Membrane Microdomains: Detergent-insoluble CELL MEMBRANE components. They are enriched in SPHINGOLIPIDS and CHOLESTEROL and clustered with glycosyl-phosphatidylinositol (GPI)-anchored proteins.Glycolipids: Any compound containing one or more monosaccharide residues bound by a glycosidic linkage to a hydrophobic moiety such as an acylglycerol (see GLYCERIDES), a sphingoid, a ceramide (CERAMIDES) (N-acylsphingoid) or a prenyl phosphate. (From IUPAC's webpage)beta-Cyclodextrins: Cyclic GLUCANS consisting of seven (7) glucopyranose units linked by 1,4-glycosidic bonds.Cell Membrane: The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.Detergents: Purifying or cleansing agents, usually salts of long-chain aliphatic bases or acids, that exert cleansing (oil-dissolving) and antimicrobial effects through a surface action that depends on possessing both hydrophilic and hydrophobic properties.Membrane Lipids: Lipids, predominantly phospholipids, cholesterol and small amounts of glycolipids found in membranes including cellular and intracellular membranes. These lipids may be arranged in bilayers in the membranes with integral proteins between the layers and peripheral proteins attached to the outside. Membrane lipids are required for active transport, several enzymatic activities and membrane formation.Caveolae: Endocytic/exocytic CELL MEMBRANE STRUCTURES rich in glycosphingolipids, cholesterol, and lipid-anchored membrane proteins that function in ENDOCYTOSIS (potocytosis), transcytosis, and SIGNAL TRANSDUCTION. Caveolae assume various shapes from open pits to closed vesicles. Caveolar coats are composed of CAVEOLINS.Caveolin 1: A tyrosine phosphoprotein that plays an essential role in CAVEOLAE formation. It binds CHOLESTEROL and is involved in LIPIDS transport, membrane traffic, and SIGNAL TRANSDUCTION.Caveolins: The main structural proteins of CAVEOLAE. Several distinct genes for caveolins have been identified.Cyclodextrins: A homologous group of cyclic GLUCANS consisting of alpha-1,4 bound glucose units obtained by the action of cyclodextrin glucanotransferase on starch or similar substrates. The enzyme is produced by certain species of Bacillus. Cyclodextrins form inclusion complexes with a wide variety of substances.Octoxynol: Nonionic surfactant mixtures varying in the number of repeating ethoxy (oxy-1,2-ethanediyl) groups. They are used as detergents, emulsifiers, wetting agents, defoaming agents, etc. Octoxynol-9, the compound with 9 repeating ethoxy groups, is a spermatocide.Cholesterol: The principal sterol of all higher animals, distributed in body tissues, especially the brain and spinal cord, and in animal fats and oils.Glycosphingolipids: Lipids containing at least one monosaccharide residue and either a sphingoid or a ceramide (CERAMIDES). They are subdivided into NEUTRAL GLYCOSPHINGOLIPIDS comprising monoglycosyl- and oligoglycosylsphingoids and monoglycosyl- and oligoglycosylceramides; and ACIDIC GLYCOSPHINGOLIPIDS which comprises sialosylglycosylsphingolipids (GANGLIOSIDES); SULFOGLYCOSPHINGOLIPIDS (formerly known as sulfatides), glycuronoglycosphingolipids, and phospho- and phosphonoglycosphingolipids. (From IUPAC's webpage)G(M1) Ganglioside: A specific monosialoganglioside that accumulates abnormally within the nervous system due to a deficiency of GM1-b-galactosidase, resulting in GM1 gangliosidosis.Membranes: Thin layers of tissue which cover parts of the body, separate adjacent cavities, or connect adjacent structures.Protein Transport: 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.Signal Transduction: 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.Glycosylphosphatidylinositols: Compounds containing carbohydrate or glycosyl groups linked to phosphatidylinositols. They anchor GPI-LINKED PROTEINS or polysaccharides to cell membranes.Intracellular Membranes: 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.Cell Line: Established cell cultures that have the potential to propagate indefinitely.G(M3) Ganglioside: A ganglioside present in abnormally large amounts in the brain and liver due to a deficient biosynthetic enzyme, G(M3):UDP-N-acetylgalactosaminyltransferase. Deficiency of this enzyme prevents the formation of G(M2) ganglioside from G(M3) ganglioside and is the cause of an anabolic sphingolipidosis.Sphingolipids: A class of membrane lipids that have a polar head and two nonpolar tails. They are composed of one molecule of the long-chain amino alcohol sphingosine (4-sphingenine) or one of its derivatives, one molecule of a long-chain acid, a polar head alcohol and sometimes phosphoric acid in diester linkage at the polar head group. (Lehninger et al, Principles of Biochemistry, 2nd ed)Membrane Proteins: 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.Filipin: A complex of polyene antibiotics obtained from Streptomyces filipinensis. Filipin III alters membrane function by interfering with membrane sterols, inhibits mitochondrial respiration, and is proposed as an antifungal agent. Filipins I, II, and IV are less important.Membrane Potentials: The voltage differences across a membrane. For cellular membranes they are computed by subtracting the voltage measured outside the membrane from the voltage measured inside the membrane. They result from differences of inside versus outside concentration of potassium, sodium, chloride, and other ions across cells' or ORGANELLES membranes. For excitable cells, the resting membrane potentials range between -30 and -100 millivolts. Physical, chemical, or electrical stimuli can make a membrane potential more negative (hyperpolarization), or less negative (depolarization).Membranes, Artificial: Artificially produced membranes, such as semipermeable membranes used in artificial kidney dialysis (RENAL DIALYSIS), monomolecular and bimolecular membranes used as models to simulate biological CELL MEMBRANES. These membranes are also used in the process of GUIDED TISSUE REGENERATION.Membrane Fluidity: The motion of phospholipid molecules within the lipid bilayer, dependent on the classes of phospholipids present, their fatty acid composition and degree of unsaturation of the acyl chains, the cholesterol concentration, and temperature.Protein Structure, Tertiary: 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.Protein Binding: 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.Models, Biological: 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.Microscopy, Confocal: 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.Endocytosis: Cellular uptake of extracellular materials within membrane-limited vacuoles or microvesicles. ENDOSOMES play a central role in endocytosis.Lipoylation: Covalent attachment of LIPIDS and FATTY ACIDS to other compounds and PROTEINS.Molecular Sequence Data: 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.Cells, Cultured: 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.Microscopy, Immunoelectron: 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.Membrane Glycoproteins: Glycoproteins found on the membrane or surface of cells.Sphingomyelins: A class of sphingolipids found largely in the brain and other nervous tissue. They contain phosphocholine or phosphoethanolamine as their polar head group so therefore are the only sphingolipids classified as PHOSPHOLIPIDS.Erythrocyte Membrane: The semi-permeable outer structure of a red blood cell. It is known as a red cell 'ghost' after HEMOLYSIS.Microscopy, Fluorescence: 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.Chromatography, Thin Layer: Chromatography on thin layers of adsorbents rather than in columns. The adsorbent can be alumina, silica gel, silicates, charcoals, or cellulose. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Solubility: The ability of a substance to be dissolved, i.e. to form a solution with another substance. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Globosides: Glycosphingolipids containing N-acetylglucosamine (paragloboside) or N-acetylgalactosamine (globoside). Globoside is the P antigen on erythrocytes and paragloboside is an intermediate in the biosynthesis of erythrocyte blood group ABH and P 1 glycosphingolipid antigens. The accumulation of globoside in tissue, due to a defect in hexosaminidases A and B, is the cause of Sandhoff disease.Recombinant Fusion Proteins: 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.Lipid Bilayers: Layers of lipid molecules which are two molecules thick. Bilayer systems are frequently studied as models of biological membranes.Amino Acid Sequence: 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.Cell Membrane Permeability: A quality of cell membranes which permits the passage of solvents and solutes into and out of cells.Galactosylceramides: Cerebrosides which contain as their polar head group a galactose moiety bound in glycosidic linkage to the hydroxyl group of ceramide. Their accumulation in tissue, due to a defect in beta-galactosidase, is the cause of galactosylceramide lipidosis or globoid cell leukodystrophy.Forssman Antigen: A glycolipid, cross-species antigen that induces production of antisheep hemolysin. It is present on the tissue cells of many species but absent in humans. It is found in many infectious agents.Liposomes: Artificial, single or multilaminar vesicles (made from lecithins or other lipids) that are used for the delivery of a variety of biological molecules or molecular complexes to cells, for example, drug delivery and gene transfer. They are also used to study membranes and membrane proteins.Cell Fractionation: Techniques to partition various components of the cell into SUBCELLULAR FRACTIONS.Carrier Proteins: Transport proteins that carry specific substances in the blood or across cell membranes.Cricetinae: A subfamily in the family MURIDAE, comprising the hamsters. Four of the more common genera are Cricetus, CRICETULUS; MESOCRICETUS; and PHODOPUS.Ceramides: Members of the class of neutral glycosphingolipids. They are the basic units of SPHINGOLIPIDS. They are sphingoids attached via their amino groups to a long chain fatty acyl group. They abnormally accumulate in FABRY DISEASE.Caveolin 3: A caveolin that is expressed exclusively in MUSCLE CELLS and is sufficient to form CAVEOLAE in SARCOLEMMA. Mutations in caveolin 3 are associated with multiple muscle diseases including DISTAL MYOPATHY and LIMB-GIRDLE MUSCULAR DYSTROPHY.Microscopy, Electron: 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.Mutation: 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.Cytoskeleton: The network of filaments, tubules, and interconnecting filamentous bridges which give shape, structure, and organization to the cytoplasm.src-Family Kinases: A PROTEIN-TYROSINE KINASE family that was originally identified by homology to the Rous sarcoma virus ONCOGENE PROTEIN PP60(V-SRC). They interact with a variety of cell-surface receptors and participate in intracellular signal transduction pathways. Oncogenic forms of src-family kinases can occur through altered regulation or expression of the endogenous protein and by virally encoded src (v-src) genes.Antigens, CD9: A subtype of tetraspanin proteins that play a role in cell adhesion, cell motility, and tumor metastasis. CD9 antigens take part in the process of platelet activation and aggregation, the formation of paranodal junctions in neuronal tissue, and the fusion of sperm with egg.Calcium: 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.Basement Membrane: A darkly stained mat-like EXTRACELLULAR MATRIX (ECM) that separates cell layers, such as EPITHELIUM from ENDOTHELIUM or a layer of CONNECTIVE TISSUE. The ECM layer that supports an overlying EPITHELIUM or ENDOTHELIUM is called basal lamina. Basement membrane (BM) can be formed by the fusion of either two adjacent basal laminae or a basal lamina with an adjacent reticular lamina of connective tissue. BM, composed mainly of TYPE IV COLLAGEN; glycoprotein LAMININ; and PROTEOGLYCAN, provides barriers as well as channels between interacting cell layers.Subcellular Fractions: 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)Lactosylceramides: Glycosphingolipids which contain as their polar head group a lactose moiety bound in glycosidic linkage to the hydroxyl group of ceramide. Their accumulation in tissue, due to a defect in lactosylceramide beta-galactosidase, is the cause of lactosylceramidosis.Golgi Apparatus: 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)Transfection: 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.HeLa Cells: 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.Gangliosides: A subclass of ACIDIC GLYCOSPHINGOLIPIDS. They contain one or more sialic acid (N-ACETYLNEURAMINIC ACID) residues. Using the Svennerholm system of abbrevations, gangliosides are designated G for ganglioside, plus subscript M, D, or T for mono-, di-, or trisialo, respectively, the subscript letter being followed by a subscript arabic numeral to indicated sequence of migration in thin-layer chromatograms. (From Oxford Dictionary of Biochemistry and Molecular Biology, 1997)Lipids: A generic term for fats and lipoids, the alcohol-ether-soluble constituents of protoplasm, which are insoluble in water. They comprise the fats, fatty oils, essential oils, waxes, phospholipids, glycolipids, sulfolipids, aminolipids, chromolipids (lipochromes), and fatty acids. (Grant & Hackh's Chemical Dictionary, 5th ed)COS Cells: 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).)Jurkat Cells: A CELL LINE derived from human T-CELL LEUKEMIA and used to determine the mechanism of differential susceptibility to anti-cancer drugs and radiation.Green Fluorescent Proteins: 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.Endosomes: Cytoplasmic vesicles formed when COATED VESICLES shed their CLATHRIN coat. Endosomes internalize macromolecules bound by receptors on the cell surface.Cholera Toxin: An ENTEROTOXIN from VIBRIO CHOLERAE. It consists of two major protomers, the heavy (H) or A subunit and the B protomer which consists of 5 light (L) or B subunits. The catalytic A subunit is proteolytically cleaved into fragments A1 and A2. The A1 fragment is a MONO(ADP-RIBOSE) TRANSFERASE. The B protomer binds cholera toxin to intestinal epithelial cells, and facilitates the uptake of the A1 fragment. The A1 catalyzed transfer of ADP-RIBOSE to the alpha subunits of heterotrimeric G PROTEINS activates the production of CYCLIC AMP. Increased levels of cyclic AMP are thought to modulate release of fluid and electrolytes from intestinal crypt cells.Blotting, Western: 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.Trihexosylceramides: Glycosphingolipids which contain as their polar head group a trisaccharide (galactose-galactose-glucose) moiety bound in glycosidic linkage to the hydroxyl group of ceramide. Their accumulation in tissue, due to a defect in ceramide trihexosidase, is the cause of angiokeratoma corporis diffusum (FABRY DISEASE).Fluorescence Resonance Energy Transfer: A type of FLUORESCENCE SPECTROSCOPY using two FLUORESCENT DYES with overlapping emission and absorption spectra, which is used to indicate proximity of labeled molecules. This technique is useful for studying interactions of molecules and PROTEIN FOLDING.Time Factors: Elements of limited time intervals, contributing to particular results or situations.Membrane Transport Proteins: 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.Saprolegnia: A genus of OOMYCETES in the family Saprolegniaceae. It is a parasite and pathogen of freshwater FISHES.Fluorescent Antibody Technique: 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.Palmitic Acid: A common saturated fatty acid found in fats and waxes including olive oil, palm oil, and body lipids.Fluorescent Dyes: Agents that emit light after excitation by light. The wave length of the emitted light is usually longer than that of the incident light. Fluorochromes are substances that cause fluorescence in other substances, i.e., dyes used to mark or label other compounds with fluorescent tags.Actins: Filamentous proteins that are the main constituent of the thin filaments of muscle fibers. The filaments (known also as filamentous or F-actin) can be dissociated into their globular subunits; each subunit is composed of a single polypeptide 375 amino acids long. This is known as globular or G-actin. In conjunction with MYOSINS, actin is responsible for the contraction and relaxation of muscle.Enzyme Activation: Conversion of an inactive form of an enzyme to one possessing metabolic activity. It includes 1, activation by ions (activators); 2, activation by cofactors (coenzymes); and 3, conversion of an enzyme precursor (proenzyme or zymogen) to an active enzyme.Clathrin: The main structural coat protein of COATED VESICLES which play a key role in the intracellular transport between membranous organelles. Each molecule of clathrin consists of three light chains (CLATHRIN LIGHT CHAINS) and three heavy chains (CLATHRIN HEAVY CHAINS) that form a structure called a triskelion. Clathrin also interacts with cytoskeletal proteins.Lipid Metabolism: Physiological processes in biosynthesis (anabolism) and degradation (catabolism) of LIPIDS.Antigens, CD: Differentiation antigens residing on mammalian leukocytes. CD stands for cluster of differentiation, which refers to groups of monoclonal antibodies that show similar reactivity with certain subpopulations of antigens of a particular lineage or differentiation stage. The subpopulations of antigens are also known by the same CD designation.Sphingomyelin Phosphodiesterase: An enzyme that catalyzes the hydrolysis of sphingomyelin to ceramide (N-acylsphingosine) plus choline phosphate. A defect in this enzyme leads to NIEMANN-PICK DISEASE. EC 3.1.4.12.Protein Processing, Post-Translational: 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.Cell Line, Tumor: A cell line derived from cultured tumor cells.Phosphorylation: The introduction of a phosphoryl group into a compound through the formation of an ester bond between the compound and a phosphorus moiety.CHO Cells: 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.Carbohydrate Sequence: The sequence of carbohydrates within POLYSACCHARIDES; GLYCOPROTEINS; and GLYCOLIPIDS.Immunoprecipitation: 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.Antigens, CD81: Tetraspanin proteins that are involved in a variety of cellular functions including BASEMENT MEMBRANE assembly, and in the formation of a molecular complexes on the surface of LYMPHOCYTES.PhosphoproteinsLuminescent Proteins: 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.Mitochondrial Membranes: The two lipoprotein layers in the MITOCHONDRION. The outer membrane encloses the entire mitochondrion and contains channels with TRANSPORT PROTEINS to move molecules and ions in and out of the organelle. The inner membrane folds into cristae and contains many ENZYMES important to cell METABOLISM and energy production (MITOCHONDRIAL ATP SYNTHASE).Kinetics: The rate dynamics in chemical or physical systems.Cercopithecus aethiops: 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.Receptors, Cell Surface: Cell surface proteins that bind signalling molecules external to the cell with high affinity and convert this extracellular event into one or more intracellular signals that alter the behavior of the target cell (From Alberts, Molecular Biology of the Cell, 2nd ed, pp693-5). Cell surface receptors, unlike enzymes, do not chemically alter their ligands.Cell Polarity: Orientation of intracellular structures especially with respect to the apical and basolateral domains of the plasma membrane. Polarized cells must direct proteins from the Golgi apparatus to the appropriate domain since tight junctions prevent proteins from diffusing between the two domains.Glucosylceramides: Cerebrosides which contain as their polar head group a glucose moiety bound in glycosidic linkage to the hydroxyl group of ceramides. Their accumulation in tissue, due to a defect in beta-glucosidase, is the cause of Gaucher's disease.Cerebrosides: Neutral glycosphingolipids that contain a monosaccharide, normally glucose or galactose, in 1-ortho-beta-glycosidic linkage with the primary alcohol of an N-acyl sphingoid (ceramide). In plants the monosaccharide is normally glucose and the sphingoid usually phytosphingosine. In animals, the monosaccharide is usually galactose, though this may vary with the tissue and the sphingoid is usually sphingosine or dihydrosphingosine. (From Oxford Dictionary of Biochemistry and Molecular Biology, 1st ed)Epithelial Cells: Cells that line the inner and outer surfaces of the body by forming cellular layers (EPITHELIUM) or masses. Epithelial cells lining the SKIN; the MOUTH; the NOSE; and the ANAL CANAL derive from ectoderm; those lining the RESPIRATORY SYSTEM and the DIGESTIVE SYSTEM derive from endoderm; others (CARDIOVASCULAR SYSTEM and LYMPHATIC SYSTEM) derive from mesoderm. Epithelial cells can be classified mainly by cell shape and function into squamous, glandular and transitional epithelial cells.T-Lymphocytes: Lymphocytes responsible for cell-mediated immunity. Two types have been identified - cytotoxic (T-LYMPHOCYTES, CYTOTOXIC) and helper T-lymphocytes (T-LYMPHOCYTES, HELPER-INDUCER). They are formed when lymphocytes circulate through the THYMUS GLAND and differentiate to thymocytes. When exposed to an antigen, they divide rapidly and produce large numbers of new T cells sensitized to that antigen.Lymphocyte Specific Protein Tyrosine Kinase p56(lck): This enzyme is a lymphoid-specific src family tyrosine kinase that is critical for T-cell development and activation. Lck is associated with the cytoplasmic domains of CD4, CD8 and the beta-chain of the IL-2 receptor, and is thought to be involved in the earliest steps of TCR-mediated T-cell activation.Bacterial Proteins: Proteins found in any species of bacterium.Cell Adhesion: Adherence of cells to surfaces or to other cells.Phosphatidylcholines: Derivatives of phosphatidic acids in which the phosphoric acid is bound in ester linkage to a choline moiety. Complete hydrolysis yields 1 mole of glycerol, phosphoric acid and choline and 2 moles of fatty acids.Binding Sites: The parts of a macromolecule that directly participate in its specific combination with another molecule.Ustilaginales: An order of basidiomycetous fungi; some species are parasitic on grasses (POACEAE) and maize.Models, Molecular: Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.Endoplasmic Reticulum: 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)Cell Compartmentation: A partitioning within cells due to the selectively permeable membranes which enclose each of the separate parts, e.g., mitochondria, lysosomes, etc.Escherichia coli: A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.Receptors, Antigen, T-Cell: Molecules on the surface of T-lymphocytes that recognize and combine with antigens. The receptors are non-covalently associated with a complex of several polypeptides collectively called CD3 antigens (ANTIGENS, CD3). Recognition of foreign antigen and the major histocompatibility complex is accomplished by a single heterodimeric antigen-receptor structure, composed of either alpha-beta (RECEPTORS, ANTIGEN, T-CELL, ALPHA-BETA) or gamma-delta (RECEPTORS, ANTIGEN, T-CELL, GAMMA-DELTA) chains.Biological Transport: 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.Electrophoresis, Polyacrylamide Gel: Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.Antigens, CD1d: A major histocompatibily complex class I-like protein that plays a unique role in the presentation of lipid ANTIGENS to NATURAL KILLER T-CELLS.Centrifugation, Density Gradient: 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)Ligands: A molecule that binds to another molecule, used especially to refer to a small molecule that binds specifically to a larger molecule, e.g., an antigen binding to an antibody, a hormone or neurotransmitter binding to a receptor, or a substrate or allosteric effector binding to an enzyme. Ligands are also molecules that donate or accept a pair of electrons to form a coordinate covalent bond with the central metal atom of a coordination complex. (From Dorland, 27th ed)Precipitin Tests: 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.Virus Assembly: The assembly of VIRAL STRUCTURAL PROTEINS and nucleic acid (VIRAL DNA or VIRAL RNA) to form a VIRUS PARTICLE.Glycosylation: 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.Neurons: The basic cellular units of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the NERVOUS SYSTEM.Phospholipids: Lipids containing one or more phosphate groups, particularly those derived from either glycerol (phosphoglycerides see GLYCEROPHOSPHOLIPIDS) or sphingosine (SPHINGOLIPIDS). They are polar lipids that are of great importance for the structure and function of cell membranes and are the most abundant of membrane lipids, although not stored in large amounts in the system.Antigens, CD1: Glycoproteins expressed on cortical thymocytes and on some dendritic cells and B-cells. Their structure is similar to that of MHC Class I and their function has been postulated as similar also. CD1 antigens are highly specific markers for human LANGERHANS CELLS.Polyethylene Glycols: Polymers of ETHYLENE OXIDE and water, and their ethers. They vary in consistency from liquid to solid depending on the molecular weight indicated by a number following the name. They are used as SURFACTANTS, dispersing agents, solvents, ointment and suppository bases, vehicles, and tablet excipients. Some specific groups are NONOXYNOLS, OCTOXYNOLS, and POLOXAMERS.Mice, Knockout: 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.Hydrogen-Ion Concentration: The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH = log 1/2[1/(H+)], where (H+) is the hydrogen ion concentration in gram equivalents per liter of solution. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Proteomics: The systematic study of the complete complement of proteins (PROTEOME) of organisms.Sulfoglycosphingolipids: GLYCOSPHINGOLIPIDS with a sulfate group esterified to one of the sugar groups.RNA, Small Interfering: 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.Vesicular stomatitis Indiana virus: The type species of VESICULOVIRUS causing a disease symptomatically similar to FOOT-AND-MOUTH DISEASE in cattle, horses, and pigs. It may be transmitted to other species including humans, where it causes influenza-like symptoms.Immunohistochemistry: Histochemical localization of immunoreactive substances using labeled antibodies as reagents.Mice, Inbred C57BLBase Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.Sequence Homology, Amino Acid: The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.Calcium Signaling: 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.Cord Factors: Toxic glycolipids composed of trehalose dimycolate derivatives. They are produced by MYCOBACTERIUM TUBERCULOSIS and other species of MYCOBACTERIUM. They induce cellular dysfunction in animals.Fatty Acids: Organic, monobasic acids derived from hydrocarbons by the equivalent of oxidation of a methyl group to an alcohol, aldehyde, and then acid. Fatty acids are saturated and unsaturated (FATTY ACIDS, UNSATURATED). (Grant & Hackh's Chemical Dictionary, 5th ed)Cross-Linking Reagents: Reagents with two reactive groups, usually at opposite ends of the molecule, that are capable of reacting with and thereby forming bridges between side chains of amino acids in proteins; the locations of naturally reactive areas within proteins can thereby be identified; may also be used for other macromolecules, like glycoproteins, nucleic acids, or other.Phospholipase D: An enzyme found mostly in plant tissue. It hydrolyzes glycerophosphatidates with the formation of a phosphatidic acid and a nitrogenous base such as choline. This enzyme also catalyzes transphosphatidylation reactions. EC 3.1.4.4.Microvilli: Minute projections of cell membranes which greatly increase the surface area of the cell.Synaptic Membranes: Cell membranes associated with synapses. Both presynaptic and postsynaptic membranes are included along with their integral or tightly associated specializations for the release or reception of transmitters.Mass Spectrometry: An analytical method used in determining the identity of a chemical based on its mass using mass analyzers/mass spectrometers.PC12 Cells: A CELL LINE derived from a PHEOCHROMOCYTOMA of the rat ADRENAL MEDULLA. PC12 cells stop dividing and undergo terminal differentiation when treated with NERVE GROWTH FACTOR, making the line a useful model system for NERVE CELL differentiation.Cytoplasm: 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)Mitochondria: 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)Temperature: 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.Enzyme Inhibitors: Compounds or agents that combine with an enzyme in such a manner as to prevent the normal substrate-enzyme combination and the catalytic reaction.Tumor Cells, Cultured: Cells grown in vitro from neoplastic tissue. If they can be established as a TUMOR CELL LINE, they can be propagated in cell culture indefinitely.Lymphocyte Activation: Morphologic alteration of small B LYMPHOCYTES or T LYMPHOCYTES in culture into large blast-like cells able to synthesize DNA and RNA and to divide mitotically. It is induced by INTERLEUKINS; MITOGENS such as PHYTOHEMAGGLUTININS, and by specific ANTIGENS. It may also occur in vivo as in GRAFT REJECTION.Cricetulus: 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.Exocytosis: Cellular release of material within membrane-limited vesicles by fusion of the vesicles with the CELL MEMBRANE.Recombinant Proteins: Proteins prepared by recombinant DNA technology.Cell Differentiation: Progressive restriction of the developmental potential and increasing specialization of function that leads to the formation of specialized cells, tissues, and organs.Flow Cytometry: Technique using an instrument system for making, processing, and displaying one or more measurements on individual cells obtained from a cell suspension. Cells are usually stained with one or more fluorescent dyes specific to cell components of interest, e.g., DNA, and fluorescence of each cell is measured as it rapidly transverses the excitation beam (laser or mercury arc lamp). Fluorescence provides a quantitative measure of various biochemical and biophysical properties of the cell, as well as a basis for cell sorting. Other measurable optical parameters include light absorption and light scattering, the latter being applicable to the measurement of cell size, shape, density, granularity, and stain uptake.Down-Regulation: A negative regulatory effect on physiological processes at the molecular, cellular, or systemic level. At the molecular level, the major regulatory sites include membrane receptors, genes (GENE EXPRESSION REGULATION), mRNAs (RNA, MESSENGER), and proteins.Diffusion: The tendency of a gas or solute to pass from a point of higher pressure or concentration to a point of lower pressure or concentration and to distribute itself throughout the available space. Diffusion, especially FACILITATED DIFFUSION, is a major mechanism of BIOLOGICAL TRANSPORT.Cattle: Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.Protein Conformation: 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).Erythrocytes: Red blood cells. Mature erythrocytes are non-nucleated, biconcave disks containing HEMOGLOBIN whose function is to transport OXYGEN.Magnetic Resonance Spectroscopy: Spectroscopic method of measuring the magnetic moment of elementary particles such as atomic nuclei, protons or electrons. It is employed in clinical applications such as NMR Tomography (MAGNETIC RESONANCE IMAGING).Rabbits: 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.Cytosol: Intracellular fluid from the cytoplasm after removal of ORGANELLES and other insoluble cytoplasmic components.Brain: The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.Proteins: 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.Cloning, Molecular: 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.Viral Envelope Proteins: 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.Galactolipids: A group of GLYCOLIPIDS in which the sugar group is GALACTOSE. They are distinguished from GLYCOSPHINGOLIPIDS in lacking nitrogen. They constitute the majority of MEMBRANE LIPIDS in PLANTS.Protein-Tyrosine Kinases: Protein kinases that catalyze the PHOSPHORYLATION of TYROSINE residues in proteins with ATP or other nucleotides as phosphate donors.Antigens, CD4: 55-kDa antigens found on HELPER-INDUCER T-LYMPHOCYTES and on a variety of other immune cell types. CD4 antigens are members of the immunoglobulin supergene family and are implicated as associative recognition elements in MAJOR HISTOCOMPATIBILITY COMPLEX class II-restricted immune responses. On T-lymphocytes they define the helper/inducer subset. CD4 antigens also serve as INTERLEUKIN-15 receptors and bind to the HIV receptors, binding directly to the HIV ENVELOPE PROTEIN GP120.Molecular Weight: The sum of the weight of all the atoms in a molecule.Lysosomes: 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)Antibodies, Monoclonal: Antibodies produced by a single clone of cells.Immunoblotting: 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.Tetraspanins: A large superfamily of cell surface membrane proteins characterized by their four transmembrane domains. They play a role in a variety of processes such as cellular adhesion and motility. They may be involved in the organization of cell surface MEMBRANE MICRODOMAINS that regulate the activation of LEUKOCYTES.Transport Vesicles: Vesicles that are involved in shuttling cargo from the interior of the cell to the cell surface, from the cell surface to the interior, across the cell or around the cell to various locations.Saccharomyces cerevisiae Proteins: 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.Peptides: 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.Natural Killer T-Cells: A specialized subset of T-LYMPHOCYTES that exhibit features of INNATE IMMUNITY similar to that of NATURAL KILLER CELLS. They are reactive to glycolipids presented in the context of the major histocompatibility complex (MHC) class I-like molecule, CD1D ANTIGEN.Amino Acid Motifs: 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.Carbohydrate Conformation: The characteristic 3-dimensional shape of a carbohydrate.Mycobacterium leprae: A species of gram-positive, aerobic bacteria that causes LEPROSY in man. Its organisms are generally arranged in clumps, rounded masses, or in groups of bacilli side by side.Apoptosis: 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.Glycoproteins: Conjugated protein-carbohydrate compounds including mucins, mucoid, and amyloid glycoproteins.Galactosyltransferases: Enzymes that catalyze the transfer of galactose from a nucleoside diphosphate galactose to an acceptor molecule which is frequently another carbohydrate. EC 2.4.1.-.Extraembryonic Membranes: The thin layers of tissue that surround the developing embryo. There are four extra-embryonic membranes commonly found in VERTEBRATES, such as REPTILES; BIRDS; and MAMMALS. They are the YOLK SAC, the ALLANTOIS, the AMNION, and the CHORION. These membranes provide protection and means to transport nutrients and wastes.Gene Expression Regulation: 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.Structure-Activity Relationship: The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.RNA, Messenger: 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.Phosphatidylinositols: Derivatives of phosphatidic acids in which the phosphoric acid is bound in ester linkage to the hexahydroxy alcohol, myo-inositol. Complete hydrolysis yields 1 mole of glycerol, phosphoric acid, myo-inositol, and 2 moles of fatty acids.Protein Structure, Secondary: The level of protein structure in which regular hydrogen-bond interactions within contiguous stretches of polypeptide chain give rise to alpha helices, beta strands (which align to form beta sheets) or other types of coils. This is the first folding level of protein conformation.Molecular Conformation: The characteristic three-dimensional shape of a molecule.Tyrosine: A non-essential amino acid. In animals it is synthesized from PHENYLALANINE. It is also the precursor of EPINEPHRINE; THYROID HORMONES; and melanin.Adenosine Triphosphate: 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.HIV-1: The type species of LENTIVIRUS and the etiologic agent of AIDS. It is characterized by its cytopathic effect and affinity for the T4-lymphocyte.Spectrometry, Fluorescence: Measurement of the intensity and quality of fluorescence.

*Lipid raft

These specialised membrane microdomains compartmentalise cellular processes by serving as organising centers for the assembly ... Netherlands refocused interest on these membrane microdomains, enriched with lipids and cholesterol, glycolipids, and ... Caveolae Cell membrane Cholesterol Lipid microdomain Membrane proteins Sphingomyelin Thomas, Sunil; Preda-Pais, Anca; Casares, ... and sphingolipid-enriched domains that compartmentalize cellular processes. Small rafts can sometimes be stabilized to form ...

*Cell membrane

Lipid rafts and caveolae are examples of cholesterol-enriched microdomains in the cell membrane.[21] Also, a fraction of the ... cell membranes are involved in a variety of cellular processes such as cell adhesion, ion conductivity and cell signalling and ... The cell membrane consists of three classes of amphipathic lipids: phospholipids, glycolipids, and sterols. The amount of each ... plasmatic membrane (Pfeffer, 1900),[13] plasma membrane, cytoplasmic membrane, cell envelope and cell membrane.[14][15] Some ...

*Cell membrane

Lipid rafts and caveolae are examples of cholesterol-enriched microdomains in the cell membrane.[21] Also, a fraction of the ... cell membranes are involved in a variety of cellular processes such as cell adhesion, ion conductivity and cell signalling and ... The cell membrane consists of three classes of amphipathic lipids: phospholipids, glycolipids, and sterols. The amount of each ... plasmatic membrane (Pfeffer, 1900),[13] plasma membrane, cytoplasmic membrane, cell envelope and cell membrane.[14][15] Some ...

*Cell membrane

Lipid rafts and caveolae are examples of cholesterol-enriched microdomains in the cell membrane.[22] Also, a fraction of the ... cell membranes are involved in a variety of cellular processes such as cell adhesion, ion conductivity and cell signalling and ... The cell membrane consists of three classes of amphipathic lipids: phospholipids, glycolipids, and sterols. The amount of each ... plasmatic membrane (Pfeffer, 1900),[14] plasma membrane, cytoplasmic membrane, cell envelope and cell membrane.[15][16] Some ...

*Cell membrane

In addition, cell membranes are involved in a variety of cellular processes such as cell adhesion, ion conductivity and cell ... Lipid rafts and caveolae are examples of cholesterol-enriched microdomains in the cell membrane. Also, a fraction of the lipid ... The cell membrane consists of three classes of amphipathic lipids: phospholipids, glycolipids, and sterols. The amount of each ... plasmatic membrane (Pfeffer, 1900), plasma membrane, cytoplasmic membrane, cell envelope and cell membrane. Some authors that ...

*Sulfatide

MAL is also believed to form membrane microdomains (small regions on the membrane with distinct structure and function) in ... into the membrane of the host cell. This allows the HIV-1 virus to enter into the cell. Gp120 can also bind to glycolipids like ... However, the sulfatide enriched cells also have a small reduction in initial infection compared to the parent cells. The ... Sulfatide also plays a role in several physiological processes and systems, including the nervous system, the immune system, ...
TY - JOUR. T1 - Human immunodeficiency virus type 1 enters brain microvascular endothelia by macropinocytosis dependent on lipid rafts and the mitogen-activated protein kinase signaling pathway. AU - Liu, Nancy Q.. AU - Lossinsky, Albert S.. AU - Popik, Waldemar. AU - Li, Xia. AU - Gujuluva, Chandrasekhar. AU - Kriederman, Benjamin. AU - Roberts, Jaclyn. AU - Pushkarsky, Tatania. AU - Bukrinsky, Michael. AU - Witte, Marlys. AU - Weinand, Martin. AU - Fiala, Milan. PY - 2002/6/25. Y1 - 2002/6/25. N2 - Brain microvascular endothelial cells (BMVECs) present an incomplete barrier to human immunodeficiency virus type 1 (HIV-1) neuroinvasion. In order to clarify the mechanisms of HIV-1 invasion, we have examined HIV-1 uptake and transcellular penetration in an in vitro BMVEC model. No evidence of productive infection was observed by luciferase, PCR, and reverse transcriptase assays. Approximately 1% of viral RNA and 1% of infectious virus penetrated the BMVEC barrier without disruption of tight ...
Lipid rafts, sterol- and sphingolipid-rich membrane microdomains, have been shown to control virulence in a variety of parasites including Entamoeba histolytica, an intestinal parasite that causes dysentery and liver abscess. Parasite cell surface receptors, such as the Gal/GalNAc lectin, facilitate attachment to host cells and extracellular matrix. The Gal/GalNAc lectin binds to galactose or N-acetylgalactosamine residues on host components, and is composed of heavy (Hgl), intermediate (Igl), and light (Lgl) subunits. Although Igl is constitutively localized to lipid rafts, Hgl and Lgl transiently associate with this compartment in a cholesterol-dependent fashion. Exposure to bonafide Gal/GalNAc lectin ligands is associated with enrichment of the subunits in rafts. Direct lectin-ligand interactions and sufficient levels of both PIP2 and calcium were shown to be necessary for lectin enrichment in rafts. Additionally, an initial analysis of both ...
Caveolae and rafts represent highly heterogeneous populations of functionally distinct membrane domains (Maxfield, 2002). Multiple raft-associated proteins may therefore serve to segregate and define raft domains that exhibit differential endocytic capacities. The existence of multiple caveolin-1 binding partners (Liu et al., 2002) implicates caveolin-1 as a scaffolding molecule that determines the cargo for caveolae/raft-dependent endocytosis. Caveolae/raft ligands are also internalized by other endocytic pathways. For instance, cholera, shiga, and anthrax toxins bind to cell surface raft domains and yet are internalized via clathrin-dependent pathways (Sandvig et al., 1989; Shogomori and Futerman, 2001; Abrami et al., 2003). Raft association cannot therefore be considered a criterion in and of itself for internalization via the caveolae/raft-dependent pathway.. Two caveolar ligands, SV40 and CTX, are delivered to a caveolin-1-positive endocytic compartment or caveosome (Parton et al., ...
This is the first report that two different DIG fractions can be isolated from myelin by TX-100 extraction with sodium phosphate buffer lacking EDTA/EGTA, at room temperature. Both of these fractions have characteristics of GSL/cholesterol-enriched membrane domains based on their TX-100 insolubility, high ratios of cholesterol and GalC to phospholipid, enrichment in the GPI-linked protein NCAM120, and buoyancy on a sucrose density gradient. However, B2 also contained the cytoskeletal proteins actin and tubulin, and the raft markers flotillin-1, caveolin and GM1, and thus may consist of caveolae or other types of GSL/cholesterol-enriched membrane domain associated with cytoskeletal proteins. It does not contain non-membrane-associated cytoskeleton, which would sediment faster to a much higher density.. This finding of a caveolin-containing type of membrane domain associated with cytoskeletal proteins in ...
The cholesterol-enriched membrane microdomains lipid rafts play a key role in cell activation by recruiting and excluding specific signalling components of cell-surface receptors upon receptor engagement. Our previous studies have demonstrated that the GPI (glycosylphosphatidylinositol)-linked uPAR [uPA (urokinase-type plasminogen activator) receptor], which can be found in lipid rafts and in non-raft fractions, can mediate the differentiation of VSMCs (vascular smooth muscle cells) towards a pathophysiological de-differentiated phenotype. However, the mechanism by which uPAR and its ligand uPA regulate VSMC phenotypic changes is not known. In the present study, we provide evidence that the molecular machinery of uPAR-mediated VSMC differentiation employs lipid rafts. We show that the disruption of rafts in VSMCs by membrane cholesterol depletion using MCD (methyl-β-cyclodextrin) or filipin leads to the up-regulation of uPAR and cell ...
Reggie-1 and -2 proteins (flotillin-2 and -1 respectively) form their own type of non-caveolar membrane microdomains, which are involved in important cellular processes such as T-cell activation, phagocytosis and signalling mediated by the cellular prion protein and insulin; this is consistent with the notion that reggie microdomains promote protein assemblies and signalling. While it is generally known that membrane microdomains contain large multiprotein assemblies, the exact organization of reggie microdomains remains elusive. Using chemical cross-linking approaches, we have demonstrated that reggie complexes are composed of homo- and hetero-tetramers of reggie-1 and -2. Moreover, native reggie oligomers are indeed quite stable, since non-cross-linked tetramers are resistant to 8 M urea treatment. We also show that oligomerization requires the C-terminal ...
TY - JOUR. T1 - Solid-State 13C NMR reveals annealing of raft-like membranes containing cholesterol by the intrinsically disordered protein α-synuclein. AU - Leftin, Avigdor. AU - Job, Constantin. AU - Beyer, Klaus. AU - Brown, Michael F. PY - 2013/8/23. Y1 - 2013/8/23. N2 - Misfolding and aggregation of the intrinsically disordered protein α-Synuclein (αS) in Lewy body plaques are characteristic markers of late-stage Parkinsons disease. It is well established that membrane binding is initiated at the N-terminus of the protein and affects biasing of conformational ensembles of αS. However, little is understood about the effect of αS on the membrane lipid bilayer. One hypothesis is that intrinsically disordered αS alters the structural properties of the membrane, thereby stabilizing the bilayer against fusion. Here, we used two-dimensional 13C separated local-field NMR to study interaction of the wild-type α-Synuclein (wt-αS) or its ...
We identified p18 as a potential component of lipid rafts. The predominant distribution of p18 to DRMs suggested its potential localization to lipid rafts. However, it is currently accepted that DRMs do not necessarily correspond to lipid rafts and that the DRM separation method is insufficient for the identification of lipid raft‐associated proteins (Lichtenberg et al, 2005; Hancock, 2006). Thus, to verify the raft localization of p18, we examined intracellular distribution of p18 and its mutants. The cell staining analyses showed that p18 could be colocalized with GM1 ganglioside, a marker of lipid rafts (Harder et al, 1998), and that the N‐terminal potential myristoylation and palmitoylation sites, which are known to function as lipid raft localization signals, were required for the late endosome localization of p18. These observations strongly supported the presence of p18 in lipid rafts of late endosomes (Balbis et al, 2007). It is of interest that the N‐terminal only 20 residues of ...
The C-type lectin-like receptor 2 (CLEC-2)activates platelets through Src and Syk tyrosine kinases via a single cytoplasmic YxxL motif known as a hem immunoreceptor tyrosine-based activation motif (hemITAM).Here, we demonstrate using sucrose gradient ultracentrifugation and methyl--cyclodextrin treatment that CLEC-2 translocates to lipid rafts upon ligand engagement and that translocation is essential for hemITAM phosphorylation and signal initiation. HemITAM phosphorylation, but not translocation, is also critically dependent on actin polymerization,Rac1 activation, and release of ADP and thromboxane A2 (TxA2). The role of ADP and TxA2 in mediating hosphorylation is dependent on ligand engagement and rac activation but is independent of platelet aggregation. In contrast,tyrosine phosphorylation of the GPVIFcR -chain ITAM, which has 2 YxxL motifs,is independent of actin polymerization and secondary mediators. These results reveal a unique series of proximal events in CLEC-2 phosphorylation ...
Although the accumulation of lipid rafts at the immunological synapse is now well accepted, the degree of the accumulation, the localization within the fine structure of the immunological synapse, and the region from which lipid rafts are recruited have not been defined. In this work we show that lipid rafts preferentially accumulate in the central zone of the immunological synapse, the central supramolecular activation complex (C-SMAC). However, quantitative analyses indicate that the level of recruitment of lipid rafts to the C-SMAC is relatively small and suggests that rearrangement of lipid rafts from the peripheral zone of the synapse into the C-SMAC can account for this accumulation. We also assessed the effects of CD28 deficiency on lipid raft recruitment to the immunological synapse. The accumulation of lipid occurred independently of the CD28/B7 system and was not measurably altered by CD28.
Although the accumulation of lipid rafts at the immunological synapse is now well accepted, the degree of the accumulation, the localization within the fine structure of the immunological synapse, and the region from which lipid rafts are recruited have not been defined. In this work we show that lipid rafts preferentially accumulate in the central zone of the immunological synapse, the central supramolecular activation complex (C-SMAC). However, quantitative analyses indicate that the level of recruitment of lipid rafts to the C-SMAC is relatively small and suggests that rearrangement of lipid rafts from the peripheral zone of the synapse into the C-SMAC can account for this accumulation. We also assessed the effects of CD28 deficiency on lipid raft recruitment to the immunological synapse. The accumulation of lipid occurred independently of the CD28/B7 system and was not measurably altered by CD28.
The acquisition of spatial and functional asymmetry between the rear and the front of the cell is a necessary step for cell chemotaxis. Insulin-like growth factor-I (IGF-I) stimulation of the human adenocarcinoma MCF-7 induces a polarized phenotype characterized by asymmetrical CCR5 chemokine receptor redistribution to the leading cell edge. CCR5 associates with membrane raft microdomains, and its polarization parallels redistribution of raft molecules, including the raft-associated ganglioside GM1, glycosylphosphatidylinositol-anchored green fluorescent protein and ephrinB1, to the leading edge. The non-raft proteins transferrin receptor and a mutant ephrinB1 are distributed homogeneously in migrating MCF-7 cells, supporting the raft localization requirement for polarization. IGF-I stimulation of cholesterol-depleted cells induces projection of multiple pseudopodia over the entire cell periphery, indicating that raft disruption specifically affects the acquisition of cell ...
Lipid rafts are plasma-membrane microdomains that are enriched in certain lipids (sphingolipids, glycosphingolipids and cholesterol), as well as in lipid-modified proteins. Rafts appear to exist in the liquid-ordered phase, which contributes to their partitioning from the surrounding liquid-disordered glycerophospholipid environment. DRM (detergent-resistant membrane) fractions isolated from cells are believed to represent coalesced lipid rafts. We have employed extraction using two different non-ionic detergents, Brij-96 and Triton X-100, to isolate detergent-resistant lipid rafts from rat basophilic leukaemia cell line RBL-2H3, and compared their properties with each other and with plasma-membrane vesicles. DRM fractions were isolated as sealed unilamellar vesicles of similar size (135-170 nm diameter), using either sucrose-density-gradient sedimentation or gel-filtration chromatography. Lipid rafts isolated using Brij-96 ...
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Soil contaminated with Cd and Pb has caused sharp decrease of cultivatable soil and has been attracting increasing attention. Biosurfactants are efficient in solving the problem. However, little information is available about the influence of sophorolipids (SLs) on the remediation of Cd- or Pb-contaminated soil. The sophorolipids produced by Starmerella bombicola CGMCC 1576 were used to study the effects of Cd and Pb removal in batch soil washing from artificially contaminated soil. The removal efficiency of crude total SLs was better than both distilled water and synthetic surfactants. Furthermore, 83.6% of Cd and 44.8% of Pb were removed by 8% crude acidic SLs. Acidic SLs with high water solubility were more effective than lactonic SLs in enhancing remediation of heavy metal-contaminated soils. The complexation of Cd with the free carboxyl group of the acidic SLs was observed by Fourier-transform infrared spectroscopy study, and this complexation was effective in heavy metal removal from the soil. The
TY - JOUR. T1 - Partitioning of proteins into plasma membrane microdomains. Clustering of mutant influenza virus hemagglutinins into coated pits depends on the strength of the internalization signal. AU - Fire, Ella. AU - Brown, Claire M.. AU - Roth, Michael G.. AU - Henis, Yoav I.. AU - Petersen, Nils O.. PY - 1997/11/21. Y1 - 1997/11/21. N2 - Internalization of membrane proteins involves their recruitment into plasma membrane clathrin-coated pits, with which they are thought to interact by binding to AP-2 adaptor protein complexes. To investigate the interactions of membrane proteins with coated pits at the cell surface, we applied image correlation spectroscopy to measure directly and quantitatively the clustering of influenza hemagglutinin (HA) protein mutants carrying specific cytoplasmic internalization signals. The HA system enables direct comparison between isolated internalization signals, because HA itself is ...
Hyaluronan is a major component of the extracellular matrix and plays pivotal roles in inflammation and cancer. Hyaluronan oligomers are frequently found in these pathological conditions, in which they exert their effects via association with the transmembrane receptor CD44. Lipid rafts are cholesterol- and glycosphingolipid-enriched membrane microdomains that may regulate membrane receptors while serving as platforms for transmembrane signaling at the cell surface. This article focuses on the recent discovery that lipid rafts regulate the interaction between CD44 and hyaluronan, which depends largely on hyaluronans size. Lipid rafts regulate CD44s ability to bind hyaluronan in T cells, control the rolling adhesion of lymphocytes on vascular endothelial cells, and regulate hyaluronan- and CD44-mediated cancer cell migration. The implications of these findings for preventing inflammatory ...
Cholesterol- and glycosphingolipid-enriched membrane lipid microdomains, frequently called lipid rafts, are thought to play an important role in the spatial and temporal organization of immunological synapses. Higher ordering of lipid acyl chains was suggested for these entities and imaging of membrane order in living cells during activation can therefore help to understand the mechanisms responsible for the supramolecular organization of molecules involved in the activation of T cells. Here, we employ the phase-sensitive membrane dye di-4-ANEPPDHQ together with a variety of spectrally-resolved microscopy techniques, including 2-channel ratiometric TIRF microscopy and fluorescence lifetime imaging, to characterize membrane order at the T cell immunological synapse at high spatial and temporal resolution in live cells at physiological temperature. We find that higher membrane order resides at ...
Lipid rafts are cholesterol- and glycosphingolipids- enriched microdomains on plasma membrane surface of mammal cells, involved in a variety of cellular processes. Depleting cholesterol from the plasma membrane by drugs influences the trafficking of lipid raft markers. Optical imaging techniques are powerful tools to study lipid rafts in live cells due to its noninvasive feature. In this study, breast cancer cells MCF-7 were treated with different concentrations of MβCD to deplete cholesterol and an environmentally sensitive fluorescence probe, Laurdan was loaded to image lipid order by two-photon microscopy. The generalized polarization (GP) values were calculated to distinguish the lipid order and disorder phase. GP images and GP distributions of native and cholesterol-depleted MCF-7 cells were obtained. Our results suggest that even at low concentration (0.5 mM) of MβCD, the morphology of the MCF-7 cells ...
Lipid rafts are densely packed, floating asemblages of cholesterol, sphingolipid and mostly receptor proteins that are present within cell membranes and that function in membrane trafficking and signaling [30]. Among other things, lipid rafts play critical roles in viral entry, replication, assembly and budding, as well as in protein transport [31]. Cholesterol is a key component of lipid rafts that compartmentalize cellular processes. Further, changes in cellular cholesterol levels have been linked to alterations in the infection process of numerous viruses where the cholesterol dissipative agent, MβCD, has been used to evaluate cholesterol-enriched lipid rafts in virus infection. MβCD is a strictly surface-acting agent that rapidly removes cholesterol from the plasma membrane. Some non-enveloped viruses, such as members of Picornaviridae and Reoviridae, are assembled in the cytoplasm and ...
The action of dexamethasone is initiated by, and strictly dependent upon, the interaction of the drug with its receptor followed by its translocation into the nucleus where modulates gene expression. Where the drug localizes at the intranuclear level is not yet known. We aimed to study the localization of the drug in nuclear lipid microdomains rich in sphingomyelin content that anchor active chromatin and act as platform for transcription modulation. The study was performed in non-Hodgkins T cell human lymphoblastic lymphoma (SUP-T1 cell line). We found that when dexamethasone enters into the nucleus it localizes in nuclear lipid microdomains where influences sphingomyelin metabolism. This is followed after 24 h by a cell cycle block accompanied by the up-regulation of cyclin-dependent kinase inhibitor 1A (CDKN1A), cyclin-dependent kinase inhibitor 1B (CDKN1B), growth arrest and DNA-damage 45A (GADD45A), and glyceraldehyde 3-phosphate dehydrogenase (GAPDH) genes and by ...
The mature erythrocyte is a terminally differentiated, nonendocytic cell in nature. Membrane invagination is uncommon in mature healthy erythrocytes. However, these cells are readily invaded by malaria parasites, which involute the red cell1,2 to generate a host-derived parasitophorous vacuolar membrane (PVM). This process is central to the establishment of the blood-stage infection that is responsible for all symptoms and pathologies of this major human disease.3. Recently, we and others have shown that erythrocytes contain detergent-resistant membranes (DRMs).4⇓⇓⇓⇓⇓-10 These highly buoyant, lipid-rich complexes have also been isolated from various other cell types and appear to be enriched for proteins and lipids present in lipid rafts of cellular membranes. The leading definition of membrane rafts suggests that they may consist of small dynamic domains in the plasma ...
New mass spectrometric methodology was employed to characterise the molecular raft lipid composition of TCR signalling plasma membrane domains. These T cell plasma membrane domains were immunoisolated as native (not detergent-treated) plasma membrane fragments [49] using TCR-activating magnetic beads which were conjugated to Jurkat T leukemic cells. These conjugates were homogenised mechanically and native Jurkat plasma membrane fragments bound to the magnetic beads were isolated. The molecular lipid composition of these T cell plasma membrane fragments was quantitatively charted using a mass spectrometry program developed for comprehensive characterisation of membrane lipidomes [50, 51]. Comparison of the molecular lipid composition of these isolated TCR signalling plasma membrane domains with that of immunoisolated control plasma membrane fragments provided the first ...
Natural Killer T (NKT) cells are a subset of mature T lymphocytes which have been shown to play a major role in controlling immune responses. Recently, it has become evident that the antigen receptor expressed by NKT cells recognize glycolipids presented by CD1d, a major-histocompatibility complex class I-like molecule expressed on dendritic cells, monocytes, and a subgroup of B cells. Via recognition of glycolipids by NKT cells, various cytokines are released which influence other cells of the immune system. A synthetic α-galactosylceramide, KRN 7000, was shown to possess anti-tumor and immunostimulatory activities. To further understand the significant biological activities of glycolipids, in this thesis we describe the synthesis of an OCH analogue, α-S-GalCer, and a series of carbohydrate modified analogues of KRN 7000. ^
Lien vers Pubmed [PMID] - 15337781. J. Cell Biol. 2004 Aug;166(5):743-53. Listeria monocytogenes uptake by nonphagocytic cells is promoted by the bacterial invasion proteins internalin and InlB, which bind to their host receptors E-cadherin and hepatocyte growth factor receptor (HGF-R)/Met, respectively. Here, we present evidence that plasma membrane organization in lipid domains is critical for Listeria uptake. Cholesterol depletion by methyl-beta-cyclodextrin reversibly inhibited Listeria entry. Lipid raft markers, such as glycosylphosphatidylinositol-linked proteins, a myristoylated and palmitoylated peptide and the ganglioside GM1 were recruited at the bacterial entry site. We analyzed which molecular events require membrane cholesterol and found that the presence of E-cadherin in lipid domains was necessary for initial interaction with internalin to promote bacterial entry. In contrast, the initial interaction of InlB with HGF-R did not require membrane ...
TY - JOUR. T1 - Intratumoral injection of α-gal glycolipids induces a protective anti-tumor T cell response which overcomes Treg activity. AU - Abdel-Motal, Ussama M.. AU - Wigglesworth, Kim. AU - Galili, Uri. PY - 2009/10/1. Y1 - 2009/10/1. N2 - α-Gal glycolipids capable of converting tumors into endogenous vaccines, have α-gal epitopes (Galα1-3Galβ1-4GlcNAc-R) and are extracted from rabbit RBC membranes. α-Gal epitopes bind anti-Gal, the most abundant natural antibody in humans constituting 1% of immunoglobulins. α-Gal glycolipids insert into tumor cell membranes, bind anti-Gal and activate complement. The complement cleavage peptides C5a and C3a recruit inflammatory cells and APC into the treated lesion. Anti-Gal further opsonizes the tumor cells and targets them for effective uptake by recruited APC, via Fcγ receptors. These APC transport internalized tumor cells to draining lymph nodes, and present immunogenic tumor ...
For further elucidation of the mechanisms involved in cholesterol crystal recognition, we inhibited phagocytosis pharmacologically with cytochalasin D or lantriculin A. We found that these agents inhibited NLRP3 activation by crystals but not by the AIM2 activator poly(dA-dT)·poly(dT-dA) (Fig. 3a and Supplementary Fig. 6a, c, d). To follow the fate of the internalized particles, we analysed macrophages incubated with cholesterol crystals by combined confocal reflection and fluorescence microscopy. Cholesterol crystals induced profound swelling in a fraction of cells (Fig. 3b), as observed for other aggregated materials3, 14. Phagolysosomal membranes contain lipid raft components15, which allowed us to stain the surface of cells with the raft marker choleratoxin B labelled with one fluorescent colour and also to label internal phagolysosomal membranes after cell permeabilization with differently fluorescing choleratoxin B. Indeed, in macrophages that had previously ingested ...
Cell surface proteins major histocompatibility complex (MHC) class I-related chain A (MICA) and UL16-binding proteins (ULBP) 1, 2, and 3 are up-regulated upon infection or tumor transformation and can activate human natural killer (NK) cells. Patches of cross-linked raft resident ganglioside GM1 colocalized with ULBP1, 2, 3, or MICA, but not CD45. Thus, ULBPs and MICA are expressed in lipid rafts at the cell surface. Western blotting revealed that glycosylphosphatidylinositol (GPI)-anchored ULBP3 but not transmembrane MICA, MHC class I protein, or transferrin receptor, accumulated in detergent-resistant membranes containing GM1. Thus, MICA may have a weaker association with lipid rafts than ULBP3, yet both proteins accumulate at an activating human NK cell immune synapse. Target cell lipid rafts marked by green fluorescent protein-tagged GPI also accumulate with ULBP3 at some synapses. Electron microscopy reveals constitutive clusters of ULBP at the cell surface. Regarding a ...
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The Gram-negative bacterium Neisseria meningitidis is a transient commensal of the human nasopharynx, but occasionally causes life-threatening disease. During colonisation of its niche, N. meningitidis has to overcome innate immune defences, including the expression of antimicrobial peptides (AMPs). Meningococcal resistance to the host defence peptide LL-37 was investigated in Papers I and II. The polysaccharide capsule and lipopolysaccharide (LPS) were found to increase LL-37 resistance by inhibiting peptide binding to the bacteria. Further, N. meningitidis responded to sub-lethal doses of LL-37 by an increase in capsule biosynthesis. Intriguingly, adhesion to epithelial cells and tissues protected N. meningitidis from physiological concentrations of LL-37 and two other helical peptides. The protective effect was mediated by RhoA- and Cdc42-dependent host cell signalling and cholesterol-rich membrane microdomains. The host epithelium thus seems to play an active role in AMP ...
The plasma membrane of eukaryotic cells contains nanodomains known as lipid rafts. Cholesterol depletion is a widely used technique for studying lipid rafts and their involvement in cellular processes. Cholesterol depletion has been reported to cause both increased and abolished T cell signaling. The abolished cell signaling upon cholesterol depletion is likely to be caused by substantial cell death as demonstrated by cell viability measurements. We have investigated how cholesterol depletion alters T cell activation by analyzing Jurkat T cells upon extraction of 10, 20, 30, 40 and 50% of total cholesterol using methyl β cyclodextrin (MBCD), a protocol in which cholesterol depletion does not have any adverse effect on cell viability.Upon cholesterol depletion peripheral actin polymerization and aggregation of the lipid raft marker GM1 in the plasma membrane is observed. The aggregation of GM1 upon cholesterol depletion is dependent on ...
TY - JOUR. T1 - Csk-binding protein controls red blood cell development via regulation of Lyn tyrosine kinase activity. AU - Plani-Lam, Janice H. C.. AU - Slavova-Azmanova, Neli S.. AU - Kucera, Nicole. AU - Louw, Alison. AU - Satiaputra, Jiulia. AU - Singer, Peter. AU - Lam, Kong Peng. AU - Hibbs, Margaret L.. AU - Ingley, Evan. PY - 2017/2/1. Y1 - 2017/2/1. N2 - Erythropoiesis is controlled principally through erythropoietin (Epo) receptor signaling, which involves Janus kinase 2 (JAK2) and Lyn tyrosine kinase, both of which are important for regulating red blood cell (RBC) development. Negative regulation of Lyn involves C-Src kinase (Csk)-mediated phosphorylation of its C-terminal tyrosine, which is facilitated by the transmembrane adaptor Csk-binding protein (Cbp). Although Cbp has significant functions in controlling Lyn levels and activity in erythroid cells in vitro, its importance to primary erythroid cell development and signaling has remained unclear. To address this, we assessed ...
TY - JOUR. T1 - P-glycoprotein retains function when reconstituted into a sphingolipid- and cholesterol-rich environment. AU - Modok, Szabolcs. AU - Heyward, Catherine. AU - Callaghan, Richard. PY - 2004/10/1. Y1 - 2004/10/1. N2 - P-glycoprotein (P-gp) appears to be associated within specialized raftlike membrane microdomains. The activity of P-gp is sensitive to its lipid environment, and a functional association hi raft microdomains will require that P-gp retains activity in the microenvironment. Purified hamster P-gp was reconstituted in liposomes comprising sphingomyelin and cholesterol, both highly enriched in membrane microdomains and known to impart a liquid-ordered phase to bilayers. The activity of P-gp was compared with that of proteoliposomes composed of crude egg phosphatidylcholine (unsaturated) or dipalmitoyl phosphatidylcholine (saturated) in the presence or absence of cholesterol. The maximal ...
The compound LaCa2Fe3O8+y, also known as the Grenier phase, is known to undergo an order-disorder transformation (ODT) at high temperatures and oxidation has been observed when the compound is cooled in air after the ODT. In this study, we have synthesized the Grenier compound in air using traditional solid-state reactions and investigated the structure and composition before and after the ODT. Thermal analysis showed that the material undergoes an ODT in both oxygen and argon atmospheres with dynamic, temperature dependent, oxidation upon cooling. Results from scanning transmission electron microscopy (STEM) suggest that the Grenier phase has preferential segregation of Ca and La on the two crystallographic A sites before the ODT, but a random distribution above the ODT temperature. Furthermore, STEM images suggest the possibility that oxygen excess may exist in La-rich regions within microdomains rather than at microdomain boundaries.
Using a combination of in vitro and in vivo experiments and both artificial and natural allergen particles, we have presented evidence that the cross-linking of IgE/FcεRI complexes on MCs by particulate allergens induces not only MC degranulation but also phagocytosis of the activating allergens. Following phagocytosis, the allergens avoid intracellular degradation and acquire the potential for extracellular release. This remarkable phenomenon is directly attributable to lipid raft-mediated phagocytosis of allergen followed by the conversion of allergen-containing phagosomes into secretory compartments within the cells. Evidence that the IgE/FcεRI-mediated MC phagocytosis of particulate allergens involves lipid raft entities comes from the observations that: 1) the phagocytic event is preceded by the association of IgE/FcεRI complexes with lipid rafts; and 2) the disruption of lipid rafts in MCs blocked the phagocytosis of allergens. Lipid rafts have previously been reported ...
A number of reports have shown that CD44 is present in cholesterol-enriched lipid raft microdomains in various cell types including T cells (Ilangumaran et al., 1998; Gómez-Móuton et al., 2001; Oliferenko et al., 1999; Seveau et al., 2001; Pierini et al., 2003; Bourguignon et al., 2004). However, the functional significance of CD44 localization in the lipid rafts had been largely unknown. This study demonstrated the functional significance of this association in T cell adhesion properties. We demonstrated in the present study that cellular cholesterol modulates the HA-binding ability of CD44. Using BW5147 T cells, which express CD44 with HA-binding ability, we showed that cholesterol depletion induced with MβCD upregulates both the HA-binding ability of CD44 (Fig. 1) and the loss of CD44 from detergent-insoluble fractions (Fig. 3). We also found that cholesterol oxidation and sequestration upregulate CD44s HA-binding ability (Fig. 2), suggesting that the ...
Ursodeoxycholic acid (UDCA) is known as a suppressor of cholestatic liver diseases and colorectal cancer development. Here, we demonstrate that UDCA induces apoptosis without necrotic features in SNU601, SNU638, SNU1 and SNU216 human gastric cancer cells, implying its possible use as an effective chemotherapeutic agent in treatment of gastric cancer. UDCA-induced apoptosis was dominantly mediated by an extrinsic pathway dependent on caspase-8, -6 and -3. UDCA increased expression of death receptor 5 [(DR5), also known as tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) receptor 2], and this DR appeared to be responsible for UDCA-induced apoptosis, as evidenced by DR5 knockdown. UDCA triggered formation of lipid rafts that played crucial roles in UDCA-induced apoptotic actions. Lipid rafts were required not only for provision of a proper site for DR5 action but also for mediation of DR5 expression. In addition, reactive oxygen species (ROS) and protein kinase C (PKC) δ appeared to ...
Tryptic peptides were either directly separated on a one-dimensional fused silica capillary column (20 cm × 100 μm) packed with Jupiter resin (3-μm mean particle size, 300 Å pore size; Phenomenex, Torrance, CA, USA) or analyzed by MudPIT.21 One-dimensional liquid chromatography was used with the following gradient at a flow rate of 0.5 μL/min: 0 to 2 minutes: 2% ACN (0.1% formic acid), 2 to 70 minutes: 2% to 35% ACN (0.1% formic acid), 70 to 90 minutes: 35% to 90% ACN (0.1% formic acid) balanced with 0.1% formic acid. The eluate was directly infused into a Velos Pro linear ion trap mass spectrometer (ThermoFisher, San Jose, CA, USA) equipped with a nanoelectrospray source. For MudPIT analysis, peptides were loaded onto a custom packed biphasic C18/SCX trap column (4 cm × 150 μm, Jupiter C18, 5 μm, 300 Å media followed by 4 cm × 150 μm, Luna SCX, 5 μm, 100 Å media; Phenomenex). The trap column was coupled to a capillary analytical column (20 cm × 100 μm, Jupiter C18, 3 μm, 300 Å ...
Paramecium, a ciliate, is an important model for studying Ca2+ signaling and understanding chemoreception and signal transduction. There are several proteins, such as plasma membrane calcium ATPases (PMCAs)/ calcium pumps, SERCA pumps, calmodulin and Ca2+ channels that play an important role in maintaining intracellular Ca2+ level and signaling in Paramecium. Isoform 2 of PMCA has been identified in both the cilia and pellicle membranes of Paramecium, the activity of which leads to hyperpolarization. Plasma and ciliary membrane of Paramecium is made up of a variety of sterols and sphingolipids which constitute lipid rafts, demonstrated by the presence of detergent resistant membranes and their distribution in sucrose and Optiprep density gradients. PMCAs are important markers of lipid rafts and PMCA 2 is found to be localized in lipid rafts of both the cilia and somatic membrane of Paramecium. ...
gB, but not gD or gH/gL, binds to liposomes.Our laboratory previously showed that HSV virions bind to liposomes when incubated in the presence of a soluble form of the gD receptor, HVEM, at pH 5.0 (55). Second, gB730t, but not soluble forms of gD or gC, can bind to cholesterol-rich lipid rafts (10). Together, these data suggest that HSV may interact with lipids through gB. In support of this hypothesis, mutations in the fusion loops of two class II fusion proteins from flavivirus (2) and Semliki Forest virus (35) impair the ability of these proteins to associate with liposomes. Therefore, we theorized that if gB inserts into target membranes via the putative fusion loops, gB730t should associate and float with liposomes, while the soluble forms of the fusion loop mutants should be impaired in this association.. To test this hypothesis, purified soluble gB, gD, and gH/gL were each incubated with two different compositions of liposomes, i.e., PC only or PC/C, at 37°C for 1 h. We then added KCl ...
Crosslinking of Fc epsilon RI on rat basophilic leukemia (RBL 2H3) cells leads to an increase in Phosphatidylinositol 4-kinase activity. This increase in Ptdlns 4-kinase activity is strongly correlated with its tyrosyl phosphorylation state. Characterization of the enzyme activity in anti phosphotyrosine immunoprecipitates suggests it as a type II Ptdlns 4-kinase. Membrane cholesterol depletion studies showed a reduction in type II Ptdlns 4-kinase activity suggesting that lipid rafts play an important role in activation of the enzyme. The enzyme activity was inhibited by resveratrol. In situ inhibition of type II Ptdlns 4-kinase activity showed a reduction in beta-hexosaminidase release upon Fc epsilon RI cross-linking. These studies suggest that a type II Ptdlns 4-kinase is an integral component of Fc epsilon RI mediated signal transduction mechanisms. (c) ...
Doharty et al. (40) described previously the presence of platelet GP Ibα in rafts, but did not characterize this further. Because of our interest in the signaling functions of the GP Ib-IX-V complex, and because of the conspicuous presence of palmitate on two of its subunits, we investigated the role of raft localization in GP Ib-IX-V complex function. On sucrose density fractions of 1% Triton X-100 platelet lysates, a significant portion of the GP Ib-IX-V complex could be found in the early fractions (fractions 3-5), as determined by immunoprecipitation and immunoblotting for GP Ibα (Fig. 1 A, top). Upon platelet activation with ristocetin/human VWF, the amount of GP Ib-IX-V complex in these fractions increased approximately threefold (Fig. 1 A, middle). We confirmed that the GP Ib-IX-V complex found in the early fractions was localized in lipid rafts by staining the fractions for the raft marker ganglioside GM1, which also appeared predominantly in fractions 3-5 (Fig. 1 B, third panel). ...
TY - JOUR. T1 - Cell confluence induces switching from proliferation to migratory signaling by site-selective phosphorylation of PDGF receptors on lipid raft platforms. AU - Szöor, Árpád. AU - Ujlaky-Nagy, László. AU - Tóth, Gábor. AU - Szöllosi, János. AU - Vereb, György. PY - 2016/2/1. Y1 - 2016/2/1. N2 - Platelet derived growth factor receptors (PDGFR) play an important role in tumor pathogenesis and are frequently overexpressed in glioblastoma. Earlier we have shown that only confluent glioblastoma cell cultures exhibit a biphasic calcium transient upon PDGF stimulation. Here, we examined how the change in cell density leads to differential cellular responses to the same PDGF stimulus. PDGF beta receptors and their specific phosphotyrosine residues were fluorescently co-labeled on A172 and T98G glioblastoma cells. The distribution in cell membrane microdomains (lipid rafts) and the phosphorylation state of PDGFR was measured by confocal microscopy and ...
A recent study has shown that Cr-1 controls processing of the Nodal proprotein by recruiting proprotein convertases such as furin or PACE4 (Blanchet et al., 2008). Because processing by furin-like convertases (S1 cleavage) is also a prerequisite to generate mature heterodimerized Notch receptors (Logeat et al., 1998), we hypothesized that CR-1 may affect this processing step. Similar to the sequestration of the Nodal precursor protein into lipid rafts (Blanchet et al., 2008), forced expression of CR-1 in CR-1-deficient CHO cells enhanced the localization of the FL Notch1 protein in the lipid raft fraction in which glycosylphosphatidylinositol-anchored proteins such as CR-1 are enriched (Fig. 4 B). Furthermore, we assessed the effect of CR-1 expression on S1 cleavage of Notch1 in the presence of the γ-secretase inhibitor DAPT to exclude the effect on ligand-induced S3 cleavage (Fig. 4, C and D). CR-1 expression caused a dose-dependent increase in enhancement of the cleaved form of Notch1. ...
PAG (phosphoprotein associated with GEMs), also known as Cbp (Csk-binding protein), is a ubiquitously expressed 46 kDa transmembrane adaptor protein present in membrane rafts (glycosphingolipid-enriched microdomains), which however migrates on SDS PAGE gels anomalously as an 80 kDa molecule. Following tyrosine phosphorylation by Src family kinases, PAG binds and thereby activates the protein tyrosine kinase Csk, the major negative regulator of the Src family kinases. Signaling via the B-cell receptor in B cells or high affinity IgE receptor (FcepsilonRI) in mast cells leads to PAG increased tyrosine phosphorylation and Csk binding, while T cell receptor signaling causes PAG dephosphorylation, loss of Csk binding and increased activation of the protein tyrosine kinase Lck ...
PAG (phosphoprotein associated with GEMs), also known as Cbp (Csk-binding protein), is a ubiquitously expressed 46 kDa transmembrane adaptor protein present in membrane rafts (glycosphingolipid-enriched microdomains), which however migrates on SDS PAGE gels anomalously as an 80 kDa molecule. Following tyrosine phosphorylation by Src family kinases, PAG binds and thereby activates the protein tyrosine kinase Csk, the major negative regulator of the Src family kinases. Signaling via the B-cell receptor in B cells or high affinity IgE receptor (FcepsilonRI) in mast cells leads to PAG increased tyrosine phosphorylation and Csk binding, while T cell receptor signaling causes PAG dephosphorylation, loss of Csk binding and increased activation of the protein tyrosine kinase Lck ...
Precise regulation of free intracellular Ca2+ concentrations [Ca2+]i is critical for normal neuronal function, and alterations in Ca2+ homeostasis are associated with brain aging and neurodegenerative diseases. One of the most important proteins controlling [Ca2+]i is the plasma membrane Ca2+-ATPase (PMCA), the high affinity transporter that fine tunes the cytosolic nanomolar levels of Ca2+. We previously found that PMCA protein in synaptic plasma membranes (SPMs) is decreased with advancing age and the decrease in enzyme activity is much greater than that in protein levels. In the present study, we isolated raft and non-raft fractions from rat brain SPMs and used quantitative mass spectrometry to show that the specialized lipid microdomains in SPMs, the rafts, contain 60% of total PMCA, comprised of all four isoforms. The raft PMCA pool had the highest specific activity and this decreased progressively with age. The reduction in PMCA ...
Abstract: The control of lipid domain formation in biological membranes has received limited consideration. This mechanism is quantitatively investigated using Monte Carlo computer simulations of a simple model system. Monte Carlo simulations are performed on a simple model system composed of phosphatidylecholine (PC), phosphatidylserine (PS), and cholesterol (Chol). Domain formation induced by binding of the phospholipid binding proteins, annexin A5 (A5) and the C2 protein motif is investigated. Simulations for models containing PC/PS lipids indicate that the addition of A5 does not induce lipid domain formation while binding of C2 greatly induces lipid domain formation. The addition of Chol to PC/PS systems was found to induce lipid demixing in the absence and presence of A5 and further enhance the ability of C2 to form PS domains. Incorporation of a preferential protein-protein interaction to PC/PS and PC/PS/Chol systems was found to further increase lipid demixing for all compositions. ...
and forskolin-stimulated AC activity is increased by caveolin-1 knockdown or knockout, the results suggest that noninvolvement of Gαi or a GPCR coupled to Gαi. Alternatively, because caveolin-1 is a cholesterol-binding protein (Murata et al., 1995), limiting its expression could lower membrane cholesterol. This is not the case (Fig. 5). In fact, incubating wild-type or Cav-1 RNAi cells with 1 mg/ml exogenous cholesterol significantly decreased isoproterenol-stimulated cAMP accumulation (Fig. 5). Thus, removing membrane cholesterol does seem to enhance βAR/Gαs/adenylyl cyclase signaling (most likely by disrupting rafts/caveolae), and adding cholesterol has the opposite effect. Therefore, the elevated cAMP signaling due to loss of caveolin is independent of Gαi and cholesterol levels.. Lipid rafts/caveolae can influence both spatial organization at the membrane and intracellular trafficking of signaling molecules; both mechanisms could ...
Phospholipase D2 (PLD2) has been found localized in low-density caveolin-rich membrane microdomains. Our previous study suggested that PLD2 and aquaporin 3 (AQP3) interact in these domains to inhibit keratinocyte proliferation and promote differentiation by cooperating to produce phosphatidylglycerol. To examine the effect of membrane microdomain localization on the PLD2/AQP3 signaling module and keratinocyte proliferation and differentiation, we treated mouse keratinocytes with 3 µM cell-permeable caveolin-1 scaffolding domain peptide or a negative control peptide and stimulated cell differentiation using a moderately elevated extracellular calcium concentration (125 uM) to maximally promote differentiation and phosphatidylglycerol production. Cell proliferation, differentiation, total PLD activity, phosphatidylglycerol levels, and AQP3 activity were monitored. The caveolin-1 scaffolding domain peptide itself had no effect on ...
Rationale: Cyclic nucleotides are second messengers that regulate cardiomyocyte function through compartmentalized signaling in discrete subcellular microdomains. However, the role of different microdomains and their changes in cardiac disease are not well understood. Objective: To directly visualize alterations in β-adrenergic receptor (β-AR)-associated 3,5-cyclic adenosine (cAMP) and guanosine (cGMP) microdomain signaling in early cardiac disease. Methods and Results: Unexpectedly, measurements of cell shortening revealed augmented βAR-stimulated cardiomyocyte contractility by atrial natriuretic peptide (ANP)/cGMP signaling in early in cardiac hypertrophy following transverse aortic constriction, which was in sharp contrast to well-documented β-adrenergic and natriuretic peptide signaling desensitization during chronic disease. Real-time cAMP analysis in β1- and β2-AR-associated membrane microdomains using a novel ...
Abstract: Low molecular weight protein tyrosine phosphatases (LMW-PTPs) are small enzymes that are ubiquitous in many organisms. They are important in biological processes such as cell proliferation, adhesion, migration, and invasiveness. LMW-PTP is expressed in mammalian cells as two isoforms (IF1 and IF2) originating through alternative splicing. We have previously shown that IF2 targets lipid rafts called caveolae and interacts with caveolin-1, their major structural protein. Caveolae are cholesterol- and sphingolipid-rich membrane microdomains that have been implicated in a variety of cellular functions, including signal transduction events. Caveolin-1 contains a scaffolding region that contributes to the binding of the protein to the plasma membrane and mediates protein omo- and etero-oligomerization. Interaction of many signaling molecules with the scaffolding domain sequesters them into caveolae and inhibits or ...
CD1d-restricted natural killer T cells (NKT cells) possess a wide range of effector and regulatory activities that are related to their ability to secrete both T helper 1 (Th1) cell- and Th2 cell-type cytokines. We analyzed presentation of NKT cell activating α galactosylceramide (αGalCer) analogs that give predominantly Th2 cell-type cytokine responses to determine how ligand structure controls the outcome of NKT cell activation. Using a monoclonal antibody specific for αGalCer-CD1d complexes to visualize and quantitate glycolipid presentation, we found that Th2 cell-type cytokine-biasing ligands were characterized by rapid and direct loading of cell-surface CD1d proteins. Complexes formed by association of these Th2 cell-type cytokine-biasing αGalCer analogs with CD1d showed a distinctive exclusion from ganglioside-enriched, detergent-resistant plasma membrane microdomains of antigen-presenting cells. These findings help to explain how ...
Successful infection by influenza virus requires that the envelope spike protein, hemagglutinin (HA), catalyzes fusion between the viral envelope and the intracellular endosomal membrane of the target cell and creates a pore large enough to release the viral genome. There is a growing appreciation that membrane lipids play a role in this critical event, coming mostly from experiments and theory on lipid composition in relationship to membrane monolayer curvature stress (Markin et al., 1984; Kozlov et al., 1989; Chizmadzhev et al., 1995; Chernomordik, 1996; Siegel, 1999; Kuzmin et al., 2001; Kozlovsky and Kozlov, 2003; Chernomordik et al., 2006). Recently there has been consideration given to the role of membrane phase behavior and membrane microdomains on the lateral distribution, sorting, and interactions of lipids with membrane proteins in general, and viral envelope ...
Human rhinovirus (HRV) infections are major contributors to the healthcare burden associated with acute exacerbations of chronic airway disease, such as chronic obstructive pulmonary disease and asthma. Cellular responses to HRV are mediated through pattern recognition receptors that may in part signal from membrane microdomains. We previously found Toll-like receptor signaling is reduced, by targeting membrane microdomains with a specific liposomal phosphatidylserine species, 1-stearoyl-2-arachidonoyl-sn-glycero-3-phospho-L-serine (SAPS). Here we explored the ability of this approach to target a clinically important pathogen. We determined the biochemical and biophysical properties and stability of SAPS liposomes and studied their ability to modulate rhinovirus-induced inflammation, measured by cytokine production, and rhinovirus replication in both immortalized and normal primary bronchial epithelial cells. SAPS liposomes ...
Caveolae are plasma membrane microdomains that localise receptors and signalling intermediates within an environment where they can efficiently trigger downstream events. While present in most cells types, they are particularly abundant in vascular smooth muscle cells and endothelial cells (ECs), where they regulate low density lipoprotein trans-cytosis, NO production and inflammation. Cavin-1 is a protein required for caveolae maturation, such that its deletion results in no detectable caveolae and the down-regulation of "caveolin" scaffolding proteins. However, the cellular processes regulating cavin-1 function are poorly understood. Proteomic screening and biochemical experiments have identified cavin-1 as a novel interacting protein of the cytokine-inducible E3 ubiquitin ligase component "suppressor of cytokine signalling-3" (SOCS3), a key inhibitor of IL-6-mediated pro-inflammatory signalling in ECs. We hypothesise d that the ...
The TRPC (transient receptor potential canonical) proteins are activated in response to agonist-stimulated PIP2 (phosphatidylinositol 4,5-bisphosphate) hydrolysis and have been suggested as candidate components of the elusive SOC (store-operated calcium channel). TRPC1 is currently the strongest candidate component of SOC. Endogenous TRPC1 has been shown to contribute to SOCE (store-operated calcium entry) in several different cell types. However, the mechanisms involved in the regulation of TRPC1 and its exact physiological function have yet to be established. Studies from our laboratory and several others have demonstrated that TRPC1 is assembled in a signalling complex with key calcium signalling proteins in functionally specific plasma membrane microdomains. Furthermore, critical interactions between TRPC1 monomers as well as interactions between TRPC1 and other proteins determine the surface expression and function of TRPC1-containing channels. Recent studies have ...
Lipid rafts enriched in glycosphingolipids (GSLs), cholesterol and signaling molecules play an essential role not only for signal transduction started by ligand binding, but for intracellular events such as organization of actin, intracellular traffic and cell polarity, but their functions in cleavage division of preimplantation embryos are not well known. Here we show that monosialylGb5Cer (MSGb5Cer)-enriched raft domains are involved in development during the cleavage stage of mouse preimplantation embryos. MSGb5Cer preferentially localizes at the interfaces between blastomeres in mouse preimplantation embryos. Live-imaging analysis revealed that MSGb5Cer localizes in cleavage furrows during cytokinesis, and that by accumulating at the interfaces, it thickens them. Depletion of cholesterol from the cell membrane with methyl-beta-cyclodextrin (MbCD) reduced the expression of MSGb5Cer and stopped cleavage. Extensive ...
Title: Cholesterol, Lipids, Amyloid Beta, and Alzheimers. VOLUME: 7 ISSUE: 3. Author(s):M. Vestergaard, T. Hamada, M. Morita and M. Takagi. Affiliation:School of Materials Science, JAIST, 1-1 Asahidai, Nomi City, Ishikawa, 923-1292, Japan.. Keywords:Alzheimers disease, cholesterol, lipids, amyloid beta, amyloid precursor protein, lipid raft domains, membrane, lipid vesicles. Abstract: High levels of cholesterol have been proposed as a risk factor for Alzheimers disease (AD). Polymorphism of genes encoding proteins that regulate cholesterol metabolism have also been associated with the frequency of Alzheimers development. Some studies have shown that cholesterol-lowering drugs reduce the frequency of AD development. The proposed role of cholesterol in AD has been challenged by several studies. In this review, we provide a brief account of the major pieces of evidence in support of and against the possible role of cholesterol in the development of AD, and the methodologies used. We highlight ...
A time-resolved fluorescence anisotropy imaging method for studying nanoscale clustering of proteins or lipids was developed and evaluated. It is based on FRET between the identical fluorophores (homo-FRET), which results in a rapid depolarization of the fluorescence. The method employs the time-resolved fluorescence anisotropy decays recorded in a confocal microscope equipped with pulsed excitation and time-gated detection. From the decay the limiting anisotropy r inf was derived, which is a direct measure for the number of fluorophores per cluster. The method was evaluated by imaging GPI-GFP, a lipid raft marker. Small clusters were observed in the plasma membrane while the cytoplasm and the Golgi contained predominantly monomers.. ©2007 Optical Society of America. Full Article , PDF Article ...
Natures fastest motors are the cochlear outer hair cells (OHCs). These sensory cells use a membrane protein, Slc26a5 (prestin), to generate mechanical force at high frequencies, which is essential for explaining the exquisite hearing sensitivity of mammalian ears. Previous studies suggest that Slc26a5 continuously diffuses within the membrane, but how can a freely moving motor protein effectively convey forces critical for hearing? To provide direct evidence in OHCs for freely moving Slc26a5 molecules, we created a knockin mouse where Slc26a5 is fused with YFP. These mice and four other strains expressing fluorescently labeled membrane proteins were used to examine their lateral diffusion in the OHC lateral wall. All five proteins showed minimal diffusion, but did move after pharmacological disruption of membrane-associated structures with a cholesterol-depleting agent and salicylate. Thus, our results demonstrate that OHC lateral wall ...
The precise regulation of intestinal epithelial TJs is crucial to maintaining barrier function between the luminal milieu and the internal environment. Recent studies have revealed an important role for Rho GTPases in regulating TJ structure/function (22, 29). In particular, TJ strand organization has been shown to be altered by constitutively active RhoA and Rac1 mutants (22) and inactivation of GTPases by C. difficile toxins is known to cause redistribution of occludin and ZO-1 from membrane microdomains or membrane rafts (32). As a result, we have further explored the mechanisms whereby paracellular permeability is influenced by this family of mediators and investigated whether the inactivation of a single GTPase (RhoA, Rac1, or Cdc42) has an effect on TJ distribution in such membrane rafts and whether TJ proteins involved in strand formation (such as claudin-1 and -2) are altered in this setting.. Using MDCK cell lines ...
Dextrallorphan (DXA) is an opioid derivative chemical of the morphinan class that is used in scientific research. It acts as a σ1 receptor agonist and NMDA receptor antagonist. It has no significant affinity for the σ2, μ-opioid, or δ-opioid receptor, or for the serotonin or norepinephrine transporter. As an NMDA receptor antagonist, in vivo, it is approximately twice as potent as dextromethorphan, and five-fold less potent than dextrorphan. Dextrallorphan is often used in research to block σ1 receptor sites so that σ2 receptor sites (which have not been cloned yet) can be studied. It was hypothesized that both of these sigma (σ) receptors were opioid receptors, due to their affinity for psychoactive drugs. However, it is now understood that they are non-opioid receptors that bind to certain psychoactive drugs, like dextrallorphan. One example of dextrallorphan being used to mask σ1 receptor sites was seen in a study on the localization of the σ2 receptor in detergent-resistant lipid ...
Kallikreins are secreted proteases that may play a functional role and/or serve as a serum biomarker for the presence or progression of certain types of cancers. Kallikrein 6 (KLK6) has been shown to be upregulated in several types of cancers, including colon. The aims of this study were to elucidate pathways that influence KLK6 gene expression and KLK6 protein secretion in the HCT116 human colon cancer cells. Our data indicate a central role for caveolin-1 (CAV-1), the main structural protein of caveolae, in both KLK6 gene expression and protein secretion. Sucrose gradient subcellular fractionation reveals that CAV-1 and KLK6 colocalize to lipid raft domains in the plasma membrane of HCT116 cells. Furthermore, we show that CAV-1, although it does not directly interact with the KLK6 molecule, enhances KLK6 secretion from the cells. Deactivation of CAV-1, through SRC-mediated phosphorylation, decreased KLK6 secretion. We also demonstrate that, in colon cancer cells, CAV-1 ...
Adherent and invasive Escherichia coli (AIEC) associated with Crohns disease are able to survive and to replicate extensively in active phagolysosomes within macrophages. AIEC-infected macrophages release large amounts of tumour necrosis factor-alpha (TNF-α) and do not undergo cell death. The aim of the present study was to determine what benefit AIEC bacteria could gain from inducing the release of large amounts of TNF-α by infected macrophages and to what extent the neutralization of TNF-α could affect AIEC intramacrophagic replication. Our results showed that the amount of TNF-α released by infected macrophages is correlated with the load of intramacrophagic AIEC bacteria and their intracellular replication. TNF-α secretion was not related to the number of bacteria entering host cells because when the number of bacteria internalized in macrophage was decreased by blocking lipid raft-dependent and clathrin-coated pits-dependent endocytosis, the amount of TNF-α secreted by infected ...
Important discoveries in the last decades have changed our view of the plasma membrane organisation. Specifically, the cortical cytoskeleton has emerged as a key modulator of the lateral diffusion of membrane proteins. Cytoskeleton-dependent compartmentalised lipid diffusion has been proposed, but this concept remains controversial because this phenomenon has thus far only been observed with artefact-prone probes in combination with a single technique: single particle tracking. In this paper, we report the first direct observation of compartmentalised phospholipid diffusion in the plasma membrane of living cells using a minimally invasive, fluorescent dye labelled lipid analogue. These observations were made using optical ...
Aim: Heating by nanoparticles, which are located in the tissue to be treated, is a well-recognized method in hyperthermic oncology. Our objective is to investigate selective, nanoscopic heating without concentrating extra artificial nanoparticles. We have in silico calculation to study the heating of the transmembrane protein clusters (rafts) on cell-membrane. The transmembrane protein domains have significantly higher dielectric constant than their lipid neighborhood in the membrane. This difference causes a local gradient in the Specific Absorption Rate (SAR), which could be a factor of heating of the membranes locally, as well as exciting the receptors for various signal transduction in the cells. We suppose that this process determines the observed cellular effects of modulated electro-hyperthermia (mEHT, trade-name: oncothermia). Materials and Methods: In silico models with highly specialized software ...
Malignant gliomas represent a difficult therapeutic challenge due to the invasive nature of the tumor and limited tumoral delivery of therapeutic agents. In this study, novel nano liposome carriers composed of sulfatides were developed for the glioma targeted delivery. Firstly, sulfatides-containing liposomes (SCLs) were found to interact with glioma cells specifically. The specific interactions between sulfatides and tenascin-c (TN-C), a glioma overexpressed protein, may have an important role. Secondly, the mechanism of intracellular delivery of SCLs was studied. SCLs were found to be effectively internalized in glioma cells by both clathrin-dependent and caveolae/lipids rafts pathways. Thirdly, doxorubicin (DOX) was effectively loaded into the SCLs to form a liposomal drug, SCL-DOX. SCL-DOX could effectively accumulate in the nuclei of glioma cells that resulted in superior in vitro cytotoxicity. In a subcutaneous xenografts animal model, SCL-DOX could effectively inhibit tumor growth and ...
The Editors wish to note that a reader has raised questions about the integrity of certain figures in the foregoing articles listed below. We have been informed by Emory University of an ongoing review conducted by an inquiry committee at the University. We are awaiting the findings of the committee to determine the appropriate next steps.. 1) Zuo L, Ushio-Fukai M, Ikeda S, Hilenski L, and Alexander RW. Microtubules regulate angiotensin II type receptor and rac 1 localization in caveolae/lipid rafts: role in redox signaling. Arterioscler Thromb Vasc Biol. 2004;24:1223-1228.. 2) Zuo L, Ushio-Fukai M, Ikeda S, Hilenski L, Patrushev N, Alexander RW. Caveolin-1 is essential for activation of rac 1 and NAD(P)H oxidase after angiotensin II type 1 receptor stimulation in vascular smooth muscle cells: role in redox signaling and vascular hypertrophy. Arterioscler Thromb Vasc Biol. 2005;25;1824-1830.. ...
Understanding how cell adhesion proteins form adhesion domains is a key challenge in cell biology. Here, we use single-molecule atomic force microscopy (AFM) to demonstrate the force-induced formation and propagation of adhesion nanodomains in living fungal cells, focusing on the covalently anchored cell-wall protein Als5p from Candida albicans. We show that pulling on single adhesins with AFM tips terminated with specific antibodies triggers the formation of adhesion domains of 100-500 nm and that the force-induced nanodomains propagate over the entire cell surface. Control experiments (with cells lacking Als5p, single-site mutation in the protein, bare tips, and tips modified with irrelevant antibodies) demonstrate that Als5p nanodomains result from protein redistribution triggered by force-induced conformational changes in the initially probed proteins, rather than from nonspecific cell-wall perturbations. Als5p remodeling is independent of cellular metabolic activity because heat-killed ...
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The files in this directory incorporate calcium handling mechanisms involved in the Ca - Calmodulin - CaMKII - PP1 pathway in a conductance-based neuronal CA1 pyramidal model developed in Rathour and Narayanan, PNAS, 2014. The simulation environment is NEURON. The model contains Na, KDR, KA, h, CaT and CaR currents, and employs GHK-based implementations of AMPA and NMDA receptors. Fig13.hoc helps recreate Fig 13 of the following paper: Basak R, Narayanan R. Active dendrites regulate the spatiotemporal spread of signaling microdomains; Plos Comp Biol (in Press). Running Fig13.hoc will create files that will contain .txt files storing the values of various species (Ca, Calmodulin, phosphorylated CaMKII etc.) as they evolve with time at various spatial locations, specifically the 100 µm length around the spine-containing synapse in the oblique containing the calcium handling mechanisms. The default number of spines in the oblique in the .hoc file is 1000. Example output was obtained by running ...
To investigate the role of the coreceptor CD8 and lipid rafts in cytotoxic T lymphocyte (CTL) activation, we used soluble mono-and multimeric H-2K,sup,d,/sup,-peptide complexes and cloned S14 CTL specific for a photoreactive derivative of the Plasmodium berghei circumsporozoite (PbCS) peptide 252-260 [PbCS(ABA)]. We report that activation of CTL in suspension requires multimeric K,sup,d,/sup,-PbCS(ABA) complexes co-engaging TCR and CD8. Using TCR ligand photo-cross-linking, we find that monomeric K,sup,d,/sup,-PbCS(ABA) complexes promote association of TCR/CD3 with CD8/p56,sup,lck,/sup,. Dimerization of these adducts results in activation of p56lck in lipid rafts, where phosphatases are excluded. Additional cross-linking further increases p56,sup,lck,/sup, kinase activity, induces translocation of TCR/CD3 and other signaling molecules to lipid rafts and intracellular calcium mobilization. These events are prevented by blocking Src kinases or CD8 binding to TCR-associated K,sup,d,/sup, ...
As a forum for professional feedback, submissions of letters are open to all. You do not need to be a subscriber. To avoid redundancy, we urge you to read other peoples letters before submitting your own. Name, current appointment, place of work, and email address are required to send a letter, and will be published with your review. We also require that you declare any competing financial interests. Unprofessional submissions will not be considered or responded to.. ...
Instant membrane resealing importantly contributes to the functional and structural integrity of the endothelial cells (ECs) that are exposed to various physical and chemical stimuli in blood stream. The present study was designed to explore the molecular mechanisms mediating this endothelial membrane resealing with a focus on the role of lipid rafts (LR) clustering. Using high energy Laser gun, a tiny hole was made in cultured EC bathed with FM1-43, and the rapid entry of this FM1-43 to produce fluorescence was used to measure membrane resealing. We demonstrated that ECs exhibited a Ca2+-dependent instant membrane resealing, as shown by a significant reduction of fluorescence appearance within these cells compared to ECs bathed with Ca2+ free solution. This Ca2+-dependent instant membrane resealing was also observed in ECs up stimulation of Lactobacillus casei cell wall fragments (LCWE), which was commonly used to produce ...
Watts, Tim (2010) Comparative effect of haemodynamic variables and rheological properties of the blood on the margination and adhesion of leukocytes and platelets. Ph.D. thesis, University of Birmingham.. Jeffery, Hannah Claire (2012) Determining the functional impact of KSHV infection of endothelial cells. Ph.D. thesis, University of Birmingham.. Langan, Stacey Anne (2011) Does crosslinking of podoplanin by CLEC-2 inhibit migration of lymphatic endothelial cells? & Regulation of the platelet collagen receptor GPVI and its sheddase ADAM10 by tetraspanin membrane microdomains. M.Res. thesis, University of Birmingham.. Petrovic, Kristina (2014) Hepatitis C transmission using lymphocytes as vectors: mechanism and therapeutic interventions and Neutrophil recruitment to microvascular endothelium: the impact of mesenchymal stem cells. M.Res. thesis, University of Birmingham.. Pankhurst, Tanya (2010) Heterogeneity of injury in vasculitis: influence of anti neutrophil cytoplasm ...
In this study, we show a novel and essential role of SMS2 in modulating NFκB activation. This is based on the following observations: in both SMS2 KO mouse macrophages and SMS2 knockdown HEK293 cells, (1) SMS activity, de novo SM synthesis, cellular and plasma membrane SM levels were significantly decreased, (2) ligand-induced NFκB activation, including IκBα degradation and NFκB nuclear translocation, as well as transcriptional activation, were significantly attenuated, and (3) LPS-induced membrane recruitment of TLR4-MD2 complex and TNF-α-induced raft association of TNFR1 were impaired in SMS2 KO macrophages and SMS2 siRNA-treated HEK293 cells, respectively.. SMS2 makes an important contribution to the de novo SM biosynthesis and total cellular SM levels. Based on their relative proximity to the site of ceramide biosynthesis, it has been suggested that SMS1 might be involved in the de novo SM biosynthesis whereas SMS2 is involved in the ...
Aim: Heating by nanoparticles, which are located in the tissue to be treated, is a well-recognized method in hyperthermic oncology. Our objective is to investigate selective, nanoscopic heating without concentrating extra artificial nanoparticles. We have in silico calculation to study the heating of the transmembrane protein clusters (rafts) on cell-membrane. The transmembrane protein domains have significantly higher dielectric constant than their lipid neighborhood in the membrane. This difference causes a local gradient in the Specific Absorption Rate (SAR), which could be a factor of heating of the membranes locally, as well as exciting the receptors for various signal transduction in the cells. We suppose that this process determines the observed cellular effects of modulated electro-hyperthermia (mEHT, trade-name: oncothermia). Materials and Methods: In silico models with highly specialized software ...
SUMMARY: DR. REGGIE EDGERTON The Spinal Cord Injury Project Summer Open House Thursday, 20 July 2017 This is a synopsis of Dr. Edgerton?s presentation to the W. M. Keck Center Summer Open House. Additional details on his research are available on his website. With appreciation to the students who took notes during Dr. Edgerton?s presentation at the Summer Open House. At the invitation of the W. M. Keck Center for Collaborative Neuroscience and the Spinal Cord Injury Project, Dr.
X Factor duo Reggie N Bollie faced some drama in the run-up to this weekends live final, in an incident which reportedly saw their wives coming to blows. READ MORE: Sick Louisa Could Miss The X...
Reggie Games is raising funds for ELO Darkness on Kickstarter! Complete customizable strategy card game including 600+ cards, a 3-Lane MOBA inspired gameboard and custom miniatures
Close The Infona portal uses cookies, i.e. strings of text saved by a browser on the users device. The portal can access those files and use them to remember the users data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser. ...
A lazy river is a water ride found in water parks, hotels, resorts, and recreation centers, which usually consists of a shallow (2½ ft. to 3½ ft.) pool that flows similarly to a river. There is generally a slow current, usually just enough to allow guests to gently ride along lying on rafts. There may also be scenic elements added, such as small waterfalls on the edge of the river. Some lead into wave pools, while some just go around in circles. A torrent river, or wave river, is a related concept. Torrent rivers feature wave machines similar to those that are in wave pools; the waves then push riders (who are on rafts, as they are in a regular lazy river) around the river faster than they would be traveling in a regular lazy river. Torrent rivers appear at all of the Schlitterbahn water parks and Aquaventure in Dubai and the Bahamas. Most have a policy of no swimming-everybody must ride in a tube. A current channel is another water feature found in aquatic facilities that uses moving water ...
TY - JOUR. T1 - Global analysis of osteosarcoma lipidomes reveal altered lipid profiles in metastatic versus nonmetastatic cells. AU - Roy, Jahnabi. AU - Dibaeinia, Payam. AU - Fan, Timothy M. AU - Sinha, Saurabh. AU - Das, Aditi. PY - 2019/1/1. Y1 - 2019/1/1. N2 - Osteosarcoma (OS) is the most common form of primary bone cancer in humans. The early detection and subsequent control of metastasis has been challenging in OS. Lipids are important constituents of cells that maintain structural integrity that can be converted into lipid-signaling molecules and are reprogrammed in cancerous states. Here, we investigate the global lipidomic differences in metastatic (143B) and nonmetastatic (HOS) human OS cells as compared with normal fetal osteoblast cells (FOB) using lipidomics. We detect 15 distinct lipid classes in all three cell lines that included over 1,000 lipid species across various classes including phospholipids, sphingolipids and ceramides, glycolipids, and cholesterol. We identify a ...
We will discuss the physics that governs the lipid localization and domain formation in multicomponent lipid bilayers coupled to an elastic substrate. Lipid localization and domain formation has been studied extensively in biological cell membranes. In this talk we will extend a previous model for membrane energetics to account for the coupling between the bending and the local lipid composition of the two leaflets. Our aim is to determine the relationship between the localization and domain formation in the presence of lipid flip-flops between the two leaflets and the effect of intrinsic curvature of the lipids. Using a lattice model for the membrane, we simulate the system and study the effect of lipid flip-flop on lipid organization in the membrane. To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2012.MAR.B41.15. ...
The human lipidome comprises over tens of thousands of distinct lipid species in addition to total cholesterol and the other conventional lipid traits that are routinely measurable in the peripheral circulation. Of the lipid species considered to exhibit bioactive functions, sphingolipids are a class of molecules that have shown relevance to human disease risk and cardiovascular outcomes in particular. In this issue of the JCI, Poss et al. conducted targeted lipidomics in a case-control study involving over 600 individuals and found a sphingolipid profile that predicted coronary artery disease status. In the context of emerging evidence linking sphingolipid biology with cardiovascular pathophysiology, these results suggest the potential utility of serum sphingolipids as cholesterol-independent markers of risk and even future targets for optimizing cardiovascular health.. ...
5365 Sphingolipid metabolizing enzymes control the dynamic balance of the cellular levels of bioactive lipids including the proapoptotic compound ceramide and the proliferative compound sphingosine 1-phosphate. Accumulating evidence indicates that sphingosine kinase (SK) plays a pivotal role in regulating tumor growth, and that SK can act as an oncogene. In spite of the importance of SK for cell proliferation, pharmacological inhibition of SK is an untested means of treating cancer due to the current lack of non-lipid inhibitors of this enzyme. Novel inhibitors of human SK were identified from a small molecule screen and several representative compounds were characterized in detail. The SK inhibitors were antiproliferative toward a panel of tumor cell lines, including lines with the multidrug resistance phenotype due to overexpression of either P-glycoprotein or MRP1, and were shown to inhibit endogenous human SK activity in intact cells. Antitumor activity in vivo was detected in the ...
Cell-permeable. SKI-II is selective a non-lipid sphingosine kinase (SK) inhibitor. It displays non-ATP-competitive inhibition of human recombinant GST-SK 1 with an IC50 v
Jean Davignon has been Director of the Hyperlipidemia and Atherosclerosis Research Unit at the Institut de recherches cliniques de Montréal (IRCM) from 1967 until 2008. Emeritus Physician at the Hôtel-Dieu Hospital in Montreal, Professor at the Faculty of Medicine at the Université de Montréal and Adjunct Professor in the Department of Experimental Medicine at McGill University, he was appointed Emeritus Researcher at the IRCM in 2009. He practices in the field of lipidology at the Nutrition, Metabolism and Atherosclerosis Clinic he founded at IRCM in 1967.. His research focuses on the characterization, pathogenesis and treatment of hereditary dyslipidemias, on the atherogenic potential of plasma lipid and non-lipid biomarkers and the role of gene-gene and gene-environment interactions in the causation of cardiovascular diseases. His work encompassing nutritional, genetic, metabolic, pharmacogenomic and molecular aspects has resulted in the publication of 363 scientific papers, 64 book ...
Recent studies such as the JUPITER trial, which showed a beneficial effect on cardiovascular risk from the management of inflammation, not lipids, have shown just how critical non-lipid factors are to cardiovascular health. Many of our patients are at risk for cardiovascular disease and…. ...
GeneJuice® Transfection Reagent Non-lipid based chemical transfection reagent optimized for maximum transfection efficiency, ease-of-use, and minimal cytotoxicity on a wide variety of mammallian cells. - Find MSDS or SDS, a COA, data sheets and more information.
I love being the enemy by Reggie Miller; 1 edition; First published in 1995; Subjects: Basketball players, Biography, Indiana Pacers (Basketball team), Accessible book, Protected DAISY; Places: United States; People: Reggie Miller, Reggie Miller (1965-)
To bring non-viewers up to speed: rich-girl Sun was gonna leave son-of-a-fisherman-turned-dad-in-laws-goon Jin, learning English from her rich (and bald) ex-boyfriend (well, hes not really...but this is just less complicated, trust me) in preparation for a dash to America. She got cold feet and they both ended up in the crash on the island. Jins got gender-role and class-insecurity issues a-plenty. After some rough patches, including attacking the black single-father (now his friend) for "stealing" his father-in-laws watch, being accused of setting a raft on fire, finding out his wife secretly knew English, setting off on the rebuilt raft and then getting captured by other survivors, Jins back with his wife, trying to work through all his macho controlling crap. Its resurfaced a bit though, with last nights freak-out over Sun being out in the jungle alone (she was recently the victim of a fake kidnapping, again, if you dont watch, never mind, its too complicated...) and the flash-back ...
The main results of the present study is that BKChs are tightly colocalized with voltage-gated Ca2+ channels such that Ca2+ ions have to diffuse, on average, only ∼13 nm after entering the cell before they bind to BKChs. The operation of BKChs by nanodomains of single Ca2+ channels provides several unique advantages, as discussed below. This functional colocalization was determined by a novel approach based on a linear approximation of buffered Ca2+ diffusion in microdomains (Neher, 1986; Stern, 1992; Naraghi, 1997).. This approach involved the quantitative analysis of the effect of the Ca2+ chelator BAPTA on the repolarization phase of action potentials, which we have shown to be potently shaped by BKChs. When we plotted the ln-transformed normalized local Ca2+ versus the inverse buffer length constant (1/λ), the points could be well fitted with a line through the origin and a slope of 12.7 nm. Because our approach involves a calibration of the Ca2+-dependent response (action potential ...
The water was freezing! Yes, I did fall in. But not because of the rapids. While we were navigating the river I surprisingly never felt like I would fall in. I was only in the water when I was either 1) pushed in by our guide ("Hey! You guys sit on the edge of the raft while I check the air pressure of the seats..." Splash!) or 2) when I was suckered into riding the bull. Oh, the bull. In a raft, "riding the bull" means that you sit on the front edge of the boat and let your legs hang over into the water. You are supposed to grab the rope (that goes around the perimeter of the raft) with one hand and wave your other arm around in the air. The guide said over and over "It is the safest seat in the raft. When we go through the rapids the front of the boat will pop up and if you fall, you will fall back into the boat." First of all, this is the same guide that just had us sit on the edge of the raft to "check the air pressure" while he pushed us into the water. Second, "when we go through the ...
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Talking to the Indianapolis Star about Reggie Miller, the former point guard had high praise for his Hall of Fame-bound Pacers teammate. Maybe he forgot that Jerry West, the man who IS the NBA logo and happens to work in the Warriors front office, played the two guard.

JoVE | Peer Reviewed Scientific Video Journal - Methods and ProtocolsJoVE | Peer Reviewed Scientific Video Journal - Methods and Protocols

Lipid rafts are membrane microdomains enriched in cholesterol and sphingolipids. They play a role in cellular physiological ... All cellular processes depend on the functionality of proteins. Although the functionality of a given protein is the direct ... Mitch explains how glycolipid agonists are being used as therapeutic agents to activate NKT cells in cancer patients and how ... In the past fifteen years the notion that cell membranes are not homogenous and rely on microdomains to exert their functions ...
more infohttps://www.jove.com/visualize/abstract/25140899/deciphering-glycolipid-code-alzheimer-s-parkinson-s-amyloid-proteins

JoVE | Peer Reviewed Scientific Video Journal - Methods and ProtocolsJoVE | Peer Reviewed Scientific Video Journal - Methods and Protocols

Mitochondria-associated ER Membranes (MAMs) and Glycosphingolipid Enriched Microdomains (GEMs): Isolation from Mouse Brain ... The ER serves as the primary store of intracellular Ca2+, and in this capacity regulates a myriad of cellular processes ... The intricate membrane system of the chloroplast contains unique glycerolipids, namely glycolipids lacking phosphorus: ... Neuroscience, Issue 73, Genetics, Cellular Biology, Molecular Biology, Biochemistry, Membrane Microdomains, Endoplasmic ...
more infohttps://www.jove.com/visualize/abstract/23894633/glycolipid-transfer-protein-expression-is-affected-glycosphingolipid

Lipid raft - WikipediaLipid raft - Wikipedia

These specialised membrane microdomains compartmentalise cellular processes by serving as organising centers for the assembly ... Netherlands refocused interest on these membrane microdomains, enriched with lipids and cholesterol, glycolipids, and ... Caveolae Cell membrane Cholesterol Lipid microdomain Membrane proteins Sphingomyelin Thomas, Sunil; Preda-Pais, Anca; Casares, ... and sphingolipid-enriched domains that compartmentalize cellular processes. Small rafts can sometimes be stabilized to form ...
more infohttps://en.wikipedia.org/wiki/Lipid_raft

Membrane Lipid Domains: Techniques for Visualization and Characterization | Bentham ScienceMembrane Lipid Domains: Techniques for Visualization and Characterization | Bentham Science

... and glycolipids. In cells, rafts further appear to be enriched in raft-targeted proteins. These observations have led to the ... application of spectroscopic and microscopic techniques to characterize attributes and dynamics of cellular lipid microdomains ... been provided implicating laterally organized lipid domains in a litany of both physiological and pathophysiological processes ... Abstract: Early studies in to lipids that comprised cellular membranes noted an asymmetrical distribution of lipids between ...
more infohttp://www.eurekaselect.com/58405/article/membrane-lipid-domains-techniques-visualization-and-characterization?tracking-code=4

Lipid Domain Structure of the Plasma Membrane Revealed by Patching of Membrane Components | JCBLipid Domain Structure of the Plasma Membrane Revealed by Patching of Membrane Components | JCB

Lateral assemblies of glycolipids and cholesterol, "rafts," have been implicated to play a role in cellular processes like ... interact with raft domains and cause formation of microdomains and indeed VSV envelopes have been shown to be somewhat enriched ... Bulk separation of membrane phases caused by clustering of membrane components. (A) Microdomains and membrane proteins in these ... If the monomeric membrane component has a preference for specific membrane microdomains multiple membrane interactions of the ...
more infohttp://jcb.rupress.org/content/141/4/929?ijkey=63ba8c3a0a3a42f25199a2b7fb9d1f75f7a8648e&keytype2=tf_ipsecsha

Cell membrane - WikipediaCell membrane - Wikipedia

Lipid rafts and caveolae are examples of cholesterol-enriched microdomains in the cell membrane.[21] Also, a fraction of the ... cell membranes are involved in a variety of cellular processes such as cell adhesion, ion conductivity and cell signalling and ... The cell membrane consists of three classes of amphipathic lipids: phospholipids, glycolipids, and sterols. The amount of each ... plasmatic membrane (Pfeffer, 1900),[13] plasma membrane, cytoplasmic membrane, cell envelope and cell membrane.[14][15] Some ...
more infohttps://en.wikipedia.org/wiki/Basolateral

Mediators of innate immune recognition of bacteria concentrate in lipid rafts and facilitate lipopolysaccharide-induced cell...Mediators of innate immune recognition of bacteria concentrate in lipid rafts and facilitate lipopolysaccharide-induced cell...

... lipid rafts are enriched in glycosphingolipids and cholesterol and have been implicated in cellular processes such as membrane ... The plasma membrane of cells is composed of lateral heterogeneities, patches and microdomains. These membrane microdomains or ... detergent-insoluble glycolipid-enriched complexes (DIGs) or glycosphingolipid-enriched membranes (GEMs) ( Horejsi et al., 1998 ... Brown, D. A. and Rose, J. K. ( 1992). Sorting of GPI-anchored proteins to glycolipid-enriched membrane subdomains during ...
more infohttp://jcs.biologists.org/content/115/12/2603

Cell membrane - WikipediaCell membrane - Wikipedia

Lipid rafts and caveolae are examples of cholesterol-enriched microdomains in the cell membrane.[21] Also, a fraction of the ... cell membranes are involved in a variety of cellular processes such as cell adhesion, ion conductivity and cell signalling and ... The cell membrane consists of three classes of amphipathic lipids: phospholipids, glycolipids, and sterols. The amount of each ... plasmatic membrane (Pfeffer, 1900),[13] plasma membrane, cytoplasmic membrane, cell envelope and cell membrane.[14][15] Some ...
more infohttps://en.m.wikipedia.org/wiki/Cytoplasmic_membrane

Cell membrane - WikipediaCell membrane - Wikipedia

Lipid rafts and caveolae are examples of cholesterol-enriched microdomains in the cell membrane.[22] Also, a fraction of the ... cell membranes are involved in a variety of cellular processes such as cell adhesion, ion conductivity and cell signalling and ... The cell membrane consists of three classes of amphipathic lipids: phospholipids, glycolipids, and sterols. The amount of each ... plasmatic membrane (Pfeffer, 1900),[14] plasma membrane, cytoplasmic membrane, cell envelope and cell membrane.[15][16] Some ...
more infohttps://en.m.wikipedia.org/wiki/Cell_membrane

Association of Influenza Virus Proteins with Membrane RaftsAssociation of Influenza Virus Proteins with Membrane Rafts

... enriched in glycerophospholipids and an "export domain" enriched in cholesterol and sphingolipids. Processing enzymes, such as ... A liquid membrane is required to allow the fusion of virus particles with cellular membranes. ... Thus, HA somehow accumulates in microdomains of the membrane or even induces their formation, which leads to its separation ... clusters with a glycolipid-anchored protein, an established marker for rafts of the outer leaflet. In this construct, tagging ...
more infohttps://www.hindawi.com/journals/av/2011/370606/

Statins Inhibit HIV-1 Infection by Down-regulating Rho Activity  | Journal of Experimental Medicine | Rockefeller University...Statins Inhibit HIV-1 Infection by Down-regulating Rho Activity | Journal of Experimental Medicine | Rockefeller University...

Evidence for budding of human immunodeficiency virus type 1 selectively from glycolipid-enriched membrane lipid rafts. J. Virol ... Membrane raft microdomains mediate lateral assemblies required for HIV-1 infection. EMBO Rep. ... Lov Effect on Ras Processing and Vesicle Fusion. Lysates from MT2-CCR5 cells treated with Lov, Lov plus cholesterol, Lov plus ... We show that at the cellular level, statins inhibit viral entry and budding by preventing Rho geranylgeranylation. Based on the ...
more infohttps://rupress.org/jem/article/200/4/541/46254/Statins-Inhibit-HIV-1-Infection-by-Down-regulating

Membrane microdomains and caveolae.  - PubMed - NCBIMembrane microdomains and caveolae. - PubMed - NCBI

... within the plasma membrane of eukaryotic cells have been implicated in many important cellular processes, such as polarized ... Glycosphingolipid- and cholesterol-enriched microdomains, or rafts, ... Membrane microdomains and caveolae.. Kurzchalia TV1, Parton RG.. Author information. 1. Max Planck Institute for Molecular Cell ... Glycolipids/metabolism*. *Humans. *Lymphocytes/metabolism. *Membrane Proteins/metabolism. *Muscular Dystrophies/metabolism. * ...
more infohttps://www.ncbi.nlm.nih.gov/pubmed/10449327?dopt=Abstract

Cell membrane - WikipediaCell membrane - Wikipedia

In addition, cell membranes are involved in a variety of cellular processes such as cell adhesion, ion conductivity and cell ... Lipid rafts and caveolae are examples of cholesterol-enriched microdomains in the cell membrane. Also, a fraction of the lipid ... The cell membrane consists of three classes of amphipathic lipids: phospholipids, glycolipids, and sterols. The amount of each ... plasmatic membrane (Pfeffer, 1900), plasma membrane, cytoplasmic membrane, cell envelope and cell membrane. Some authors that ...
more infohttps://en.wikipedia.org/wiki/Cell_membrane

Lipid Raft Proteins and Their Identification in T Lymphocytes | SpringerLinkLipid Raft Proteins and Their Identification in T Lymphocytes | SpringerLink

This review focuses on how membrane lipid rafts have been detected and isolated, mostly from lymphocytes, and their associated ... Rodgers, W, and Zavzavadjian, J. [ 2001 ]. Glycolipid-enriched membrane domains are assembled into membrane patches by ... Zhang, W, Trible, R.P., and Samelson, L.E. [ 1998 ]. LAT palmitoylation: its essential role in membrane microdomain targeting ... Fc epsilon RI-mediated recruitment of p53/56lyn to detergent-resistant membrane domains accompanies cellular signaling. Proc ...
more infohttps://link.springer.com/chapter/10.1007/978-1-4757-5806-1_3

Cell membrane - wikidocCell membrane - wikidoc

Lipid rafts and caveolae are examples of cholesterol-enriched microdomains in the cell membrane. ... which are involved in a vast array of cellular processes, and also serves as the attachment point for both the intracellular ... The cell membrane consists of three classes of amphipathic lipids: phospholipids, glycolipids, and steroids. The relative ... Integral membrane proteins. The cell membrane contains many integral membrane proteins which pepper the entire surface. These ...
more infohttp://wikidoc.org/index.php/Cell_membrane

Frontiers | Neuraminidase-3 Is a Negative Regulator of LFA-1 Adhesion | ChemistryFrontiers | Neuraminidase-3 Is a Negative Regulator of LFA-1 Adhesion | Chemistry

The enzyme is known to prefer glycolipid substrates, and we confirmed that exogenous enzyme altered the glycolipid composition ... Enzymatic activity of NEU3 resulted in re-organization of LFA-1 into large clusters on the membrane. This change was ... The enzyme is known to prefer glycolipid substrates, and we confirmed that exogenous enzyme altered the glycolipid composition ... Enzymatic activity of NEU3 resulted in re-organization of LFA-1 into large clusters on the membrane. This change was ...
more infohttps://www.frontiersin.org/articles/10.3389/fchem.2019.00791/full

Cell membraneCell membrane

... also called the plasma membrane, plasmalemma or phospholipid bilayer) is a semipermeable lipid bilayer found in all ... Lipid rafts and caveolae are examples of cholesterol-enriched microdomains in the cell membrane. ... which are involved in a vast array of cellular processes, and also serves as the attachment point for both the intracellular ... The cell membrane consists of three classes of amphipathic lipids: phospholipids, glycolipids, and steroids. The relative ...
more infohttps://www.bionity.com/en/encyclopedia/Cell_membrane.html

Cell membrane : Wikis (The Full Wiki)Cell membrane : Wikis (The Full Wiki)

Lipid rafts and caveolae are examples of cholesterol-enriched microdomains in the cell membrane. ... which are involved in a variety of cellular processes such as cell adhesion, ion channel conductance and cell signaling. The ... The cell membrane consists of three classes of amphipathic lipids: phospholipids, glycolipids, and steroids. The amount of each ... Membrane homeostasis, tension regulation, mechanosensitive membrane exchange and membrane traffic - Cell membrane homeostasis, ...
more infohttp://www.thefullwiki.org/Cell_membrane

Lateral diffusion of Toll-like receptors reveals that they are transiently confined within lipid rafts on the plasma membrane |...Lateral diffusion of Toll-like receptors reveals that they are transiently confined within lipid rafts on the plasma membrane |...

Brown, D. A. and Rose, J. K. (1992). Sorting of GPI-anchored proteins to glycolipid-enriched membrane subdomains during ... Membrane microdomains or `lipid rafts have been proposed as lateral structural components of the plasma membrane (Simons and ... 1A), whereas the rest of the cellular membrane was found in the lower fractions. Immunoblotting with a TLR2-specific mAb ... In those cells TLR molecules must be in the process of associating with lipid rafts but have not yet formed activation clusters ...
more infohttp://jcs.biologists.org/content/117/17/4007?ijkey=5510f0da1c1369aa0b71dc0891f149e3908469d4&keytype2=tf_ipsecsha

Cholesterol Supplementation During Production Increases the Infectivity of Retroviral and Lentiviral Vectors Pseudotyped with...Cholesterol Supplementation During Production Increases the Infectivity of Retroviral and Lentiviral Vectors Pseudotyped with...

Evidence for budding of human immunodeficiency virus type 1 selectively from glycolipid-enriched membrane lipid rafts. J Virol ... Cell membrane microdomains called lipid rafts are essential in the assembly of several enveloped viruses such as influenza, ... Depletion of cellular cholesterol inhibits membrane binding and higher-order multimerization of human immunodeficiency virus ... Please note that during the production process errors may be discovered which could affect the content, and all legal ...
more infohttp://pubmedcentralcanada.ca/pmcc/articles/PMC2663912/

Istituto Veneto di Scienze, Lettere ed Arti - LIstituto - Accademici - Giampietro SchiavoIstituto Veneto di Scienze, Lettere ed Arti - L'Istituto - Accademici - Giampietro Schiavo

TSPAN5 enriched microdomains provide a platform for dendritic spine maturation through neuroligin-1 clustering. Cell Rep, in ... Translocation of bacterial protein toxins across membranes. In "Biochemistry of cell membranes. A compendium of selected topics ... In "Cellular and molecular mechanisms of toxin action. Secretory systems and toxin". M Linial, A Grasso, P Lazarovici Eds, ... 2009) Analysis of lectin binding to glycolipid complexes using combinatorial microarrays. Glycobiology 19, 789-796.. 56. ...
more infohttp://www.istitutoveneto.it/flex/cm/pages/ServeBLOB.php/L/IT/IDPagina/1686

OCRL1 function in renal epithelial membrane traffic | Renal PhysiologyOCRL1 function in renal epithelial membrane traffic | Renal Physiology

Like HA, a fraction of megalin has been reported to reside in glycolipid-enriched microdomains, or lipid rafts (32), although ... and then fixed and processed for confocal microscopy. The total cellular population of mini-megalin was visualized using the ... This is consistent with the fact that most of the cellular PIP2 is present at the plasma membrane, whereas OCRL1 is largely ... OCRL1 function in renal epithelial membrane traffic. Shanshan Cui, Christopher J. Guerriero, Christina M. Szalinski, Carol L. ...
more infohttp://ajprenal.physiology.org/content/298/2/F335

Trends in Glycoscience and GlycotechnologyTrends in Glycoscience and Glycotechnology

... and cholesterol-enriched microdomains, or lipid rafts, within the plasma membrane of eukaryotic cells are implicated in many ... as well as by some glycolipids. Numerous recent data suggest that the signaling capacity of the aggregated membrane ... important cellular events, such as polarized sorting of apical membrane proteins in epithelial cells and signal transduction. ... the binding of Stx to Gb3 might cause temporal activation of Yes in DS in the process of apoptosis. ...
more infohttps://www.jstage.jst.go.jp/browse/tigg/13/71/_contents/-char/en

Frontiers | The Cellular Prion Protein: A Player in Immunological Quiescence | ImmunologyFrontiers | The Cellular Prion Protein: A Player in Immunological Quiescence | Immunology

... the physiological role of the cellular prion protein (PrPC) remains elusive. Here, we present a novel concept suggesting that ... the physiological role of the cellular prion protein (PrPC) remains elusive. Here, we present a novel concept suggesting that ... in lymphoid cells PrPC has been shown to be recruited into microdomains of the membrane, the so-called immunological synapses ... Harris DA, Huber MT, van Dijken P, Shyng SL, Chait BT, Wang R. Processing of a cellular prion protein: identification of N- and ...
more infohttps://www.frontiersin.org/articles/10.3389/fimmu.2015.00450/full

Diet and Cholesterol sub-cluster 28Diet and Cholesterol sub-cluster 28

Lipid rafts are membrane microdomains enriched in cholesterol, sphingolipids, and glycolipids that have been implicated in many ... is an essential constituent of all mammalian cell membranes and its availability is therefore a prerequisite for cellular ... biological processes. Since cholesterol is known to play a key role in the entry of some other viruses, we investigated the ... Although lipid-rich microdomains of hepatocyte plasma membranes serve as the major scaffolding regions for cholesterol ...
more infohttp://www.biomedsearch.com/cluster/23/Diet-and-Cholesterol/sub-28.html
  • In 1890, an update to the Cell Theory stated that cell membranes existed, but were merely secondary structures. (wikipedia.org)
  • These structures, which can be visualized by electron microscopy or fluorescence microscopy , can be found on the inside of the membrane, the outside, or through-and-through . (wikidoc.org)
  • In addition, the driving force in which glycolipids form cluster structures has been examined by analysis of the surface pressure-molecular area isotherm of an air-water interface monolayer, and by observation of the topology of mixed lipid membranes by atomic force microscope. (go.jp)
  • Using biochemical as well as fluorescence imaging techniques, TLR2 and TLR4 were found to be recruited within microdomains upon stimulation by bacterial products. (biologists.org)
  • Though it is important to clarify the effect of raft formation on the biochemical function, it is also necessary to study the physiochemical factor in the formation of glycolipid domain. (go.jp)
  • The ECM provides essential physical scaffolding for the cellular constituents, as well as contributes to crucial biochemical signaling. (biomedcentral.com)
  • The download is also to the transcription involved at the mitochondrial font of the mouse, where it not is biochemical apoptosis microdomains. (evakoch.com)
  • In eukaryotes, sterols are crucial for modulating the molecular order of membranes. (pnas.org)
  • The aim of the 3rd group is to investigate the molecular mechanisms of the diseases derived from the glycosylation disorders with focus on the roles of membrane microdomains. (jcgg.jp)
  • This review aims at describing the molecular events occurring during MA-membrane interaction, and pointing out their consequences in terms of viral assembly. (biomedcentral.com)
  • Many data have been recently published partially unveiling the molecular mechanism of MA lipid binding, enhancing the understanding of the role played by MA during Gag membrane targeting and assembly. (biomedcentral.com)
  • Although significant progress has been made in the understanding of cancer at the molecular and cellular level, the potency of chemotherapy of advanced malignant tumors is still limited and based on conventional cytotoxic drugs calling for medications with new mechanism of action [ 1 ]. (mdpi.com)
  • His research interests range from molecular and cellular biology to clinical investigations. (oncotarget.com)
  • A lipidome comparison of the plasma membrane of fresh semen from carriers and controls showed significant differences in the concentration of phosphatidylcholine (PC), diacylglycerol (DAG), ceramide (Cer), sphingomyelin (SM), and phosphatidylcholine (-ether) (PC O-), indicating that ABHD16B plays a role in lipid biosynthesis. (lipotype.com)
  • Correspondingly, the peptide had a particular affinity for raft-like membranes containing both GM1 and cholesterol. (jove.com)
  • Experimental evidence largely based upon detergent isolation of raft domains has since been provided implicating laterally organized lipid domains in a litany of both physiological and pathophysiological processes including T-cell activation, B-cell antigen signaling, thromboregulation, Alzheimers disease and atherosclerosis. (eurekaselect.com)
  • This review seeks to summarize the current knowledge and understanding of raft structure, and provide a first foray in to the fundamentals and application of spectroscopic and microscopic techniques to characterize attributes and dynamics of cellular lipid microdomains. (eurekaselect.com)
  • Lipid raft integrity is essential for LPS-cellular activation, since raft-disrupting drugs, such as nystatin or MCD, inhibit LPS-induced TNF-α secretion. (biologists.org)
  • Although the importance of lipid raft formation for the acquired immune recognition is clear, the involvement of membrane microdomains in the innate immune response has not yet been investigated. (biologists.org)
  • Lipid raft microdomain compartmentalization of TC10 is required for insulin signaling and GLUT4 translocation. (edu.au)
  • Many cell types have been reported to secrete small vesicles called exosomes, that are derived from multivesicular bodies and that can also form from endocytic-like lipid raft domains of the plasma membrane. (biomedcentral.com)
  • In one specific scenario, exosomes are proposed to bud from the lipid raft region of the postsynaptic membrane adjacent to the postsynaptic density, in a manner that is stimulated by stimuli that elicit long-term potentiation. (biomedcentral.com)
  • OCRL1 is localized primarily at the trans -Golgi network (TGN) and is also associated with a subset of endosomes and with clathrin-coated pits, suggesting a potential function of this enzyme in membrane traffic through these compartments ( 8 , 9 , 15 , 16 , 46 ). (physiology.org)
  • In the absence of insulin, Glut4 slowly recycles between the plasma membrane and vesicular compartments within the cell, where most of the Glut4 resides. (beds.ac.uk)
  • The cellular compartments that harbor Aβ are target sites for therapeutic intervention. (nature.com)
  • A major difference between eukayotes and prokaryotes is the presence of physical compartments (membrane bound) within the cell. (edu.au)
  • These compartments allow the separation/specialization of processes within the cell. (edu.au)
  • There also exist within each of these physical compartments, functional compartments where specific processes may occur or are restricted too. (edu.au)
  • This lecture is an introduction to compartments within the cell and membranes. (edu.au)
  • Sialic acid-containing glycolipids, known as gangliosides, play important structural and functional roles. (frontiersin.org)
  • The structural role of cholesterol is particularly relevant in the central nervous system, where it represents one of the major components of myelin sheaths, and an important constituent of the synaptic vesicle membranes. (annexpublishers.co)
  • In this review, we focus on the importance of plasma membrane domain structural and signaling functionalities as well as how loss of membrane homeostasis can drive aberrant signaling. (deepdyve.com)
  • The formation of higher order Gag multimers leads to the formation of the viral particle at the plasma membrane, and subsequent budding and maturation, which consist of the proteolytic cleavage of Gag and structural rearrangement of the particle. (biomedcentral.com)
  • Many refuted the existence of a cell membrane still towards the end of the 19th century. (wikipedia.org)
  • In addition, FRAP also provided us with the extent of fluorescence recovery, which indicates the percentage of molecules that are moving into the area, and also the existence of membrane microdomains. (biologists.org)
  • Olive, S., Dubois, C., Schachner, M. & Rougon, G. The F3 neuronal glycosylphosphatidylinositol-linked molecule is localized ot glycolipid-enriched membrane sub-domains and interacts with L1 and Fyn kinase in cerebellum. (nature.com)
  • Given the known stimulatory roles of PIP 2 in these processes, it is not immediately obvious how loss of OCRL1 function might lead to Fanconi syndrome in Lowe syndrome patients. (physiology.org)
  • repeats are the other pathway for most roles except HDAC6 which is surprisingly clear and processes on alpha-tublin( Hubbert et al. (evakoch.com)
  • In addition, membranes in prokaryotes and in the mitochondria and chloroplasts of eukaryotes facilitate the synthesis of ATP through chemiosmosis. (wikidoc.org)
  • Furthermore, multidrug transport is impaired in a hopanoid-deficient mutant of the gram-negative Methylobacterium extorquens , which introduces a link between membrane order and an energy-dependent, membrane-associated function in prokaryotes. (pnas.org)
  • Just as material can be brought into the cell by invagination and formation of a vesicle, the membrane of a vesicle can be fused with the plasma membrane, extruding its contents to the surrounding medium. (ipfs.io)