A system of cisternae in the CYTOPLASM of many cells. In places the endoplasmic reticulum is continuous with the plasma membrane (CELL MEMBRANE) or outer membrane of the nuclear envelope. If the outer surfaces of the endoplasmic reticulum membranes are coated with ribosomes, the endoplasmic reticulum is said to be rough-surfaced (ENDOPLASMIC RETICULUM, ROUGH); otherwise it is said to be smooth-surfaced (ENDOPLASMIC RETICULUM, SMOOTH). (King & Stansfield, A Dictionary of Genetics, 4th ed)
Various physiological or molecular disturbances that impair ENDOPLASMIC RETICULUM function. It triggers many responses, including UNFOLDED PROTEIN RESPONSE, which may lead to APOPTOSIS; and AUTOPHAGY.
A type of endoplasmic reticulum (ER) where polyribosomes are present on the cytoplasmic surfaces of the ER membranes. This form of ER is prominent in cells specialized for protein secretion and its principal function is to segregate proteins destined for export or intracellular utilization.
A network of tubules and sacs in the cytoplasm of SKELETAL MUSCLE FIBERS that assist with muscle contraction and relaxation by releasing and storing calcium ions.
A type of endoplasmic reticulum lacking associated ribosomes on the membrane surface. It exhibits a wide range of specialized metabolic functions including supplying enzymes for steroid synthesis, detoxification, and glycogen breakdown. In muscle cells, smooth endoplasmic reticulum is called SARCOPLASMIC RETICULUM.
A stack of flattened vesicles that functions in posttranslational processing and sorting of proteins, receiving them from the rough ENDOPLASMIC RETICULUM and directing them to secretory vesicles, LYSOSOMES, or the CELL MEMBRANE. The movement of proteins takes place by transfer vesicles that bud off from the rough endoplasmic reticulum or Golgi apparatus and fuse with the Golgi, lysosomes or cell membrane. (From Glick, Glossary of Biochemistry and Molecular Biology, 1990)
A cellular response to environmental insults that cause disruptions in PROTEIN FOLDING and/or accumulation of defectively folded protein in the ENDOPLASMIC RETICULUM. It consists of a group of regulatory cascades that are triggered as a response to altered levels of calcium and/or the redox state of the endoplasmic reticulum. Persistent activation of the unfolded protein response leads to the induction of APOPTOSIS.
Proteins which are found in membranes including cellular and intracellular membranes. They consist of two types, peripheral and integral proteins. They include most membrane-associated enzymes, antigenic proteins, transport proteins, and drug, hormone, and lectin receptors.
The process of moving proteins from one cellular compartment (including extracellular) to another by various sorting and transport mechanisms such as gated transport, protein translocation, and vesicular transport.
A family of cellular proteins that mediate the correct assembly or disassembly of polypeptides and their associated ligands. Although they take part in the assembly process, molecular chaperones are not components of the final structures.
Calcium-transporting ATPases that catalyze the active transport of CALCIUM into the SARCOPLASMIC RETICULUM vesicles from the CYTOPLASM. They are primarily found in MUSCLE CELLS and play a role in the relaxation of MUSCLES.
An N-acetylglycosamine containing antiviral antibiotic obtained from Streptomyces lysosuperificus. It is also active against some bacteria and fungi, because it inhibits the glucosylation of proteins. Tunicamycin is used as tool in the study of microbial biosynthetic mechanisms.
A lectin found in ENDOPLASMIC RETICULUM membranes that binds to specific N-linked OLIGOSACCHARIDES found on newly synthesized proteins. It may play role in PROTEIN FOLDING or retention and degradation of misfolded proteins in the endoplasmic reticulum.
A CCAAT-enhancer binding protein that is induced by DNA DAMAGE and growth arrest. It serves as a dominant negative inhibitor of other CCAAT-enhancer binding proteins.
Cation-transporting proteins that utilize the energy of ATP hydrolysis for the transport of CALCIUM. They differ from CALCIUM CHANNELS which allow calcium to pass through a membrane without the use of energy.
Thin structures that encapsulate subcellular structures or ORGANELLES in EUKARYOTIC CELLS. They include a variety of membranes associated with the CELL NUCLEUS; the MITOCHONDRIA; the GOLGI APPARATUS; the ENDOPLASMIC RETICULUM; LYSOSOMES; PLASTIDS; and VACUOLES.
A basic element found in nearly all organized tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.
A multifunctional protein that is found primarily within membrane-bound organelles. In the ENDOPLASMIC RETICULUM it binds to specific N-linked oligosaccharides found on newly-synthesized proteins and functions as a MOLECULAR CHAPERONE that may play a role in PROTEIN FOLDING or retention and degradation of misfolded proteins. In addition calreticulin is a major storage form for CALCIUM and functions as a calcium-signaling molecule that can regulate intracellular calcium HOMEOSTASIS.
A sesquiterpene lactone found in roots of THAPSIA. It inhibits CA(2+)-TRANSPORTING ATPASE mediated uptake of CALCIUM into SARCOPLASMIC RETICULUM.
A fungal metabolite which is a macrocyclic lactone exhibiting a wide range of antibiotic activity.
Processes involved in the formation of TERTIARY PROTEIN STRUCTURE.
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.
Artifactual vesicles formed from the endoplasmic reticulum when cells are disrupted. They are isolated by differential centrifugation and are composed of three structural features: rough vesicles, smooth vesicles, and ribosomes. Numerous enzyme activities are associated with the microsomal fraction. (Glick, Glossary of Biochemistry and Molecular Biology, 1990; from Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed)
One of the BASIC-LEUCINE ZIPPER TRANSCRIPTION FACTORS that is synthesized as a membrane-bound protein in the ENDOPLASMIC RETICULUM. In response to endoplasmic reticulum stress it translocates to the GOLGI APPARATUS. It is activated by PROTEASES and then moves to the CELL NUCLEUS to regulate GENETIC TRANSCRIPTION of GENES involved in the unfolded protein response.
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.
Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.
The chemical or biochemical addition of carbohydrate or glycosyl groups to other chemicals, especially peptides or proteins. Glycosyl transferases are used in this biochemical reaction.
Established cell cultures that have the potential to propagate indefinitely.
The movement of materials (including biochemical substances and drugs) through a biological system at the cellular level. The transport can be across cell membranes and epithelial layers. It also can occur within intracellular compartments and extracellular compartments.
The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.
Proteins which are synthesized in eukaryotic organisms and bacteria in response to hyperthermia and other environmental stresses. They increase thermal tolerance and perform functions essential to cell survival under these conditions.
A long pro-domain caspase that contains a caspase recruitment domain in its pro-domain region. Caspase 12 is activated by pro-apoptotic factors that are released during cell stress and by CARD SIGNALING ADAPTOR PROTEINS. It activates APOPTOSIS by cleaving and activating EFFECTOR CASPASES.
Amino acid sequences found in transported proteins that selectively guide the distribution of the proteins to specific cellular compartments.
Any of various enzymatically catalyzed post-translational modifications of PEPTIDES or PROTEINS in the cell of origin. These modifications include carboxylation; HYDROXYLATION; ACETYLATION; PHOSPHORYLATION; METHYLATION; GLYCOSYLATION; ubiquitination; oxidation; proteolysis; and crosslinking and result in changes in molecular weight and electrophoretic motility.
TRANSPORT VESICLES formed when cell-membrane coated pits (COATED PITS, CELL-MEMBRANE) invaginate and pinch off. The outer surface of these vesicles is covered with a lattice-like network of COP (coat protein complex) proteins, either COPI or COPII. COPI coated vesicles transport backwards from the cisternae of the GOLGI APPARATUS to the rough endoplasmic reticulum (ENDOPLASMIC RETICULUM, ROUGH), while COPII coated vesicles transport forward from the rough endoplasmic reticulum to the Golgi apparatus.
Sulfur-sulfur bond isomerases that catalyze the rearrangement of disulfide bonds within proteins during folding. Specific protein disulfide-isomerase isoenzymes also occur as subunits of PROCOLLAGEN-PROLINE DIOXYGENASE.
Components of a cell produced by various separation techniques which, though they disrupt the delicate anatomy of a cell, preserve the structure and physiology of its functioning constituents for biochemical and ultrastructural analysis. (From Alberts et al., Molecular Biology of the Cell, 2d ed, p163)
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.
The unfavorable effect of environmental factors (stressors) on the physiological functions of an organism. Prolonged unresolved physiological stress can affect HOMEOSTASIS of the organism, and may lead to damaging or pathological conditions.
Signal transduction mechanisms whereby calcium mobilization (from outside the cell or from intracellular storage pools) to the cytoplasm is triggered by external stimuli. Calcium signals are often seen to propagate as waves, oscillations, spikes, sparks, or puffs. The calcium acts as an intracellular messenger by activating calcium-responsive proteins.
Intracellular fluid from the cytoplasm after removal of ORGANELLES and other insoluble cytoplasmic components.
Proteins to which calcium ions are bound. They can act as transport proteins, regulator proteins, or activator proteins. They typically contain EF HAND MOTIFS.
CELL LINES derived from the CV-1 cell line by transformation with a replication origin defective mutant of SV40 VIRUS, which codes for wild type large T antigen (ANTIGENS, POLYOMAVIRUS TRANSFORMING). They are used for transfection and cloning. (The CV-1 cell line was derived from the kidney of an adult male African green monkey (CERCOPITHECUS AETHIOPS).)
A subfamily in the family MURIDAE, comprising the hamsters. Four of the more common genera are Cricetus, CRICETULUS; MESOCRICETUS; and PHODOPUS.
Techniques to partition various components of the cell into SUBCELLULAR FRACTIONS.
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.
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.
A species of the genus SACCHAROMYCES, family Saccharomycetaceae, order Saccharomycetales, known as "baker's" or "brewer's" yeast. The dried form is used as a dietary supplement.
Intracellular receptors that bind to INOSITOL 1,4,5-TRISPHOSPHATE and play an important role in its intracellular signaling. Inositol 1,4,5-trisphosphate receptors are calcium channels that release CALCIUM in response to increased levels of inositol 1,4,5-trisphosphate in the CYTOPLASM.
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.
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.
A broad category of proteins involved in the formation, transport and dissolution of TRANSPORT VESICLES. They play a role in the intracellular transport of molecules contained within membrane vesicles. Vesicular transport proteins are distinguished from MEMBRANE TRANSPORT PROTEINS, which move molecules across membranes, by the mode in which the molecules are transported.
Proteins obtained from the species SACCHAROMYCES CEREVISIAE. The function of specific proteins from this organism are the subject of intense scientific interest and have been used to derive basic understanding of the functioning similar proteins in higher eukaryotes.
The part of a cell that contains the CYTOSOL and small structures excluding the CELL NUCLEUS; MITOCHONDRIA; and large VACUOLES. (Glick, Glossary of Biochemistry and Molecular Biology, 1990)
A partitioning within cells due to the selectively permeable membranes which enclose each of the separate parts, e.g., mitochondria, lysosomes, etc.
The first continuously cultured human malignant CELL LINE, derived from the cervical carcinoma of Henrietta Lacks. These cells are used for VIRUS CULTIVATION and antitumor drug screening assays.
Microscopy of specimens stained with fluorescent dye (usually fluorescein isothiocyanate) or of naturally fluorescent materials, which emit light when exposed to ultraviolet or blue light. Immunofluorescence microscopy utilizes antibodies that are labeled with fluorescent dye.
A degradation process whereby incorrectly folded proteins are selectively transported out of the ENDOPLASMIC RETICULUM and into the CYTOSOL. The misfolded proteins are subsequently ubiquitinated and degraded by the PROTEASOME.
The level of protein structure in which combinations of secondary protein structures (alpha helices, beta sheets, loop regions, and motifs) pack together to form folded shapes called domains. Disulfide bridges between cysteines in two different parts of the polypeptide chain along with other interactions between the chains play a role in the formation and stabilization of tertiary structure. Small proteins usually consist of only one domain but larger proteins may contain a number of domains connected by segments of polypeptide chain which lack regular secondary structure.
An activating transcription factor that regulates the expression of a variety of GENES involved in amino acid metabolism and transport. It also interacts with HTLV-I transactivator protein.
Semiautonomous, self-reproducing organelles that occur in the cytoplasm of all cells of most, but not all, eukaryotes. Each mitochondrion is surrounded by a double limiting membrane. The inner membrane is highly invaginated, and its projections are called cristae. Mitochondria are the sites of the reactions of oxidative phosphorylation, which result in the formation of ATP. They contain distinctive RIBOSOMES, transfer RNAs (RNA, TRANSFER); AMINO ACYL T RNA SYNTHETASES; and elongation and termination factors. Mitochondria depend upon genes within the nucleus of the cells in which they reside for many essential messenger RNAs (RNA, MESSENGER). Mitochondria are believed to have arisen from aerobic bacteria that established a symbiotic relationship with primitive protoeukaryotes. (King & Stansfield, A Dictionary of Genetics, 4th ed)
One of the mechanisms by which CELL DEATH occurs (compare with NECROSIS and AUTOPHAGOCYTOSIS). Apoptosis is the mechanism responsible for the physiological deletion of cells and appears to be intrinsically programmed. It is characterized by distinctive morphologic changes in the nucleus and cytoplasm, chromatin cleavage at regularly spaced sites, and the endonucleolytic cleavage of genomic DNA; (DNA FRAGMENTATION); at internucleosomal sites. This mode of cell death serves as a balance to mitosis in regulating the size of animal tissues and in mediating pathologic processes associated with tumor growth.
The rate dynamics in chemical or physical systems.
A species of CERCOPITHECUS containing three subspecies: C. tantalus, C. pygerythrus, and C. sabeus. They are found in the forests and savannah of Africa. The African green monkey (C. pygerythrus) is the natural host of SIMIAN IMMUNODEFICIENCY VIRUS and is used in AIDS research.
A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.
Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.
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 light microscopic technique in which only a small spot is illuminated and observed at a time. An image is constructed through point-by-point scanning of the field in this manner. Light sources may be conventional or laser, and fluorescence or transmitted observations are possible.
Transport proteins that carry specific substances in the blood or across cell membranes.
Conjugated protein-carbohydrate compounds including mucins, mucoid, and amyloid glycoproteins.
A dsRNA-activated cAMP-independent protein serine/threonine kinase that is induced by interferon. In the presence of dsRNA and ATP, the kinase autophosphorylates on several serine and threonine residues. The phosphorylated enzyme catalyzes the phosphorylation of the alpha subunit of EUKARYOTIC INITIATION FACTOR-2, leading to the inhibition of protein synthesis.
A large multisubunit complex that plays an important role in the degradation of most of the cytosolic and nuclear proteins in eukaryotic cells. It contains a 700-kDa catalytic sub-complex and two 700-kDa regulatory sub-complexes. The complex digests ubiquitinated proteins and protein activated via ornithine decarboxylase antizyme.
CELL LINE derived from the ovary of the Chinese hamster, Cricetulus griseus (CRICETULUS). The species is a favorite for cytogenetic studies because of its small chromosome number. The cell line has provided model systems for the study of genetic alterations in cultured mammalian cells.
Glycoproteins found on the membrane or surface of cells.
The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.
A series of sequential intracellular steps involved in the transport of proteins (such as hormones and enzymes) from the site of synthesis to outside the cell. The pathway involves membrane-bound compartments through which the newly synthesized proteins undergo POST-TRANSLATIONAL MODIFICATIONS, packaging, storage, or transportation to the PLASMA MEMBRANE for secretion.
Voltage-dependent cell membrane glycoproteins selectively permeable to calcium ions. They are categorized as L-, T-, N-, P-, Q-, and R-types based on the activation and inactivation kinetics, ion specificity, and sensitivity to drugs and toxins. The L- and T-types are present throughout the cardiovascular and central nervous systems and the N-, P-, Q-, & R-types are located in neuronal tissue.
The intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule (hormone, neurotransmitter) is mediated via the coupling of a receptor/enzyme to a second messenger system or to an ion channel. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the GAMMA-AMINOBUTYRIC ACID-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway.
A class of MOLECULAR CHAPERONES found in both prokaryotes and in several compartments of eukaryotic cells. These proteins can interact with polypeptides during a variety of assembly processes in such a way as to prevent the formation of nonfunctional structures.
The biosynthesis of PEPTIDES and PROTEINS on RIBOSOMES, directed by MESSENGER RNA, via TRANSFER RNA that is charged with standard proteinogenic AMINO ACIDS.
Identification of proteins or peptides that have been electrophoretically separated by blot transferring from the electrophoresis gel to strips of nitrocellulose paper, followed by labeling with antibody probes.
Microscopy in which the samples are first stained immunocytochemically and then examined using an electron microscope. Immunoelectron microscopy is used extensively in diagnostic virology as part of very sensitive immunoassays.
A tetrameric calcium release channel in the SARCOPLASMIC RETICULUM membrane of SMOOTH MUSCLE CELLS, acting oppositely to SARCOPLASMIC RETICULUM CALCIUM-TRANSPORTING ATPASES. It is important in skeletal and cardiac excitation-contraction coupling and studied by using RYANODINE. Abnormalities are implicated in CARDIAC ARRHYTHMIAS and MUSCULAR DISEASES.
The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.
Protein analogs and derivatives of the Aequorea victoria green fluorescent protein that emit light (FLUORESCENCE) when excited with ULTRAVIOLET RAYS. They are used in REPORTER GENES in doing GENETIC TECHNIQUES. Numerous mutants have been made to emit other colors or be sensitive to pH.
The second stomach of ruminants. It lies almost in the midline in the front of the abdomen, in contact with the liver and diaphragm and communicates freely with the RUMEN via the ruminoreticular orifice. The lining of the reticulum is raised into folds forming a honeycomb pattern over the surface. (From Concise Veterinary Dictionary, 1988)
A bile salt formed in the liver by conjugation of chenodeoxycholate with taurine, usually as the sodium salt. It acts as detergent to solubilize fats in the small intestine and is itself absorbed. It is used as a cholagogue and choleretic.
Glycoside hydrolases that catalyze the hydrolysis of alpha or beta linked MANNOSE.
Specific particles of membrane-bound organized living substances present in eukaryotic cells, such as the MITOCHONDRIA; the GOLGI APPARATUS; ENDOPLASMIC RETICULUM; LYSOSOMES; PLASTIDS; and VACUOLES.
A class of morphologically heterogeneous cytoplasmic particles in animal and plant tissues characterized by their content of hydrolytic enzymes and the structure-linked latency of these enzymes. The intracellular functions of lysosomes depend on their lytic potential. The single unit membrane of the lysosome acts as a barrier between the enzymes enclosed in the lysosome and the external substrate. The activity of the enzymes contained in lysosomes is limited or nil unless the vesicle in which they are enclosed is ruptured. Such rupture is supposed to be under metabolic (hormonal) control. (From Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed)
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.
An adenine nucleotide containing three phosphate groups esterified to the sugar moiety. In addition to its crucial roles in metabolism adenosine triphosphate is a neurotransmitter.
Closed vesicles of fragmented endoplasmic reticulum created when liver cells or tissue are disrupted by homogenization. They may be smooth or rough.
Proteins found in any species of fungus.
Eukaryotic initiation factor of protein synthesis. In higher eukaryotes the factor consists of three subunits: alpha, beta, and gamma. As initiation proceeds, eIF-2 forms a ternary complex with Met-tRNAi and GTP.
Any spaces or cavities within a cell. They may function in digestion, storage, secretion, or excretion.
A group of alicyclic hydrocarbons with the general formula R-C5H9.
Proteins prepared by recombinant DNA technology.
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.
A 700-kDa cytosolic protein complex consisting of seven equimolar subunits (alpha, beta, beta', gamma, delta, epsilon and zeta). COATOMER PROTEIN and ADP-RIBOSYLATION FACTOR 1 are principle components of COAT PROTEIN COMPLEX I and are involved in vesicle transport between the ENDOPLASMIC RETICULUM and the GOLGI APPARATUS.
The processes whereby the internal environment of an organism tends to remain balanced and stable.
Acidic protein found in SARCOPLASMIC RETICULUM that binds calcium to the extent of 700-900 nmoles/mg. It plays the role of sequestering calcium transported to the interior of the intracellular vesicle.
A methylxanthine naturally occurring in some beverages and also used as a pharmacological agent. Caffeine's most notable pharmacological effect is as a central nervous system stimulant, increasing alertness and producing agitation. It also relaxes SMOOTH MUSCLE, stimulates CARDIAC MUSCLE, stimulates DIURESIS, and appears to be useful in the treatment of some types of headache. Several cellular actions of caffeine have been observed, but it is not entirely clear how each contributes to its pharmacological profile. Among the most important are inhibition of cyclic nucleotide PHOSPHODIESTERASES, antagonism of ADENOSINE RECEPTORS, and modulation of intracellular calcium handling.
Linear POLYPEPTIDES that are synthesized on RIBOSOMES and may be further modified, crosslinked, cleaved, or assembled into complex proteins with several subunits. The specific sequence of AMINO ACIDS determines the shape the polypeptide will take, during PROTEIN FOLDING, and the function of the protein.
A subtype of caspases that contain long pro-domain regions that regulate the activation of the enzyme. The pro-domain regions contain protein-protein interaction motifs that can interact with specific signaling adaptor proteins such as DEATH DOMAIN RECEPTORS; DED SIGNALING ADAPTOR PROTEINS; and CARD SIGNALING ADAPTOR PROTEINS. Once activated, the initiator caspases can activate other caspases such as the EFFECTOR CASPASES.
The domestic dog, Canis familiaris, comprising about 400 breeds, of the carnivore family CANIDAE. They are worldwide in distribution and live in association with people. (Walker's Mammals of the World, 5th ed, p1065)
The membrane system of the CELL NUCLEUS that surrounds the nucleoplasm. It consists of two concentric membranes separated by the perinuclear space. The structures of the envelope where it opens to the cytoplasm are called the nuclear pores (NUCLEAR PORE).
Proteins which are involved in the phenomenon of light emission in living systems. Included are the "enzymatic" and "non-enzymatic" types of system with or without the presence of oxygen or co-factors.
Enzymes that catalyze the hydrolysis of N-acylhexosamine residues in N-acylhexosamides. Hexosaminidases also act on GLUCOSIDES; GALACTOSIDES; and several OLIGOSACCHARIDES.
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.
A methylpyrrole-carboxylate from RYANIA that disrupts the RYANODINE RECEPTOR CALCIUM RELEASE CHANNEL to modify CALCIUM release from SARCOPLASMIC RETICULUM resulting in alteration of MUSCLE CONTRACTION. It was previously used in INSECTICIDES. It is used experimentally in conjunction with THAPSIGARGIN and other inhibitors of CALCIUM ATPASE uptake of calcium into SARCOPLASMIC RETICULUM.
A carboxypeptidase that catalyzes the release of a C-terminal amino acid with a broad specificity. It also plays a role in the LYSOSOMES by protecting BETA-GALACTOSIDASE and NEURAMINIDASE from degradation. It was formerly classified as EC and EC
Elements of limited time intervals, contributing to particular results or situations.
Cell surface receptors that bind peptide messengers with high affinity and regulate intracellular signals which influence the behavior of cells.
A protein complex comprised of COATOMER PROTEIN and ADP RIBOSYLATION FACTOR 1. It is involved in transport of vesicles between the ENDOPLASMIC RETICULUM and the GOLGI APPARATUS.
A group of related enzymes responsible for the endohydrolysis of the di-N-acetylchitobiosyl unit in high-mannose-content glycopeptides and GLYCOPROTEINS.
Membrane proteins whose primary function is to facilitate the transport of molecules across a biological membrane. Included in this broad category are proteins involved in active transport (BIOLOGICAL TRANSPORT, ACTIVE), facilitated transport and ION CHANNELS.
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.
Intracellular messenger formed by the action of phospholipase C on phosphatidylinositol 4,5-bisphosphate, which is one of the phospholipids that make up the cell membrane. Inositol 1,4,5-trisphosphate is released into the cytoplasm where it releases calcium ions from internal stores within the cell's endoplasmic reticulum. These calcium ions stimulate the activity of B kinase or calmodulin.
A group of enzymes which catalyze the hydrolysis of ATP. The hydrolysis reaction is usually coupled with another function such as transporting Ca(2+) across a membrane. These enzymes may be dependent on Ca(2+), Mg(2+), anions, H+, or DNA.
A cell line derived from cultured tumor cells.
Chemical groups containing the covalent disulfide bonds -S-S-. The sulfur atoms can be bound to inorganic or organic moieties.
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.
A cell line generated from human embryonic kidney cells that were transformed with human adenovirus type 5.
Compounds or agents that combine with an enzyme in such a manner as to prevent the normal substrate-enzyme combination and the catalytic reaction.
A genetically related subfamily of RAB GTP-BINDING PROTEINS involved in vesicle transport between the ENDOPLASMIC RETICULUM and the GOLGI APPARATUS and through early Golgi compartments. This enzyme was formerly listed as EC
Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.
The segregation and degradation of damaged or unwanted cytoplasmic constituents by autophagic vacuoles (cytolysosomes) composed of LYSOSOMES containing cellular components in the process of digestion; it plays an important role in BIOLOGICAL METAMORPHOSIS of amphibians, in the removal of bone by osteoclasts, and in the degradation of normal cell components in nutritional deficiency states.
The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).
A class of compounds composed of repeating 5-carbon units of HEMITERPENES.
The introduction of a phosphoryl group into a compound through the formation of an ester bond between the compound and a phosphorus moiety.
Enzymes that catalyze the transfer of mannose from a nucleoside diphosphate mannose to an acceptor molecule which is frequently another carbohydrate. The group includes EC, EC, EC, and EC
An organization of cells into an organ-like structure. Organoids can be generated in culture. They are also found in certain neoplasms.
A family of enzymes that catalyze the endonucleolytic cleavage of RNA. It includes EC 3.1.26.-, EC 3.1.27.-, EC 3.1.30.-, and EC 3.1.31.-.
Compounds which inhibit the synthesis of proteins. They are usually ANTI-BACTERIAL AGENTS or toxins. Mechanism of the action of inhibition includes the interruption of peptide-chain elongation, the blocking the A site of ribosomes, the misreading of the genetic code or the prevention of the attachment of oligosaccharide side chains to glycoproteins.
The movement of materials across cell membranes and epithelial layers against an electrochemical gradient, requiring the expenditure of metabolic energy.
The parts of a macromolecule that directly participate in its specific combination with another molecule.
Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control (induction or repression) of gene action at the level of transcription or translation.
Layers of protein which surround the capsid in animal viruses with tubular nucleocapsids. The envelope consists of an inner layer of lipids and virus specified proteins also called membrane or matrix proteins. The outer layer consists of one or more types of morphological subunits called peplomers which project from the viral envelope; this layer always consists of glycoproteins.
A genus of the family Muridae consisting of eleven species. C. migratorius, the grey or Armenian hamster, and C. griseus, the Chinese hamster, are the two species used in biomedical research.
An enzyme that catalyzes the HYDROLYSIS of terminal, non-reducing alpha-D-mannose residues in alpha-D-mannosides. The enzyme plays a role in the processing of newly formed N-glycans and in degradation of mature GLYCOPROTEINS. There are multiple isoforms of alpha-mannosidase, each having its own specific cellular location and pH optimum. Defects in the lysosomal form of the enzyme results in a buildup of mannoside intermediate metabolites and the disease ALPHA-MANNOSIDOSIS.
Genetically engineered MUTAGENESIS at a specific site in the DNA molecule that introduces a base substitution, or an insertion or deletion.
A cytosolic ribonucleoprotein complex that acts to induce elongation arrest of nascent presecretory and membrane proteins until the ribosome becomes associated with the rough endoplasmic reticulum. It consists of a 7S RNA and at least six polypeptide subunits (relative molecular masses 9, 14, 19, 54, 68, and 72K).
Members of the class of compounds composed of AMINO ACIDS joined together by peptide bonds between adjacent amino acids into linear, branched or cyclical structures. OLIGOPEPTIDES are composed of approximately 2-12 amino acids. Polypeptides are composed of approximately 13 or more amino acids. PROTEINS are linear polypeptides that are normally synthesized on RIBOSOMES.
Carbohydrates consisting of between two (DISACCHARIDES) and ten MONOSACCHARIDES connected by either an alpha- or beta-glycosidic link. They are found throughout nature in both the free and bound form.
A class of enzymes that catalyze geometric or structural changes within a molecule to form a single product. The reactions do not involve a net change in the concentrations of compounds other than the substrate and the product.(from Dorland, 28th ed) EC 5.
Single-stranded complementary DNA synthesized from an RNA template by the action of RNA-dependent DNA polymerase. cDNA (i.e., complementary DNA, not circular DNA, not C-DNA) is used in a variety of molecular cloning experiments as well as serving as a specific hybridization probe.
Study of intracellular distribution of chemicals, reaction sites, enzymes, etc., by means of staining reactions, radioactive isotope uptake, selective metal distribution in electron microscopy, or other methods.
A family of heat-shock proteins that contain a 70 amino-acid consensus sequence known as the J domain. The J domain of HSP40 heat shock proteins interacts with HSP70 HEAT-SHOCK PROTEINS. HSP40 heat-shock proteins play a role in regulating the ADENOSINE TRIPHOSPHATASES activity of HSP70 heat-shock proteins.
A nodular organ in the ABDOMEN that contains a mixture of ENDOCRINE GLANDS and EXOCRINE GLANDS. The small endocrine portion consists of the ISLETS OF LANGERHANS secreting a number of hormones into the blood stream. The large exocrine portion (EXOCRINE PANCREAS) is a compound acinar gland that secretes several digestive enzymes into the pancreatic ductal system that empties into the DUODENUM.
Connective tissue cells which secrete an extracellular matrix rich in collagen and other macromolecules.
Electron microscopy in which the ELECTRONS or their reaction products that pass down through the specimen are imaged below the plane of the specimen.
The aggregation of soluble ANTIGENS with ANTIBODIES, alone or with antibody binding factors such as ANTI-ANTIBODIES or STAPHYLOCOCCAL PROTEIN A, into complexes large enough to fall out of solution.
A hexose or fermentable monosaccharide and isomer of glucose from manna, the ash Fraxinus ornus and related plants. (From Grant & Hackh's Chemical Dictionary, 5th ed & Random House Unabridged Dictionary, 2d ed)
Commonly observed structural components of proteins formed by simple combinations of adjacent secondary structures. A commonly observed structure may be composed of a CONSERVED SEQUENCE which can be represented by a CONSENSUS SEQUENCE.
A reagent commonly used in biochemical studies as a protective agent to prevent the oxidation of SH (thiol) groups and for reducing disulphides to dithiols.
An enzyme that catalyzes the conversion of D-glucose 6-phosphate and water to D-glucose and orthophosphate. EC
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)
Plasma glycoprotein member of the serpin superfamily which inhibits TRYPSIN; NEUTROPHIL ELASTASE; and other PROTEOLYTIC ENZYMES.
Enzymes that catalyze the exohydrolysis of 1,4-alpha-glucosidic linkages with release of alpha-glucose. Deficiency of alpha-1,4-glucosidase may cause GLYCOGEN STORAGE DISEASE TYPE II.
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.
Cell surface receptors for AUTOCRINE MOTILITY FACTOR, which is the secreted form of GLUCOSE-6-PHOSPHATE ISOMERASE. The receptor has an unusual composition in that it shares some structural similarities with G-PROTEIN-COUPLED RECEPTORS and functions as an ubiquitin protein ligase when internalized.
Histochemical localization of immunoreactive substances using labeled antibodies as reagents.
The termination of the cell's ability to carry out vital functions such as metabolism, growth, reproduction, responsiveness, and adaptability.
Separation of particles according to density by employing a gradient of varying densities. At equilibrium each particle settles in the gradient at a point equal to its density. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Short sequences (generally about 10 base pairs) of DNA that are complementary to sequences of messenger RNA and allow reverse transcriptases to start copying the adjacent sequences of mRNA. Primers are used extensively in genetic and molecular biology techniques.
Multicomponent ribonucleoprotein structures found in the CYTOPLASM of all cells, and in MITOCHONDRIA, and PLASTIDS. They function in PROTEIN BIOSYNTHESIS via GENETIC TRANSLATION.
A group of acylated oligopeptides produced by Actinomycetes that function as protease inhibitors. They have been known to inhibit to varying degrees trypsin, plasmin, KALLIKREINS, papain and the cathepsins.
ENDOPEPTIDASES which have a cysteine involved in the catalytic process. This group of enzymes is inactivated by CYSTEINE PROTEINASE INHIBITORS such as CYSTATINS and SULFHYDRYL REAGENTS.
Endogenous substances, usually proteins, which are effective in the initiation, stimulation, or termination of the genetic transcription process.
A highly conserved 76-amino acid peptide universally found in eukaryotic cells that functions as a marker for intracellular PROTEIN TRANSPORT and degradation. Ubiquitin becomes activated through a series of complicated steps and forms an isopeptide bond to lysine residues of specific proteins within the cell. These "ubiquitinated" proteins can be recognized and degraded by proteosomes or be transported to specific compartments within the cell.
A disturbance in the prooxidant-antioxidant balance in favor of the former, leading to potential damage. Indicators of oxidative stress include damaged DNA bases, protein oxidation products, and lipid peroxidation products (Sies, Oxidative Stress, 1991, pxv-xvi).
The arrangement of two or more amino acid or base sequences from an organism or organisms in such a way as to align areas of the sequences sharing common properties. The degree of relatedness or homology between the sequences is predicted computationally or statistically based on weights assigned to the elements aligned between the sequences. This in turn can serve as a potential indicator of the genetic relatedness between the organisms.
Thin layers of tissue which cover parts of the body, separate adjacent cavities, or connect adjacent structures.
The phenotypic manifestation of a gene or genes by the processes of GENETIC TRANSCRIPTION and GENETIC TRANSLATION.
Small double-stranded, non-protein coding RNAs (21-31 nucleotides) involved in GENE SILENCING functions, especially RNA INTERFERENCE (RNAi). Endogenously, siRNAs are generated from dsRNAs (RNA, DOUBLE-STRANDED) by the same ribonuclease, Dicer, that generates miRNAs (MICRORNAS). The perfect match of the siRNAs' antisense strand to their target RNAs mediates RNAi by siRNA-guided RNA cleavage. siRNAs fall into different classes including trans-acting siRNA (tasiRNA), repeat-associated RNA (rasiRNA), small-scan RNA (scnRNA), and Piwi protein-interacting RNA (piRNA) and have different specific gene silencing functions.
Condensed areas of cellular material that may be bounded by a membrane.
A glycoside hydrolase found primarily in PLANTS and YEASTS. It has specificity for beta-D-fructofuranosides such as SUCROSE.
Physiological processes in biosynthesis (anabolism) and degradation (catabolism) of LIPIDS.
A chelating agent relatively more specific for calcium and less toxic than EDETIC ACID.
A class of monomeric, low molecular weight (20-25 kDa) GTP-binding proteins that regulate a variety of intracellular processes. The GTP bound form of the protein is active and limited by its inherent GTPase activity, which is controlled by an array of GTPase activators, GDP dissociation inhibitors, and guanine nucleotide exchange factors. This enzyme was formerly listed as EC
Strains of mice in which certain GENES of their GENOMES have been disrupted, or "knocked-out". To produce knockouts, using RECOMBINANT DNA technology, the normal DNA sequence of the gene being studied is altered to prevent synthesis of a normal gene product. Cloned cells in which this DNA alteration is successful are then injected into mouse EMBRYOS to produce chimeric mice. The chimeric mice are then bred to yield a strain in which all the cells of the mouse contain the disrupted gene. Knockout mice are used as EXPERIMENTAL ANIMAL MODELS for diseases (DISEASE MODELS, ANIMAL) and to clarify the functions of the genes.
Contractile tissue that produces movement in animals.
The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.
Compounds containing carbohydrate or glycosyl groups linked to phosphatidylinositols. They anchor GPI-LINKED PROTEINS or polysaccharides to cell membranes.
Different forms of a protein that may be produced from different GENES, or from the same gene by ALTERNATIVE SPLICING.
Intracellular receptors that can be found in the cytoplasm or in the nucleus. They bind to extracellular signaling molecules that migrate through or are transported across the CELL MEMBRANE. Many members of this class of receptors occur in the cytoplasm and are transported to the CELL NUCLEUS upon ligand-binding where they signal via DNA-binding and transcription regulation. Also included in this category are receptors found on INTRACELLULAR MEMBRANES that act via mechanisms similar to CELL SURFACE RECEPTORS.
A gene silencing phenomenon whereby specific dsRNAs (RNA, DOUBLE-STRANDED) trigger the degradation of homologous mRNA (RNA, MESSENGER). The specific dsRNAs are processed into SMALL INTERFERING RNA (siRNA) which serves as a guide for cleavage of the homologous mRNA in the RNA-INDUCED SILENCING COMPLEX. DNA METHYLATION may also be triggered during this process.
Complexes of RNA-binding proteins with ribonucleic acids (RNA).
A generic term for any circumscribed mass of foreign (e.g., lead or viruses) or metabolically inactive materials (e.g., ceroid or MALLORY BODIES), within the cytoplasm or nucleus of a cell. Inclusion bodies are in cells infected with certain filtrable viruses, observed especially in nerve, epithelial, or endothelial cells. (Stedman, 25th ed)
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.
The muscle tissue of the HEART. It is composed of striated, involuntary muscle cells (MYOCYTES, CARDIAC) connected to form the contractile pump to generate blood flow.
The sum of the weight of all the atoms in a molecule.
An amidohydrolase that removes intact asparagine-linked oligosaccharide chains from glycoproteins. It requires the presence of more than two amino-acid residues in the substrate for activity. This enzyme was previously listed as EC
A plant genus of the family SOLANACEAE. Members contain NICOTINE and other biologically active chemicals; its dried leaves are used for SMOKING.
The span of viability of a cell characterized by the capacity to perform certain functions such as metabolism, growth, reproduction, some form of responsiveness, and adaptability.

Structural and functional changes in acute liver injury. (1/12813)

Carbon tetrachloride produces liver cell injury in a variety of animal species. The first structurally recognizable changes occur in the endoplasmic reticulum, with alteration in ribosome-membrane interactions. Later there is an increase in intracellular fat, and the formation of tangled nets of the ergastoplasm. At no time are there changes in mitochondria or single membrane limited bodies in cells with intact plasmalemma, although a relative increase in cell sap may appear. In dead cells (those with plasmalemma discontinuties) crystalline deposits of calcium phosphatase may be noted. Functional changes are related to the endoplasmic reticulum and the plasma membrane. An early decrease in protein synthesis takes place; an accumulation of neutral lipid is related to this change. Later alterations in the ergastoplasmic functions (e.g., mixed function oxidation) occurs. Carbon tetrachloride is not the active agent; rather, a product of its metabolism, probably the CC1, free radical, is. The mechanisms of injury include macromolecular adduction and peroxide propagation. A third possibility includes a cascade effect with the production of secondary and tertiary products, also toxic in nature, with the ability to produce more widespread damage to intracellular structures.  (+info)

The Saccharomyces cerevisiae CWH8 gene is required for full levels of dolichol-linked oligosaccharides in the endoplasmic reticulum and for efficient N-glycosylation. (2/12813)

The Saccharomyces cerevisiae mutant cwh8 was previously found to have an anomalous cell wall. Here we show that the cwh8 mutant has an N -glycosylation defect. We found that cwh8 cells were resistant to vanadate and sensitive to hygromycin B, and produced glycoforms of invertase and carboxypeptidase Y with a reduced number of N -chains. We have cloned the CWH8 gene. We found that it was nonessential and encoded a putative transmembrane protein of 239 amino acids. Comparison of the in vitro oligosaccharyl transferase activities of membrane preparations from wild type or cwh8 Delta cells revealed no differences in enzyme kinetic properties indicating that the oligosaccharyl transferase complex of mutant cells was not affected. cwh8 Delta cells also produced normal dolichols and dolichol-linked oligosaccharide intermediates including the full-length form Glc3Man9GlcNAc2. The level of dolichol-linked oligosaccharides in cwh8 Delta cells was, however, reduced to about 20% of the wild type. We propose that inefficient N -glycosylation of secretory proteins in cwh8 Delta cells is caused by an insufficient supply of dolichol-linked oligosaccharide substrate.  (+info)

The role of oocyte transcription, the 5'UTR, and translation repression and derepression in Drosophila gurken mRNA and protein localization. (3/12813)

The establishment of the major body axes of the Drosophila egg and future embryo requires strict regulation of gurken mRNA and protein localization. Here, we show that grk mRNA and protein localization is dependent on synthesis of grk transcripts in the oocyte nucleus and on RNA localization elements in the 5' portion of the transcript. We also show that gurken mRNA and protein localization is dependent on region-specific translation of gurken transcripts and identify K10 as a probable negative regulator of gurken translation.  (+info)

Re-entering the translocon from the lumenal side of the endoplasmic reticulum. Studies on mutated carboxypeptidase yscY species. (4/12813)

Misfolded or unassembled secretory proteins are retained in the endoplasmic reticulum (ER) and subsequently degraded by the cytosolic ubiquitin-proteasome system. This requires their retrograde transport from the ER lumen into the cytosol, which is mediated by the Sec61 translocon. It had remained a mystery whether ER-localised soluble proteins are at all capable of re-entering the Sec61 channel de novo or whether a permanent contact of the imported protein with the translocon is a prerequisite for retrograde transport. In this study we analysed two new variants of the mutated yeast carboxypeptidase yscY, CPY*: a carboxy-terminal fusion protein of CPY* and pig liver esterase and a CPY* species carrying an additional glycosylation site at its carboxy-terminus. With these constructs it can be demonstrated that the newly synthesised CPY* chain is not retained in the translocation channel but reaches its ER lumenal side completely. Our data indicate that the Sec61 channel provides the essential pore for protein transport through the ER membrane in either direction; persistent contact with the translocon after import seems not to be required for retrograde transport.  (+info)

Cloning of the peroxiredoxin gene family in rats and characterization of the fourth member. (5/12813)

Peroxiredoxin (PRx) exhibits thioredoxin-dependent peroxidase activity and constitutes a family of proteins. Four members of genes from rat tissues were isolated by PCR using degenerated primers based on the sequences which encode a pair of highly conserved Cys-containing domains, and were then cloned to full-length cDNAs. These included two genes which have previously been isolated in rats, PRx I and PRx II, and two rat homologues of PRx III and PRx IV. We showed, for the first time, the simultaneous expression of all four genes in various rat tissues by Northern blotting. Since a discrepancy exists regarding cellular distribution, we further characterized PRx IV by expressing it in COS-1 cells. This clearly demonstrates that PRx IV is a secretory form and functions within the extracellular space.  (+info)

Characterization of elementary Ca2+ release signals in NGF-differentiated PC12 cells and hippocampal neurons. (6/12813)

Elementary Ca2+ release signals in nerve growth factor- (NGF-) differentiated PC12 cells and hippocampal neurons, functionally analogous to the "Ca2+ sparks" and "Ca2+ puffs" identified in other cell types, were characterized by confocal microscopy. They either occurred spontaneously or could be activated by caffeine and metabotropic agonists. The release events were dissimilar to the sparks and puffs described so far, as many arose from clusters of both ryanodine receptors (RyRs) and inositol 1,4,5-trisphosphate receptors (InsP3Rs). Increasing either the stimulus strength or loading of the intracellular stores enhanced the frequency of and coupling between elementary release sites and evoked global Ca2+ signals. In the PC12 cells, the elementary Ca2+ release preferentially occurred around the branch points. Spatio-temporal recruitment of such elementary release events may regulate neuronal activities.  (+info)

Lectin receptor sites on rat liver cell nuclear membranes. (7/12813)

The presence and localization of lectin receptor sites on rat liver cell nuclear and other endomembranes was studied by light and electron microscopy using fluorescein and ferritin-coupled lectin conjugates. Isolated nuclei labelled with fluorescein-conjugated Concanavalin A (Con A) or wheat germ agglutinin (WGA) often showed membrane staining, which sometimes was especially bright on small stretches of the nuclear surface. Unlabelled nuclei and nuclei with a complete ring fluorescence were also seen. The nuclear fluorescence corresponded in intensity to that seen on the surface of isolated rat liver cells. Con A-ferritin particles were seldom detected on the cytoplasmic surface of the intact nuclear envelope. However, at places where the 2 leaflets of the envelope were widely separated or where the outer nuclear membrane was partly torn away, heavy labelling was seen on the cisternal surface of both the inner and outer nuclear membranes. Labelling with Con A-ferritin was also found on the cisternal side of rough endoplasmic reticulum present in the specimens. No labelling was seen on the cytoplasmic surface of mitochondrial outer membrane. The results demonstrate the presence of binding sites for Con A and WGA in nuclei and an asymmetric localization of these sites on the cisternal side of ribosome-carrying endomembranes in rat liver cells.  (+info)

Missense mutations in SGLT1 cause glucose-galactose malabsorption by trafficking defects. (8/12813)

Glucose-galactose malabsorption (GGM) is an autosomal recessive disorder caused by defects in the Na+/glucose cotransporter (SGLT1). Neonates present with severe diarrhea while on any diet containing glucose and/or galactose [1]. This study focuses on a patient of Swiss and Dominican descent. All 15 exons of SGLT1 were screened using single stranded conformational polymorphism analyses, and aberrant PCR products were sequenced. Two missense mutations, Gly318Arg and Ala468Val, were identified. SGLT1 mutants were expressed in Xenopus laevis oocytes for radiotracer uptake, electrophysiological experiments, and Western blotting. Uptakes of [14C]alpha-methyl-d-glucoside by the mutants were 5% or less than that of wild-type. Two-electrode voltage-clamp experiments confirmed the transport defects, as no noticeable sugar-induced current could be elicited from either mutant [2]. Western blots of cell protein showed levels of each SGLT1 mutant protein comparable to that of wild-type, and that both were core-glycosylated. Presteady-state current measurements indicated an absence of SGLT1 in the plasma membrane. We suggest that the compound heterozygote missense mutations G318R and A468V lead to GGM in this patient by defective trafficking of mutant proteins from the endoplasmic reticulum to the plasma membrane.  (+info)

INF2 -FORMIN THAT POLYMERIZES AND DEPOL YMERIZES ACTIN ON ENDOPLASMIC RETICULUM A Thesis Submitted to the Faculty in partial fulfillment of the requirements for the degree of cfnifi;s ·K. Barlowe, Ph.D. Dean of Graduate Studies Doctor of Philosophy In Biochemistry by Ekta Seth Chhabra DARTMOUTH COLLEGE Hanover, New Hampshire May 23rd ,2008 Examining Committee: • u» Henry N. Higgs, PhP - - 1 Duane A. Compton, Ph.D D~ R. Madden, Ph.D Jennifer Lippincott-Schwartz, Ph.D ...
casSAR Dugability of Q96DN0 | ERP27 | Endoplasmic reticulum resident protein 27 - Also known as ERP27_HUMAN, ERP27, C12orf46. Specifically binds unfolded proteins and may recruit protein disulfide isomerase PDIA3 to unfolded substrates (PubMed:16940051, PubMed:23192347). Binds protein substrates via a hydrophobic pocket in the C-terminal domain (PubMed:16940051, PubMed:23192347). May play a role in the unfolded stress response (PubMed:23192347). Interacts with PDIA3.
Implementation of dendritic cell- (DC-) based therapies in organ transplantation can reduce dependency on nonspecific immunosuppression. Despite extensive research, mechanisms of equipped DCs inducing transplant tolerance remain incomplete. Here, we applied RNA interference technique to inhibit CD80 and CD86 expression in host bone marrow-derived DCs. This approach could specifically and effectively knock down CD80 and CD86 expression. T cells primed by these DCs inhibited allogeneic responses. Administration of recipient DCs loaded with alloantigen after CD80 and CD86 blockade prolonged cardiac allograft survival. We also found a higher percentage of apoptotic T cells in lymph tissues and grafts than that detected in control group. In addition, these T cells expressed high expression of GRP78 than controls, indicating activation of unfolded protein responses. Upregulation of CHOP expression among these cells suggested that the endoplasmic reticulum stress (ERS) response switched to a proapoptotic
Title: Mif1: A Missing Link between the Unfolded Protein Response Pathway and ER-Associated Protein Degradation?. VOLUME: 2 ISSUE: 2. Author(s):Theo van Laar, Alex J. van der Eb and Carrol Terleth. Affiliation:MGC-Department ofRadiation Genetics and Chemical Mutagenesis, Leiden University MedicalCenter, P. O. Box 9503, 2300 RA Leiden, the Netherlands. Keywords:Eukaryotic cells, ER-Associated Protein Degradation, Alzheimers disease, protein disulfide isomerase (PDI), ER-lumenal part, UPR-independent functions, multi-membrane spanning ER, RING-domain, E3 Ubiquitin Ligase, ER-stress. Abstract: Eukaryotic cells have three different mechanisms to deal with the accumulation of unfolded proteins in the endoplasmic reticulum: (1) In cells in which unfolded polypeptides accumulate, translation initiation is inhibited to prevent further accumulation of unfolded proteins. (2) Expression of proteins involved in polypeptide folding is strongly enhanced by a process called the Unfolded Protein Response (UPR). ...
ER retention refers to proteins that are retained in the endoplasmic reticulum, or ER, after folding; these are known as ER resident proteins. Their localization to the ER often depends on certain sequences of amino acids located at the N-terminus or C-terminus. The classical ER retention signal is the C-terminal KDEL sequence for lumen bound proteins and KKXX for transmembrane localization. These signals allow for retrieval from the Golgi apparatus by ER retention receptors, effectively maintaining the protein in the ER.[1] Other mechanisms for ER retention are being studied but are not as well characterized as signal retention. ...
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Fig. 4. Hrd1p/Hrd3p cross-linking to Hmg2p did not require the presence of Ubc7p or Cue1p. (a) Hrd3p cross-linking to Hmg2p in the presence of either the hrd1Δ, ubc7Δ, orcue1Δ allele. The appropriate null alleles of each gene required for Hmg2p degradation were introduced into the strain coexpressing 1myc-Hmg2p and 3HA-Hrd3p. Cross-linking assay was performed as in Fig. 1. (b) Hrd1p cross-linking to Hmg2p in the presence of either the hrd1Δ, ubc7Δ, orcue1Δ allele. The appropriate null alleles of each gene required for Hmg2p degradation were introduced into the strain coexpressing 1myc-Hmg2p and 3HA-Hrd1p, and the cross-linking assay was performed. (c) Hrd3p function was required for Hrd1p cross-linking to Hmg2p under normal Hrd1p expression levels. Cells expressing 1myc-Hmg2p and 3HA-Hrd1p from its native promoter and coexpressing either the wild-type HRD3 allele (wt), the hrd3Δ allele, or the truncated hrd3 allele (hrd3357-833 ) were subjected to the cross-linking assay. (d) Expression ...
Protein kinase R (PKR)-like endoplasmic reticulum kinase (PERK) is a type I endoplasmic reticulum transmembrane protein containing a stress-sensing domain facing the endoplasmic reticulum lumen and a cytosolic kinase domain. PERK is a major component of the unfolded protein response (UPR), which promotes the adaptation of cells to various forms of stress. PERK is activated in response to a variety of endoplasmic reticulum stresses implicated in numerous disease states. PERK regulates proliferation of beta cells during embryonic and neonatal development and is essential for viability of acinar cells in mouse exocrine pancreas, neither of which is associated with endoplasmic reticulum stress response. PERK is also required for endoplasmic reticulum functions including proinsulin trafficking and quality control in beta cells. Similarly, PERK modulates proliferation and differentiation of osteoblasts as well as secretion of type I collagen. PERK phosphorylates α subunit of the translation ...
Gentaur molecular products has all kinds of products like :search , EIAab \ CLIA 58 kDa glucose-regulated protein,58 kDa microsomal protein,Disulfide isomerase ER-60,Endoplasmic reticulum resident protein 57,Endoplasmic reticulum resident protein 60,ER protein 57,ER protein 6 \ U1497r for more molecular products just contact us
Ribophorins I and II, two transmembrane glycoproteins characteristic of the rough endoplasmic reticulum (ER) are thought to be part of the translocation apparatus for proteins made on membrane bound polysomes. To study the stoichiometry between ribophorins and membrane-bound ribosomes we have determined the RNA and ribophorin content in rat liver microsomes or in microsomal subfractions of different density (i.e., ribosome content). The specificity of antibodies against the ribophorins was demonstrated by Western blot analysis of rat liver rough microsomes separated by 2-dimensional gel electrophoresis. The ribophorin content of microsomal subfractions was determined by indirect immunoprecipitation and for ribophorin I by a radioimmune assay. In the latter assay a molar ratio of ribophorin I/ribosomes approaching one was calculated for total microsomes as well as in the gradient subfractions. We therefore suggest that ribophorins mediate the binding of ribosomes to endoplasmic reticulum ...
Oxidative Medicine and Cellular Longevity is a unique peer-reviewed, Open Access journal that publishes original research and review articles dealing with the cellular and molecular mechanisms of oxidative stress in the nervous system and related organ systems in relation to aging, immune function, vascular biology, metabolism, cellular survival and cellular longevity. Oxidative stress impacts almost all acute and chronic progressive disorders and on a cellular basis is intimately linked to aging, cardiovascular disease, cancer, immune function, metabolism and neurodegeneration. The journal fills a significant void in todays scientific literature and serves as an international forum for the scientific community worldwide to translate pioneering
Probable lectin that binds selectively to improperly folded lumenal proteins. May function in endoplasmic reticulum quality control and endoplasmic reticulum-associated degradation (ERAD) of both non-glycosylated proteins and glycoproteins.
In a previous study we reported the presence of a large conductance K+ channel in the membrane of endoplasmic reticulum (ER) from rat hepatocytes. The channel open probability (Po) appeared voltage dependent and reached to a minimum 0.2 at +50 mV. Channel activity in this case was found to be totally inhibited at ATP concentration 2.5 mM, glibenclamide 100 μM and tolbutamide 400 μM. Existing evidence indicates an impairment of endoplasmic reticulum functions in ER stress condition. Because ER potassium channels have been involved in several ER functions including cytoprotection, apoptosis and calcium homeostasis, a study was carried out to consider whether the ER potassium channel function is altered in a high fat diet model of ER stress. Male Wistar rats were made ER stress for 2 weeks with a high fat diet. Ion channel incorporation of ER stress model into the bilayer lipid membrane allowed the characterization of K+ channel. Our results indicate that the channel Po was significantly ...
ENCODES a protein that exhibits enzyme binding (ortholog); ubiquitin conjugating enzyme binding (ortholog); ubiquitin protein ligase activity (ortholog); INVOLVED IN proteasomal protein catabolic process (ortholog); proteasome-mediated ubiquitin-dependent protein catabolic process (ortholog); protein K48-linked ubiquitination (ortholog); PARTICIPATES IN Endoplasmic Reticulum-associated degradation pathway; ASSOCIATED WITH familial adult myoclonic epilepsy 3 (ortholog); FOUND IN endoplasmic reticulum (ortholog); integral component of endoplasmic reticulum membrane (ortholog); integral component of membrane (ortholog); INTERACTS WITH bis(2-ethylhexyl) phthalate; chromium(6+); ethanol
Substrate recognition component of a SCF (SKP1-CUL1-F-box protein) E3 ubiquitin-protein ligase complex that mediates the ubiquitination and subsequent proteasomal degradation of target proteins. Involved in the endoplasmic reticulum-associated degradation pathway (ERAD) for misfolded lumenal proteins by recognizing and binding sugar chains on unfolded glycoproteins that are retrotranslocated into the cytosol and promoting their ubiquitination and subsequent degradation. Prevents formation of cytosolic aggregates of unfolded glycoproteins that have been retrotranslocated into the cytosol. Able to recognize and bind denatured glycoproteins, preferentially those of the high-mannose type (By similarity).
Cardiovascular disease constitutes a major and increasing health burden in developed countries. Although treatments have progressed, the development of novel treatments for patients with cardiovascular diseases remains a major research goal. The endoplasmic reticulum (ER) is the cellular organelle in which protein folding, calcium homeostasis, and lipid biosynthesis occur. Stimuli such as oxidative stress, ischemic insult, disturbances in calcium homeostasis, and enhanced expression of normal and/or folding-defective proteins lead to the accumulation of unfolded proteins, a condition referred to as ER stress. ER stress triggers the unfolded protein response (UPR) to maintain ER homeostasis. The UPR involves a group of signal transduction pathways that ameliorate the accumulation of unfolded protein by increasing ER-resident chaperones, inhibiting protein translation and accelerating the degradation of unfolded proteins. The UPR is initially an adaptive response but, if unresolved, can lead to apoptotic
The biogenesis of nascent proteins translocated into the calcium‐rich, oxidizing milieu of the endoplasmic reticulum (ER) lumen is assisted by a group of resident ER proteins that include molecular chaperones and folding enzymes. These specialized ER proteins are constitutively expressed in all cells, where they play a role in monitoring and assisting the maturation of normal proteins (Gething and Sambrook, 1992; Hendrick and Hartl, 1993) and are essential for proper steady‐state operations of the eukaryotic secretory pathway. Expression of mutant secretory pathway proteins or exposure of cells to agents that adversely affect ER protein folding and maturation all result in the accumulation of unfolded proteins in the ER, thereby activating an inter‐organelle signaling pathway linking the ER and nucleus. This response, termed the unfolded protein response (UPR), includes the coordinate transcriptional up‐regulation of ER chaperones and folding enzymes (Lee, 1992).. In yeast, an ER ...
There are many contact sites of ER-PM in different cell types. The function of ER-plasma membrane contact sites is similar to that of the mitochondria-ER junctions, since Ca2+ homeostasis and lipid synthesis and trafficking take place there. As mentioned above, Ca2+ regulation is crucial as it is also responsible for protein synthesis, folding, and signaling. In excitable cells, the global calcium signal is generated by the coupling of PM depolarization and ER calcium release. In non-excitable cells, calcium influx is controlled by detecting luminal ER Ca2+ levels. Research has showed that the PM-ER contact site is involved in non-vesicular lipid trafficking. We know that lipids are insoluble in water. So to transfer lipid from its synthesis sites to its desired work place, one must shield the lipid. In fact, couple families of lipid transfer protein (LTPs) that can perform this task have been found on the contact sites. One of them is oxysterol-binding protein (OSBP) related proteins(ORPS). The ...
Plant cells, like cells from other kingdoms, have the ability to self-destruct in a genetically controlled manner. This process is defined as Programmed Cell Death (PCD). PCD can be triggered by various stimuli in plants including by endoplasmic reticulum (ER) stress. Research in the past two decades discovered that disruption of protein homeostasis in the endoplasmic reticulum (ER) could cause ER stress, which when prolonged/unresolved leads cells into PCD. ER stress-induced PCD is part of several plant processes, for instance, drought and heat stress have been found to elicit ER stress-induced PCD. Despite the importance of ER stress-induced PCD in plants, its regulation remains largely unknown, when compared with its counterpart in animal cells. In mammalian cells, several pro-apoptotic proteases called caspases were found to play a crucial role in ER stress-induced PCD. Over the past decade, several key proteases with caspase-like enzymatic activity have been discovered in plants and implicated in
The endoplasmic reticulum is a major organelle in all eukaryotic cells which performs multiple functions including protein and lipid synthesis and sorting, drug metabolism, and Ca 2+ storage and release. The endoplasmic reticulum, and its specialized muscle counterpart the sarcoplasmic reticulum, is the largest and most extensive of Ca 2+ storage organelle in eukaryotic cells, often occupying in excess of 10% of the cell volume. There are three major components of Ca 2+ storage organelles which mediate their major functions: Ca 2+ uptake, mediated by pumps and exchangers; storage enhanced by luminal Ca 2+ binding proteins, and Ca 2+ mobilization mediated by specific ion channels. Ca 2+ mobilization from the endoplasmic reticulum plays a central role in Ca 2+ signaling. Through Ca 2+ release channels in its membrane, the pervading and plastic structure of the endoplasmic reticulum allows Ca 2+ release to be rapidly targeted to specific cytoplasmic sites across the whole cell. That several
Communication between organelles is essential to coordinate cellular functions and the cells response to physiological and pathological stimuli. Organellar communication occurs at membrane contact sites (MCSs), where the endoplasmic reticulum (ER) membrane is tethered to cellular organelle membranes by specific tether proteins and where lipid transfer proteins and cell signaling proteins are located. MCSs have many cellular functions and are the sites of lipid and ion transfer between organelles and generation of second messengers. This review discusses several aspects of MCSs in the context of lipid transfer, formation of lipid domains, generation of Ca2+ and cAMP second messengers, and regulation of ion transporters by lipids. ...
Misfolded proteins of the endoplasmic reticulum (ER) are targeted to the cytoplasm for proteasomal degradation. Key components of this process are ER membrane-bound ubiquitin ligases. These ligases associate with the cytoplasmic AAA-ATPase Cdc48p/p97, which is thought to support the release of malfolded proteins from the ER. Here, we characterize a yeast protein complex containing the ubiquitin ligase Hrd1p and the ER membrane proteins Hrd3p and Der1p. Hrd3p binds malfolded proteins in the ER lumen enabling their delivery to downstream components. Therefore, we propose that Hrd3p acts as a substrate recruitment factor for the Hrd1p ligase complex. Hrd3p function is also required for the association of Cdc48p with Hrd1p. Moreover, our data demonstrate that recruitment of Cdc48p depends on substrate processing by the Hrd1p ligase complex. Thus, the Hrd1p ligase complex unites substrate selection in the ER lumen and polyubiquitination in the cytoplasm and links these processes to the release of ER ...
A summary of the article is shown below:. Purpose: The aim of the study was to examine the effects of resveratrol upon hepatic endoplasmic reticulum stress (ERS) and insulin sensitivity in vivo and in vitro. Material and methods: C57BL/6J mice were fed a high-fat diet (HFD) for 8 weeks, and insulin resistance was evaluated by the intraperitoneal glucose tolerance test (IPGTT). Mice were then treated with resveratrol for 12 weeks and blood and liver samples collected. Blood biochemical indicators were determined by kits, liver protein expression was determined by western blot, and morphological changes were observed by histological staining. Palmitic acid (PA)-induced insulin-resistant HepG2 cells were established. Cells were exposed to 100, 50 or 20 μM resveratrol for 24 hrs, and proliferation/cytotoxicity was determined. Cells were divided into five groups: control, PA, PA + Rev (100 μM), PA + Rev (50 μM) and PA + Rev (20 μM) groups. After 24 hrs of treatment, cellular proteins were ...
Engagement of the TNF receptor family of death receptors, including TNF-R1, Fas, Trail-R1, and Trail-R2, with their cognate ligands leads to the recruitment and autoactivation of initiator procaspase-8 (Krammer, 2000). Recent studies implicate that caspase-8 substrates located at distinct cellular loci play key roles in mediating death receptor-induced apoptosis. For example, caspase-8 cleavage of the BH3-only molecule BID promotes mitochondrial release of cyt.c and Smac/Diablo (Yin et al., 1999; Li et al., 2002); cleavage of RIP prevents the activation of NF-κB survival responses (Lin et al., 1999); and cleavage of the cytolinker plectin is important for disassembly of microfilaments (Stegh et al., 2000). In this work, we investigated the consequence of caspase-8 cleavage of BAP31 at the ER by expressing the pro-apoptotic p20 cleavage fragment in cells using an adenovirus vector. This approach allowed us to isolate and delineate a predicted branch of the death receptor signaling cascade. ...
TY - JOUR. T1 - Chemical chaperones reduce ionizing radiation-induced endoplasmic reticulum stress and cell death in IEC-6 cells. AU - Lee, Eun Sang. AU - Lee, Hae June. AU - Lee, Yoon Jin. AU - Jeong, Jae Hoon. AU - Kang, Seong Man. AU - Lim, Young Bin. PY - 2014/7/25. Y1 - 2014/7/25. N2 - Radiotherapy, which is one of the most effective approaches to the treatment of various cancers, plays an important role in malignant cell eradication in the pelvic area and abdomen. However, it also generates some degree of intestinal injury. Apoptosis in the intestinal epithelium is the primary pathological factor that initiates radiation-induced intestinal injury, but the mechanism by which ionizing radiation (IR) induces apoptosis in the intestinal epithelium is not clearly understood. Recently, IR has been shown to induce endoplasmic reticulum (ER) stress, thereby activating the unfolded protein response (UPR) signaling pathway in intestinal epithelial cells. However, the consequences of the IR-induced ...
Obesity-induced endoplasmatic reticulum (ER) stress has been demonstrated to underlie the induction of obesity-induced JNK and NF-kappa B activation inflammatory responses, and generation of peripheral insulin resistance. On the other hand, exercise has been used as a crucial tool in obese and diabetic patients, and may reduce inflammatory pathway stimulation. However, the ability of exercise training to reverse endoplasmatic reticulum stress in adipose and hepatic tissue in obesity has not been investigated in the literature. Here, we demonstrate that exercise training ameliorates ER stress and insulin resistance in DIO-induced rats. Rats were fed with standard rodent chow (3,948 kcal kg(-1)) or high-fat diet (5,358 kcal kg(-1)) for 2 months. After that rats were submitted to swimming training (1 h per day, 5 days for week with 5% overload of the body weight for 8 weeks). Samples from epididymal fat and liver were obtained and western blot analysis was performed. Our results showed that ...
Ca2+ ions are important second messengers in many cellular signal transduction pathways. Compromised Ca2+ homeostasis and signaling have been linked to many human diseases, including muscle dysfunction and heart failure.1-5 Two principal sources provide Ca2+ to the cell: channels in the plasma membrane (PM) that allow external Ca2+ to enter the cell and internal stores sequestered in the endoplasmic reticulum (ER) or sarcoplasmic reticulum (SR) that release Ca2+. Junctional membrane complexes between PM and ER/SR are present in all excitable cells, providing effective mechanisms for cross-talk between Ca2+ channels/transporters in the PM and Ca2+ release channels in intracellular membranes.6-10 A central focus in cardiovascular research is to understand the basic mechanisms that underlie the control of Ca2+ signaling in the heart and to search for ways to correct the defective Ca2+ signaling process associated with arrhythmogenesis and heart failure.. In the heart, entry of extracellular Ca2+ ...
We have used proteolysis to examine the environment through which nascent secretory proteins are translocated across the membrane of the endoplasmic reticulum. After solubilization of rough microsomes with detergent, fragments comprised of the approximately 70 carboxyl-terminal amino acids of translocating nascent chains initiated and targeted in vivo were protected from digestion by added proteases. About 40 amino acids of nascent chains were protected from proteolysis by the ribosome; thus, membrane-derived components protect an additional 30 amino acids. Under conditions in which those 30 additional amino acids are protected, only a small set of integral membrane proteins remained associated with the ribosome. These proteins include the Sec61 complex previously identified as the core component of the membrane-bound protein translocation apparatus. These results support the concept of a translocation pore that makes intimate contact with the ribosome and thereby protects nascent chains from ...
The endoplasmic reticulum (ER) is a subcellular organelle where proteins are folded with the help of lumenal chaperones. Newly synthesized peptides enter the ER via the sec61 pore and are glycosylated. Correctly folded proteins are packaged into transport vesicles that shuttle them to the Golgi complex. Misfolded proteins are retained within the ER lumen in complex with molecular chaperones. Proteins that are terminally misfolded bind to BiP and are directed toward degradation through the proteasome in a process called ER-associated degradation (ERAD). Accumulation of misfolded proteins in the ER causes ER stress and activates a signaling pathway called the unfolded protein response (UPR). In certain severe situations, however, the protective mechanisms activated by the UPR are not sufficient to restore normal ER function and cells die by apoptosis ...
LIPID TRANSFER PROTEINS AND MEMBRANE CONTACT SITES IN HUMAN CANCER FEBRUARY 12, 2020: Presentation from Sima Lev about the lipid transfer proteins in cancer.
ATF6, a membrane-anchored transcription factor from the endoplasmic reticulum (ER) that modulates the cellular response to stress as an effector of the unfolded-protein response (UPR), is a key player in the development of tumors of different origin. reticulum (ER) can be particularly affected by the presence of mutations in secretory proteins or by dynamic changes in the cellular microenvironment, events which are often encountered in cancers. In the ER, these events are sensed by specific sensors, which in turn trigger select Rabbit Polyclonal to CPB2 signaling pathways, collectively named the unfolded-protein response (UPR) (1). The UPR is an adaptive response that allows the cells to either overcome the stress or promote cell death in the case of overwhelming burden (1). Three ER-resident proteins, namely, the protein kinase PKR-like ER kinase (PERK), the inositol-requiring protein 1 alpha (IRE1), and the activating transcription factor 6 alpha (ATF6), have been identified as the major ...
Being a major factory for protein synthesis, assembly, and export, the endoplasmic reticulum (ER) has a precise and robust ER quality control (ERQC) system monitoring its product line. However, when organisms are subjected to environmental stress, whether biotic or abiotic, the levels of misfolded proteins may overwhelm the ERQC system, tilting the balance between the capacity of and demand for ER quality control and resulting in a scenario termed ER stress. Intense or prolonged ER stress may cause damage to the ER as well as to other organelles, or even lead to cell death in extreme cases. To avoid such serious consequences, cells activate self-rescue programs to restore protein homeostasis in the ER, either through the enhancement of protein-folding and degradation competence or by alleviating the demands for such reactions. These are collectively called the unfolded protein response (UPR). Long investigated in mammalian cells and yeasts, the UPR is also of great interest to plant scientists. Among
TY - JOUR. T1 - LHS1 and SIL1 provide a lumenal function that is essential for protein translocation into the endoplasmic reticulum. AU - Tyson, John R. AU - Stirling, Colin J. PY - 2000. Y1 - 2000. N2 - Lhs1p is an Hsp70-related chaperone localized in the endoplasmic reticulum (ER) lumen. Δlhs1 mutant cells are viable but are constitutively induced for the unfolded protein response (UPR). Here, we demonstrate a severe growth defect in Δire1Δlhs1 double mutant cells in which the UPR can no longer be induced. In addition, we have identified a UPR- regulated gene, SIL1, whose overexpression is sufficient to suppress the Δire1Δlhs1 growth defect. SIL1 encodes an ER-localized protein that interacts directly with the ATPase domain of Kar2p (BiP), suggesting some role in modulating the activity of this vital chaperone. SIL1 is a non-essential gene but the Δlhs1Δsil1 double mutation is lethal and correlates with a complete block of protein translocation into the ER. We conclude that the ...
Standard treatment for advanced malignant pleural mesothelioma (MPM) is a cisplatin/pemetrexed (MTA) regimen; however, this is confronted by drug resistance. Proteotoxic stress in the endoplasmic reticulum (ER) is a hallmark of cancer and some rely on this stress signalling in response to cytotoxic chemotherapeutics. We hypothesise that ER stress and the adaptive unfolded protein response (UPR) play a role in chemotherapy resistance of MPM. In vitro three-dimensional (3D) and ex vivo organotypic culture were used to enrich a chemotherapy-resistant population and recapitulate an in vivo MPM microenvironment, respectively. Markers of ER stress, the UPR and apoptosis were assessed at mRNA and protein levels. Cell viability was determined based on acid phosphatase activity. MPM cells with de novo and/or acquired chemotherapy resistance displayed low ER stress, which rendered the cells hypersensitive to agents that induce ER stress and alter the UPR. Bortezomib, an FDA-approved proteasome inhibitor,
The endoplasmic reticulum (ER) is an intracellular organelle for protein folding, lipid synthesis and Ca²⁺ storage. It is also responsible for the transportation for most of the secretory and transmembrane proteins. When the protein load exceeds the ER folding capacity, the ER undergoes stress and activates a set of signaling cascades that is termed the unfolded protein response (UPR). The multifunctional GRP78 is the major ER molecular chaperone with protein folding abilities and the master regulator of the UPR, and recently has been shown that a subfraction of it is localized on the cell surface acting as a co-receptor for various signaling pathway activation. ❧ Traditionally GRP78 is regarded as protective against hypoxia and nutrient starvation prevalent in the microenvironment of solid tumors, thus, its role in the development of hematologic malignancies remains to be determined. In this thesis, elevated GRP78 expression was detected in leukemic blasts of adult patients, leukemia cell ...
Diabetes is intimately associated with cardiovascular complications. Much evidence highlighted the complex interplay between Endoplasmic Reticulum (ER) stress and oxidative stress in the pathogenesis of diabetes. Hemeoxygenase-1 (HO-1) induction was shown to protect against oxidative stress in diabetes; however the underlying molecular mechanisms have not yet been fully elucidated. We aim in this project to test the hypothesis that HO-1 induction will protect against high glucose-mediated ER stress and oxidative stress in endothelial cells and will enhance cell survival. Endothelial cells were cultured in physiological or high concentrations of glucose in the presence of cobalt protoporphyrin 1X (CoPP, HO-1 inducer), 4-phenylbutyrate (PBA, chemical chaperone to inhibit ER stress) or vehicle. Then, ER stress response was assessed (PCR, western blot). The productions of ROS (flow cytometer) and NO (Griess assay) were analysed. Also, apoptosis and caspase 3/7 activity were assessed. High glucose treatment
1.Radons,J. The human HSP70 family of chaperones: where do we stand? Cell Stress Chaperones 21, 379-404 (2016).[PubMed]. 2.Zuiderweg,E.R., Hightower,L.E., & Gestwicki,J.E. The remarkable multivalency of the Hsp70 chaperones. Cell Stress Chaperones 22, 173-189 (2017).[PubMed]. 3.Braakman,I. & Bulleid,N.J. Protein folding and modification in the mammalian endoplasmic reticulum. Annu. Rev. Biochem. 80, 71-99 (2011).[PubMed]. 4.Genereux,J.C. et al. Unfolded protein response-induced ERdj3 secretion links ER stress to extracellular proteostasis. EMBO J. 34, 4-19 (2015). [PubMed]. 5.Cook,K.L. et al. Endoplasmic reticulum stress protein GRP78 modulates lipid metabolism to control drug sensitivity and antitumor immunity in breast cancer. Cancer Res. 76, 5657-5670 (2016).[PubMed]. 6.Gonzales,P.A. et al. Large-scale proteomics and phosphoproteomics of urinary exosomes. J. Am. Soc. Nephrol. 20, 363-379 (2009).[PubMed]. 7.Prunotto,M. et al. Proteomic analysis of podocyte exosome-enriched fraction from normal ...
Protein targeting to the endoplasmic reticulum can be either co- or posttranslational and involves the binding of a hydrophobic signal sequence by delivery factors such as signal recognition particle or components of the TRC/GET pathway, respectively (1). Inefficient recognition and/or delivery of precursor proteins destined for the endoplasmic reticulum can lead to their cytosolic accumulation, resulting in toxicity such as that observed in neurodegenerative disorders such as prionopathies (2, 3). The disposal of such mislocalized proteins in mammalian cells has recently been shown to depend on the BAG6 complex comprised of the BAG6 protein together with TRC35 and UBL4A. The BAG6 complex recognizes mislocalized proteins, recruits the E2 conjugating enzyme, UbcH5, and an unidentified E3 ligase(s), and thereby selectively promotes the rapid ubiquitination and proteasomal degradation of these substrates (4). This role for the BAG6 complex in cytosolic quality control extends other studies showing ...
The majority of patients with pancreatic ductal adenocarcinoma (PDA) develop metastatic disease after resection of their primary tumor. We found that livers from patients and mice with PDA harbor single, disseminated cancer cells (DCCs) lacking expression of cytokeratin-19 (CK19) and major histocompatibility complex class I (MHCI). We created a mouse model to determine how these DCCs develop. Intra-portal injection of immunogenic PDA cells into pre-immunized mice seeded livers only with single, non-replicating DCCs that were CK19(-) and MHCI(-) The DCCs exhibited an endoplasmic reticulum (ER) stress response but, paradoxically lacked both inositol-requiring enzyme 1alpha activation and expression of the spliced form of transcription factor XBP1 (XBP1s). Inducible expression of XBP1s in DCCs, in combination with T cell-depletion, stimulated the outgrowth of macro-metastatic lesions that expressed CK19 and MHCI. Thus, unresolved ER stress enables DCCs to escape immunity and establish latent ...
The biogenesis of most membrane proteins is governed by specific interactions between the newly synthetized nascent polypeptide chain and the evolutionary conserved and essential insertases and translocases (1-3). Insertases and translocases recognize their substrate and lower the free-energy barrier for inserting and folding the polypeptide into cellular membranes (3, 4). This insertion and folding can occur cotranslationally as the polypeptide exits the ribosome or posttranslationally after the polypeptide has been released by the ribosome. The bacterial translocase SecYEG has a eukaryotic homolog, Sec61, in the endoplasmatic reticulum (1), whereas the bacterial insertase YidC has Oxa1 and Oxa2 homologs in mitochondria, Get1 in endoplasmatic reticulum, and Alb3 in chloroplasts (5-7). In Gram-negative bacteria, SecYEG folds α-helical membrane proteins into the inner membrane and translocates precursors of soluble periplasmic and β-barrel outer membrane proteins to the periplasm (1, 8). ...
The endoplasmic reticulum (ER) is an intracellular organelle for protein folding, lipid synthesis and Ca2+ storage. It also is responsible for transporting most secreted and transmembrane proteins to their proper cellular locations. ER undergoes stress when the protein load exceeds its folding capacity, and cellular signaling cascades are activated as unfolded protein response (UPR). GRP78 is a major chaperone assisting protein folding, as well as a master regulator of UPR signaling. In this thesis, we discovered that heterozygosity of Grp78 enhances energy expenditure through upregulation of mitochondria activity, and alleviate high fat diet (HFD)-induced obesity and type 2 diabetes in mouse. The latter is also achieved through increase in insulin sensitivity in the white adipose tissue (WAT) of HFD-fed Grp78+/- mice, with adaptive UPR improving ER folding capacity and quality control. This mechanism is validated through overexpression of the active form of ATF6, a transcription factor known to ...
Hypoxia is an important factor that contributes to tumour aggressiveness and correlates with poor prognosis and resistance to conventional therapy. Therefore, identifying hypoxic environments within tumours is extremely useful for understanding cancer biology and developing novel therapeutic strategies. Several studies have suggested that carbonic anhydrase 9 (CA9) is a reliable biomarker of hypoxia and a potential therapeutic target, while pimonidazole has been identified as an exogenous hypoxia marker. However, other studies have suggested that CA9 expression is not directly induced by hypoxia and it is not expressed in all types of tumours. Thus, in this study, we focused on endoplasmic reticulum disulphide oxidase 1α (ERO1α), a protein that localises in the endoplasmic reticulum and is involved in the formation of disulphide bonds in proteins, to determine whether it could serve as a potential tumour-hypoxia biomarker. Using quantitative real-time polymerase chain reaction, we analysed the mRNA
Apoptosis is essential for normal development and maintenance of homeostasis, and disruption of apoptotic pathways is associated with multiple disease states, including cancer. Although initially identified as central regulators of apoptosis at the level of mitochondria, an important role for BCL-2 proteins at the endoplasmic reticulum is now well established. Signaling pathways emanating from the endoplasmic reticulum (ER) are involved in apoptosis initiated by stimuli as diverse as ER stress, oncogene expression, death receptor (DR) ligation and oxidative stress, and the BCL-2 family is almost invariably implicated in the regulation of these pathways. This also includes Ca2+-mediated cross talk between ER and mitochondria during apoptosis, which contributes to the mitochondrial dynamics that support the core mitochondrial apoptosis pathway. In addition to the regulation of apoptosis, BCL-2 proteins at the ER also regulate autophagy, a survival pathway that limits metabolic stress, genomic instability
Endoplasmic reticulum (ER) stress is a common feature of Parkinsons disease (PD), and several PD-related genes are responsible for ER dysfunction. Recent studies suggested LRRK2-G2019S, a pathogenic mutation in the PD-associated gene LRRK2, cause ER dysfunction, and could thereby contribute to the development of PD. It remains unclear, however, how mutant LRRK2 influence ER stress to control cellular outcome. In this study, we identified the mechanism by which LRRK2-G2019S accelerates ER stress and cell death in astrocytes. To investigate changes in ER stress response genes, we treated LRRK2-wild type and LRRK2-G2019S astrocytes with tunicamycin, an ER stress-inducing agent, and performed gene expression profiling with microarrays. The XBP1 SUMOylation and PIAS1 ubiquitination were performed using immunoprecipitation assay. The effect of astrocyte to neuronal survival were assessed by astrocytes-neuron coculture and slice culture systems. To provide in vivo proof-of-concept of our approach, we measured
Cereal α-amylases (EC are typical secretory proteins found in many plants. In germinating cereal seeds, these enzyme molecules are biosynthesized and secreted from the secretory tissues, the scutellar epithelium and the aleurone, to the starchy endosperm, which has undergone programmed cell death. Numerous α-amylase isoforms have been identified in cereals, but the predominant α-amylase isoform I-1 (AmyI-1) in rice (Oryza sativa) is a unique glycoprotein that bears N-linked oligosaccharide side chains (Hayashi et al., 1990; Terashima et al., 1994). The biosynthesis and secretion of AmyI-1 have been extensively investigated: mRNA translation on endoplasmic reticulum (ER) membrane-bound ribosomes, signal sequence-dependent translocation of the ER, core glycosylation in the ER lumen, vesicular transport to the Golgi apparatus, oligosaccharide modification to the complex type, and exocytosis all proceed according to the canonical secretory mechanism (Palade, 1975; Blobel, 1980; Kornfeld ...
Hypoxia activates all components of the unfolded protein response (UPR), a stress response initiated by the accumulation of unfolded proteins within the endoplasmic reticulum (ER). Our group and others have shown previously that the UPR, a hypoxia-inducible factor-independent signaling pathway, mediates cell survival during hypoxia and is required for tumor growth. Identifying new genes and pathways that are important for survival during ER stress may lead to the discovery of new targets in cancer therapy. Using the set of 4,728 homozygous diploid deletion mutants in budding yeast, Saccharomyces cerevisiae, we did a functional screen for genes that conferred resistance to ER stress-inducing agents. Deletion mutants in 56 genes showed increased sensitivity under ER stress conditions. Besides the classic UPR pathway and genes related to calcium homeostasis, we report that two additional pathways, including the SLT2 mitogen-activated protein kinase (MAPK) pathway and the osmosensing MAPK pathway, ...
Looking for online definition of Calcium Homeostasis Endoplasmic Reticulum Protein in the Medical Dictionary? Calcium Homeostasis Endoplasmic Reticulum Protein explanation free. What is Calcium Homeostasis Endoplasmic Reticulum Protein? Meaning of Calcium Homeostasis Endoplasmic Reticulum Protein medical term. What does Calcium Homeostasis Endoplasmic Reticulum Protein mean?
Our genetic screen for suppressors that restore defective ERAD in cdc48-10 cells identified Ssz1p. Being a member of the Hsp70 family, we considered the possibility that Ssz1p acted as a cytosolic chaperone that functions in ERAD by either activating or replacing the defective Cdc48p. The ability of Ssz1p to partially restore the impaired 6myc-Hmg2 degradation in ufd1-2 and npl4-1 mutants could have suggested that Ssz1p replaced the entire Cdc48p-Ufd1p-Npl4p complex in its role in ERAD. However, Ssz1p was not an essential ERAD factor and we could not detect any interaction of Ssz1p with the ERAD-M substrate 6myc-Hmg2. Moreover, Ssz1p is an unusual chaperone (Gautschi et al. 2001; Gautschi et al. 2002; Hundley et al. 2002; Shaner and Morano 2007), and therefore, we attributed its ability to correct ERAD to other functions of this Hsp70 member.. On the basis of the RAC-independent participation of Ssz1p in the PDR network, we examined whether other PDR members might be linked to ERAD. Indeed, ...
Transition zones are associated with the Golgi stacks. They are close to each other. This makes sense because the communication is more efficient. Vesicles dont need to travel long distances and the existence of the Golgi apparatus itself depends on a continuous process of vesicle incoming. It has been observed that a new transition zone led quickly to the nearby formation of a new Golgi stack. On the contrary, if a transition zone disappears, the associated Golgi cisternae are also lost. Transition zones can fuse with others and one transition zone can be split in two. Their associated Golgi stacks match this behavior. Vesicles budding from the transition zones are COPII coated vesicles ( COPII: coat protein II; Figure 1). Several proteins are involved in the formation of this COPII molecular framework: Sec16, Sar1 GTPases, Sec23/24 and Sec13/31. In this order, they are assembled at the cytosolic surface of the transition zone membranes. Transition zones are the more suitable environments for ...
TY - JOUR. T1 - Reconstitution of sterol-regulated endoplasmic reticulum-to-Golgi transport of SREBP-2 in insect cells by co-expression of mammalian SCAP and Insigs. AU - Dobrosotskaya, Irina Y.. AU - Goldstein, Joseph L.. AU - Brown, Michael S.. AU - Rawson, Robert B.. PY - 2003/9/12. Y1 - 2003/9/12. N2 - In mammalian cells, membrane-bound sterol regulatory element-binding proteins (SREBPs) are transported from ER to Golgi where they are processed proteolytically to generate soluble transcription factors that activate lipid synthesis. ER-to-Golgi transport requires SCAP, a sterol-regulated escort protein. In sterol-treated cells, the SCAP/SREBP complex binds to Insig-1 or Insig-2, which retains the complex in the ER, blocking SREBP processing and decreasing lipid synthesis. In Drosophila cells, the endogenous SCAP/SREBP complex is transported to Golgi, but transport is blocked by phosphatidylethanolamine instead of sterols. Here, we show that mammalian SREBP-2 is not transported to Golgi when ...
Since acetic acid inhibits the growth and fermentation ability of Saccharomyces cerevisiae, it is one of the practical hindrances to the efficient production of bioethanol from a lignocellulosic biomass. Although extensive information is available on yeast response to acetic acid stress, the involvement of endoplasmic reticulum (ER) and unfolded protein response (UPR) has not been addressed. We herein demonstrated that acetic acid causes ER stress and induces the UPR. The accumulation of misfolded proteins in the ER and activation of Ire1p and Hac1p, an ER-stress sensor and ER stress-responsive transcription factor, respectively, were induced by a treatment with acetic acid stress (| 0.2% v/v). Other monocarboxylic acids such as propionic acid and sorbic acid, but not lactic acid, also induced the UPR. Additionally, ire1∆ and hac1∆ cells were more sensitive to acetic acid than wild-type cells, indicating that activation of the Ire1p-Hac1p pathway is required for maximum tolerance to acetic acid.
TY - JOUR. T1 - An endoplasmic reticulum protein, Nogo-B, facilitates alcoholic liver disease through regulation of kupffer cell polarization. AU - Park, Jin Kyu. AU - Shao, Mingjie. AU - Kim, Moonyoung. AU - Baik, Soonkoo. AU - Cho, Meeyon. AU - Utsumi, Teruo. AU - Satoh, Ayano. AU - Ouyang, Xinsho. AU - Chung, Chuhan. AU - Iwakiri, Yasuko. PY - 2017/5/1. Y1 - 2017/5/1. N2 - Nogo-B (Reticulon 4B) is an endoplasmic reticulum (ER) resident protein that regulates ER structure and function. Because ER stress is known to induce M2 macrophage polarization, we examined whether Nogo-B regulates M1/M2 polarization of Kupffer cells and alters the pathogenesis of alcoholic liver disease (ALD). M1 and M2 phenotypes were assessed in relation to Nogo-B expression and disease severity in liver specimens from ALD patients (NCT01875211). Liver specimens from wild-type (WT) and Nogo-B knockout (KO) mice fed a control or Lieber-DeCarli ethanol liquid diet (5% ethanol) for 6 weeks were analyzed for liver injury ...
Tight repression of yeast endoplasmic reticulum stress sensor Ire1 by its N-terminal intrinsically disordered subdomainTight repression of yeast endoplasmic reticulum stress sensor Ire1 by its N-terminal intrinsically disordered subdomain ...
Human ER protein 44 ELISA Kit;Human ERp44 ELISA Kit;Human thioredoxin domain-containing protein 4 ELISA Kit;Human KIAA0573 ELISA Kit;Human TXNDC4 ELISA Kit;Human PDIA10 ELISA Kit;Human endoplasmic reticulum protein 44 ELISA Kit;Human endoplasmic reticulum resident protein 44 ELISA Kit;Human endoplasmic reticulum resident protein 44 kDa ELISA Kit;Human protein disulfide isomerase family A, member 10 ELISA Kit;Human thioredoxin domain containing 4 (endoplasmic reticulum) ELISA Kit ...
After axonal injury, chromatolysis (fragmentation of Nissl substance) occurs in both intrinsic neurons (whose processes are within the CNS) and extrinsic neurons (whose axons extend outside the CNS). Electron microscopy shows that chromatolysis involves fission of the rough endoplasmic reticulum. In intrinsic neurons (which do not regenerate axons) or in extrinsic neurons denied axon regeneration, chromatolysis is often accompanied by degranulation (loss of ribosomes from rough endoplasmic reticulum), disaggregation of polyribosomes and degradation of monoribosomes into dust-like particles. Ribosomes and rough endoplasmic reticulum may also be degraded in autophagic vacuoles by Ribophagy and Reticulophagy, respectively. In other words, chromatolysis is disruption of parts of the protein synthesis infrastructure. Whereas some neurons may show transient or no chromatolysis, severely injured neurons can remain chromatolytic and never again synthesise normal levels of protein; some may atrophy or die. What
Maize root tips were fixed in potassium permanganate, embedded in epoxy resin, sectioned to show silver interference color, and studied with the electron microscope. All the cells were seen to contain an endoplasmic reticulum and apparently independent Golgi structures.. The endoplasmic reticulum is demonstrated as a membrane-bounded, vesicular structure comparable in many aspects to that of several types of animal cells. With the treatment used here the membranes appear smooth surfaced. The endoplasmic reticulum is continuous with the nuclear envelope and, by contact at least, with structures passing through the cell wall. The nuclear envelope is characterized by discontinuities, as previously reported for animal cells. The reticula of adjacent cells seem to be in contact at or through the plasmodesmata. Because of these contacts the endoplasmic reticulum of a given cell appears to be part of an intercellular system.. The Golgi structures appear as stacks of platelet-vesicles which apparently ...
Obesity-mediated inflammation is a major cause of insulin resistance, and macrophages play an important role in this process. The 78-kDa glucose-regulated protein (GRP78) is a major endoplasmic reticulum chaperone that modulates unfolded protein response (UPR), and mice with GRP78 heterozygosity were resistant to diet-induced obesity. Here, we show that mice with macrophage-selective ablation of GRP78 (Lyz- GRP78(-/-)) are protected from skeletal muscle insulin resistance without changes in obesity compared with wild-type mice after 9 wk of high-fat diet. GRP78-deficient macrophages demonstrated adapted UPR with up-regulation of activating transcription factor (ATF)-4 and M2-polarization markers. Diet-induced adipose tissue inflammation was reduced, and bone marrow-derived macrophages from Lyz- GRP78(-/-) mice demonstrated a selective increase in IL-6 expression. Serum IL-13 levels were elevated by | 4-fold in Lyz- GRP78(-/-) mice, and IL-6 stimulated the myocyte expression of IL-13 and IL-13 receptor.
Propolis, a natural product collected from plants by honey bees, is commonly used in folk medicines. Endoplasmic reticulum (ER) stress is known to induce apoptosis through the induction of CCAAT/enhancer-binding protein homologous protein (CHOP). Here, we investigated whether ethanol extracts of pro …
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Fig. 1. Models of ER segregation in proliferating animal cells. In interphase (left panel), the peripheral ER forms an interconnected network that is contiguous with the outer membrane of the nuclear envelope. The outer nuclear membrane is biochemically similar to the peripheral ER membrane. By contrast, some integral membrane proteins are localized specifically to the inner nuclear membrane (yellow ovals) or to nuclear pores where the outer and inner nuclear membranes meet (red ovals). In one model of ER segregation (model a), the peripheral ER and the nuclear envelope undergo progressive vesiculation. By metaphase, the cell contains vesicles derived from the peripheral ER or outer nuclear membrane, and from the inner nuclear membrane or nuclear pore domains. Diffusion of these vesicles during metaphase and anaphase ensures the equal partition of ER elements. Another model (model b) predicts that the peripheral ER retains its integrity during mitosis. The nuclear envelope is absorbed into the ...
Membralin mutant mice manifest a severe and early-onset motor neuron disease with defects in endoplasmic reticulum-associated protein degradation.
GBRs (GABAB receptors; where GABA stands for γ-aminobutyric acid) are G-protein-coupled receptors that mediate slow synaptic inhibition in the brain and spinal cord. In vitro assays have previously demonstrated that these receptors are heterodimers assembled from two homologous subunits, GBR1 and GBR2, neither of which is capable of producing functional GBR on their own. We have used co-immunoprecipitation in combination with bioluminescence and fluorescence resonance energy transfer approaches in living cells to assess directly the interaction between GBR subunits and determine their subcellular localization. The results show that, in addition to forming heterodimers, GBR1 and GBR2 can associate as stable homodimers. Confocal microscopy indicates that, while GBR1/GBR1 homodimers are retained in the endoplasmic reticulum and endoplasmic reticulum-Golgi intermediate compartment, both GBR2/GBR2 homodimers and GBR1/GBR2 heterodimers are present at the plasma membrane. Although these observations ...
TY - JOUR. T1 - Nuclear pore disassembly from endoplasmic reticulum membranes promotes Ca2+ signalling competency. AU - Boulware, Michael J.. AU - Marchant, Jonathan S.. PY - 2008/6/15. Y1 - 2008/6/15. N2 - The functionality of the endoplasmic reticulum (ER) as a Ca2+ storage organelle is supported by families of Ca2+ pumps, buffers and channels that regulate Ca2+ fluxes between the ER lumen and cytosol. Although many studies have identified heterogeneities in Ca2+ fluxes throughout the ER, the question of how differential functionality of Ca2+ channels is regulated within proximal regions of the same organelle is unresolved. Here, we studied the in vivo dynamics of an ER subdomain known as annulate lamellae (AL), a cytoplasmic nucleoporin-containing organelle widely used in vitro to study the mechanics of nuclear envelope breakdown. We show that nuclear pore complexes (NPCs) within AL suppress local Ca+ signalling activity, an inhibitory influence relieved by heterogeneous dissociation of ...
Protein folding in the endoplasmic reticulum (ER) is error prone, and ER quality control (ERQC) processes ensure that only correctly folded proteins are exported from the ER. Glycoproteins can be retained in the ER by ERQC, and this retention contributes to multiple human diseases, termed ER storage diseases. UDP-glucose:glycoprotein glucosyltransferase (UGGT1) acts as a central component of glycoprotein ERQC, monoglucosylating deglucosylated N-glycans of incompletely folded glycoproteins and promoting subsequent reassociation with the lectin-like chaperones calreticulin and calnexin. The extent to which UGGT1 influences glycoprotein folding, however, has only been investigated for a few selected substrates. Using mouse embryonic fibroblasts lacking UGGT1 or those with UGGT1 complementation, we investigated the effect of monoglucosylation on the soluble/insoluble distribution of two misfolded alpha 1-antitrypsin (AAT) variants responsible for AAT deficiency disease: null Hong Kong (NHK) and Z ...
In an electron microsope study, the morphology of mature Paneth cells from the small intestine of adult rats is compared with that of differentiating Paneth cells from young rats 2 to 4 weeks old. All mature cells exhibit a marked polarity similar to that of other exocrine gland cells and contain a well developed endoplasmic reticulum, an elaborate Golgi complex, and numerous large secretory granules; they also possess an abundance of lysosomes. The most conspicuous occurrence in the process of differentiation is the development of the endoplasmic reticulum. The most immature Paneth cells possess an endoplasmic reticulum of the vesicular type, which, during maturation, is replaced by the characteristic lamellated ergastoplasm of the mature cell. At a certain stage of differentiation the cavities of the developing cisternae show numerous communications with the perinuclear space, suggesting an outgrowth of the ergastoplasm from the nuclear envelope. Furthermore, the cavities and the perinuclear ...
AIMS: In this study we investigated whether attenuation of endoplasmic reticulum stress (ER stress) could protect HepG2 cells from free fatty acid (FFA)-induced apoptosis. MAIN METHODS: Human liver cell line HepG2 cells were exposed to Sodium Palmitate (Pa) or Sodium Oleate (Ol). Apoptosis and ER stress of HepG2 cells were analyzed with flow cytometry, real-time RT-PCR and Western Blotting. An expression plasmid encoding for the ER chaperone immunoglobulin heavy chain-binding protein (Bip) was transfected into HepG2 cells to attenuate ER stress. Small interfering RNA siCHOP was used to knockdown the expression of C/EBP Homologous Protein (CHOP) in HepG2. KEY FINDINGS: Pa led to cytotoxicity and apoptosis in HepG2 cells in a dose-dependent pattern and also induced ER stress indicated by increased phosphorylation of eIF2alpha, upregulation of IRE1alpha and CHOP. Bip expression levels were slightly down regulated after Pa treatment. The unsaturated fatty acid, Ol, induced neither apoptosis nor ER stress in
TY - JOUR. T1 - Component of splicing factor SF3b plays a key role in translational control of polyribosomes on the endoplasmic reticulum. AU - Ueno, Tomonori. AU - Taga, Yuki. AU - Yoshimoto, Rei. AU - Mayeda, Akila. AU - Hattori, Shunji. AU - Ogawa-Goto, Kiyoko. PY - 2019/5/7. Y1 - 2019/5/7. N2 - One of the morphological hallmarks of terminally differentiated secretory cells is highly proliferated membrane of the rough endoplasmic reticulum (ER), but the molecular basis for the high rate of protein biosynthesis in these cells remains poorly documented. An important aspect of ER translational control is the molecular mechanism that supports efficient use of targeted mRNAs in polyribosomes. Here, we identify an enhancement system for ER translation promoted by p180, an integral ER membrane protein we previously reported as an essential factor for the assembly of ER polyribosomes. We provide evidence that association of target mRNAs with p180 is critical for efficient translation, and that SF3b4, ...
Despite the relevance of the eukaryotic endoplasmic reticulum (ER)-stress response as an integrator of multiple stress signals into an adaptive response, knowledge about these ER-mediated cytoprotective pathways in soybean (Glycine max) is lacking. Here, we searched for genes involved in the highly conserved unfolded protein response (UPR) and ER stress-induced plant-specific cell death signaling pathways in the soybean genome. Previously characterized Arabidopsis UPR genes were used as prototypes for the identification of the soybean orthologs and the in silico assembly of the UPR in soybean, using eggNOG v4.0 software. Functional studies were also conducted by analyzing the transcriptional activity of soybean UPR transducers. As a result of this search, we have provided a complete profile of soybean UPR genes with significant predicted protein similarities to A. thaliana UPR-associated proteins. Both arms of the plant UPR were further examined functionally, and evidence is presented that the soybean
Endoplasmic reticulum (ER)-associated degradation (ERAD) is a quality control mechanism that allows for targeted degradation of proteins in the ER. Zhou et al. found that a particular protein complex in ERAD, Sel1L-Hrd1, regulates the dynamics of another organelle, the mitochondrion, by altering ER-mitochondria contacts. Three-dimensional high-resolution imaging in brown adipocytes from cold-challenged mice revealed that defective ERAD led to the formation of enlarged and abnormally shaped mitochondria with perforating ER tubules. The authors explored the consequences of ERAD deficiency on mitochondrial function and thermogenesis, which provides insights into ERADmediated ER-mitochondrial cross-talk and advances our understanding of the physiological importance of interorganelle contact.. Science, this issue p. 54 ...
This work shows that the ubiquitous translocon complex in the endoplasmic reticulum membrane may act as a Ca2+ leak channel. The complex is not as tight as previously thought. Heritage and Wonderlin demonstrated that permeability of small polar molecules increased in cells treated with puromycin (Heritage and Wonderlin, 2001). Recently, it has been shown that the permeability of the ER to small polar molecules is coupled to translation (Roy and Wonderlin, 2003). In an initial study, we measured the effect of puromycin on the Ca2+ permeability of the ER membrane in mouse acinar pancreatic cells (Lomax et al., 2002). In the present work, we demonstrate that puromycin acts on the translocon to induce a Ca2+ leak in LNCaP cells and also that a physiological calcium leak through the translocon is possible at the end of termination when the ribosome is still in place. Puromycin is a potent translation inhibitor, specifically blocking the ribosome on the translocon and clearing the nascent peptide ...
Protein trafficking from the endoplasmic reticulum (ER) to the Golgi apparatus involves specific uptake into coat protein complex II (COPII)-coated vesicles of secretory and of vesicle targeting (v-SNARE) proteins. Here, two ER to Golgi v-SNAREs, Bet1p and Bos1p, were shown to interact specifically with Sar1p, Sec23p, and Sec24p, components of the COPII coat, in a guanine nucleotide-dependent fashion. Other v-SNAREs, Sec22p and Ykt6p, might interact more weakly with the COPII coat or interact indirectly by binding to Bet1p or Bos1p. The data suggest that transmembrane proteins can be taken up into COPII vesicles by direct interactions with the coat proteins and may play a structural role in the assembly of the COPII coat complex. ...
Antibodies for proteins involved in negative regulation of transcription from RNA polymerase II promoter in response to endoplasmic reticulum stress pathways, according to their Panther/Gene Ontology Classification
A growing epidemic of obesity and inflammatory bowel disease is threatening the health of millions of people around the world. Recent studies have established that these diseases are associated with systemic chronic inflammation and/or disrupted endoplasmic reticulum (ER) homeostasis. However, the role of inflammation and ER homeostasis in health and disease is not well understood. In this dissertation, I elucidate the physiological role of inflammasome, TLR signaling and ER associated degradation in various metabolic diseases. First, I show (Sun et al. Diabetes 2012) that the onset of obesity associated hyperglycemia and hyperinsulinemia coincides with the activation of the inflammasome in white adipose tissue. But unexpectedly, the ATP-P2X7 signaling axis, a well-known inflammasome-activating pathway, does not mediate the inflammasome activation. The nature of the inflammasome-activating danger signal(s) in adipose tissue in obesity remains to be characterized. Second, we report (Ji and Sun et ...
Several studies have correlated ER stress with myocardial damage. For example, the ER stress response is activated in the hearts of transgenic mice that overexpress monocyte chemoattractant protein-1 and develop heart failure,36 suggesting that in this model, the proapoptotic phase of ER stress contributes to the loss of myocardium associated with failure. In further support of a role for ER stress in heart failure is the finding that transgenic overexpression of a mutant KDEL receptor, an ER protein that facilitates ER protein targeting, activates the ER stress response in mouse hearts and causes dilated cardiomyopathy.69 Also, overexpression of the ER stress response gene product p53-upregulated modulator of apoptosis (PUMA) contributes to ER stress-mediated apoptosis in cultured cardiomyocytes70 and targeted deletion of PUMA in mouse hearts attenuates cardiomyocyte death during ex vivo I/R.71. In contrast to the studies cited above, other studies suggest that ER stress might protect the ...
The SHERP genes are found as a tandem pair within the differentially regulated LmcDNA16 locus of Leishmania major. The SHERP gene product (Small Hydrophilic Endoplasmic Reticulum-associated Protein) is unusual in its small size (6.2kDa), its acidic pI (4.6) and its exclusive, high-level expression ( 100000 copies per cell) in infective non-replicative parasite stages. No homologues have been found to date. Secondary-structure predictions suggest that SHERP contains an amphiphilic a-helix that is presumably involved in protein-protein interactions. SHERP has been localized to the endoplasmic reticulum as well as to the outer mitochondrial membrane in both wild-type and over-expressing parasites. Given the absence of an N-terminal signal sequence, transmembrane-spanning domains or detectable post-translational modifications, it is likely that this hydrophilic molecule is a peripheral membrane protein on the cytosolic face of intracellular membranes. This weak membrane association has been ...
Calcium (Ca2+) is a fundamental regulator of cell signaling and function. Thapsigargin (Tg) blocks the sarco/endoplasmic reticulum (ER) Ca2+-ATPase (SERCA), disrupts Ca2+ homeostasis, and causes cell death. However, the exact mechanisms whereby SERCA-inhibition induces cell death are incompletely understood. Here, we report that low (0.1 μM) concentrations of Tg and Tg analogs with various long-chain substitutions at the O(8) position extensively inhibit SERCA1a-mediated Ca2+ transport. We also found that in both prostate and breast cancer cells, exposure to Tg or Tg analogs for 1 day caused extensive drainage of the ER Ca2+ stores. This Ca2+ depletion was followed by markedly reduced cell proliferation rates and morphological changes that developed over 2-4 days and culminated in cell death. Interestingly, these changes were not accompanied by bulk increases in cytosolic Ca2+ levels. Moreover, knockdown of two key store-operated Ca2+ entry (SOCE) components, Orai1 and STIM1, did not reduce Tg ...
PhD Project - Characterisation of cell death pathways upon activation of the endoplasmic reticulum stress sensor IRE1alpha at Durham University, listed on FindAPhD.com
def: A protein complex that is located in the endoplasmic reticulum and is composed of chaperone proteins, including BiP, GRP94; CaBP1, protein disulfide isomerase (PDI), ERdj3, cyclophilin B, ERp72, GRP170, UDP-glucosyltransferase, and SDF2-L1. [PMID:12475965 ...
TY - JOUR. T1 - Role of the plant-specific endoplasmic reticulum stress-inducible gene TIN1 in the formation of pollen surface structure in Arabidopsis thaliana. AU - Iwata, Yuji. AU - Nishino, Tsuneyo. AU - Iwano, Megumi. AU - Takayama, Seiji. AU - Koizumi, Nozomu. N1 - KAUST Repository Item: Exported on 2020-10-01 Acknowledgements: We would like to thank GABI-Kat and TAIR for the T-DNA insertion mutant and the gene annotation data, respectively. This work was supported by Ministry of Education, Culture, Sports, Science, and Technology of Japan, Grant-in-Aid for Scientific Research 20380188 to N.K.. PY - 2012. Y1 - 2012. N2 - Accumulation of unfolded proteins in the endoplasmic reticulum (ER) of eukaryotic cells triggers the transcriptional activation of ER-resident molecular chaperones and folding enzymes to maintain cellular homeostasis. This process is known as the ER stress response or the unfolded protein response. We have identified tunicamycin induced 1 (TIN1), a plant-specific ER ...
Apoptotic DNA fragmentation may be a cooperative activity between caspase-activated deoxyribonuclease and the poly(ADP-ribose) polymerase-regulated DNAS1L3, an endoplasmic reticulum-localized endonucleasethat translocates to the nucleus during apoptosis. Journal of Biological Chemistry, Vol.288, No.5 (2013): 3460-3468. Errami, Y., Naura, A.S., Kim, H., Ju, J., Suzuki, Y., El-Bahrawy, A.H., Ghonim, M.A., Hemeida, R.A., Mansy, M.S., Zhang, J., Xu, M., Smulson, M.E., Hassan Brim, Boulares, A.H.. ...
Apoptotic DNA fragmentation may be a cooperative activity between caspase-activated deoxyribonuclease and the poly(ADP-ribose) polymerase-regulated DNAS1L3, an endoplasmic reticulum-localized endonucleasethat translocates to the nucleus during apoptosis. Journal of Biological Chemistry, Vol.288, No.5 (2013): 3460-3468. Errami, Y., Naura, A.S., Kim, H., Ju, J., Suzuki, Y., El-Bahrawy, A.H., Ghonim, M.A., Hemeida, R.A., Mansy, M.S., Zhang, J., Xu, M., Smulson, M.E., Hassan Brim, Boulares, A.H.. ...
Recognition of misfolded or mutated proteins in the endoplasmic reticulum[edit]. The recognition of misfolded or mutated ... Tyler Mateucci (ERAD) designates a cellular pathway which targets misfolded proteins of the endoplasmic reticulum for ... Endoplasmic-reticulum-associated protein degradation is one of several protein degradation pathways in the ER ... endoplasmic reticulum-associated degradation". Nat. Rev. Mol. Cell Biol. 9 (12): 944-57. doi:10.1038/nrm2546. PMC 2654601 . ...
Endoplasmic reticulum[edit]. 1 Nucleus 2 Nuclear pore 3 Rough endoplasmic reticulum (RER) 4 Smooth endoplasmic reticulum (SER) ... Main article: Endoplasmic reticulum. The endoplasmic reticulum (ER) is a membranous synthesis and transport organelle that is ... The rough endoplasmic reticulum is so named because the cytoplasmic surface is covered with ribosomes, giving it a bumpy ... The nuclear membrane contains a lipid bilayer that encompass the contents of the nucleus.[2] The endoplasmic reticulum (ER) is ...
Endoplasmic reticulum: The endoplasmic reticulum (ER) is a transport network for molecules targeted for certain modifications ... Ribosomes can be found either floating freely or bound to a membrane (the rough endoplasmatic reticulum in eukaryotes, or the ...
ER retention refers to proteins that are retained in the endoplasmic reticulum, or ER, after folding; these are known as ER ... Retrieved from "https://en.wikipedia.org/w/index.php?title=Endoplasmic_reticulum_resident_protein&oldid=864649351" ... and KKXX Retrieval Signals Appended to the Same Reporter Protein Determine Different Trafficking between Endoplasmic Reticulum ...
For this to occur, an N-terminus "signal sequence" of amino acids directs proteins to the endoplasmic reticulum, which inserts ... Cooper GM (2000). "The Endoplasmic Reticulum". The Cell: A Molecular Approach (2nd ed.). Archived from the original on 2017-10- ... and only the outer membrane is continuous with the endoplasmic reticulum (ER) membrane. Like the ER, the outer membrane also ...
"The Endoplasmic Reticulum". The Cell: A Molecular Approach (2nd ed.). Archived from the original on 2017-10-03.. ... and only the outer membrane is continuous with the endoplasmic reticulum (ER) membrane. Like the ER, the outer membrane also ... of amino acids directs proteins to the endoplasmic reticulum, which inserts the proteins into a lipid bilayer. Once inserted, ...
The sarcoplasmic reticulum, a specialized type of smooth endoplasmic reticulum, forms a network around each myofibril of the ... When the action potential reaches the sarcoplasmic reticulum it triggers the release of Ca2+ from the Ca2+ channels. The Ca2+ ... The sarcoplasmic reticulum serves as reservoir for calcium ions, so when an action potential spreads over the T tubule, it ... Very quickly Ca2+ is actively transported back into the sarcoplasmic reticulum, which blocks the interaction between the thin ...
She used a combination of five super-resolution techniques to show that the endoplasmic reticulum is composed of a dense ... "Re-envisioning the endoplasmic reticulum". National Institutes of Health (NIH). 2016-11-07. Retrieved 2018-02-03. Sengupta, ... Using the drug Brefeldin A to perturb membrane trafficking, she showed that membranes cycle between the endoplasmic reticulum ... Their findings may yield new insights for genetic diseases affecting proteins that help shape the endoplasmic reticulum. ...
Along with PPIC, PPIB localizes to the endoplasmic reticulum (ER), where it maintains redox homeostasis. Depletion of these two ... Hasel KW, Glass JR, Godbout M, Sutcliffe JG (1991). "An endoplasmic reticulum-specific cyclophilin". Mol. Cell. Biol. 11 (7): ... Ishikawa Y, Bächinger HP (Nov 2013). "An additional function of the rough endoplasmic reticulum protein complex prolyl 3- ... PPIB localizes to the endoplasmic reticulum (ER) and participates in many biological processes, including mitochondrial ...
... smooth and rough endoplasmic reticulum; sarcoplasmic reticulum; Golgi apparatus; lysosome; mitochondrion (inner and outer ... In eucaryotic cells, new phospholipids are manufactured by enzymes bound to the part of the endoplasmic reticulum membrane that ...
Hotamisligil, Gökhan S (April 2010). "Endoplasmic reticulum stress and atherosclerosis". Nature Medicine. 16 (4): 396-399. doi: ... "Endoplasmic Reticulum Stress Controls M2 Macrophage Differentiation and Foam Cell Formation". Journal of Biological Chemistry. ...
... (3,3′-dihexyloxacarbocyanine iodide) is a fluorescent dye used for the staining of a cell's endoplasmic reticulum, ... DiI 3,3′-Dihexyloxacarbocyanine iodide at Sigma-Aldrich Terasaki M. (1989). "Fluorescent labeling of endoplasmic reticulum". ...
"Endoplasmic Reticulum (Rough and Smooth)". British Society for Cell Biology. Retrieved 12 November 2017. "Golgi Apparatus". ... Various tube- and sheet-like extensions of the nuclear membrane form the endoplasmic reticulum, which is involved in protein ... In 1987 and later papers, Thomas Cavalier-Smith proposed instead that the membranes of the nucleus and endoplasmic reticulum ... It includes the rough endoplasmic reticulum where ribosomes are attached to synthesize proteins, which enter the interior space ...
Oh J, Riek AE, Weng S, Petty M, Kim D, Colonna M, Cella M, Bernal-Mizrachi C (April 2012). "Endoplasmic reticulum stress ... Hotamisligil GS (April 2010). "Endoplasmic reticulum stress and atherosclerosis". Nature Medicine. 16 (4): 396-9. doi:10.1038/ ... Free cholesterol is transported to the endoplasmic reticulum where it is re-esterified by ACAT1 (acyl-CoA: cholesterol ...
Oh J, Riek AE, Weng S, Petty M, Kim D, Colonna M, Cella M, Bernal-Mizrachi C (April 2012). "Endoplasmic reticulum stress ... Hotamisligil GS (April 2010). "Endoplasmic reticulum stress and atherosclerosis". Nature Medicine. 16 (4): 396-9. doi:10.1038/ ...
Smooth and rough endoplasmic reticulum. *Ribosomes. *Golgi bodies. *Microtubules. *(rarely: mitochondria). Hypo-reflective No [ ...
dilation of the endoplasmic reticulum. Fatty change[edit]. The cell has been damaged and is unable to adequately metabolize fat ... these represent distended and pinched-off segments of the endoplasmic reticulum. This pattern of non-lethal injury is sometimes ...
GRAMD1A localizes to the endoplasmic reticulum. Its GRAM domain tethers it to the plasma membrane where it can bind ...
"When hip-hop meets endoplasmic reticulum". Nature India. 2015. doi:10.1038/nindia.2015.52. ISSN 1755-3180. Bengaluru, Nikitha ( ...
Gilmore R, Blobel G, Walter P (November 1982). "Protein translocation across the endoplasmic reticulum. I. Detection in the ... Walter P, Ibrahimi I, Blobel G (November 1981). "Translocation of proteins across the endoplasmic reticulum. I. Signal ... in the endoplasmic reticulum (ER) membrane. This occurs via the interaction and docking of SRP with its cognate SRP receptor ... that recognizes and targets specific proteins to the endoplasmic reticulum in eukaryotes and the plasma membrane in prokaryotes ...
SSCRs promote nuclear mRNA export and the proper localization to the surface of the endoplasmic reticulum. In addition SSCRs ... Gilmore R, Blobel G, Walter P (November 1982). "Protein translocation across the endoplasmic reticulum. I. Detection in the ... Walter P, Ibrahimi I, Blobel G (November 1981). "Translocation of proteins across the endoplasmic reticulum. I. Signal ... These proteins include those that reside either inside certain organelles (the endoplasmic reticulum, Golgi or endosomes), ...
SERP1: Stress-associated endoplasmic reticulum protein 1. *SOX2: transcription factor. *SOX2OT: SOX2 overlapping transcript ...
This enzyme localizes to the endoplasmic reticulum. Alternative splicing may result in other transcript variants, but the ... "Mammalian prenylcysteine carboxyl methyltransferase is in the endoplasmic reticulum". J Biol Chem. 273 (24): 15030-4. doi: ...
Walter P, Ibrahimi I, Blobel G (November 1981). "Translocation of proteins across the endoplasmic reticulum. I. Signal ... Ron, D.; Walter, P. (2007). "Signal integration in the endoplasmic reticulum unfolded protein response". Nature Reviews ... which is one of three known sensors of the folding capacity within the endoplasmic reticulum lumen responsible for initiating a ... "Signal recognition particle contains a 7S RNA essential for protein translocation across the endoplasmic reticulum". Nature. ...
Similarly Matthias Weiss showed that the endoplasmic reticulum displays fractal features. The current understanding is that ... Speckner, Konstantin; Stadler, Lorenz; Weiss, Matthias (July 9, 2018). "Anomalous dynamics of the endoplasmic reticulum network ...
October 2010). "The endoplasmic reticulum stress-C/EBP homologous protein pathway-mediated apoptosis in macrophages contributes ... Li G, Scull C, Ozcan L, Tabas I (December 2010). "NADPH oxidase links endoplasmic reticulum stress, oxidative stress, and PKR ... 2011). "Endoplasmic reticulum stress pathway-mediated apoptosis in macrophages contributes to the survival of Mycobacterium ... 2013). "Endoplasmic reticulum stress contributes to Helicobacter pylori VacA-induced apoptosis". PLOS ONE. 8 (12): e82322. ...
These cells' cytoplasm is rich in tonofilaments and mitochondria; however, they contain few rough endoplasmic reticulum. The ...
RNA translation occurs inside the endoplasmic reticulum. The viral structural proteins S, E and M move along the secretory ...
Proteins that reside in the endoplasmic reticulum (ER), golgi or endosomes also use the co-translational translocation pathway ... Pfeffer SR, Rothman JE (1987-06-01). "Biosynthetic protein transport and sorting by the endoplasmic reticulum and Golgi". ... Walter P, Ibrahimi I, Blobel G (November 1981). "Translocation of proteins across the endoplasmic reticulum. I. Signal ... Rapoport TA (November 2007). "Protein translocation across the eukaryotic endoplasmic reticulum and bacterial plasma membranes ...
HSP47 is expressed in the endoplasmic reticulum. These cells synthesize and secrete type I and type II collagen. The protein ... Rocnik EF, van der Veer E, Cao H, Hegele RA, Pickering JG (October 2002). "Functional linkage between the endoplasmic reticulum ... localizes to the endoplasmic reticulum lumen and binds collagen; thus it is thought to be a molecular chaperone involved in the ...
Abundant rough endoplasmic reticulum combined with a well-developed Golgi apparatus makes plasma cells well-suited for ...
endoplasmic reticulum unfolded protein response. · protein localization to nucleus. · sterol regulatory element binding protein ...
OST is a component of the translocon in the endoplasmic reticulum (ER) membrane. A lipid-linked core-oligosaccharide is ... "Determination of the distance between the oligosaccharyltransferase active site and the endoplasmic reticulum membrane". J. ... assembled at the membrane of the endoplasmic reticulum and transferred to selected asparagine residues of nascent polypeptide ... responsible for cotranslational glycosylation of the nascent polypeptide as it enters the lumen of the endoplasmic reticulum ...
1 Nucleus 2 Nuclear pore 3 Rough endoplasmic reticulum (RER) 4 Smooth endoplasmic reticulum (SER) 5 Ribosome on the rough ER 6 ... The endoplasmic reticulum is in cells that have a nucleus: in eukaryote cells but not in prokaryote cells. It takes these forms ... Rough endoplasmic reticulum (RER), so called because it is studded with ribosomes, and secretes proteins into the cytoplasm. ... Smooth endoplasmic reticulum (SER). Among its functions is the production of proteins and steroids, the maintenance of plasma ...
The sigma-2 receptor agonist PB28 inhibits calcium release from the endoplasmic reticulum of SK-N-SH neuroblastoma cells". Cell ...
... being retained in the endoplasmic reticulum. The serum levels of some of the common genotypes are: PiMM: 100% (normal) PiMS: 80 ...
After entering the host cell, the viral genome is replicated in the rough endoplasmic reticulum (ER) and in the so-called ...
endoplasmic reticulum membrane. • Golgi membrane. • integral component of plasma membrane. • smooth endoplasmic reticulum. • ... rough endoplasmic reticulum. • dendritic shaft. • aggresome. • cell surface. • membrane-bounded organelle. • endoplasmic ... endoplasmic reticulum calcium ion homeostasis. • response to oxidative stress. • autophagosome assembly. • positive regulation ... smooth endoplasmic reticulum calcium ion homeostasis. • synaptic vesicle targeting. • Cajal-Retzius cell differentiation. • ...
endoplasmic reticulum membrane. • часть клеточной мембраны. • ciliary membrane. • система эндомембран. • non-motile cilium. • ...
ER=內質網(Endoplasmic reticulum). DM=连丝微管(Desmotubule). 紅圈處=肌動蛋白. 紫色點=其他蛋白質
The main regulatory mechanism is the sensing of intracellular cholesterol in the endoplasmic reticulum by the protein SREBP ( ... and is either synthesized in the endoplasmic reticulum, or derived from the diet, in which case it is transported by the ...
The virus factory is often enclosed by a membrane derived from the rough endoplasmic reticulum or by cytoskeletal elements. In ... Role of the Intermediate Compartment Between the Endoplasmic Reticulum and the Golgi Stacks". The Journal of Cell Biology. 121 ...
endoplasmic reticulum. • mitochondrial inner membrane. • mitochondrial envelope. • mitochondrial nucleoid. • extracellular ...
In yeast Saccharomyces cerevisiae, squalene epoxidase is localized to both the endoplasmic reticulum and lipid droplets. Only ...
... endoplasmic reticulum into the cytosol. The increased calcium availability binds to the calmodulin subunit and activates ...
... s can be derived from the endoplasmic reticulum and replicate by fission.[13] Peroxisome matrix proteins are ... "Contribution of the endoplasmic reticulum to peroxisome formation". Cell. 122 (1): 85-95. doi:10.1016/j.cell.2005.04.025. PMID ... proteome found homologies between the peroxisomal import machinery and the ERAD pathway in the endoplasmic reticulum,[20][21] ...
Statolith Sedimentation Kinetics and Force Transduction to the Cortical Endoplasmic Reticulum in Gravity-Sensing Arabidopsis ...
"Folding of the human immunodeficiency virus type 1 envelope glycoprotein in the endoplasmic reticulum". Biochimie. 83 (8): 783- ...
BDNF is made in the endoplasmic reticulum and secreted from dense-core vesicles. It binds carboxypeptidase E (CPE), and the ...
... the mRNA of the virus into the amino acid sequences which can be made into proteins in the rough endoplasmic reticulum. This ...
Class II: LDLR is not properly transported from the endoplasmic reticulum to the Golgi apparatus for expression on the cell ...
"The cytoplasmic Hsp70 chaperone machinery subjects misfolded and endoplasmic reticulum import-incompetent proteins to ...
Endoplasmic reticulum. *Golgi apparatus. *Parenthesome. *Autophagosome. *Vesicles *Exosome. *Lysosome. *Endosome. *Phagosome. * ...
The process by which ribosomes in the cytoplasm or endoplasmic reticulum synthesize proteins following the transcription of DNA ... endoplasmic reticulum. A type of organelle found in eukaryotic cells that forms an interconnected network of flattened, ...
These algorithms consider factors such as the likelihood of proteasomal processing, transport into the endoplasmic reticulum, ...
endoplasmic reticulum. • membrane raft. • anchored component of membrane. • extracellular exosome. • cell nucleus. • extrinsic ...
The N-linked glycosylation process occurs in eukaryotes in the lumen of the endoplasmic reticulum and widely in archaea, but ... Secondly, N-linked glycans mediate a critical quality control check point in glycoprotein folding in the endoplasmic reticulum. ... The majority of proteins synthesized in the rough endoplasmic reticulum undergo glycosylation. It is an enzyme-directed site- ... endoplasmic reticulum, cisternae in Golgi apparatus). Therefore, glycosylation is a site-specific modification. ...
Different acyltransferases also have different intracellular distributions, such as the endoplasmic reticulum (ER), the ...
Organelles: (1) nucleolus (2) nucleus (3) ribosome (4) vesicle,(5) rough endoplasmic reticulum (ER), (6) Golgi apparatus, (7) ...
... an intracellular quality control system that detects harmful misfolded proteins in the endoplasmic reticulum and signals the ...
The ER comes in two different morphological forms: smooth endoplasmic reticulum (sER) and rough endoplasmic reticulum (rER). ... Endoplasmic Reticulum The endoplasmic reticulum (ER) is a series of interconnected membranes or flattened sacs adjacent and ... There are two types of endoplasmic reticulum: rough endoplasmic reticulum and smooth endoplasmic reticulum. Rough endoplasmic ... Endoplasmic Reticulum Biology COPYRIGHT 2002 The Gale Group Inc.. Endoplasmic Reticulum. The endoplasmic reticulum (ER) is a ...
Endoplasmic reticulum (ml); endoplasmic reticulum, siateczka plazmatyczna, siateczka endoplazmatyczna, siateczka ... Reticulum endoplasmic (oc); عنڈوپلازمک ریٹیکولم (pnb); endoplasmatiska nätverket (sv); endoplasmatisch reticulum (nl); retículo ... Pliki w kategorii „Endoplasmic reticulum". Poniżej wyświetlono 180 spośród wszystkich 180 plików w tej kategorii. ... Targeted-Mutation-of-the-Mouse-Grp94-Gene-Disrupts-Development-and-Perturbs-Endoplasmic-Reticulum-pone.0010852.s001.ogv 12 s, ...
Calcium-transporting ATPase sarcoplasmic reticulum type, fast-twitch skeletal muscle isoform; Endoplasmic... ... Calcium-transporting ATPase sarcoplasmic reticulum type, fast-twitch skeletal muscle isoform; Endoplasmic reticulum class 1/2 ... Sahoo SK, Shaikh SA, Sopariwala DH, Bal NC, Periasamy M. Sarcolipin protein interaction with sarco(endo)plasmic reticulum Ca2+ ... Zádor E, Kósa M. The neonatal sarcoplasmic/endoplasmic reticulum calcium ATPase (SERCA1b): a neglected pump in scope. Pflugers ...
The endoplasmic reticulum(ER) is the first and usually the largest compartment of the secretory pathway. It is a highly ... Structure and assembly of the endoplasmic reticulum: the synthesis of three major endoplasmic reticulum proteins during ... The endoplasmic reticulum (ER) is the first and usually the largest compartment of the secretory pathway. It is a highly ... Endoplasmic Reticulum Disulfide Bond Protein Disulfide Isomerase Vesicular Stomatitis Virus Disulfide Bond Formation These ...
... smooth endoplasmic reticulum) or studded with ribosomes (rough endoplasmic reticulum), involved in the transport of materials. ... Endoplasmic reticulum definition, a network of tubular membranes within the cytoplasm of the cell, occurring either with a ... endoplasmic reticulum. in Medicine. endoplasmic reticulum. n.. *The membrane network in cytoplasm that is composed of tubules ... The smooth endoplasmic reticulum also transports the products of the rough endoplasmic reticulum to other cell parts, notably ...
... rough endoplasmic reticulum (RER), and smooth endoplasmic reticulum (SER). The endoplasmic reticulum is found in most ... The rough endoplasmic reticulum is especially prominent in cells such as hepatocytes. The smooth endoplasmic reticulum lacks ... Endoplasmic Reticulum Lipid and protein composition of Endoplasmic reticulum in OPM database Animations of the various cell ... there are dilated areas like the sacs of rough endoplasmic reticulum. The network of smooth endoplasmic reticulum allows for an ...
The endoplasmic reticulum is separated into two categories. The parts of the organelle... ... The endoplasmic reticulum was discovered in 1945 by researchers Ernest Fullman, Keith Porter and Albert Claude. ... the endoplasmic reticulum allows ribosomes to translate mRNA from the nucleus into proteins. The endoplasmic reticulum is ... The endoplasmic reticulum was discovered in 1945 by researchers Ernest Fullman, Keith Porter and Albert Claude. The endoplasmic ...
Gene Ontology (GO) annotations for endoplasmic reticulum All GO annotations for Lct (14) ...
The endoplasmic reticulum (ER) is the largest membrane system inside cells and also harbors the richest metabolic activity ... The endoplasmic reticulum (ER) is the largest cellular membrane system and also the most metabolically active organelle ... 1967) Turnover of constituents of the endoplasmic reticulum membranes of rat hepatocytes. J Biol Chem 242:2389-2396. ... 2006) Disruption of endoplasmic reticulum structure and integrity in lipotoxic cell death. J Lipid Res 47:2726-2737. ...
Advanced imaging techniques revealed a more accurate picture of the peripheral endoplasmic reticulum. The findings may yield ... Re-envisioning the endoplasmic reticulum. At a Glance. *Advanced imaging techniques revealed a more accurate picture of how the ... The endoplasmic reticulum (ER) is an organelle that makes and distributes many substances the cell needs, such as proteins, ... The findings may yield new insights for genetic diseases affecting proteins that help shape the endoplasmic reticulum. ...
Induction of endoplasmic reticulum stress-induced beta-cell apoptosis and accumulation of polyubiquitinated proteins by human ... We previously reported that overexpression of hIAPP in transgenic rats triggered endoplasmic reticulum (ER) stress-induced ...
Gene Ontology Term: cortical endoplasmic reticulum. GO ID. GO:0032541 Aspect. Cellular Component. Description. A cortical ... cortical ER, ER-PM peripheral junction, peripheral endoplasmic reticulum, peripheral ER View GO Annotations in other species in ...
ER retention refers to proteins that are retained in the endoplasmic reticulum, or ER, after folding; these are known as ER ... and KKXX Retrieval Signals Appended to the Same Reporter Protein Determine Different Trafficking between Endoplasmic Reticulum ...
Endoplasmic reticulum stress-mediated apoptosis in pancreatic beta-cells.. Oyadomari S1, Araki E, Mori M. ... Recent studies indicated that the endoplasmic reticulum (ER) can sense and transduce apoptotic signals. Various genetic and ...
ERO1A endoplasmic reticulum oxidoreductase 1 alpha [Homo sapiens] ERO1A endoplasmic reticulum oxidoreductase 1 alpha [Homo ... endoplasmic oxidoreductin-1-like protein. endoplasmic reticulum oxidoreductase alpha. oxidoreductin-1-L-alpha. NP_055399.1. *EC ... endoplasmic reticulum oxidoreductase 1 alphaprovided by HGNC. Primary source. HGNC:HGNC:13280 See related. Ensembl: ... Mechanistic Connections between Endoplasmic Reticulum (ER) Redox Control and Mitochondrial Metabolism. Fan Y, et al. Cells, ...
The smooth endoplasmic reticulum, or smooth ER, performs functions in several metabolic processes, including synthesis of ... What is the difference between smooth and rough endoplasmic reticulum?. A: Smooth endoplasmic reticulum is primarily involved ... The smooth endoplasmic reticulum, or smooth ER, performs functions in several metabolic processes, including synthesis of ... A: The smooth endoplasmic reticulum is the organelle responsible for the production of lipids in the cell. This particular ...
Macrophages show endoplasmic reticulum (ER) stress when exposed to lipotoxic signals associated with atherosclerosis, although ... Gökhan Hotamisligil and his colleagues report that reducing endoplasmic reticulum stress in macrophages by targeting the lipid ... The endoplasmic reticulum is the site of cholesterol-induced cytotoxicity in macrophages. Nat. Cell Biol. 5, 781-792 (2003). ... Disruption of endoplasmic reticulum structure and integrity in lipotoxic cell death. J. Lipid Res. 47, 2726-2737 (2006). ...
Endoplasmic Reticulum by Gwyn Reece , This newsletter was created with Smore, an online tool for creating beautiful newsletters ... What are endoplasmic reticulums and what do they do? Endoplasmic reticulums can be rough or smooth. Rough endoplasmic ... Smooth endoplasmic reticulums manufacture and store lipids and steroids. Endoplasmic reticulums are important because your body ... Endoplasmic reticulums are like roads. When lipids, steroids, or proteins are produced, they travel inside smooth or rough ...
endoplasmic reticulum;. tER,. transitional endoplasmic reticulum;. LDM,. low-density microsomes;. PTPase,. protein-tyrosine ... RER, rough endoplasmic reticulum; SER, smooth endoplasmic reticulum. (F) Amount of tER assembly per total membrane ... E) Morphometric studies of the amount of rough endoplasmic reticulum and smooth endoplasmic reticulum membranes in tER networks ... Tyrosine phosphorylation of p97 regulates transitional endoplasmic reticulum assembly in vitro. Christine Lavoie, Eric Chevet, ...
Nonvesicular Lipid Transfer from the Endoplasmic Reticulum. Sima Lev. Sphingolipid Homeostasis in the Endoplasmic Reticulum and ... Disulfide Bond Formation in the Mammalian Endoplasmic Reticulum. Neil J. Bulleid. Endoplasmic Reticulum Structure and ... Lipid Transport between the Endoplasmic Reticulum and Mitochondria. Vid V. Flis and Günther Daum. The Role of the Endoplasmic ... The Endoplasmic Reticulum. Subject Area(s): Developmental Biology; Cell Biology; Proteins and Proteomics; Molecular Biology. ...
1 Nucleus 2 Nuclear pore 3 Rough endoplasmic reticulum (RER) 4 Smooth endoplasmic reticulum (SER) 5 Ribosome on the rough ER 6 ... The endoplasmic reticulum is in cells that have a nucleus: in eukaryote cells but not in prokaryote cells. It takes these forms ... Rough endoplasmic reticulum (RER), so called because it is studded with ribosomes, and secretes proteins into the cytoplasm. ... Smooth endoplasmic reticulum (SER). Among its functions is the production of proteins and steroids, the maintenance of plasma ...
cellular response to endoplasmic reticulum stress, ER stress response, response to ER stress View GO Annotations in other ... Gene Ontology Term: response to endoplasmic reticulum stress. GO ID. GO:0034976 Aspect. Biological Process. Description. Any ... as a result of a stress acting at the endoplasmic reticulum. ER stress usually results from the accumulation of unfolded or ...
Signaling pathways emanating from the endoplasmic reticulum (ER) are involved in apoptosis initiated by stimuli as diverse as ... an important role for BCL-2 proteins at the endoplasmic reticulum is now well established. ... 2005). The endoplasmic reticulum gateway to apoptosis by Bcl-X(L) modulation of the InsP3R. Nat Cell Biol 7: 1021-1028. ... 2002a). Coupling endoplasmic reticulum stress to the cell death program. An Apaf-1-independent intrinsic pathway. J Biol Chem ...
Their analysis led them to the sigma-1 receptor; this protein serves as a chaperone in the endoplasmic reticulum (ER), where it ...
FP3,,,Imperial Cancer Research Fund (ICRF)(UK),UNIVERSITY OF GENEVA(CH),RUPRECHT-KARLS-UNIVERSITAET HEIDELBERG(DE),Universiteit Gent(BE),Institut Curie(FR)
Regulation of sarco(endo)plasmic reticulum Ca2+-ATPase and calsequestrin gene expression in the heart ... The sarcoplasmic reticulum (SR) plays a key role controlling calcium concentration in the cytosol. The SR Ca2+-ATPase (SERCA2) ...
The endoplasmic reticulum (ER) plays a major role in regulating synthesis, folding, and orderly transport of proteins. It is ... The endoplasmic reticulum: folding, calcium homeostasis, signaling, and redox control Antioxid Redox Signal. Sep-Oct 2006;8(9- ... The endoplasmic reticulum (ER) plays a major role in regulating synthesis, folding, and orderly transport of proteins. It is ...
... smooth endoplasmic reticulum, and sarcoplasmic reticulum. Rough endoplasmic reticulum. The surface of the rough endoplasmic ... 1 Nucleus 2 Nuclear pore 3 Rough endoplasmic reticulum (rER) 4 Smooth endoplasmic reticulum (sER) 5 Ribosome on the rough ER 6 ... The majority of endoplasmic reticulum resident proteins are retained in the endoplasmic reticulum through a retention motif. ... Smooth endoplasmic reticulum. The smooth endoplasmic reticulum has functions in several metabolic processes, including ...
... is activated upon the accumulation of misfolded proteins in the endoplasmic reticulum (ER) that are sensed by the binding ... Endoplasmic reticulum stress in liver disease J Hepatol. 2011 Apr;54(4):795-809. doi: 10.1016/j.jhep.2010.11.005. Epub 2010 Nov ... The unfolded protein response (UPR) is activated upon the accumulation of misfolded proteins in the endoplasmic reticulum (ER) ...
Role of endoplasmic reticulum stress in metabolic disease and other disorders. Annu Rev Med 2012;63:317-328pmid:22248326. ... Endoplasmic reticulum stress links obesity, insulin action, and type 2 diabetes. Science 2004;306:457-461pmid:15486293. ... Endoplasmic Reticulum: An Interface Between the Immune System and Metabolism Message Subject (Your Name) has forwarded a page ... Endoplasmic reticulum stress and the inflammatory basis of metabolic disease. Cell 2010;140:900-917pmid:20303879. ...
  • Electron micrograph of hepatocyte cells showing mitochondria (yellow) and endoplasmic reticulum (blue). (britannica.com)
  • Arruda AP, Ketzer LA, Nigro M, Galina A, Carvalho DP, de Meis L. Cold tolerance in hypothyroid rabbits: role of skeletal muscle mitochondria and sarcoplasmic reticulum Ca2+ ATPase isoform 1 heat production. (springer.com)
  • Mitochondria are connected to the endoplasmic reticulum (ER) through specialized protein complexes. (pnas.org)
  • The endoplasmic reticulum (ER) and mitochondria have recently emerged as a paradigm for interorganelle communication ( 1 - 3 ). (pnas.org)
  • Although initially identified as central regulators of apoptosis at the level of mitochondria, an important role for BCL-2 proteins at the endoplasmic reticulum is now well established. (nature.com)
  • Evidence showed that perturbations in the mitochondria-endoplasmic reticulum (ER) network play an important role in the pathogenesis of PD. (frontiersin.org)
  • Transmission Electron Micrograph (TEM) of smooth and rough endoplasmic reticulum and mitochondria in cytoplasm of liver cell. (sciencephoto.com)
  • Endoplasmic reticulum of live bovine pulmonary artery endothelial cells was labeled with ER-Tracker™ Green and mitochondria were visualized with MitoTracker® Red CMXRos . (thermofisher.com)
  • Rough endoplasmic reticulum and ribosomes are involved in protein synthesis, and mitochondria are the site of energy (ATP) production. (varsitytutors.com)
  • The outer ( cytosolic ) face of the rough endoplasmic reticulum is studded with ribosomes that are the sites of protein synthesis . (wikipedia.org)
  • The smooth endoplasmic reticulum lacks ribosomes and functions in lipid manufacture and metabolism, the production of steroid hormones , and detoxification . (wikipedia.org)
  • The surface of the rough endoplasmic reticulum (often abbreviated RER or Rough ER) (also called granular endoplasmic reticulum ) is studded with protein-manufacturing ribosomes giving it a "rough" appearance (hence its name). (wikipedia.org)
  • a network of tubular membranes within the cytoplasm of the cell, occurring either with a smooth surface (smooth endoplasmic reticulum) or studded with ribosomes (rough endoplasmic reticulum) , involved in the transport of materials. (dictionary.com)
  • The rough endoplasmic reticulum is a series of connected flattened sacs that have many ribosomes on their outer surface. (dictionary.com)
  • Due to its close proximity to the nuclear envelope, the endoplasmic reticulum allows ribosomes to translate mRNA from the nucleus into proteins. (reference.com)
  • Rough endoplasmic reticulums look rough because there are ribosomes attached to them. (smore.com)
  • The ribosomes manufacture proteins and store them in the rough endoplasmic reticulums. (smore.com)
  • Rough endoplasmic reticulum ( RER ), so called because it is studded with ribosomes , and secretes proteins into the cytoplasm. (wikipedia.org)
  • So, the rough endoplasmic reticulum, as we mentioned, has ribosomes, which means it's the site of protein synthesis. (khanacademy.org)
  • But, we know that there are also ribosomes that are in the cytoplasm, so, what's the difference between those proteins that are translated in the cytoplasm, and those that are translated in the rough endoplasmic reticulum? (khanacademy.org)
  • So, let's take a look at a protein that was synthesized in the rough endoplasmic reticulum, let's say that this part had a couple of ribosomes and there was a protein made. (khanacademy.org)
  • The surface of the rough endoplasmic reticulum is studded with protein-manufacturing ribosomes giving it a "rough" appearance (hence its name). (wikidoc.org)
  • [3] But it should be noted that these ribosomes are not resident of the endoplasmic reticulum initially. (wikidoc.org)
  • endoplasmic reticulum an ultramicroscopic organelle of nearly all higher plant and animal cells, consisting of a system of membrane-bound cavities in the cytoplasm, occurring in two types: granular or rough-surfaced, bearing large numbers of ribosomes on its outer surface, and agranular or smooth-surfaced. (thefreedictionary.com)
  • Ribosomes, the endoplasmic reticulum, and the Golgi apparatus are all organelles. (enotes.com)
  • How do the functions of ribosomes, the Golgi body, and the endoplasmic reticulum relate to one. (enotes.com)
  • In large part, the misfolding of proteins takes place during synthesis on free ribosomes in the cytoplasm or on endoplasmic reticulum ribosomes. (ahajournals.org)
  • The main reason why the rough endoplasmic reticulum is referred as 'rough' is due to the ribosomes that it contains. (plant-biology.com)
  • The ribosomes in the rough ER perform their tasks and create proteins that will be sent to the rough endoplasmic reticulum to undergo advance processing. (plant-biology.com)
  • All protein synthesis occurs in the ribosomes, some of which are on the endoplasmic reticulum (rough ER), and some are floating in the cytoplasm. (varsitytutors.com)
  • Protein synthesis requires the action of ribosomes, which can be found in the cytosol or embedded in the membrane of the rough endoplasmic reticulum. (varsitytutors.com)
  • This means that organelle A has more proteins than organelle B. Remember that rough endoplasmic reticulum (rough ER) is termed 'rough' because it contains ribosomes on its surface. (varsitytutors.com)
  • The sarcoplasmic reticulum is a specialized type of smooth ER that regulates the calcium ion concentration in the cytoplasm of striated muscle cells. (britannica.com)
  • Finally, the SER in muscle cells, known as the sarcoplasmic reticulum , sequesters calcium ions from the cytoplasm. (britannica.com)
  • The Ca2+ is released from the sarcoplasmic reticulum by ryanodine receptor and taken back to the SR by SERCA pumps. (springer.com)
  • Adult forms of the Ca2+ATPase of sarcoplasmic reticulum. (springer.com)
  • Purification and properties of an adenosine triphosphatase from sarcoplasmic reticulum. (springer.com)
  • Amino-acid sequence of a Ca2+ + Mg2+-dependent ATPase from rabbit muscle sarcoplasmic reticulum, deduced from its complementary DNA sequence. (springer.com)
  • Mutations in the gene-encoding SERCA1, the fast-twitch skeletal muscle sarcoplasmic reticulum Ca2+ ATPase, are associated with Brody disease. (springer.com)
  • Crystal structure of sarcoplasmic reticulum Ca2+-ATPase (SERCA) from bovine muscle. (springer.com)
  • Toyoshima C. How Ca2+-ATPase pumps ions across the sarcoplasmic reticulum membrane. (springer.com)
  • Toyoshima C, Nakasako M, Nomura H, Ogawa H. Crystal structure of the calcium pump of sarcoplasmic reticulum at 2.6 A resolution. (springer.com)
  • Similar to the ER is the sarcoplasmic reticulum ( SR ) found only in muscle cells. (wikipedia.org)
  • The sarcoplasmic reticulum (SR) plays a key role controlling calcium concentration in the cytosol. (ingentaconnect.com)
  • The three varieties are called rough endoplasmic reticulum , smooth endoplasmic reticulum , and sarcoplasmic reticulum . (wikidoc.org)
  • sarcoplasmic reticulum a form of agranular reticulum in the sarcoplasm of striated muscle, comprising a system of smooth-surfaced tubules surrounding each myofibril. (thefreedictionary.com)
  • Key regulator of striated muscle performance by acting as the major Ca(2+) ATPase responsible for the reuptake of cytosolic Ca(2+) into the sarcoplasmic reticulum. (rcsb.org)
  • Catalyzes the hydrolysis of ATP coupled with the translocation of calcium from the cytosol to the sarcoplasmic reticulum lumen (By similarity). (rcsb.org)
  • The endoplasmic reticulum (ER) is a system of membranous cisternae (flattened sacs) extending throughout the cytoplasm . (britannica.com)
  • That are made in the cytoplasm and those that are synthesized in the rough endoplasmic reticulum. (khanacademy.org)
  • But, you might be thinking, how does a protein, quote, unquote, know that it's supposed to be following the secretory pathway, and therefore, that it should be synthesized in the rough endoplasmic reticulum as opposed to the cytoplasm? (khanacademy.org)
  • Here, we examined the expression of genes associated with Ca 2+ channels using a model of Txn suppression in cardiomyocyte cultures (siRNA and Txn inhibitor) and report that Txn knockdown can cause Ca 2+ overload in the myocardial cytoplasm and release of endoplasmic reticulum (ER) Ca 2+ , which induces ER stress. (rsc.org)
  • The functions of the endoplasmic reticulum can be summarized as the synthesis and export of proteins and membrane lipids, but varies between ER and cell type and cell function. (wikipedia.org)
  • The smooth endoplasmic reticulum is tubular in form and is involved in the synthesis of phospholipids, the main lipids in cell membranes. (dictionary.com)
  • The rough portion of the endoplasmic reticulum manages the synthesis of proteins and packages them into vesicles for transport and further modification by the golgi apparatus. (reference.com)
  • The endoplasmic reticulum (ER) is the largest membrane system inside cells and also harbors the richest metabolic activity including lipid synthesis. (pnas.org)
  • The endoplasmic reticulum (ER) is the largest cellular membrane system and also the most metabolically active organelle responsible for lipid synthesis. (pnas.org)
  • The smooth endoplasmic reticulum, or smooth ER, performs functions in several metabolic processes, including synthesis of steroids, lipids and phospholipids, as well as the metabolism of carbohydrates, elimination of drugs from the system and attachment of receptors to cell membrane proteins. (reference.com)
  • Okay, let's go back to the protein synthesis that happens in the rough endoplasmic reticulum. (khanacademy.org)
  • The smooth endoplasmic reticulum has functions in several metabolic processes, including synthesis of lipids, metabolism of carbohydrates and calcium concentration, drug detoxification, and attachment of receptors on cell membrane proteins. (wikidoc.org)
  • IDIBELL researchers have been able to relate the activation of these membrane receptors to the endoplasmic reticulum, a cellular organelle involved in protein synthesis and lipid metabolism, as well as intracellular transport. (news-medical.net)
  • The endoplasmic reticulum (ER) coordinates the synthesis, folding, and sorting of proteins for retention in the cell or for entry into the secretory pathway. (diabetesjournals.org)
  • The high rate of protein synthesis in MM cells stresses the endoplasmic reticulum (ER), where such secreted proteins are produced. (sciencemag.org)
  • SHIODA, M. (1986), DNA synthesis in vitro with an endoplasmic-reticulum-DNA-polymerase complex from unfertilized sea urchin eggs. (wiley.com)
  • The rough endoplasmic reticulum forms a branched reticulum that is expanding as the cell becomes more active in the synthesis of proteins. (plant-biology.com)
  • Since they are lipids, steroids are synthesized in the smooth endoplasmic reticulum, the site of lipid synthesis. (varsitytutors.com)
  • The endoplasmic reticulum (ER) is the main site for the synthesis, processing and transport of the majority of intracellular, cell surface and extracellular proteins. (spandidos-publications.com)
  • The endoplasmic reticulum (ER ) is a type of organelle found in eukaryotic cells that forms an interconnected network of flattened, membrane-enclosed sacs or tube-like structures known as cisternae . (wikipedia.org)
  • In the late 1940s and early 1950s, Porter and colleagues Helen P. Thompson and Frances Kallman introduced the term endoplasmic reticulum to describe the organelle. (britannica.com)
  • It is a type of organelle made up of two subunits - rough endoplasmic reticulum (RER), and smooth endoplasmic reticulum (SER). (wikipedia.org)
  • The endoplasmic reticulum (ER) is an organelle that makes and distributes many substances the cell needs, such as proteins, lipids, and sugars. (nih.gov)
  • The endoplasmic reticulum (ER), a membrane compartment located near the nucleus, is the organelle where polypeptides, which will become secretory proteins or membrane proteins, are synthesized from mRNA and become mature proteins after undergoing folding, assembly, glycosylation, disulfide bonding, and posttranslational modifications [ 1 ]. (hindawi.com)
  • Both the smooth and rough endoplasmic reticulum form an organelle in eukaryotic organisms creating a network of tubes or sacs called cisternae, but it is the smooth endoplasmic reticulum that helps the body eliminate a number of toxins. (reference.com)
  • The smooth endoplasmic reticulum is the organelle responsible for the production of lipids in the cell. (reference.com)
  • Endoplasmic reticulum ( ER ) is a cellular organelle . (wikipedia.org)
  • Voiceover] The endoplasmic reticulum is an organelle in the cell that butts off of the nucleus. (khanacademy.org)
  • The Golgi apparatus is an organelle that's found near the endoplasmic reticulum. (khanacademy.org)
  • The endoplasmic reticulum or ER is an organelle found in all eukaryotic cells that is an interconnected network of tubules , vesicles and cisternae . (wikidoc.org)
  • Endoplasmic reticulum (ER) is a busy cell organelle that participates in many important cellular tasks. (diabetesjournals.org)
  • THE endoplasmic reticulum (ER) is a central organelle in the biogenesis of secretory and membrane proteins. (genetics.org)
  • A wound-inducible organelle derived from endoplasmic reticulum : a plant strategy against environmental stress? (nii.ac.jp)
  • The endoplasmic reticulum ( ER ) is a teep o organelle in the cells o eukaryotic organisms that forms an interconnectit network o flattened, membrane-enclosed sacs or tubes kent as cisternae . (wikipedia.org)
  • One of the organelle-specific protein quality control systems resides in the endoplasmic reticulum (ER), and is responsive to stresses that lead to the accumulation of misfolded proteins in the lumen of the rough ER. (ahajournals.org)
  • The endoplasmic reticulum (ER) has long been considered an exceedingly important and complex cellular organelle in eukaryotes (like you). (aps.org)
  • We cannot draw any conclusions about organelle B, since most organelles contain fewer amino acids and proteins than the rough endoplasmic reticulum. (varsitytutors.com)
  • SERCA1 truncated proteins unable to pump calcium reduce the endoplasmic reticulum calcium concentration and induce apoptosis. (springer.com)
  • Zádor E, Kósa M. The neonatal sarcoplasmic/endoplasmic reticulum calcium ATPase (SERCA1b): a neglected pump in scope. (springer.com)
  • Smooth endoplasmic reticulum is the site of the breakdown of toxins and carcinogens in the liver, the conversion of cholesterol into steroids in the gonads and adrenal glands, and the release of calcium ions in the muscles, causing muscle contraction. (dictionary.com)
  • The smooth endoplasmic reticulum is known for its storage of calcium ions in muscle cells . (wikidoc.org)
  • Transports calcium ions from the cytosol into the sarcoplasmic/endoplasmic reticulum lumen. (uniprot.org)
  • Another agent, thapsigargin, also induces ER stress via inhibition of the sarcoplasmic/endoplasmic Ca 2+ -ATPase, which disrupts ER calcium homeostasis ( 6 ). (aacrjournals.org)
  • [2] [3] With electron microscopy , the lacy membranes of the endoplasmic reticulum were first seen in 1945 by Keith R. Porter , Albert Claude , Brody Meskers and Ernest F. Fullam. (wikipedia.org)
  • [4] Later, the word " reticulum ", which means "network", was applied by Porter in 1953 to describe this fabric of membranes. (wikipedia.org)
  • The general structure of the endoplasmic reticulum is a network of membranes called cisternae . (wikipedia.org)
  • The endoplasmic reticulum (ER) is a series of interconnected membranes or flattened sacs adjacent and connected to the nuclear membrane. (encyclopedia.com)
  • The second method of transport out of the endoplasmic reticulum involves areas called membrane contact sites, where the membranes of the endoplasmic reticulum and other organelles are held closely together, allowing the transfer of lipids and other small molecules. (wikipedia.org)
  • The endoplasmic reticulum (ER) is an extensive network of membranes that folds, modifies, and transports proteins in eukaryotic cells. (cshlpress.com)
  • The lacey membranes of the endoplasmic reticulum were first seen in 1945 by scientists using an electron microscope . (wikipedia.org)
  • The lacey membranes of the endoplasmic reticulum were first seen by Keith R. Porter, Albert Claude , and Ernest F. Fullam in 1945. (wikidoc.org)
  • The network of folded membranes that comprises the endoplasmic reticulum (ER) in all eukaryotic cells constitutes greater than half of the total membrane content in the average animal cell. (thermofisher.com)
  • Its function involves the creation of two protein types: one is the type that toughens and is embedded into the reticulum membrane and other type is the membranes that are water-soluble, which after creation at ribosomal site, passes through the membrane and into the lumen. (plant-biology.com)
  • The Arabidopsis ( Arabidopsis thaliana ) genome encodes homologs of the Guided Entry of Tail (GET)-anchored protein system for the posttranslational insertion of tail-anchored ( TA ) proteins into endoplasmic reticulum (ER) membranes. (plantphysiol.org)
  • There are two general systems for targeting proteins to endoplasmic reticulum (ER) membranes: one is cotranslational and the other is posttranslational. (plantphysiol.org)
  • One of these structures is the endoplasmic reticulum, which is a network of tubular membranes that runs lengthwise along the axon. (elifesciences.org)
  • Within TRAIN-ERs, the goal of our research group was to study the role of endoplasmic reticulum stress signals in starvation, and we have shown that it is essential,' says Muñoz-Pinedo. (news-medical.net)
  • Mammalian transcription factor ATF6 is synthesized as a transmembrane protein and activated by proteolysis in response to endoplasmic reticulum stress. (semanticscholar.org)
  • ARTICLE{Haze99mammaliantranscription, author = {Kyosuke Haze and Hiderou Yoshida and Hideki Yanagi and Takashi Yura and Kazutoshi Mori}, title = {Mammalian transcription factor ATF6 is synthesized as a transmembrane protein and activated by proteolysis in response to endoplasmic reticulum stress}, journal = {Mol. (psu.edu)
  • Notice that the space in the nuclear envelope is continuous with the lumen, or space, of the endoplasmic reticulum. (khanacademy.org)
  • They are located in the lumen of the endoplasmic reticulum (ER). (wikipedia.org)
  • Micrograph of rough endoplasmic reticulum network around the nucleus (shown in lower right-hand side of the picture). (wikipedia.org)
  • Micrograph o rough endoplasmic reticulum network aroond the nucleus (shawn in lawer richt-haund side o the pictur). (wikipedia.org)
  • Homocysteine causes vascular endothelial dysfunction by disrupting endoplasmic reticulum redox homeostasis. (sigmaaldrich.com)
  • However, little is known about the role of endoplasmic reticulum (ER) redox homeostasis in HHcy-induced endothelial dysfunction. (sigmaaldrich.com)
  • Disruptions in Ca 2+ homeostasis, inhibition of protein glycosylation, and accumulation of misfolded proteins can all challenge the function of the endoplasmic reticulum (ER)-Golgi network, resulting in ER stress ( 4 ). (aacrjournals.org)
  • Xi-Qin Deng , Associate Professor of Cell Biology, and the Joanne I Moore Professor of Pharmacology at University of Oklahoma Health Sciences Center will be delivering a seminar on "cGMP/PKG signaling regulation of endoplasmic reticulum homeostasis in CNG channel deficiency" on Wednesday, January 24th at 12:00 Noon in the Moran Eye Center auditorium. (utah.edu)
  • The function of the endoplasmic reticulum can vary greatly with cell type, and even within the same cell it can have different functions depending on whether it is rough or smooth. (dictionary.com)
  • Specifically, Ca2+ is required for the function of the endoplasmic reticulum in which proteins, including immuno. (bioportfolio.com)
  • The functions of the endoplasmic reticulum vary greatly depending on the exact type of endoplasmic reticulum and the type of cell in which it resides. (wikidoc.org)
  • In this lesson, you will learn about the structure and functions of the endoplasmic reticulum. (generationq.net)
  • Integral membrane proteins from the endoplasmic reticulum induce the development of tubular structures in vitro by forming oligomers in the plane of the membrane. (sciencemag.org)
  • The findings may yield new insights for genetic diseases affecting proteins that help shape the endoplasmic reticulum. (nih.gov)
  • It is known that spastic paraplegias are sometimes caused by mutations affecting proteins that help to build and shape the endoplasmic reticulum, for example, the proteins of the reticulon and REEP families. (elifesciences.org)
  • endoplasmic reticulum Endoplasmic reticulum, a continuous membrane system in eukaryotic cells that plays an important role in the biosynthesis, processing, and transport of proteins and lipids. (britannica.com)
  • The smooth endoplasmic reticulum synthesizes and stores lipids in animal cells. (reference.com)
  • Smooth endoplasmic reticulum is primarily involved with the production of lipids and removing drugs or poisons from the body, according to the British Soci. (reference.com)
  • When lipids, steroids, or proteins are produced, they travel inside smooth or rough endoplasmic reticulums until they reach the cell membrane so that they can be delivered to other parts of the body. (smore.com)
  • Smooth endoplasmic reticulums manufacture and store lipids and steroids. (smore.com)
  • Endoplasmic reticulums are important because your body needs protein to build tissue and lipids to store energy. (smore.com)
  • In addition to synthesizing lipids, the smooth endoplasmic reticulum plays an important role in detoxification of chemicals. (varsitytutors.com)
  • The Endoplasmic Reticulum and Golgi Body: What's the Difference? (news-medical.net)
  • The Golgi body (or Golgi complex, apparatus), and Endoplasmic reticulum (ER) are both organelles found in the majority of eukaryotic cells. (news-medical.net)
  • Endoplasmic reticulum (ER) is a dynamic, tubular intracellular network implicated in a variety of cellular functions. (europa.eu)
  • Proteins can be packaged and transported through the cell by the smooth endoplasmic reticulum, as can other cellular components and materials. (varsitytutors.com)
  • The endoplasmic reticulum (ER) is considered a key player in the response to cellular stress and protein overload of the ER. (asnjournals.org)
  • Endoplasmic reticulum stress-mediated apoptosis in pancreatic beta-cells. (nih.gov)
  • We have shown previously that bortezomib has activity in pancreatic cancer models and that the drug induces endoplasmic reticulum (ER) stress but also suppresses the unfolded protein response (UPR). (aacrjournals.org)
  • Porcine circovirus type 2 ORF5 protein induces endoplasmic reticulum stress and unfolded protein response in porcine alveolar macrophages. (bioportfolio.com)
  • Advanced imaging techniques revealed a more accurate picture of how the peripheral endoplasmic reticulum is structured. (nih.gov)
  • The endoplasmic reticulum can be continuous in places with the membrane of the cell nucleus. (dictionary.com)
  • The rough endoplasmic reticulum is connected with the outer envelope of the nucleus of the cell. (plant-biology.com)
  • Signaling pathways emanating from the endoplasmic reticulum (ER) are involved in apoptosis initiated by stimuli as diverse as ER stress, oncogene expression, death receptor (DR) ligation and oxidative stress, and the BCL-2 family is almost invariably implicated in the regulation of these pathways. (nature.com)
  • Regulation of sarco(endo)plasmic reticulum Ca2+-ATPase and calseq. (ingentaconnect.com)
  • Linking of autophagy to ubiquitin-proteasome system is important for the regulation of endoplasmic reticulum stress and cell viability. (semanticscholar.org)
  • In this study, we incubated bovine aortic endothelial cells (BAECs) with ox-LDL (100 µg/ml) in order to induce endoplasmic reticulum (ER) stress and to investigate the regulation of endothelial nitric oxide synthase (eNOS). (spandidos-publications.com)
  • The endoplasmic reticulum occurs in most types of eukaryotic cells, but is absent from red blood cells and spermatozoa . (wikipedia.org)
  • All eukaryotic cells contain an endoplasmic reticulum (ER). (britannica.com)
  • The endoplasmic reticulum (ER) is, in essence, the transportation system of the eukaryotic cell, and has many other important functions such as protein folding. (wikipedia.org)
  • The endoplasmic reticulum is found in most eukaryotic cells and forms an interconnected network of flattened, membrane-enclosed sacs known as cisternae (in the RER), and tubular structures in the SER. (wikipedia.org)
  • In the tumor microenvironment hypoxia and nutrient deprived states can induce endoplasmic reticulum (ER) stress. (mdpi.com)
  • Sahoo SK, Shaikh SA, Sopariwala DH, Bal NC, Periasamy M. Sarcolipin protein interaction with sarco(endo)plasmic reticulum Ca2+ ATPase (SERCA) is distinct from phospholamban protein, and only sarcolipin can promote uncoupling of the SERCA pump. (springer.com)
  • Three novel sarco/endoplasmic reticulum Ca2+-ATPase (SERCA) 3 isoforms. (uniprot.org)
  • Although this priming effect is thought to increase the ER Ca 2+ content by activating the sarcoplasmic/endoplasmic reticulum Ca 2+ -ATPase (SERCA), the actual Ca 2+ concentration of the ER has not been directly examined, due in part to the lack of appropriate technologies for monitoring ER Ca 2+ dynamics. (jneurosci.org)
  • Physiological or pathological processes that disturb protein folding in the endoplasmic reticulum cause ER stress and activate a set of signaling pathways termed the Unfolded Protein Response (UPR). (hindawi.com)
  • The protein folding capacity of the endoplasmic reticulum (ER) is tightly regulated by a network of signaling pathways, known as the unfolded protein response (UPR). (bioportfolio.com)
  • The endoplasmic reticulum (ER) plays crucial roles in intracellular Ca 2+ signaling, serving as both a source and sink of Ca 2+ , and regulating a variety of physiological and pathophysiological events in neurons in the brain. (jneurosci.org)
  • The membrane around the smooth endoplasmic reticulum can be used to create intracellular vesicles. (varsitytutors.com)
  • The endoplasmic reticulum (ER) is an extensive network of flattened, membrane-enclosed tubes or sacs that extends throughout the cytosol [ 1 ]. (intechopen.com)
  • The rough endoplasmic reticulum is especially prominent in cells such as hepatocytes . (wikipedia.org)
  • The endoplasmic reticulum is not found in red blood cells, or spermatozoa. (wikipedia.org)
  • The smooth endoplasmic reticulum is especially abundant in mammalian liver and gonad cells. (wikipedia.org)
  • We previously reported that overexpression of hIAPP in transgenic rats triggered endoplasmic reticulum (ER) stress-induced apoptosis in beta-cells. (mendeley.com)
  • In some cells there are dilated areas like the sacs of rough endoplasmic reticulum. (wikidoc.org)
  • The high activity of those cells is revealed through the abundant presence of endoplasmic reticulum from the moment the oocyte begins the secondary growth phase. (thefreedictionary.com)
  • Tseng, S.-H. HDAC Inhibitors and RECK Modulate Endoplasmic Reticulum Stress in Tumor Cells. (mdpi.com)
  • Chen Y, Tsai Y-H, Tseng S-H. HDAC Inhibitors and RECK Modulate Endoplasmic Reticulum Stress in Tumor Cells. (mdpi.com)
  • 1. It was discovered by Porter (1945) as fine recticulum in endoplasm of cells and named as endoplasmic reticulum (E.R. (generationq.net)
  • Previous studies have demonstrated that endoplasmic reticulum (ER) stress induced by ox-LDL in human vascular cells modulates the balance between survival and apoptosis induced by ox-LDL ( 10 - 12 ). (spandidos-publications.com)
  • Cells in the liver, called hepatocytes, have particularly large smooth endoplasmic reticulum regions, allowing them to be especially efficient at clearly toxins from the body. (varsitytutors.com)
  • Endoplasmic reticulum stress in beta cells: latent mechanism of secondary sulfonylurea failure in type 2 diabetes? (biomedsearch.com)
  • The unfolded protein response (UPR) is a homeostatic pathway that regulates endoplasmic reticulum (ER) membrane structure and secretory function. (generationq.net)
  • Induction of endoplasmic reticulum stress-induced beta-cell apoptosis and accumulation of polyubiquitinated proteins by human islet amyloid polypeptide. (mendeley.com)
  • The endoplasmic reticulum (ER) is the first and usually the largest compartment of the secretory pathway. (springer.com)
  • 2014. "Thioredoxin-interacting protein regulates protein disulfide isomerases and endoplasmic reticulum stress. (harvard.edu)
  • The quantity of both rough and smooth endoplasmic reticulum in a cell can slowly interchange from one type to the other, depending on the changing metabolic activities of the cell. (wikipedia.org)
  • Adipocyte stress: the endoplasmic reticulum and metabolic disease. (nature.com)
  • The endoplasmic reticulum is also the site of many other cell metabolic reactions. (thefreedictionary.com)
  • Endoplasmic reticulum (ER) stress is emerging recently as a common feature in the pathology of numerous diseases including cancer, neurodegenerative disorders, metabolic syndromes and inflammatory diseases, affecting millions of patients annually worldwide and assuming a huge economic burden for the health sector. (news-medical.net)
  • Various conditions play a role in the pathogenesis of pancreatic beta cell dysfunction and are correlated with endoplasmic reticulum (ER) stress. (hindawi.com)
  • E19 blocked the presentation of vaccinia and influenza virus proteins to CTLs in a MHC class I allele-specific manner identical to its inhibition of MHC class I transport from the endoplasmic reticulum. (sciencemag.org)
  • Inhibition of endoplasmic reticulum stress protected DOCA-salt hypertension-induced vascular dysfunction. (bioportfolio.com)
  • The highly convoluted and labyrinthine structure of the ER led to its description in 1945 as a "lace-like reticulum" by cell biologists Keith Porter, Albert Claude , and Ernest Fullman, who produced the first electron micrograph of a cell. (britannica.com)
  • The endoplasmic reticulum was discovered in 1945 by researchers Ernest Fullman, Keith Porter and Albert Claude. (reference.com)
  • The general structure of the endoplasmic reticulum is an extensive membrane network of cisternae (sac-like structures) held together by the cytoskeleton . (wikidoc.org)
  • There are instances wherein the reticulum branches out and the cisternae dilate and forms large sacs that fill the cell. (plant-biology.com)
  • The links between systemic inflammation, endothelial dysfunction and endoplasmic reticulum (ER) stress in pre-clinical models make it an interesting potential therapeutic target, but there. (bioportfolio.com)
  • Mounting evidence suggests that an imbalance of the oxidant-antioxidant defence system is strongly correlated with depression and the dysfunction of the endoplasmic reticulum (ER) is strongly related to the oxidative stress. (rsc.org)
  • Using high-magnification electron microscopy confirmed these findings, and showed that the tubules of the endoplasmic reticulum in mutant axons were larger, but fewer. (elifesciences.org)
  • Wikimedia Commons has media related to Endoplasmic reticulum . (wikipedia.org)
  • The ER comes in two different morphological forms: smooth endoplasmic reticulum (sER) and rough endoplasmic reticulum (rER). (encyclopedia.com)
  • The endoplasmic reticulum can be classified in two functionally distinct forms, the smooth endoplasmic reticulum (SER) and the rough endoplasmic reticulum (RER). (britannica.com)
  • The smooth endoplasmic reticulum also transports the products of the rough endoplasmic reticulum to other cell parts, notably the Golgi apparatus. (dictionary.com)
  • What does the smooth endoplasmic reticulum do? (reference.com)
  • Let's start with the smooth endoplasmic reticulum first. (khanacademy.org)
  • The smooth endoplasmic reticulum also metabolizes carbohydrates. (khanacademy.org)
  • Smooth endoplasmic reticulum is found in a variety of cell types (both animal and plant) and it serves different functions in each. (wikidoc.org)
  • The network of smooth endoplasmic reticulum allows increased surface area for the action or storage of key enzymes and the products of these enzymes. (wikidoc.org)
  • Smooth Endoplasmic Reticulum use and functions Golgi Apparatus use and functions Rough. (enotes.com)
  • There are two types of endoplasmic reticulum: the rough and smooth endoplasmic reticulum . (plant-biology.com)
  • Detoxification of harmful substances is carried out by the smooth endoplasmic reticulum. (varsitytutors.com)
  • The smooth endoplasmic reticulum has a variety of functions, one of which involves the detoxification of drugs and pollutants found in the body. (varsitytutors.com)
  • Enzymes found in the smooth endoplasmic reticulum allow it to break down harmful drugs and toxins. (varsitytutors.com)
  • Which of the following is not a function of the smooth endoplasmic reticulum? (varsitytutors.com)
  • The smooth endoplasmic reticulum has a variety of functions. (varsitytutors.com)
  • The smooth endoplasmic reticulum is also responsible for using these vesicles to interface with the plasma membrane, synthesizing phospholipids to repair and grow the membrane surface area. (varsitytutors.com)
  • The smooth endoplasmic reticulum also contains enzymes responsible for degrading inorganic toxins, such as alcohol and drugs. (varsitytutors.com)
  • This detoxification process occurs in the liver, which contains an abundance of smooth endoplasmic reticulum. (varsitytutors.com)
  • Remember that smooth endoplasmic reticulum also plays a role in detoxification of harmful chemicals. (varsitytutors.com)
  • [2] The endoplasmic reticulum is part of the endomembrane system . (wikidoc.org)