relationships.
Cis-acting DNA sequences which can increase transcription of genes. Enhancers can usually function in either orientation and at various distances from a promoter.
Liquid by-product of excretion produced in the kidneys, temporarily stored in the bladder until discharge through the URETHRA.
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.
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 trisaccharide antigen expressed on glycolipids and many cell-surface glycoproteins. In the blood the antigen is found on the surface of NEUTROPHILS; EOSINOPHILS; and MONOCYTES. In addition, CD15 antigen is a stage-specific embryonic antigen.
The major immunoglobulin isotype class in normal human serum. There are several isotype subclasses of IgG, for example, IgG1, IgG2A, and IgG2B.
Carbohydrate antigens expressed by malignant tissue. They are useful as tumor markers and are measured in the serum by means of a radioimmunoassay employing monoclonal antibodies.
Products of viral oncogenes, most commonly retroviral oncogenes. They usually have transforming and often protein kinase activities.
Membrane-associated tyrosine-specific kinases encoded by the c-src genes. They have an important role in cellular growth control. Truncation of carboxy-terminal residues in pp60(c-src) leads to PP60(V-SRC) which has the ability to transform cells. This kinase pp60 c-src should not be confused with csk, also known as c-src kinase.
A specific HLA-A surface antigen subtype. Members of this subtype contain alpha chains that are encoded by the HLA-A*02 allele family.
Differentiation antigens found on thymocytes and on cytotoxic and suppressor T-lymphocytes. CD8 antigens are members of the immunoglobulin supergene family and are associative recognition elements in MHC (Major Histocompatibility Complex) Class I-restricted interactions.
Cell lines whose original growing procedure consisted being transferred (T) every 3 days and plated at 300,000 cells per plate (J Cell Biol 17:299-313, 1963). Lines have been developed using several different strains of mice. Tissues are usually fibroblasts derived from mouse embryos but other types and sources have been developed as well. The 3T3 lines are valuable in vitro host systems for oncogenic virus transformation studies, since 3T3 cells possess a high sensitivity to CONTACT INHIBITION.
Proteins found in any species of virus.
The complete genetic complement contained in a DNA or RNA molecule in a virus.
The uptake of naked or purified DNA by CELLS, usually meaning the process as it occurs in eukaryotic cells. It is analogous to bacterial transformation (TRANSFORMATION, BACTERIAL) and both are routinely employed in GENE TRANSFER TECHNIQUES.
Sets of cell surface antigens located on BLOOD CELLS. They are usually membrane GLYCOPROTEINS or GLYCOLIPIDS that are antigenically distinguished by their carbohydrate moieties.
Those hepatitis B antigens found on the surface of the Dane particle and on the 20 nm spherical and tubular particles. Several subspecificities of the surface antigen are known. These were formerly called the Australia antigen.
Complex of at least five membrane-bound polypeptides in mature T-lymphocytes that are non-covalently associated with one another and with the T-cell receptor (RECEPTORS, ANTIGEN, T-CELL). The CD3 complex includes the gamma, delta, epsilon, zeta, and eta chains (subunits). When antigen binds to the T-cell receptor, the CD3 complex transduces the activating signals to the cytoplasm of the T-cell. The CD3 gamma and delta chains (subunits) are separate from and not related to the gamma/delta chains of the T-cell receptor (RECEPTORS, ANTIGEN, T-CELL, GAMMA-DELTA).
Test for tissue antigen using either a direct method, by conjugation of antibody with fluorescent dye (FLUORESCENT ANTIBODY TECHNIQUE, DIRECT) or an indirect method, by formation of antigen-antibody complex which is then labeled with fluorescein-conjugated anti-immunoglobulin antibody (FLUORESCENT ANTIBODY TECHNIQUE, INDIRECT). The tissue is then examined by fluorescence microscopy.
A broad category of viral proteins that play indirect roles in the biological processes and activities of viruses. Included here are proteins that either regulate the expression of viral genes or are involved in modifying host cell functions. Many of the proteins in this category serve multiple functions.
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.
Polymorphic class I human histocompatibility (HLA) surface antigens present on almost all nucleated cells. At least 20 antigens have been identified which are encoded by the A locus of multiple alleles on chromosome 6. They serve as targets for T-cell cytolytic responses and are involved with acceptance or rejection of tissue/organ grafts.
Membrane glycoproteins consisting of an alpha subunit and a BETA 2-MICROGLOBULIN beta subunit. In humans, highly polymorphic genes on CHROMOSOME 6 encode the alpha subunits of class I antigens and play an important role in determining the serological specificity of the surface antigen. Class I antigens are found on most nucleated cells and are generally detected by their reactivity with alloantisera. These antigens are recognized during GRAFT REJECTION and restrict cell-mediated lysis of virus-infected cells.
Any of the processes by which cytoplasmic factors influence the differential control of gene action in viruses.
The transference of a kidney from one human or animal to another.
Morphologic alteration of small B LYMPHOCYTES or T LYMPHOCYTES in culture into large blast-like cells able to synthesize DNA and RNA and to divide mitotically. It is induced by INTERLEUKINS; MITOGENS such as PHYTOHEMAGGLUTININS, and by specific ANTIGENS. It may also occur in vivo as in GRAFT REJECTION.
The biosynthesis of RNA carried out on a template of DNA. The biosynthesis of DNA from an RNA template is called REVERSE TRANSCRIPTION.
Human immune-response or Class II antigens found mainly, but not exclusively, on B-lymphocytes and produced from genes of the HLA-D locus. They are extremely polymorphic families of glycopeptides, each consisting of two chains, alpha and beta. This group of antigens includes the -DR, -DQ and -DP designations, of which HLA-DR is most studied; some of these glycoproteins are associated with certain diseases, possibly of immune etiology.
The property of antibodies which enables them to react with some ANTIGENIC DETERMINANTS and not with others. Specificity is dependent on chemical composition, physical forces, and molecular structure at the binding site.
Molecules on the surface of B- and T-lymphocytes that recognize and combine with specific antigens.
High-molecular weight glycoproteins uniquely expressed on the surface of LEUKOCYTES and their hemopoietic progenitors. They contain a cytoplasmic protein tyrosine phosphatase activity which plays a role in intracellular signaling from the CELL SURFACE RECEPTORS. The CD45 antigens occur as multiple isoforms that result from alternative mRNA splicing and differential usage of three exons.
Antigens of the virion of the HEPATITIS B VIRUS or the Dane particle, its surface (HEPATITIS B SURFACE ANTIGENS), core (HEPATITIS B CORE ANTIGENS), and other associated antigens, including the HEPATITIS B E ANTIGENS.
The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.
55-kDa antigens found on HELPER-INDUCER T-LYMPHOCYTES and on a variety of other immune cell types. CD4 antigens are members of the immunoglobulin supergene family and are implicated as associative recognition elements in MAJOR HISTOCOMPATIBILITY COMPLEX class II-restricted immune responses. On T-lymphocytes they define the helper/inducer subset. CD4 antigens also serve as INTERLEUKIN-15 receptors and bind to the HIV receptors, binding directly to the HIV ENVELOPE PROTEIN GP120.
Viral proteins that are components of the mature assembled VIRUS PARTICLES. They may include nucleocapsid core proteins (gag proteins), enzymes packaged within the virus particle (pol proteins), and membrane components (env proteins). These do not include the proteins encoded in the VIRAL GENOME that are produced in infected cells but which are not packaged in the mature virus particle,i.e. the so called non-structural proteins (VIRAL NONSTRUCTURAL PROTEINS).
The sum of the weight of all the atoms in a molecule.
Cell changes manifested by escape from control mechanisms, increased growth potential, alterations in the cell surface, karyotypic abnormalities, morphological and biochemical deviations from the norm, and other attributes conferring the ability to invade, metastasize, and kill.
The processes triggered by interactions of ANTIBODIES with their ANTIGENS.
Glycoproteins expressed on cortical thymocytes and on some dendritic cells and B-cells. Their structure is similar to that of MHC Class I and their function has been postulated as similar also. CD1 antigens are highly specific markers for human LANGERHANS CELLS.
Proteins prepared by recombinant DNA technology.
Immunoglobulins produced in a response to BACTERIAL ANTIGENS.
Serum that contains antibodies. It is obtained from an animal that has been immunized either by ANTIGEN injection or infection with microorganisms containing the antigen.
The production of ANTIBODIES by proliferating and differentiated B-LYMPHOCYTES under stimulation by ANTIGENS.
BIRDS of the large family Psittacidae, widely distributed in tropical regions and having a distinctive stout, curved hooked bill. The family includes LOVEBIRDS; AMAZON PARROTS; conures; PARAKEETS; and many other kinds of parrots.
The parts of a macromolecule that directly participate in its specific combination with another molecule.
Class I human histocompatibility (HLA) surface antigens encoded by more than 30 detectable alleles on locus B of the HLA complex, the most polymorphic of all the HLA specificities. Several of these antigens (e.g., HLA-B27, -B7, -B8) are strongly associated with predisposition to rheumatoid and other autoimmune disorders. Like other class I HLA determinants, they are involved in the cellular immune reactivity of cytolytic T lymphocytes.
Proteins which bind to DNA. The family includes proteins which bind to both double- and single-stranded DNA and also includes specific DNA binding proteins in serum which can be used as markers for malignant diseases.
Antigens expressed primarily on the membranes of living cells during sequential stages of maturation and differentiation. As immunologic markers they have high organ and tissue specificity and are useful as probes in studies of normal cell development as well as neoplastic transformation.
Deliberate stimulation of the host's immune response. ACTIVE IMMUNIZATION involves administration of ANTIGENS or IMMUNOLOGIC ADJUVANTS. PASSIVE IMMUNIZATION involves administration of IMMUNE SERA or LYMPHOCYTES or their extracts (e.g., transfer factor, immune RNA) or transplantation of immunocompetent cell producing tissue (thymus or bone marrow).
DNA molecules capable of autonomous replication within a host cell and into which other DNA sequences can be inserted and thus amplified. Many are derived from PLASMIDS; BACTERIOPHAGES; or VIRUSES. They are used for transporting foreign genes into recipient cells. Genetic vectors possess a functional replicator site and contain GENETIC MARKERS to facilitate their selective recognition.
Lymphoid cells concerned with humoral immunity. They are short-lived cells resembling bursa-derived lymphocytes of birds in their production of immunoglobulin upon appropriate stimulation.
A melanosome-specific protein that plays a role in the expression, stability, trafficking, and processing of GP100 MELANOMA ANTIGEN, which is critical to the formation of Stage II MELANOSOMES. The protein is used as an antigen marker for MELANOMA cells.
Semi-synthetic complex derived from nucleic-acid free viral particles. They are essentially reconstituted viral coats, where the infectious nucleocapsid is replaced by a compound of choice. Virosomes retain their fusogenic activity and thus deliver the incorporated compound (antigens, drugs, genes) inside the target cell. They can be used for vaccines (VACCINES, VIROSOME), drug delivery, or gene transfer.
Body organ that filters blood for the secretion of URINE and that regulates ion concentrations.
An encapsulated lymphatic organ through which venous blood filters.
Tumors or cancer of the SKIN.
DNA sequences which are recognized (directly or indirectly) and bound by a DNA-dependent RNA polymerase during the initiation of transcription. Highly conserved sequences within the promoter include the Pribnow box in bacteria and the TATA BOX in eukaryotes.
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.
Antigens associated with specific proteins of the human adult T-cell immunodeficiency virus (HIV); also called HTLV-III-associated and lymphadenopathy-associated virus (LAV) antigens.
The expelling of virus particles from the body. Important routes include the respiratory tract, genital tract, and intestinal tract. Virus shedding is an important means of vertical transmission (INFECTIOUS DISEASE TRANSMISSION, VERTICAL).
A costimulatory ligand expressed by ANTIGEN-PRESENTING CELLS that binds to CTLA-4 ANTIGEN with high specificity and to CD28 ANTIGEN with low specificity. The interaction of CD80 with CD28 ANTIGEN provides a costimulatory signal to T-LYMPHOCYTES, while its interaction with CTLA-4 ANTIGEN may play a role in inducing PERIPHERAL TOLERANCE.
Specific molecular components of the cell capable of recognizing and interacting with a virus, and which, after binding it, are capable of generating some signal that initiates the chain of events leading to the biological response.
Cells grown in vitro from neoplastic tissue. If they can be established as a TUMOR CELL LINE, they can be propagated in cell culture indefinitely.
The species Oryctolagus cuniculus, in the family Leporidae, order LAGOMORPHA. Rabbits are born in burrows, furless, and with eyes and ears closed. In contrast with HARES, rabbits have 22 chromosome pairs.
A human or animal whose immunologic mechanism is deficient because of an immunodeficiency disorder or other disease or as the result of the administration of immunosuppressive drugs or radiation.
Eukaryotic cell line obtained in a quiescent or stationary phase which undergoes conversion to a state of unregulated growth in culture, resembling an in vitro tumor. It occurs spontaneously or through interaction with viruses, oncogenes, radiation, or drugs/chemicals.
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.
Nuclear antigens encoded by VIRAL GENES found in HUMAN HERPESVIRUS 4. At least six nuclear antigens have been identified.
Immunologic techniques based on the use of: (1) enzyme-antibody conjugates; (2) enzyme-antigen conjugates; (3) antienzyme antibody followed by its homologous enzyme; or (4) enzyme-antienzyme complexes. These are used histologically for visualizing or labeling tissue specimens.
Differentiation antigens expressed on B-lymphocytes and B-cell precursors. They are involved in regulation of B-cell proliferation.
A family of DNA binding proteins that regulate expression of a variety of GENES during CELL DIFFERENTIATION and APOPTOSIS. Family members contain a highly conserved carboxy-terminal basic HELIX-TURN-HELIX MOTIF involved in dimerization and sequence-specific DNA binding.
Histochemical localization of immunoreactive substances using labeled antibodies as reagents.
RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.
The infective system of a virus, composed of the viral genome, a protein core, and a protein coat called a capsid, which may be naked or enclosed in a lipoprotein envelope called the peplos.
Connective tissue cells which secrete an extracellular matrix rich in collagen and other macromolecules.
Ribonucleic acid that makes up the genetic material of viruses.
Endogenous substances, usually proteins, which are effective in the initiation, stimulation, or termination of the genetic transcription process.
The relationships of groups of organisms as reflected by their genetic makeup.
An order of BIRDS comprised of several families and more than 300 species. It includes COCKATOOS; PARROTS; PARAKEETS; macaws; and BUDGERIGARS.
Antigens stimulating the formation of, or combining with heterophile antibodies. They are cross-reacting antigens found in phylogenetically unrelated species.
A phosphoprotein phosphatase subtype that is comprised of a catalytic subunit and two different regulatory subunits. At least two genes encode isoforms of the protein phosphatase catalytic subunit, while several isoforms of regulatory subunits exist due to the presence of multiple genes and the alternative splicing of their mRNAs. Protein phosphatase 2 acts on a broad variety of cellular proteins and may play a role as a regulator of intracellular signaling processes.
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 hepatitis B antigen within the core of the Dane particle, the infectious hepatitis virion.
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.
The major interferon produced by mitogenically or antigenically stimulated LYMPHOCYTES. It is structurally different from TYPE I INTERFERON and its major activity is immunoregulation. It has been implicated in the expression of CLASS II HISTOCOMPATIBILITY ANTIGENS in cells that do not normally produce them, leading to AUTOIMMUNE DISEASES.
A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).
A member of the tumor necrosis factor receptor superfamily with specificity for CD40 LIGAND. It is found on mature B-LYMPHOCYTES and some EPITHELIAL CELLS, lymphoid DENDRITIC CELLS. Evidence suggests that CD40-dependent activation of B-cells is important for generation of memory B-cells within the germinal centers. Mutations of the gene for CD40 antigen result in HYPER-IGM IMMUNODEFICIENCY SYNDROME, TYPE 3. Signaling of the receptor occurs through its association with TNF RECEPTOR-ASSOCIATED FACTORS.
Serologic tests in which a positive reaction manifested by visible CHEMICAL PRECIPITATION occurs when a soluble ANTIGEN reacts with its precipitins, i.e., ANTIBODIES that can form a precipitate.
Technique involving the diffusion of antigen or antibody through a semisolid medium, usually agar or agarose gel, with the result being a precipitin reaction.
Endogenous tissue constituents that have the ability to interact with AUTOANTIBODIES and cause an immune response.
Within a eukaryotic cell, a membrane-limited body which contains chromosomes and one or more nucleoli (CELL NUCLEOLUS). The nuclear membrane consists of a double unit-type membrane which is perforated by a number of pores; the outermost membrane is continuous with the ENDOPLASMIC RETICULUM. A cell may contain more than one nucleus. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)
Immunoglobulin molecules having a specific amino acid sequence by virtue of which they interact only with the ANTIGEN (or a very similar shape) that induced their synthesis in cells of the lymphoid series (especially PLASMA CELLS).
The assembly of VIRAL STRUCTURAL PROTEINS and nucleic acid (VIRAL DNA or VIRAL RNA) to form a VIRUS PARTICLE.
Nucleic acid sequences involved in regulating the expression of genes.
An enzyme that catalyzes the conversion of phosphatidylinositol (PHOSPHATIDYLINOSITOLS) to phosphatidylinositol 4-phosphate, the first committed step in the biosynthesis of phosphatidylinositol 4,5-bisphosphate.
Biologically active DNA which has been formed by the in vitro joining of segments of DNA from different sources. It includes the recombination joint or edge of a heteroduplex region where two recombining DNA molecules are connected.
A class of immunoglobulin bearing mu chains (IMMUNOGLOBULIN MU-CHAINS). IgM can fix COMPLEMENT. The name comes from its high molecular weight and originally being called a macroglobulin.
A critical subpopulation of regulatory T-lymphocytes involved in MHC Class I-restricted interactions. They include both cytotoxic T-lymphocytes (T-LYMPHOCYTES, CYTOTOXIC) and CD8+ suppressor T-lymphocytes.
A group of differentiation surface antigens, among the first to be discovered on thymocytes and T-lymphocytes. Originally identified in the mouse, they are also found in other species including humans, and are expressed on brain neurons and other cells.
Laboratory mice that have been produced from a genetically manipulated EGG or EMBRYO, MAMMALIAN.
A multistage process that includes cloning, physical mapping, subcloning, determination of the DNA SEQUENCE, and information analysis.
A glycolipid, cross-species antigen that induces production of antisheep hemolysin. It is present on the tissue cells of many species but absent in humans. It is found in many infectious agents.
The complex formed by the binding of antigen and antibody molecules. The deposition of large antigen-antibody complexes leading to tissue damage causes IMMUNE COMPLEX DISEASES.
Production of new arrangements of DNA by various mechanisms such as assortment and segregation, CROSSING OVER; GENE CONVERSION; GENETIC TRANSFORMATION; GENETIC CONJUGATION; GENETIC TRANSDUCTION; or mixed infection of viruses.
Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.
Use of restriction endonucleases to analyze and generate a physical map of genomes, genes, or other segments of DNA.
An N-acyl derivative of neuraminic acid. N-acetylneuraminic acid occurs in many polysaccharides, glycoproteins, and glycolipids in animals and bacteria. (From Dorland, 28th ed, p1518)
Product of the retinoblastoma tumor suppressor gene. It is a nuclear phosphoprotein hypothesized to normally act as an inhibitor of cell proliferation. Rb protein is absent in retinoblastoma cell lines. It also has been shown to form complexes with the adenovirus E1A protein, the SV40 T antigen, and the human papilloma virus E7 protein.
Genes which regulate or circumscribe the activity of other genes; specifically, genes which code for PROTEINS or RNAs which have GENE EXPRESSION REGULATION functions.
A sex-specific cell surface antigen produced by the sex-determining gene of the Y chromosome in mammals. It causes syngeneic grafts from males to females to be rejected and interacts with somatic elements of the embryologic undifferentiated gonad to produce testicular organogenesis.
A genus of owlet moths of the family Noctuidae. These insects are used in molecular biology studies during all stages of their life cycle.
A heterogeneous group of immunocompetent cells that mediate the cellular immune response by processing and presenting antigens to the T-cells. Traditional antigen-presenting cells include MACROPHAGES; DENDRITIC CELLS; LANGERHANS CELLS; and B-LYMPHOCYTES. FOLLICULAR DENDRITIC CELLS are not traditional antigen-presenting cells, but because they hold antigen on their cell surface in the form of IMMUNE COMPLEXES for B-cell recognition they are considered so by some authors.
Pathological processes of the KIDNEY or its component tissues.
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.
Elements of limited time intervals, contributing to particular results or situations.
Family of INSECT VIRUSES containing two subfamilies: Eubaculovirinae (occluded baculoviruses) and Nudibaculovirinae (nonoccluded baculoviruses). The Eubaculovirinae, which contain polyhedron-shaped inclusion bodies, have two genera: NUCLEOPOLYHEDROVIRUS and GRANULOVIRUS. Baculovirus vectors are used for expression of foreign genes in insects.
EPIDEMIOLOGIC STUDIES based on the detection through serological testing of characteristic change in the serum level of specific ANTIBODIES. Latent subclinical infections and carrier states can thus be detected in addition to clinically overt cases.
Specialized cells of the hematopoietic system that have branch-like extensions. They are found throughout the lymphatic system, and in non-lymphoid tissues such as SKIN and the epithelia of the intestinal, respiratory, and reproductive tracts. They trap and process ANTIGENS, and present them to T-CELLS, thereby stimulating CELL-MEDIATED IMMUNITY. They are different from the non-hematopoietic FOLLICULAR DENDRITIC CELLS, which have a similar morphology and immune system function, but with respect to humoral immunity (ANTIBODY PRODUCTION).
A species of baboon in the family CERCOPITHECIDAE found in southern Africa. They are dark colored and have a variable social structure.
Sequences of DNA or RNA that occur in multiple copies. There are several types: INTERSPERSED REPETITIVE SEQUENCES are copies of transposable elements (DNA TRANSPOSABLE ELEMENTS or RETROELEMENTS) dispersed throughout the genome. TERMINAL REPEAT SEQUENCES flank both ends of another sequence, for example, the long terminal repeats (LTRs) on RETROVIRUSES. Variations may be direct repeats, those occurring in the same direction, or inverted repeats, those opposite to each other in direction. TANDEM REPEAT SEQUENCES are copies which lie adjacent to each other, direct or inverted (INVERTED REPEAT SEQUENCES).
Serologic tests based on inactivation of complement by the antigen-antibody complex (stage 1). Binding of free complement can be visualized by addition of a second antigen-antibody system such as red cells and appropriate red cell antibody (hemolysin) requiring complement for its completion (stage 2). Failure of the red cells to lyse indicates that a specific antigen-antibody reaction has taken place in stage 1. If red cells lyse, free complement is present indicating no antigen-antibody reaction occurred in stage 1.
A group of the D-related HLA antigens found to differ from the DR antigens in genetic locus and therefore inheritance. These antigens are polymorphic glycoproteins comprising alpha and beta chains and are found on lymphoid and other cells, often associated with certain diseases.
Technique using an instrument system for making, processing, and displaying one or more measurements on individual cells obtained from a cell suspension. Cells are usually stained with one or more fluorescent dyes specific to cell components of interest, e.g., DNA, and fluorescence of each cell is measured as it rapidly transverses the excitation beam (laser or mercury arc lamp). Fluorescence provides a quantitative measure of various biochemical and biophysical properties of the cell, as well as a basis for cell sorting. Other measurable optical parameters include light absorption and light scattering, the latter being applicable to the measurement of cell size, shape, density, granularity, and stain uptake.
An albumin obtained from the white of eggs. It is a member of the serpin superfamily.
A costimulatory ligand expressed by ANTIGEN-PRESENTING CELLS that binds to CD28 ANTIGEN with high specificity and to CTLA-4 ANTIGEN with low specificity. The interaction of CD86 with CD28 ANTIGEN provides a stimulatory signal to T-LYMPHOCYTES, while its interaction with CTLA-4 ANTIGEN may play a role in inducing PERIPHERAL TOLERANCE.
A unique DNA sequence of a replicon at which DNA REPLICATION is initiated and proceeds bidirectionally or unidirectionally. It contains the sites where the first separation of the complementary strands occurs, a primer RNA is synthesized, and the switch from primer RNA to DNA synthesis takes place. (Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed)
Y-box-binding protein 1 was originally identified as a DNA-binding protein that interacts with Y-box PROMOTER REGIONS of MHC CLASS II GENES. It is a highly conserved transcription factor that regulates expression of a wide variety of GENES.
Immunized T-lymphocytes which can directly destroy appropriate target cells. These cytotoxic lymphocytes may be generated in vitro in mixed lymphocyte cultures (MLC), in vivo during a graft-versus-host (GVH) reaction, or after immunization with an allograft, tumor cell or virally transformed or chemically modified target cell. The lytic phenomenon is sometimes referred to as cell-mediated lympholysis (CML). These CD8-positive cells are distinct from NATURAL KILLER CELLS and NATURAL KILLER T-CELLS. There are two effector phenotypes: TC1 and TC2.
Large crested BIRDS in the family Cacatuidae, found in Australia, New Guinea, and islands adjacent to the Philippines. The cockatiel (species Nymphicus hollandicus) is much smaller.
A group of genetically identical cells all descended from a single common ancestral cell by mitosis in eukaryotes or by binary fission in prokaryotes. Clone cells also include populations of recombinant DNA molecules all carrying the same inserted sequence. (From King & Stansfield, Dictionary of Genetics, 4th ed)
The fission of a CELL. It includes CYTOKINESIS, when the CYTOPLASM of a cell is divided, and CELL NUCLEUS DIVISION.

Human topoisomerase I promotes initiation of simian virus 40 DNA replication in vitro. (1/1802)

Addition of purified human topoisomerase I (topo I) to simian virus 40 T antigen-driven in vitro DNA replication reactions performed with topo I-deficient extracts results in a greater than 10-fold stimulation of completed molecules as well as a more than 3-fold enhancement of overall DNA replication. To further characterize this stimulation, we first demonstrate that bovine topo I but not Escherichia coli topo I can also enhance DNA replication. By using several human topo I mutants, we show that a catalytically active form of topo I is required. To delineate whether topo I influences the initiation or the elongation step of replication, we performed delayed pulse, pulse-chase, and delayed pulse-chase experiments. The results illustrate that topo I cannot promote the completion of partially replicated molecules but is needed from the beginning of the reaction to initiate replication. Competitive inhibition experiments with the topo I binding T antigen fragment 1-246T and a catalytically inactive topo I mutant suggest that part of topo I's stimulation of replication is mediated through a direct interaction with T antigen. Collectively, our data indicate that topo I enhances the synthesis of fully replicated DNA molecules by forming essential interactions with T antigen and stimulating initiation.  (+info)

Telomerase activity is sufficient to allow transformed cells to escape from crisis. (2/1802)

The introduction of simian virus 40 large T antigen (SVLT) into human primary cells enables them to proliferate beyond their normal replicative life span. In most cases, this temporary escape from senescence eventually ends in a second proliferative block known as "crisis," during which the cells cease growing or die. Rare immortalization events in which cells escape crisis are frequently correlated with the presence of telomerase activity. We tested the hypothesis that telomerase activation is the critical step in the immortalization process by studying the effects of telomerase activity in two mortal SVLT-Rasval12-transformed human pancreatic cell lines, TRM-6 and betalox5. The telomerase catalytic subunit, hTRT, was introduced into late-passage cells via retroviral gene transfer. Telomerase activity was successfully induced in infected cells, as demonstrated by a telomerase repeat amplification protocol assay. In each of nine independent infections, telomerase-positive cells formed rapidly dividing cell lines while control cells entered crisis. Telomere lengths initially increased, but telomeres were then maintained at their new lengths for at least 20 population doublings. These results demonstrate that telomerase activity is sufficient to enable transformed cells to escape crisis and that telomere elongation in these cells occurs in a tightly regulated manner.  (+info)

Different regulation of the p53 core domain activities 3'-to-5' exonuclease and sequence-specific DNA binding. (3/1802)

In this study we further characterized the 3'-5' exonuclease activity intrinsic to wild-type p53. We showed that this activity, like sequence-specific DNA binding, is mediated by the p53 core domain. Truncation of the C-terminal 30 amino acids of the p53 molecule enhanced the p53 exonuclease activity by at least 10-fold, indicating that this activity, like sequence-specific DNA binding, is negatively regulated by the C-terminal basic regulatory domain of p53. However, treatments which activated sequence-specific DNA binding of p53, like binding of the monoclonal antibody PAb421, which recognizes a C-terminal epitope on p53, or a higher phosphorylation status, strongly inhibited the p53 exonuclease activity. This suggests that at least on full-length p53, sequence-specific DNA binding and exonuclease activities are subject to different and seemingly opposing regulatory mechanisms. Following up the recent discovery in our laboratory that p53 recognizes and binds with high affinity to three-stranded DNA substrates mimicking early recombination intermediates (C. Dudenhoeffer, G. Rohaly, K. Will, W. Deppert, and L. Wiesmueller, Mol. Cell. Biol. 18:5332-5342), we asked whether such substrates might be degraded by the p53 exonuclease. Addition of Mg2+ ions to the binding assay indeed started the p53 exonuclease and promoted rapid degradation of the bound, but not of the unbound, substrate, indicating that specifically recognized targets can be subjected to exonucleolytic degradation by p53 under defined conditions.  (+info)

Association of simian virus 40 with a central nervous system lesion distinct from progressive multifocal leukoencephalopathy in macaques with AIDS. (4/1802)

The primate polyomavirus SV40 is known to cause interstitial nephritis in primary infections and progressive multifocal leukoencephalopathy (PML) upon reactivation of a latent infection in SIV-infected macaques. We now describe a second central nervous system manifestation of SV40: a meningoencephalitis affecting cerebral gray matter, without demyelination, distinct from PML. Meningoencephalitis appears also to be a primary manifestation of SV40 infection and can be seen in conjunction with SV40-induced interstitial nephritis and pneumonitis. The difference in the lesions of meningoencephalitis and PML does not appear to be due to cellular tropism, as both oligodendrocytes and astrocytes are infected in PML and meningoencephalitis, as determined by in situ hybridization or immunohistochemistry for SV40 coupled with immunohistochemistry for cellular determinants. This is further supported by examination of SV40 nucleic acid sequences from the ori-enhancer and large-T-antigen regions, which reveals no tissue-or lesion-specific variation in SV40 sequences.  (+info)

A telomere-independent senescence mechanism is the sole barrier to Syrian hamster cell immortalization. (5/1802)

Reactivation of telomerase and stabilization of telomeres occur simultaneously during human cell immortalization in vitro and the vast majority of human cancers possess high levels of telomerase activity. Telomerase repression in human somatic cells may therefore have evolved as a powerful resistance mechanism against immortalization, clonal evolution and malignant progression. The comparative ease with which rodent cells immortalize in vitro suggests that they have less stringent controls over replicative senescence than human cells. Here, we report that Syrian hamster dermal fibroblasts possess substantial levels of telomerase activity throughout their culture life-span, even after growth arrest in senescence. In our studies, telomerase was also detected in uncultured newborn hamster skin, in several adult tissues, and in cultured fibroblasts induced to enter the post-mitotic state irreversibly by serum withdrawal. Transfection of near-senescent dermal fibroblasts with a selectable plasmid vector expressing the SV40 T-antigen gene resulted in high-frequency single-step immortalization without the crisis typically observed during the immortalization of human cells. Collectively, these data provide an explanation for the increased susceptibility of rodent cells to immortalization (and malignant transformation) compared with their human equivalents, and provide evidence for a novel, growth factor-sensitive, mammalian senescence mechanism unrelated to telomere maintenance.  (+info)

The introduction of dominant-negative p53 mutants suppresses temperature shift-induced senescence in immortal human fibroblasts expressing a thermolabile SV40 large T antigen. (6/1802)

Immortal human fibroblasts, SVts8 cells, which express a heat-labile SV40 large T antigen, induces a senescence-like phenomenon in response to upward shift in temperature. Cells with arrested division show strong induction of senescence-associated beta-galactosidase. We examined how p53 and pRB are involved in this phenomenon since they are major targets of the T antigen. Transfection of cells with plasmids encoding the wild-type T antigen or human papilloma virus type 16 E6/E7 proteins completely abolished the arrest in cell division, a plasmid encoding the E6 protein suppressed it markedly, while a plasmid encoding E7 had no effect. Plasmids encoding dominant-negative p53 mutants also suppressed the arrest in cell division to various degrees. Upon temperature shift, p21 mRNA was upregulated 10-fold in SVts8 cells, but only slightly in clones expressing the wild-type T antigen or dominant-negative p53 mutants. These data demonstrate that p53 plays a major role in this senescence-like phenomenon.  (+info)

Overexpression of D-type cyclins, E2F-1, SV40 large T antigen and HPV16 E7 rescue cell cycle arrest of tsBN462 cells caused by the CCG1/TAF(II)250 mutation. (7/1802)

tsBN462 cells, which have a point mutation in CCG1/TAF(II)250, a component of TFIID complex, arrest in G1 at the nonpermissive temperature of 39.5 degrees C. Overexpression of D-type cyclins rescued the cell cycle arrest of tsBN462 cells, suggesting that the cell cycle arrest was through Rb. Consistent with this, overexpression of E2F-1, whose function is repressed by the hypophosphorylated form of Rb, also rescued the cell cycle arrest. Moreover, expression of the viral oncoproteins SV40 large T antigen and HPV16 E7, which both bind Rb and inactivate its function, rescued the cell cycle arrest, whereas HPV16 E6 did not. Mutation of the Rb-binding motif in E7 abrogated its ability to rescue the cell cycle arrest. Expression of exogenous cyclin D1, SV40 large T antigen or CCG1/TAF(II)250 increased cyclin A expression at 39.5 degrees C. Coexpression of HPV16 E7 and adenovirus E1b19K, which blocks apoptosis, rescued the proliferation of tsBN462 cells at 38.5 degrees C. To investigate the mechanism underlying the lack of cyclin D1 expression, deletion analysis of cyclin D1 promoter was performed. The 0.15 kbp cyclin D1 core promoter region, which lacks any transcription factor binding motifs, still exhibited a temperature-sensitive phenotype in tsBN462 cells suggesting that CCG1/TAF(II)250 is critical for the function of the cyclin D1 core promoter.  (+info)

Concerted expression of BK virus large T- and small t-antigens strongly enhances oestrogen receptor-mediated transcription. (8/1802)

Previous studies have shown that the human polyomavirus BK (BKV) genome contains an oestrogen response element (ERE). This isolated element binds its cognate receptor in vitro and can mediate 17beta-oestradiol-induced gene expression when linked to a heterologous promoter. The roles of the ERE- and the AP-1-binding sites in oestrogen receptor-directed transcription from the complete BKV promoter/enhancer (Dunlop strain) have been examined and the effects of the general co-activator CBP and large T- and small t-antigens on oestrogen receptor-mediated transcription have been investigated. A constitutive activated oestrogen receptor stimulated BKV promoter activity in HeLa cells. Mutations in either the ERE- or the AP-1-binding sites did not impair oestrogen receptor-induced activation of the BKV Dunlop promoter, while mutations in both binding motifs almost completely abolished oestrogen receptor-induced transcription. Simultaneous expression of large T- and small t-antigens strongly activated oestrogen receptor-mediated transcription. When expressed separately, only large T-antigen moderately stimulated oestrogen receptor-mediated transcription. The stimulatory effect of large T-antigen on the activity of the oestrogen receptor is probably indirect because no physical interaction between the two proteins was detected in a two-hybrid assay. Large T-antigen abrogated the synergistic effect on transcription between this nuclear receptor and the general co-activator CBP. The findings that the BKV early proteins amplify oestrogen receptor-mediated transcription may have important biological implications in individuals with raised oestrogen concentrations.  (+info)

PubMed comprises more than 30 million citations for biomedical literature from MEDLINE, life science journals, and online books. Citations may include links to full-text content from PubMed Central and publisher web sites.
Molecular Oncology Program, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL 33612, USA. Signal transducers and activators of transcription (STATs) were originally identified as key components of signaling pathways involved in mediating responses to IFNs. Previous studies showed that the Src oncoprotein constitutively activates one STAT family member, Stat3. In this study, we investigated STAT activation in a panel of rodent fibroblast cell lines stably transformed by diverse viral oncoproteins. Using a temperature-sensitive mutant of v-Src, we determined that Stat3 is activated within 15 min of shift from nonpermissive to permissive temperature for cell transformation. This finding indicates that v-Src tyrosine kinase activity is required for Stat3 activation and suggests that Stat3 is proximal to signaling initiated by Src. In addition, Stat3 activation is induced by another nonreceptor tyrosine kinase, v-Fps; by polyoma virus middle T antigen, which activates Src family kinases; ...
Recent analyses have suggested that many genes possess multiple transcription start sites (TSSs) that are differentially utilized in different tissues and cell lines. We have identified a huge number of TSSs mapped onto the mouse genome using the cap analysis of gene expression (CAGE) method. The standard hierarchical clustering algorithm, which gives us easily understandable graphical tree images, has difficulties in processing such huge amounts of TSS data and a better method to calculate and display the results is needed. We use a combination of hierarchical and non-hierarchical clustering to cluster expression profiles of TSSs based on a large amount of CAGE data to profit from the best of both methods. We processed the genome-wide expression data, including 159,075 TSSs derived from 127 RNA samples of various organs of mouse, and succeeded in categorizing them into 70-100 clusters. The clusters exhibited intriguing biological features: a cluster supergroup with a ubiquitous expression profile,
848 Recapitulating human disease in a genetically engineered mouse (GEM) has become an important source for understanding human tumorigenesis and evaluating novel therapeutic approaches. Furthermore, molecular expression profiling of tumors has increased our understanding of the molecular diversity of disease and classification of tumors. Since many cancers involve mutations in the tumor suppressor genes p53 and the retinoblastoma (Rb), which deregulate the cell cycle, apoptotic mechanisms, and genomic stability, relevant GEM models which functionally inactive these genes through the expression of the Simian Virus 40 T-antigen (Tag) have been developed for human prostate, breast and lung carcinomas. Expression profiles from three types of GEM tumors have been analyzed to identify both common and tumor-specific gene expression signatures for these three types of epithelial tumors. Mammary tumors were derived from C3(1)/Tag transgenic mice, prostate tumors came from probasin/Tag (TRAMP) mice, and ...
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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.
FOR BULK ORDER REQUESTS PLEASE CONTACT US Description :Full-length recombinant human PCTK3 (CDK18) and Cyclin Y (2-end) were co-expressed by baculovirus in Sf9 insect cells using N-terminal GST tags. Species :Human Tag :GST tags Expression System:Sf9 insect cells using baculovirus Sequence :PCTK3 (CDK18)(Full length) a
FOR BULK ORDER REQUESTS PLEASE CONTACT US Description :Recombinant human RET/PTC3, the fusion protein [NCOA4 (1-238)-RET (713-end)], was expressed by baculovirus in Sf9 insect cells using an N-terminal GST tag. Species :Human Tag :GST tag Expression System:Sf9 insect cells using baculovirus Sequence :NCOA4 (1-238)-RET
Cells were derived by infection of hTERT-HPNE E6/E7 cells (ATCC CRL-4036) with retroviral vector (pBabeZeo) carrying the SV40 small t antigen
Tangram Brain teasers for kids, teens, and adults. Tangram Puzzle, IQ training STEM toys - Level 4 T4 - Challenging level: 8/10 - For Challenge Lovers and Advanced players POWER UP YOUR BRAIN! Consists of 4 polygonal pieces, 46 stages of playing The Small T© is a one-of-a-kind puzzle for 2 reasons Innovative polygon s
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Abstract: Abstract Polyomaviruses have provided many insights into control of cell physiology. Studies of their tumor antigens (Tags) have led to appreciation of the role of tyrosine phosphorylation, PI3K and p53 in oncogenic transformation. This work explores signal pathways regulated by polyomavirus small T antigen (PyST) that control differentiation and regulate cell survival in fat, muscle and... read more bone models. Comparisons of murine polyomavirus ST (PyST) to monkey polyomavirus SV40 (SV40 ST) have been especially useful in parsing out the mechanisms involved. This work also makes use of PyST mutants defective in specific interactions. Of the many PyST functions, we particularly illustrate the importance of phosphatase 2A (PP2A) for PyST to regulate differentiation. PP2A regulates almost all cell signaling pathways. The holoenzyme consists of a catalytic C subunit and one of many regulatory B subunits bound to an A scaffolding subunit. Of more than 80 PP2A isoforms, 10% use Abeta as a ...
TY - JOUR. T1 - Progression of familial adenomatous polyposis (FAP) colonic cells after transfer of the src or polyoma middle T oncogenes. T2 - Cooperation between src and HGF/Met in invasion. AU - Empereur, S.. AU - Djelloul, S.. AU - Di Gioia, Y.. AU - Bruyneel, E.. AU - Mareel, M.. AU - Van Hengel, J.. AU - Van Roy, F.. AU - Comoglio, P.. AU - Courtneidge, S.. AU - Paraskeva, C.. AU - Chastre, E.. AU - Gespach, C.. N1 - Funding Information: We gratefully acknowledge Dr Piwnica-Worms (Harvard Medical School, Beth Israel Hospital, Boston, USA) for providing the expression vectors pLJ, pLJ(C) and pLJ(527), Dr S Dilworth (RPMS, Hammersmith Hospital, London, UK) for the generous gift of the PAb 762. This work was supported by research grants and doctoral fellowships (S E and S D) from the Association de la Recherche Contre le Cancer (ARC) and la Ligue Nationale Contre le Cancer.. PY - 1997. Y1 - 1997. N2 - Little is known about the the signalling pathways driving the adenoma-to-carcinoma sequence ...
1039 Thrombospondin-1 (TSP-1) has been shown to be an effective anti-angiogenic and anti-tumorigenic protein in vitro and in many xenograft mouse models. These models are limited in the information they provide because they dont recapitulate the natural progression of the tumor at the correct body site. We were interested to know how TSP-1 affects breast cancer progression in vivo. The approach we decided to take was to develop a transgenic mouse model for breast cancer in order to enable us to study tumor progression at different stages (ie. initiation to metastasis). We crossed TSP-1 +/+ and TSP-1 -/- female mice with male polyomavirus middle T Antigen (PyT)/mouse mammary tumor virus (MMTV) transgenic mice to generate progeny that are PyT +/-, TSP-1 +/+ and PyT +/-, TSP-1-/-. At 60 days of age when tumors are becoming palpable, we found that tumors in the PyT +/-, TSP-1 -/- mice are 35% larger than tumors found in the PyT +/-, TSP-1+/+. In our preliminary analysis on blood vessel density, ...
The oligomers formed by a mutant nonkaryophilic large T antigen of simian virus 40, which lacks residues 110 through 152 of normal large T antigen and transforms only established cells (L. Fischer-Fantuzzi and C. Vesco, Proc. Natl. Acad. Sci. USA 82:1891-1895, 1985), were found to consist predominantly of dimers. Anti-p53 antibodies precipitated 14 to 16S complexes containing the mutant nonkaryophilic large T antigen and p53 from extracts of transformed cells, and anti-p53 indirect immunofluorescence stained these cells in the cytoplasm. ...
Buy our Recombinant Simian Virus 40 (SV40) SV40 Large T Antigen protein. Ab82118 is a full length protein produced in Baculovirus and has been validated in…
Cerebral cortical development requires orderly transitions between neurogenesis and differentiation. Neurogenesis also results in overproduction of neurons that are selectively targeted for apoptosis. In these experiments, we conditionally immortalized (Almazan and McKay, 1992; Yanai and Obinata, 1994; Taher et al., 1995; Eves et al., 1996) neural precursors from embryonic rat cerebral cortex, to contrast estrogen and neurotrophin regulation of p53-dependent cortical differentiation and death.. The large T antigen promotes mammalian cell cycle by inhibiting checkpoint transcription factors like p53 (for review, see Levine, 1997). Consequently, the Ts/U19 large T antigen mutation permits synchronization of differentiation, by conditionally regulating p53-dependent mechanisms. At the nonpermissive temperature (39°C), large T antigen expression ceases and substantial cell death occurs, that is partly caused by apoptosis. At this temperature, we also observed induction of pp53 and p53-dependent ...
TY - JOUR. T1 - Immortalization of subpopulations of respiratory epithelial cells from transgenic mice bearing SV40 large T antigen. AU - Ikeda, K.. AU - Clark, J. C.. AU - Bachurski, C. J.. AU - Wikenheiser, K. A.. AU - Cuppoletti, J.. AU - Mohanti, S.. AU - Morris, R. E.. AU - Whitsett, J. A.. PY - 1994. Y1 - 1994. UR - http://www.scopus.com/inward/record.url?scp=0028041963&partnerID=8YFLogxK. UR - http://www.scopus.com/inward/citedby.url?scp=0028041963&partnerID=8YFLogxK. M3 - Article. AN - SCOPUS:0028041963. VL - 267. JO - American Journal of Physiology - Heart and Circulatory Physiology. JF - American Journal of Physiology - Heart and Circulatory Physiology. SN - 0363-6135. IS - 3 part 1. ER - ...
TY - JOUR. T1 - Further characterisation of the complex containing middle T antigen and pp60.. AU - Courtneidge, Sara. PY - 1989. Y1 - 1989. UR - http://www.scopus.com/inward/record.url?scp=0024387934&partnerID=8YFLogxK. UR - http://www.scopus.com/inward/citedby.url?scp=0024387934&partnerID=8YFLogxK. M3 - Article. C2 - 2477198. AN - SCOPUS:0024387934. VL - 144. SP - 121. EP - 128. JO - Current Topics in Microbiology and Immunology. JF - Current Topics in Microbiology and Immunology. SN - 0070-217X. ER - ...
PubMed comprises more than 30 million citations for biomedical literature from MEDLINE, life science journals, and online books. Citations may include links to full-text content from PubMed Central and publisher web sites.
Deppert, W and Walter, G, Domains of simian virus 40 large t-antigen exposed on the cell surface. (1982). Subject Strain Bibliography 1982. 3601 ...
Most of the data on which we base our prostate cancer screening practices is indirect and not definitively linked to the decrease in mortality that has been observed.
Nuclear targeting sequences are essential for the transport of proteins into the nucleus. The seven-amino-acid nuclear targeting sequence of the SV40 large T antigen has been regarded as the model; however, many nuclear targeting sequences appear to be more complex. We suggest in this review that, d …
Cancers that display a specific combination of sugars, called T-antigen, are more likely to spread through the body and kill a patient. However, what regulates the appearance of T-antigen in cancer cells, the set of proteins modified with T-antigen, and the roles the T-antigen and the modified proteins play during metastasis, is not yet understood.
generating the core 1 O-glycan Gal-beta1-3GalNAc-alpha1-Ser/Thr (T antigen), which is a precursor for many extended O-glycans in ...
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Simian virus (SV40) large T antigen, molecular model. This antigen is from the simian vacuolating virus 40 (SV40). Large T antigens play a role in regulating the viral life cycle of the polyomaviridae viruses, such as SV40. SV40 is found in monkeys such as Rhesus monkeys and macaques. Potentially tumour-causing in primates and humans, it is used in laboratory research and in vaccines. - Stock Image C025/1808
The ability of normal mice to mount an SV40 T antigen-specific cytolytic T lymphocytes response when immunized in vivo with splenocytes from the SV40 T antigen transgenic 427-line mice and restimulated in vitro with SV40-transformed fibroblasts, or when immunized with SV40 and restimulated with 427-line splenocytes, was analyzed. Both immunization schemes resulted in an SV40 T antigen-specific immune response, indicating the presence of SV40 T antigen-positive cells in the spleens of these transgenic mice. Normal mice engrafted with skin from 427 donors showed no rejection of the graft. Thus, SV40 T antigen in transgenic 427-line mice is expressed on an undefined cell type in the spleen and acts as a tissue-specific minor histocompatibility antigen.
The simian virus 40 small T-associated 56,000-Mr (56K) and 32K cellular proteins were shown to be closely related to the polyomavirus medium T-associated 61K and 37K cellular proteins as demonstrated by two-dimensional polyacrylamide gel electrophoresis and V8 protease peptide mapping. ...
DELETION OF THE CARBOXY TERMINUS OT SIMIAN VIRUS 40 LARGE T ANTIGEN AFFECTS VIRAL LATE GENE EXPRESSION A Thesis Submitted to the Faculty in partial fulfillment of the requirements for the degree of Doctor of Philosophy Terryl Stacy DARTMOUTH COLLEGE Hanover, New Hampshire March 8,1990 ...
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Looking for online definition of T-antigen in the Medical Dictionary? T-antigen explanation free. What is T-antigen? Meaning of T-antigen medical term. What does T-antigen mean?
Oncogenes of DNA tumor viruses encode proteins that cause cells to divide incessantly, eventually leading to formation of a tumor. These oncoproteins have now been found to antagonize the innate immune response of the cell (link to paper).. Most cells encountered by viruses are not dividing, and hence do not efficiently support viral DNA synthesis. The genomes of adenoviruses, polyomaviruses, and papillomaviruses encode proteins that cause cells to divide. This effect allows for efficient viral replication, because a dividing cell is producing the machinery for DNA synthesis. Under certain conditions, infections by these viruses do not kill cells, yet they continue to divide due to the presence of viral oncoproteins. Such incessant division gives the cells new properties - they are called transformed cells - and they may eventually become a tumor.. These so-called viral oncoproteins include large T antigen (of SV40, a polyomavirus); E6 and E7 (papillomavirus), and E1A (adenovirus). These viral ...
This topic contains 11 study abstracts on Simian virus 40 (SV40) indicating it may contribute to Simian virus 40 (SV40), Mesothelioma, and Cancer Metastasis
Kupffer cells have been isolated from transgenic mice carrying a thermolabile SV40 large tumor antigen under the H2Kb promoter (kind gift of D. Kioussis, NIMR, London). The cells grow with Interferon-gamma at 33oC, at which temperature the promoter is turned on and the SV40T Ag is active. They differentiate at 39oC. These cells are now being characterised: cytokine and NO liberation is stimulated, surface receptors are assessed at the mRNA and protein level, and phagocytosis and uptake of bacterial components are being measured. Results will be compared with the functional characteristics of primary Kupffer cells isolated from normal mice (see also 3R project 73-00) Conclusions and Relevance for 3R ...
in Research in Veterinary Science (2009), 87(1), 123-32. In the present study we developed an enzymatic approach (through the use of collagenase and dispase) to isolate bovine intestinal epithelial cells. Using this method, freshly isolated jejunocytes could be ... [more ▼]. In the present study we developed an enzymatic approach (through the use of collagenase and dispase) to isolate bovine intestinal epithelial cells. Using this method, freshly isolated jejunocytes could be distinguished from simultaneously isolated colonocytes, as the jejunocytes specifically exhibited the small intestinal peptidase gene transcript, as well as an active alkaline phosphatase. The transformation of both types of cell suspension was performed by retroviral infection, using reproduction-defective viruses bearing the gene coding for the large T antigen of the leukaemia simian virus (SV40). The success of the transfection was demonstrated by (1) a significant increase in cell passage numbers (52-53 vs. 7 passages ...
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Hintergrund und Fragestellung: Die Etablierung von humanen Zellinien wurde bisher häufig limitiert durch die in der Regel nach einigen Passagen auftretende Krise der Zellen in Kultur. Zur...
Transgenic mice were generated using a construct that encodes mouse polyoma virus large T antigen, one of three oncogenic products of the early region of the polyoma viral genome. Of 16 transgenic families developed, 1 was characterized by a neurologic disorder consisting of constant tremor and recurrent seizures. Morphologic analysis of the central nervous system (CNS) of affected transgenic mice included: classical light and electron microscopic examination; immunohistochemical assessment of the presence and localization of myelin-specific proteins, of the astrocyte marker glial fibrillary acidic protein, of the oligodendrocyte marker galaetosyl cerebro-side, and of large T; double immunolabeling of glial fibrillary acidic protein or galactosyl cerebro-side and large T to identify the CNS cell type in which large T is expressed; and in situ hybridization to study myelin basic protein gene expression. Our results suggest that polyoma large T is expressed in astrocytes, possibly resulting in ...
Marine mammals, such as whales, have a high proportion of body fat and so are susceptible to the accumulation, and associated detrimental health effects, of lipophilic environmental contaminants. Recently, we developed a wild-type cell line from humpback whale fibroblasts (HuWa). Extensive molecular assessments with mammalian wild-type cells are typically constrained by a finite life span, with cells eventually becoming senescent. Thus, the present work explored the possibility of preventing senescence in the HuWa cell line by transfection with plasmids encoding the simian virus large T antigen (SV40T) or telomerase reverse transcriptase (TERT). No stable expression was achieved upon SV40 transfection. Transfection with TERT, on the other hand, activated the expression of telomerase in HuWa cells. At the time of manuscript preparation, the transfected HuWa cells (HuWaTERT) have been stable for at least 59 passages post-transfection. HuWaTERT proliferate rapidly and maintain initial cell ...
Human polyomaviruses (JC virus, BK virus and simian virus 40) are causative agents of some human diseases and, interestingly, are involved in processes of cell transformation and oncogenesis. These viruses need the cell cycle machinery of the host cell to complete their replication; so they evolved mechanisms that can interfere with the growth control of infected cells and force them into DNA replication. The retinoblastoma family of proteins (pRb), which includes pRb/p105, p107 and pRb2/p130, acts as one of the most important regulators of the G1/S transition of the cell cycle. Rb proteins represent an important target for viral oncoproteins. Early viral T antigens can bind all members of the pRb family, promoting the activation of the E2F family of transcription factors, thus inducing the expression of genes required for the entry to the S phase. The interaction between early viral antigens and cell cycle regulators represents an important mechanism through which viruses deregulate cell cycle ...
WU polyomavirus is a recently described polyomavirus found in patients with respiratory infections. Of 2,637 respiratory samples tested in St. Louis, Missouri, 2.7% were positive for WU polyomavirus by PCR, and 71% were coinfected with other respiratory viruses. Persistent human infection with WU polyomavirus is described ...
TY - JOUR. T1 - Protection from tumor recurrence following adoptive immunotherapy varies with host conditioning regimen despite initial regression of autochthonous murine brain tumors. AU - Cozza, Eugene M.. AU - Cooper, Timothy K.. AU - Budgeon, Lynn R.. AU - Christensen, Neil D.. AU - Schell, Todd D.. PY - 2015/2/26. Y1 - 2015/2/26. N2 - Adoptive T cell transfer (ACT) has achieved clinical success in treating established cancer, particularly in combination with lymphodepleting regimens. Our group previously demonstrated that ACT following whole-body irradiation (WBI) promotes high-level T cell accumulation, regression of established brain tumors, and long-term protection from tumor recurrence in a mouse model of SV40 T antigen-induced choroid plexus tumors. Here we asked whether an approach that can promote strong donor T-cell responses in the absence of WBI might also produce this dramatic and durable tumor elimination following ACT. Agonist anti-CD40 antibody can enhance antigen-specific ...
Abstract Background The mammary glands of pigs share many functional and morphological similarities with the breasts of humans, raising the potential of their utility for research into the mechanisms underlying normal mammary function and breast carcinogenesis. Here we sought to establish a model for the efficient manipulation and transformation of porcine mammary epithelial cells (pMEC) in vitro and tumor growth in vivo. Methods We utilized a vector encoding the red florescent protein tdTomato to transduce populations of pMEC from Yorkshire -Hampshire crossbred female pigs in vitro and in vivo. Populations of primary pMEC were then separated by FACS using markers to distinguish epithelial cells (CD140a-) from stromal cells (CD140a+), with or without further enrichment for basal and luminal progenitor cells (CD49f+). These separated pMEC populations were transduced by lentivirus encoding murine polyomavirus T antigens (Tag) and tdTomato and engrafted to orthotopic or ectopic sites in ...
Using the TCGA data set for malignant melanoma, the patients were segregated according to the presence or absence of the T cell-inflamed gene expression signature in the tumor microenvironment. Transcriptional profiling revealed no differences in the levels of cancer-testis (CT) antigens or differentiation antigens between the hot and the cold tumors. Using exome sequencing of tumor versus germline, a range of 18 to 3001 of non-synonymous mutations was observed in both cohorts. Using the syfpeithi algorithm for HLA-A*0201 patients, a median of 123 mutations having a high immunogenicity score were found in the T cell-inflamed cohort versus 176 in the non-T cell-inflamed. To confirm actual immunogenicity, 321 peptides from hot tumors and 409 peptides from cold tumors have been synthesized. Using a high-throughput T2 binding assay, peptides from both cohorts were found to bind to HLA-A*0201. In vitro priming of T cells using autologous dendritic cells also revealed that peptides from both cohorts ...
We have obtained transgenic mice in which an erythropoietin-SV40 virus T antigen fusion gene is homologously recombined into the native Epo locus. This gene is expressed in a tissue-specific manner closely resembling that of the native Epo gene. Immunohistochemical detection of SV40 T antigen has been used to characterize the hepatic cell populations expressing the transgene. In mice stimulated by anaemia or hypobaric hypoxia, SV40 T antigen was demonstrated in two liver cell populations: a subset of hepatocytes and a nonparenchymal cell type. Immunohistochemical and ultrastructural characterization of these cells by light and electron microscopy showed the nonparenchymal cell type to be the Ito cells, which lie in a persinusoidal position within the space of Disse. We therefore conclude that Ito cells are the nonhepatocytic source of liver Epo production. These cells show many similarities to the Epo-producing fibroblastoid interstitial cells of the kidney.
Here, we demonstrated the feasibility of a chemical synthetic lethality screen in cultured MEFs using a double-label fluorescence system. The major challenge in the present work has been to identify a replicon that can stably replicate in MEFs while under selection and decay spontaneously at a reasonable rate on removal of selection pressure. Our initial attempt, which employed polyoma virus replicons, failed. These replicons, containing wild-type or mutated enhancer/origin of DNA replication and encoding polyoma large T antigen, were shown previously to be capable of replicating in either somatic mouse cells (16) or pluripotent embryonal mouse cells such as EC cells (17, 18) or mouse ES cells (19), respectively. However, we found out that these polyoma-based replicons could not replicate in MEFs, which are late embryonal mouse cells. In contrast, employment of the EBV-based episomal survival plasmid, previously used in human cells (13), turned out to be suitable for synthetic lethality ...
Resveratrol exhibits a strong cytotoxic activity in cultured cells and has an antiviral action against polyomavirus: potential clinical use. . Biblioteca virtual para leer y descargar libros, documentos, trabajos y tesis universitarias en PDF. Material universiario, documentación y tareas realizadas por universitarios en nuestra biblioteca. Para descargar gratis y para leer online.
This is a clone of the SV40LT-SMC cell line derived from primary abdominal aortic tissue from young rats. The parental line was created by immortalizing the primary cells by transfection with SV40 large T antigen.
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Courtneidge, Sara A.; Smith, Alan E. (2 June 1983). "Polyoma virus transforming protein associates with the product of the c- ... The genes for the small tumor antigen (STag), middle tumor antigen (MTag), and large tumor antigen (LTag) are encoded in the " ... the small tumor antigen and large tumor antigen. MTag occurs only in a few known polyomaviruses, while STag and LTag are ... The middle tumor antigen (also called the middle T-antigen and abbreviated MTag or MT) is a protein encoded in the genomes of ...
... the cause of infectious laryngotracheitis in poultry SV40 large T antigen, a proto-oncogene derived from polyomavirus SV40 Heat ... Laplace transform Less than Logic Theorist, a computer program written in 1955-56 to prove mathematical theorems; called "the ...
... in which MMTV-LTR is used to drive the expression of mammary gland specific polyomavirus middle T-antigen, leading to a rapid ... Siegel, P. M.; Shu, W; Cardiff, R. D.; Muller, W. J.; Massagué, J (2003). "Transforming growth factor beta signaling impairs ... Guy, C. T.; Cardiff, R. D.; Muller, W. J. (1992). "Induction of mammary tumors by expression of polyomavirus middle T oncogene ... The role of autocrine transforming growth factor beta 1(TGF-β1) signaling on motility and survival in PymT cells derived from ...
In the summer of 1979, studies of polyomavirus middle T and v-Src associated kinase activities led to the discovery of tyrosine ... Protein phosphorylation Eckhart W, Hutchinson MA, Hunter T (1979). "An activity phosphorylating tyrosine in polyoma T antigen ... 2012). "N-terminal tyrosine phosphorylation of caveolin-2 negates anti-proliferative effect of transforming growth factor beta ... that negatively regulates the anti-proliferative function of transforming growth factor beta (TGF-beta) in endothelial cells. ...
"Differential tumorigenicity of 3T3 cells transformed in vitro with polyoma virus and in vivo selection for high tumorigenicity ... One such antigen was MAGE-A1. The coexistence of a progressing melanoma with melanoma-specific T cells implicitly does not ... CAFs can also secrete transforming growth factor beta (TGF-β), which is associated with EMT, a process by which cancer cells ... As many fibroblasts are transformed into CAFs during carcinogenesis, this reduces the amount of ECM produced and the ECM that ...
... acutely transforming or slowly transforming. In acutely transforming viruses, the viral particles carry a gene that encodes for ... Merkel cell polyomavirus - a polyoma virus - is associated with the development of Merkel cell carcinoma[27] ... 1987: Hepatitis C virus, or HCV, discovered by panning a cDNA library made from diseased tissues for foreign antigens ... slowly transforming viruses have very long tumor latency compared to acutely transforming viruses, which already carry the ...
T antigen mutations are a human tumor-specific signature for Merkel cell polyomavirus. Proceedings of the National Academy of ... an obsolete term originally used for acutely transforming retroviruses). The development of cancer is determined by a variety ... The most recently discovered human cancer virus is a polyomavirus (Merkel cell polyomavirus) that causes most cases of a rare ... Merkel cell polyomavirus closely related to SV40 and mouse polyomaviruses that have been used as animal models for cancer ...
E7 (in oncogenic HPVs) acts as the primary transforming protein. E7 competes for retinoblastoma protein (pRb) binding, freeing ... Overall, these DNA-based studies, combined with measurements of type-specific antibodies against HPV capsid antigens, have ... Because the process of transforming normal cervical cells into cancerous ones is slow, cancer occurs in people having been ...
In addition, Stat3 activation is induced by another nonreceptor tyrosine kinase, v-Fps; by polyoma virus middle T antigen, ... In contrast SV40 large T antigen, which transforms cells through different mechanisms, and the v-Ras and v-Raf oncoproteins, ... Lessons in Signaling and Tumorigenesis from Polyomavirus Middle T Antigen. Microbiol. Mol. Biol. Rev., September 1, 2009; 73(3 ... In this study, we investigated STAT activation in a panel of rodent fibroblast cell lines stably transformed by diverse viral ...
Polyomavirus Transforming" by people in this website by year, and whether "Antigens, Polyomavirus Transforming" was a major or ... Antigens, Polyomavirus Transforming*Antigens, Polyomavirus Transforming. *Polyomavirus Tumor Antigens. *Antigens, Polyomavirus ... "Antigens, Polyomavirus Transforming" is a descriptor in the National Library of Medicines controlled vocabulary thesaurus, ... Below are the most recent publications written about "Antigens, Polyomavirus Transforming" by people in Profiles. ...
Polyomavirus Infections/complications*. Substance. *Antigens, Polyomavirus Transforming. LinkOut - more resources. Full Text ... Polyomavirus in human cancer development.. Lee W1, Langhoff E.. Author information. 1. Mount Sinai Medical School, New York, ... In animal studies, polyoma viruses have been found to be viral agents for oncogenesis and to produce a wide range of ... The human polyoma viruses (JCV and BKV), along with their simian cousin (SV40), are ubiquitous viruses that are primarily ...
Courtneidge, Sara A.; Smith, Alan E. (2 June 1983). "Polyoma virus transforming protein associates with the product of the c- ... The genes for the small tumor antigen (STag), middle tumor antigen (MTag), and large tumor antigen (LTag) are encoded in the " ... the small tumor antigen and large tumor antigen. MTag occurs only in a few known polyomaviruses, while STag and LTag are ... The middle tumor antigen (also called the middle T-antigen and abbreviated MTag or MT) is a protein encoded in the genomes of ...
Antigens, Polyomavirus Transforming / metabolism * Base Sequence * CDC2-CDC28 Kinases* * Cell Cycle* * Cloning, Molecular / ... Cotransfection experiments indicate that CIP1 and SV40 T antigen function in a mutually antagonistic manner to control cell ...
Antigens, Polyomavirus Transforming / genetics* * Base Composition * Base Sequence * Cell-Free System * Codon ... we performed replication reactions using a HeLa cell extract and the SV40 large T antigen. Frameshifts that restore the reading ...
... as a target for signal transduction events leading from polyomavirus middle tumor antigen (mT). Two partially transforming ... In the polyomavirus systems, the latter requires integration of signals from mT involving both Shc and PI3K. ... Infection of mouse fibroblasts by wild-type polyomavirus results in increased phosphorylation of ribosomal protein S6 (D.A. ... Association of Polyomavirus middle tumor antigen with phospholipase C-gamma 1.. *Wei Su, Wanli Liu, Brian S. Schaffhausen, ...
Cellular transformation by Simian Virus 40 and Murine Polyoma Virus T antigens.. Cheng J1, DeCaprio JA, Fluck MM, Schaffhausen ... While PY also encodes LT and ST, the unique middle T (MT) generates most of the transforming activity. SV40 LT mediated ... Cellular Transformation by Simian Virus 40 and Murine Polyoma Virus T antigens ... Cellular Transformation by Simian Virus 40 and Murine Polyoma Virus T antigens ...
Polyomavirus Transforming Antigens Medicine & Life Sciences View full fingerprint Cite this. * APA ... Strikingly, T-cell responses against the two oncogenic MCPyV proteins Large T antigen and small T antigen were exclusively ... Strikingly, T-cell responses against the two oncogenic MCPyV proteins Large T antigen and small T antigen were exclusively ... Strikingly, T-cell responses against the two oncogenic MCPyV proteins Large T antigen and small T antigen were exclusively ...
... is distinguished among polyomaviruses for combining productive infection with cell-transforming properties. In the research ... Characterization of T Antigens, Including Middle T and Alternative T, Expressed by the Human Polyomavirus Associated with ... The polyomavirus tumor (T) antigens play crucial roles in viral replication, transcription, and cellular transformation. They ... and alternative T antigen (ALTO) in TSPyV. So far, none of the human polyomaviruses was shown to express MT, which is ...
Polyomavirus middle T antigen fails to override a p53 growth arrest (18) and also fails to transform REF52 cells unless p53 is ... 1979) T antigen is bound to a host protein in SV40-transformed cells. Nature 278:261-263. ... 1994) The transforming activity of simian virus 40 large tumor antigen. Biochim. Biophys. Acta 1198:65-83. ... 1989) Association of a cellular heat shock protein with simian virus 40 large T antigen in transformed cells. J. Virol. 63:3961 ...
Antigens, Polyomavirus Transforming/physiology. *Cell Line, Transformed. *Cell Transformation, Viral. *Dose-Response ...
Fluorescently labeled murine mammary carcinoma cells, isolated from either MMTV-PyVmT transforming growth factor-beta receptor ... Transforming growth factor beta (TGF-β) has a dual role during tumor progression, initially as a suppressor and then as a ... of TGF-β signaling in mammary carcinoma cells expressing either the c-Neu transgene or the polyoma virus middle T antigen ( ... Transforming growth factor-beta receptor II control (TβRIIfl/fl) cells were used as a control for active transforming growth ...
How might MCV cause Merkel cell carcinoma? Expression of the viral protein known as T antigen might be sufficient to transform ... Merkel cell polyomavirus, a new oncogenic human virus?. None of the four human polymaviruses that were known in early 2008 - JC ... TWiV 214: This is your brain on polyomavirus. On episode #214 of the science show This Week in Virology, Vincent, Alan, and ... Frequent Human Infection with WU and KI Polyomaviruses. Rabies in China. Increased Host Species Diversity and Decreased ...
Association of p60fyn with middle tumor antigen in murine polyomavirus-transformed rat cells. I D Horak, T Kawakami, F Gregory ... Mutational analysis of polyomavirus small-T-antigen functions in productive infection and in transformation. I Martens, S A ... Structure, origin, and transforming activity of feline leukemia virus-myc recombinant provirus FTT. D L Doggett, A L Drake, V ... Avian erythroblastosis virus transforms a novel mast cell-basophil precursor target in the Japanese quail. M G Moscovici, M L ...
... derived from the rat embryo fibroblasts immortalized by the polyoma virus T-antigen (LT) gene and transformed by HPV18 E6 and ... The quantity of p53 protein in cell clones did not correlate with the level of polyoma virus large T-antigen expression. ... THE STATE OF IMMORTALIZED, TRANSFORMING AND SUPPRESSOR GENES IN RAT-CELLS, TRANSFECTED BY POLYOMAVIRUS LARGE-T AND HPV18 E6+E7 ... KOMISSAROVA E, SOYFER M, PAVLOVA L and KISSELJOV F: THE STATE OF IMMORTALIZED, TRANSFORMING AND SUPPRESSOR GENES IN RAT-CELLS, ...
These so-called viral oncoproteins include large T antigen (of SV40, a polyomavirus); E6 and E7 (papillomavirus), and E1A ( ... Another commonly used transformed cell line is 293 (human embryonic kidney cells transformed by adenovirus E1A). Its been ... Cells transformed with T, E6/E7, or E1A proteins are commonly used in laboratories because they are immortal. An example is the ... These new transformed cells failed to respond to cytoplasmic DNA.. Cytoplasmic DNA is detected in cells by an enzyme called ...
Antigens, Polyomavirus Transforming. *Autoimmune Diseases/immunology. *Blood Glucose/metabolism. *Crosses, Genetic. *Female ... Self antigens expressed by solid tumors Do not efficiently stimulate naive or activated T cells: implications for immunotherapy ... Self antigens expressed by solid tumors Do not efficiently stimulate naive or activated T cells: implications for immunotherapy ... The simian virus 40 T antigen (Tag) expressed under the control of the rat insulin promoter (RIP) induced pancreatic beta-cell ...
... such as the simian virus 40 small t antigen and the polyomavirus small and middle T antigens (13). Adenovirus E4orf4, however, ... Because E4orf4 induces apoptosis in transformed cells and reduces colony formation by transformed cells (5), we asked whether ... Because transformed cells are susceptible to E4orf4-induced apoptosis, cellular transformation may be prevented in the presence ... Recently, we and others have shown that E4orf4 protein induces p53-independent apoptosis in several transformed cell lines (5-7 ...
Middle T antigen (PymT) is the principal transforming component of polyomavirus, and rapidly induces hemangiomas in neonatal ... The exact biological mechanism by which the kinases transforms cells is still not well delineated. Previous data has suggested ... ShcA and Grb2 mediate polyoma middle T antigen-induced endothelial transformation and Gab1 tyrosine phosphorylation. Siew Hwa ...
Zouzias, D., I. Prasad, and C. Basilico: State of the viral DNA in rat cells transformed by polyoma virus. II. Identification ... If early gene expression can occur, polyomavirus tumor antigens will be produced and expression of those proteins past a cell- ... 3. Polyomavirus Biology in Natural Hosts 4. Polyomavirus-Induced Tumors in Foreign Hosts 5. Polyomavirus DNA in Tumor Tissue ... 6. Association and Significance of Polyomavirus DNA with Human Tumors 7. Perspective 8. References 1. ABSTRACT Polyomaviruses ...
"Immunochemical delineation of an oncofetal antigen on normal and simian virus 40-transformed human fetal melanocytes," ... M. Shuda, H. Feng, J. K. Hyun et al., "T antigen mutations are a human tumor-specific signature for Merkel cell polyomavirus," ... M. Shuda, R. Arora, J. K. Hyun et al., "Human Merkel cell polyomavirus infection I. MCV T antigen expression in Merkel cell ... A. Mogha, A. Fautrel, N. Mouchet et al., "Merkel cell polyomavirus small T antigen mRNA level is increased following in vivo UV ...
HSECs were isolated from mouse liver using CD31-based immunomagnetic separation, immortalized with SV40 large T-antigen, and ... transformed sinusoidal endothelial cells (TSECs), maintains an endothelial phenotype as well as some HSEC-specific features. ... HSECs were isolated from mouse liver using CD31-based immunomagnetic separation, immortalized with SV40 large T-antigen, and ... HSECs were isolated from mouse liver using CD31-based immunomagnetic separation, immortalized with SV40 large T-antigen, and ...
Francès V., and Bastin, M. Gene targeting in rat embryo fibroblasts promoted by the polyomavirus large T antigen. Nucleic Acids ... Expression of the malignant phenotype in rat fibroblasts transfected with the polyomavirus transforming genes. Virol. 155 (1986 ... St-Onge, L., Bouchard, L., and Bastin, M. High-frequency recombination mediated by polyomavirus large T antigen defective in ... St-Onge, L., and Bastin, M. Amplification mediated by polyomavirus large T antigen defective in replication. J. Virol. 67 (1993 ...
It has been shown recently that a tyrosine in both the 60,000-dalton tumor antigen of polyoma virus (20) and p120 of Abelson ... were present in RSV-transformed cells, a comparison of the amounts of Tyr(P) in uninfected and RSV-transformed chicken cells ... Transforming gene product of Rous sarcoma virus phosphorylates tyrosine Message Subject (Your Name) has sent you a message from ... Tyr(P) in Normal and Transformed Cells.. Because Tyr(P) had not been detected in normal cells (28, 29) and because we now knew ...
The T antigens are the viral proteins responsible for the transformation. Infected cells carry the virus containing transformed ... The T antigens are the viral proteins responsible for the transformation. Infected cells carry the virus containing transformed ... These proteins are large T antigens and small t antigens. They are considered the viral regulatory proteins and share common N- ... JC polyomavirus Description and significance. The JC virus was first isolated from a brain in a patient with Hodgkins disease ...
... or polyomavirus middle tumor antigen," Molecular Biology of the Cell, vol. 12, no. 1, pp. 185-199, 2001. View at Google Scholar ... in two transforming DNA viruses, SV40 and polyoma virus, causes cell transformation by binding to regulatory subunits A and C ... J. Yu, A. Boyapati, and K. Rundell, "Critical role for SV40 small-t antigen in human cell transformation," Virology, vol. 290, ... This interaction is essential for ST to transform cells [84, 85]. Another study confirmed PP2A to be the target of the ...
Polyomavirus Transforming Antigens Medicine & Life Sciences * Genetically Modified Animals Medicine & Life Sciences ... ASH1 potently enhanced the tumorigenic effect of SV40 large T antigen in airway epithelium. These doubly transgenic animals ... ASH1 potently enhanced the tumorigenic effect of SV40 large T antigen in airway epithelium. These doubly transgenic animals ... ASH1 potently enhanced the tumorigenic effect of SV40 large T antigen in airway epithelium. These doubly transgenic animals ...
2 16 The polyoma virus middle-sized tumor antigen transformed mouse brain capillary endothelial cell line (bEND.3) was obtained ... Decreased antigen presentation by dendritic cells in patients with breast cancer. Clin Cancer Res 1997;3:483. ... Dendritic cell progenitor is transformed by a conditional v-rel estrogen receptor fusion protein v-RelER. Cell 1995;80:341. ... I. Defective antigen presentation in tumor-bearing hosts. Cell Immunol 1996;170:101. ...
p53 in polyoma virus transformed REF52 cells. Mor, Orna; Read, Moira; Fried, Mike // Oncogene;12/18/97, Vol. 15 Issue 25, p3113 ... Genetic variability of the small t antigen of the novel KI, WU and MC polyomaviruses. Ciccozzi, Massimo; Babakir-Mina, Muhammed ... Generation of chimeric hamster polyomavirus VP1 virus-like particles harboring three tumor-associated antigens. Aleksaitė, Eglė ... To study the genetic variability of these viruses, an evolutionary analysis of the large T antigen, small t antigen, VP1, VP2 ...
  • Phosphatidylinositol 3-kinase binding to polyoma virus middle tumor antigen mediates elevation of glucose transport by increasing translocation of the GLUT1 transporter. (semanticscholar.org)
  • Cellular transformation by Simian Virus 40 and Murine Polyoma Virus T antigens. (nih.gov)
  • Several novel cell clones (A1-A6) derived from the rat embryo fibroblasts immortalized by the polyoma virus T-antigen (LT) gene and transformed by HPV18 E6 and E7 genes were explored. (spandidos-publications.com)
  • The quantity of p53 protein in cell clones did not correlate with the level of polyoma virus large T-antigen expression. (spandidos-publications.com)
  • Polyoma middle T antigen requires cooperation from another gene to express the malignant phenotype in vivo. (usherbrooke.ca)
  • Immunoprecipitates prepared from polyoma virus-infected cells and antipolyoma tumor antiserum contain a novel activity that is capable of phosphorylating a tyrosine in the 60,000-dalton large tumor antigen of polyoma virus present in the precipitate ( 20 ). (pnas.org)
  • Here, we describe the generation of a progressive and metastatic pancreatic cancer mouse model after the somatic and sporadic delivery of avian retroviruses encoding the mouse polyoma virus middle T antigen to elastase-tv-a transgenic mice with a pancreas-specific deletion of the Trp53 tumor suppressor locus. (umassmed.edu)
  • Transgenic expression of the polyoma virus middle T antigen, under control of the mouse mammary tumor virus enhancer/promoter, was used to produce mammary tumors in the absence or presence of Cre (TβRII (fl/fl);PY and TβRII (fl/fl);PY;WC , respectively). (aacrjournals.org)
  • Large T antigens (LTA) encoded by polyoma viruses are oncoproteins, which are thought to require support of cellular heat shock protein 70 (HSP70) to exert their transforming activity. (uni-wuerzburg.de)
  • MTag is expressed early in the infectious cycle along with two other related proteins, the small tumor antigen and large tumor antigen. (wikipedia.org)
  • Strikingly, T-cell responses against the two oncogenic MCPyV proteins Large T antigen and small T antigen were exclusively present in blood of MCC patients when compared to healthy donors. (dtu.dk)
  • The genomes of adenoviruses, polyomaviruses, and papillomaviruses encode proteins that cause cells to divide. (virology.ws)
  • Cells transformed with T, E6/E7, or E1A proteins are commonly used in laboratories because they are immortal. (virology.ws)
  • The B subunit also is replaceable by viral proteins, such as the simian virus 40 small t antigen and the polyomavirus small and middle T antigens ( 13 ). (pnas.org)
  • Early in infection, the early proteins large tumour antigen (LT-ag) and small tumour antigen (st-ag) are expressed [ 1 ]. (hindawi.com)
  • The early regions of some polyomaviruses possess additional putative open reading frames and encode other early proteins due to translation of alternatively spliced transcripts [ 4 ]. (hindawi.com)
  • The early transcription unit extends from the origin to half way around the circular genome and encodes alternatively spliced transforming proteins. (kenyon.edu)
  • 7) These proteins are large T antigens and small t antigens. (kenyon.edu)
  • One major area of study has been on cells transformed by viruses that show altered growth properties and specify new viral and cellular proteins. (adlibris.com)
  • We have now begun to focus upon JCV's fifth tumor protein, small t antigen (tAg), and recent data indicate tAg contributes to viral DNA replication and binds critical cellular proteins, including PP2A, p107 and p130. (psu.edu)
  • The middle tumor antigen (also called the middle T-antigen and abbreviated MTag or MT) is a protein encoded in the genomes of some polyomaviruses, which are small double-stranded DNA viruses. (wikipedia.org)
  • The genes for the small tumor antigen (STag), middle tumor antigen (MTag), and large tumor antigen (LTag) are encoded in the "early region" of the polyomavirus genome, so named because this region of the genome is expressed early in the infectious process. (wikipedia.org)
  • A somewhat more common tumor antigen variant, an overprinted gene encoding a protein called ALTO, may be evolutionarily related to MTag. (wikipedia.org)
  • Here we identify pp70 S6 kinase (pp70S6K) as a target for signal transduction events leading from polyomavirus middle tumor antigen (mT). Two partially transforming virus mutants altered in different mT signalling pathways have been studied to elucidate the pathway leading to S6 phosphorylation. (semanticscholar.org)
  • Association of Polyomavirus middle tumor antigen with phospholipase C-gamma 1. (semanticscholar.org)
  • As an endogenous tumor antigen, the lymphocytic choriomeningitis virus (LCMV) glycoprotein (GP) was introduced also under the control of the RIP. (nih.gov)
  • Subsequent adoptive transfer of virus activated spleen cells into RIP(GP x Tag2) mice further prolonged survival (168 +/- 11 d), demonstrating continued expression of the LCMV-GP tumor antigen and MHC class I. The data show that the tumor did not spontaneously induce or maintain an activated CTL response, revealing a profound lack of immunogenicity in vivo. (nih.gov)
  • Infection of mouse fibroblasts by wild-type polyomavirus results in increased phosphorylation of ribosomal protein S6 (D.A. Talmage, J. Blenis, and T.L. Benjamin, Mol. (semanticscholar.org)
  • Fluorescently labeled murine mammary carcinoma cells, isolated from either MMTV-PyVmT transforming growth factor-beta receptor II knockout (TβRII KO) or TβRII fl/fl control mice, were combined with mammary fibroblasts and xenografted onto the chicken embryo chorioallantoic membrane. (biomedcentral.com)
  • Constitutive activation of Stat3 in fibroblasts transformed by diverse oncoproteins and in breast carcinoma cells -- Garcia et al. (aacrjournals.org)
  • We did not detect significant activation of Stat1, Stat5, or Stat6 in fibroblasts transformed by the viral oncoproteins investigated. (aacrjournals.org)
  • Furthermore, they produced new transformed lines by introducing genes encoding E6, E7, E1A, or T into normal mouse embryonic fibroblasts. (virology.ws)
  • Merkel cell carcinoma (MCC) is a highly aggressive skin cancer associated with Merkel cell polyomavirus (MCPyV). (dtu.dk)
  • Inhibition of Growth and Metastasis of Mouse Mammary Carcinoma by Selective Inhibitor of Transforming Growth Factor-{beta} Type I Receptor Kinase In vivo. (aacrjournals.org)
  • These include HTLV type 1 (lymphomas, leukaemias), Epstein-Barr virus (nasopharyngeal carcinoma and Burkitt's lymphoma), human papillomaviruses (cervical cancer), hepatitis B and C virus infections (liver cancer), HIV (immunosuppression leads to the development of cancers associated with KSHV and EBV) and Merkel cell polyomavirus (Merkel cell carcinoma of the skin). (schoolbag.info)
  • The TWiV team speaks with Patrick Moore about his discovery, with Yuan Chang, of two human tumor viruses, Kaposi's sarcoma herpesvirus and Merkel cell polyomavirus. (virology.ws)
  • The use of advanced high-throughput sequencing and improved rolling circle amplification techniques have identified the novel human polyomaviruses KI, WU, Merkel cell polyomavirus, HPyV6, HPyV7, trichodysplasia spinulosa-associated polyomavirus, and HPyV9. (hindawi.com)
  • Lymphotropic polyomavirus (LPV) and the recent described human PyV KI, WU, Merkel cell polyomavirus (MCPyV), trichodysplasia spinulosa-associated PyV (TSPyV), HPyV6, HPyV7, and HPyV9 all lack an open reading frame (ORF) corresponding to VP4, while BKV and JCV contain a putative VP4 ORF but the expression has not yet been confirmed (Table 1 ). (hindawi.com)
  • Merkel cell polyomavirus (MCPyV) is prevalent in the general population, integrates into most Merkel cell carcinomas (MCC), and encodes oncoproteins required for MCC tumor growth. (aacrjournals.org)
  • Current evidence suggests that the recently discovered Merkel cell polyomavirus (MPCyV) is causally associated with most MCCs. (aacrjournals.org)
  • In 2008, the Merkel cell polyomavirus (MCPyV) was discovered and found to be integrated into the host genome in approximately 80% of MCC tumors ( 2 ). (aacrjournals.org)
  • Merkel cell polyomavirus (MCPyV) is recognised as the causative factor in the majority of MCC cases. (hud.ac.uk)
  • Tgfbr2 MGKO mice were mated to the MMTV-polyomavirus middle T antigen (PyVmT) transgenic mouse model of metastatic breast cancer. (aacrjournals.org)
  • On episode #214 of the science show This Week in Virology , Vincent, Alan, and Kathy discuss how coagulation factor X binding to adenovirus activates the innate immune system, and a novel polyomavirus associated with brain tumors in raccoons. (virology.ws)
  • Self antigens expressed by solid tumors Do not efficiently stimulate naive or activated T cells: implications for immunotherapy. (nih.gov)
  • The simian virus 40 T antigen (Tag) expressed under the control of the rat insulin promoter (RIP) induced pancreatic beta-cell tumors producing insulin, causing progressive hypoglycemia. (nih.gov)
  • This article briefly reviews the biology of polyomaviruses and explores issues pertaining to the significance of association of polyomaviruses with human tumors. (bioscience.org)
  • The MCPyV epitopes in this report provide tools (i) to isolate both antigen- and tumor-specific T lymphocytes from blood and tumors of MCC patients, (ii) to characterize immune evasion mechanisms, (iii) to develop tumor-specific therapies such as peptide vaccines or adoptive immunotherapy, and (iv) to track T-cell responses during tumor progression or clinical trials. (aacrjournals.org)
  • Although different human tumor viruses express different viral oncogenes and induce different tumors, their oncoproteins often target similar sets of cellular tumor suppressors or signal pathways to immortalize and/or transform infected cells. (ijbs.com)
  • The other six polyomaviruses that are recognized by the ICTV include budgerigar fledgling disease virus (BFDV), bovine polyomavirus (BPyV), another murine polyomavirus [Kilham virus (KV)], baboon polyomavirus 2 (PPV-2), rabbit kidney vacuolating virus (RKV), and simian virus agent 12 (SA12). (bioscience.org)
  • Polymerase chain reaction and immunofluorescence were used to demonstrate messenger RNA and protein, respectively, for the Simian virus 40 large T antigen in the transfected cells. (elsevier.com)
  • Transfected cells, but not control cells, expressed messenger RNA coding for the Simian virus 40 large T antigen. (elsevier.com)
  • Similarly, immunofluorescent staining with monoclonal antibodies demonstrated that the Simian virus 40 large T antigen protein was present in the nucleus of the transfected cells. (elsevier.com)
  • In culture, the life of human corneal endothelial cells transfected with a plasmid vector coding for the Simian virus 40 large T antigen is extended. (elsevier.com)
  • The resulting cell line, transformed sinusoidal endothelial cells (TSECs), maintains an endothelial phenotype as well as some HSEC-specific features. (elsevier.com)
  • These results demonstrate that transformed β-cells can maintain a highly differentiated phenotype during prolonged propagation in culture, which has implications for the development of continuous β-cell lines for transplantation therapy of diabetes. (elsevier.com)
  • The expression of polyomavirus large T antigen in stably transfected C2 myoblast cells inhibits terminal differentiation without inducing a transformed phenotype. (elsevier.com)
  • Antigens, Polyomavirus Transforming" is a descriptor in the National Library of Medicine's controlled vocabulary thesaurus, MeSH (Medical Subject Headings) . (uchicago.edu)
  • Until recently, these were the only two polyomaviruses known to encode MTag, but in 2015 the genome sequence of a rat polyomavirus was reported to contain MTag as well. (wikipedia.org)
  • Initiation of replication of the human hepatitis delta virus genome from cloned DNA: role of delta antigen. (asm.org)
  • Mlt mutation in the polyomavirus genome impairing a function of the middle T protein. (usherbrooke.ca)
  • Polyomaviruses are a family of small, nonenveloped viruses with a circular double-stranded DNA genome of ~ 5,000 base pairs protected by an icosahedral protein structure. (hindawi.com)
  • Recently, three novel human polyomaviruses were discovered: KIPyV, WUPyV and MCPyV. (ebscohost.com)
  • However, in MCC patients, MCPyV acquires oncogenic potential via rare integration and T-antigen (T-Ag) truncation mutations ( 5, 6 ). (aacrjournals.org)
  • The MCPyV small tumour antigen (ST) is considered to be the main viral transforming factor, however potential mechanisms linking ST expression to the highly metastatic nature of MCC are yet to be fully elucidated. (hud.ac.uk)
  • Polyomavirus antigens which cause infection and cellular transformation. (uchicago.edu)
  • Small T antigen is necessary for the completion of the productive infection cycle. (uchicago.edu)
  • However, evidence of MTag encoding and expression has also recently been reported in at least one virus of unrelated lineage, the trichodysplasia spinulosa polyomavirus, which is a normally asymptomatic infection in humans that sometimes causes the rare disease trichodysplasia spinulosa in immunocompromised individuals. (wikipedia.org)
  • The human trichodysplasia spinulosa-associated polyomavirus (TSPyV) is distinguished among polyomaviruses for combining productive infection with cell-transforming properties. (sigmaaldrich.com)
  • Prior human polyomavirus and papillomavirus infection and incident lung cancer: a nested case-control study. (harvard.edu)
  • Global Analysis of Mouse Polyomavirus Infection Reveals Dynamic Regulation of Viral and Host Gene Expression and Promiscuous Viral RNA Editing. (harvard.edu)
  • The polyomavirus tumor (T) antigens play crucial roles in viral replication, transcription, and cellular transformation. (sigmaaldrich.com)
  • The virus cellular histones are transcribed by host RNA polymerase II into early mRNAs which are translated into the early antigen protein. (kenyon.edu)
  • This in turn suggests that RSV transforms by producing abnormally high levels of a protein very similar to a normal cellular protein kinase. (pnas.org)
  • Since its discovery in the 1950s, studies on the polyomavirus middle T antigen (PyV mT) have been essential in understanding cellular signalling and tumourigenesis. (biomedcentral.com)
  • Transforming growth factor-β (TGF-β) isoforms are growth factors that function physiologically to regulate development, cellular proliferation, and immune responses. (aacrjournals.org)
  • pp60c-src, the cellular homolog of the Rous sarcoma virus transforming protein, does not completely transform cells even when present at high levels, but has been shown to be involved in polyomavirus-induced transformation when activated by polyomavirus middle T (pmt)-antigen binding. (asm.org)
  • Except for T-antigen, virus replication depends on the cellular enzymatic machinery and so the description of viral macromolecular synthesis has provided valuable insights into the cellular biosynthetic pathways. (adlibris.com)
  • A mouse polyomavirus-encoded microRNA targets the cellular apoptosis pathway through Smad2 inhibition. (harvard.edu)
  • Heterogeneous group of immunocompetent cells that mediates the cellular immune response by processing and presenting antigens to the T-cell receptor. (slicksurface.com)
  • Substantial support for this idea comes from the observation that temperature-sensitive mutations that render the virus unable to transform also decrease the protein kinase activity induced at the nonpermissive temperature and cause this activity to be extremely labile after lysis of infected cells ( 2 , 4 , 6 ⇓ ⇓ - 9 ). (pnas.org)
  • Mutations within the putative ATP-binding site of P130gag-fps at lysine-950 destroy both its kinase and transforming activities, supporting the idea that the tyrosine kinase activity intrinsic to P130gag-fps is essential for its transforming function. (ubc.ca)
  • In MTag-containing polyomaviruses, the early region contains at least three genes encoding STag, MTag, and LTag, and is transcribed as a single messenger RNA processed by alternative splicing. (wikipedia.org)
  • To study the genetic variability of these viruses, an evolutionary analysis of the large T antigen, small t antigen, VP1, VP2 and VP3 genes was carried out. (ebscohost.com)
  • Of the genes analyzed, only the small t antigen of. (ebscohost.com)
  • T-antigens that are the hallmark of transformed cells are also expressed in cells that are lytically infected and are required for viral DNA replication and also function to alter rates of transcription of the early and late viral genes. (adlibris.com)
  • As a result of our findings, this study provides valuable new insights into polyomavirus T gene use and expression. (sigmaaldrich.com)
  • In the present work, we report on the lifting of this inhibition by a mutation that prevents polyomavirus large T antigen from binding to the product of the retinoblastoma susceptibility gene (p105 RB). (elsevier.com)
  • Characterization of a normal avian cell protein related to the avian sarcoma virus transforming gene product. (harvard.edu)
  • A normal cell protein similar in structure and function to the avian sarcoma virus transforming gene product. (harvard.edu)
  • The src gene product of transformed and morphologically reverted ASV-infected mammalian cells. (harvard.edu)
  • MTag is also well known from the hamster polyomavirus, although the sequence C-terminal to the J domain has little homology between the mouse and hamster viruses. (wikipedia.org)
  • Polyomaviruses are small DNA viruses that typically establish persistent but inapparent infections of their natural hosts, although cytolytic disease may develop if the host becomes immunocompromised. (bioscience.org)
  • Polyomaviruses are nonenveloped icosahedral DNA viruses that are relatively small, having capsids with a diameter of about 45 nm. (bioscience.org)
  • Currently, there are twelve members of the genus Polyomavirus recognized by the International Committee on Taxonomy of Viruses (ICTV). (bioscience.org)
  • This observation is consistent with expectations that it evolved uniquely in the rodent lineage of the polyomavirus family. (wikipedia.org)
  • These include the ability to immortalize primary cells, transform rodent cells in culture, and induce S phase in quiescent cells (reviewed in reference 41 ). (asm.org)
  • Summarizing, TSPyV exhibits an expression pattern characterized by both MT and ALTO expression, combining features of rodent and human polyomaviruses. (sigmaaldrich.com)
  • So far, none of the human polyomaviruses was shown to express MT, which is considered the most important viral oncoprotein of rodent polyomaviruses. (sigmaaldrich.com)
  • In this study, we investigated STAT activation in a panel of rodent fibroblast cell lines stably transformed by diverse viral oncoproteins. (aacrjournals.org)
  • While PY also encodes LT and ST, the unique middle T (MT) generates most of the transforming activity. (nih.gov)
  • Among the determined viral microRNA precursors, EBV encodes 25 from two major clusters (BART and BHRF1), KSHV encodes 12 from a latent region, human polyomavirus MCV produce only one microRNA from the late region antisense to early transcripts, but HPVs appears to produce no viral microRNAs. (ijbs.com)
  • The large T antigen is necessary for the initiation of viral DNA synthesis, repression of transcription of the early region and is responsible in conjunction with the middle T antigen for the transformation of primary cells. (uchicago.edu)
  • Transformation and tumorigenic properties of a mutant polyomavirus containing a middle T antigen defective in Shc binding. (semanticscholar.org)
  • Enhancement of transformation was not observed with polyomavirus small t (pst) antigen. (asm.org)
  • Transformation studies have focused on the tumor (T) antigens that are specified by the virus and are required to initiate and to maintain the transformed state. (adlibris.com)
  • Transformation by Polyomavirus Middle T Antigen Involves a Unique Bimodal Interaction with the Hippo Effector YAP. (harvard.edu)
  • Transformation by the N‐terminal region of a large T antigen is a result, at least in part, of the release of E2F caused by the inactivation of Rb. (embopress.org)
  • Identification of a transformation-specific antigen induced by an avian sarcoma virus. (harvard.edu)
  • Peptide analysis of the transformation-specific antigen from avian sarcoma virus-transformed cells. (harvard.edu)
  • The circular genomes of all polyomaviruses are superficially arranged in a similar manner, and three general regions can be identified based on function. (bioscience.org)
  • Polyomavirus and Papillomavirus . (bioscience.org)
  • An example is the famous HeLa cell line, transformed by human papillomavirus type 18 (which originally infected Henrietta Lacks and caused the cervical tumor that killed her). (virology.ws)
  • Expression of the viral E6 and E7 oncogenes in papillomavirus, E1A and E1B oncogenes in adenovirus, large T and small t antigen in polyomavirus, and Tax oncogene in HTLV-1 are regulated by alternative RNA splicing. (ijbs.com)
  • Another commonly used transformed cell line is 293 (human embryonic kidney cells transformed by adenovirus E1A). (virology.ws)
  • Morphological revertants of an avian sarcoma virus-transformed mammalian cell line exhibit tumorigenicity and contain pp60src. (harvard.edu)
  • First, chicken cells transformed by Rous sarcoma virus contain as much as 8-fold more phosphotyrosine than do uninfected cells. (pnas.org)
  • Natural biology of polyomavirus middle T antigen. (semanticscholar.org)
  • Evidence of a role for phosphatidylinositol 3-kinase activation in the blocking of apoptosis by polyomavirus middle T antigen. (semanticscholar.org)
  • Characterization of T Antigens, Including Middle T and Alternative T, Expressed by the Human Polyomavirus Associated with Trichodysplasia Spinulosa. (sigmaaldrich.com)
  • Sequencing of T antigen-encoded reverse transcription-PCR (RT-PCR) products revealed three splice donor and acceptor sites creating six mRNA splice products that potentially encode the antigens small T (ST), middle T (MT), large T (LT), tiny T, 21kT, and alternative T (ALTO). (sigmaaldrich.com)
  • In the research presented here, we further substantiate this unique position by indicating expression of both middle T antigen (MT) and alternative T antigen (ALTO) in TSPyV. (sigmaaldrich.com)
  • We sought to engineer a novel mouse model of polyomavirus middle T antigen (PyV mT)-mediated mammary tumourigenesis in which inducible expression of this well-characterized viral oncoprotein is coupled to Cre recombinase (TetO-PyV mT-IRES-Cre recombinase or MIC). (biomedcentral.com)
  • Further characterisation of the complex containing middle T antigen and pp60. (elsevier.com)
  • Tryptic phosphopeptide maps indicate that p85 from polyomavirus middle T-transformed cells is phosphorylated in vivo at three sites phosphorylated in vitro by the associated serine kinase. (asm.org)
  • This suggests that the association of protein phosphatase 2A with middle T antigen may function to activate PtdIns 3-kinase. (asm.org)
  • Furthermore, we correlate the cell cycle alteration induced by polyomavirus large T antigen expression with the inability of the cells to undergo terminal differentiation. (elsevier.com)
  • Both the N‐terminal J domain and the LxCxE motif of large T antigen are required for inactivation of Rb. (embopress.org)
  • The two central helices and a connecting loop in large T antigen have structural similarities with the J domains of the molecular chaperones DnaJ and HDJ‐1, suggesting that large T antigen may use a chaperone mechanism for its biological function. (embopress.org)
  • However, there are significant differences between large T antigen and the molecular chaperones in other regions and these differences are likely to provide the specificity needed for large T antigen to inactivate Rb. (embopress.org)
  • The LT K1 mutant can also be complemented for p53 override by small t antigen (st) in a manner independent of its J domain. (asm.org)
  • Genetic variability of the small t antigen of the novel KI, WU and MC polyomaviruses. (ebscohost.com)
  • We previously have shown that adenovirus type 5 E4orf4 protein associates with protein phosphatase 2A (PP2A) and induces apoptosis in transformed cells in a p53-independent manner. (pnas.org)
  • Recently, we and others have shown that E4orf4 protein induces p53-independent apoptosis in several transformed cell lines ( 5 - 7 ). (pnas.org)
  • The article presents the author's comments on researcher A. M. Gaynor's article entitled "Identification of a Novel Polyomavirus From Patients With Acute Respiratory Tract Infections. (ebscohost.com)
  • According to the author, the findings of the study suggests that this novel polyomavirus has a role in. (ebscohost.com)
  • T-antigen expression in 24 of 31 skin fibroblast cell lines from members of Family G was found to be significantly elevated compared with a healthy control population. (elsevier.com)
  • The T expression pattern of the trichodysplasia spinulosa-associated polyomavirus (TSPyV) has not been established yet, hampering further study of its pathogenic mechanisms and taxonomic relationship. (sigmaaldrich.com)
  • Interferon gamma (IFN-gamma) induces expression of MHC class II antigen in a time course identical to that of normal endothelial cells. (atcc.org)
  • PyV mT can readily transform cells in vitro and in vivo by stimulating key pro-tumourigenic signalling axes. (biomedcentral.com)
  • At nonpermissive temperature, HT4 cells differentiated with neuronal morphology, expressed neuronal antigens, synthesized nerve growth factor (NGF) mRNA, and secreted biologically active NGF in vitro. (elsevier.com)
  • One of the major limitations of highly active antiretroviral therapy is its inability to inhibit the replication of polyomavirus JC (JCV), the etiologic agent of progressive multifocal leukoencephalopathy (PML), an acquired immunodeficiency syndromeâ€"defining illness. (ebscohost.com)
  • the construction and phenotypic analysis of hybrid polyomaviruses and the use of site-directed mutagenesis to alter cis-acting replication signals and specific functional domains of T protein. (psu.edu)
  • Most polyomaviruses have the ability to induce tumor formation when introduced into certain foreign hosts and are considered oncoviruses. (bioscience.org)
  • The LT-ag of different polyomaviruses can transform cells from different species and induce tumours in animal models and is therefore implicated in the tumourigenic properties of polyomaviruses (see further). (hindawi.com)
  • Transforming growth factor beta (TGF-β) has a dual role during tumor progression, initially as a suppressor and then as a promoter. (biomedcentral.com)
  • The transforming growth factor β (TGF-β) ligands TGF-β1, TGF-β2, and TGF-β3 are potent regulators of cell behavior, and their activity can significantly regulate processes involved in tumor initiation, progression, and metastasis ( 1 - 4 ). (aacrjournals.org)
  • Transforming growth factor (TGF)-beta1 and TGF-beta3 are normally expressed at high levels in the mammary gland during quiescence and at all stages of development, except lactation. (aacrjournals.org)
  • At harvest, cell number, alkaline phosphatase-specific activity, and production of osteocalcin, transforming growth factor β1 (TGF- β1) and prostaglandin E 2 (PGE 2 ) were measured. (elsevier.com)
  • Transfected cells were shown to produce messenger RNA coding for epidermal growth factor, epidermal growth factor receptor, basic fibroblast growth factor, fibroblast growth factor receptor-1, interleukin-1 alpha, the interleukin-1 receptor, transforming growth factor beta-1, and the glucocorticoid receptor. (elsevier.com)