Serine: A non-essential amino acid occurring in natural form as the L-isomer. It is synthesized from GLYCINE or THREONINE. It is involved in the biosynthesis of PURINES; PYRIMIDINES; and other amino acids.Phosphorylation: The introduction of a phosphoryl group into a compound through the formation of an ester bond between the compound and a phosphorus moiety.Tyrosine: A non-essential amino acid. In animals it is synthesized from PHENYLALANINE. It is also the precursor of EPINEPHRINE; THYROID HORMONES; and melanin.Protein-Serine-Threonine Kinases: A group of enzymes that catalyzes the phosphorylation of serine or threonine residues in proteins, with ATP or other nucleotides as phosphate donors.PhosphoproteinsProtein Kinases: A family of enzymes that catalyze the conversion of ATP and a protein to ADP and a phosphoprotein.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.Oxidative Phosphorylation: Electron transfer through the cytochrome system liberating free energy which is transformed into high-energy phosphate bonds.Phosphoserine: The phosphoric acid ester of serine.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 Line: Established cell cultures that have the potential to propagate indefinitely.Threonine: An essential amino acid occurring naturally in the L-form, which is the active form. It is found in eggs, milk, gelatin, and other 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.Protein-Tyrosine Kinases: Protein kinases that catalyze the PHOSPHORYLATION of TYROSINE residues in proteins with ATP or other nucleotides as phosphate donors.Protein Kinase C: An serine-threonine protein kinase that requires the presence of physiological concentrations of CALCIUM and membrane PHOSPHOLIPIDS. The additional presence of DIACYLGLYCEROLS markedly increases its sensitivity to both calcium and phospholipids. The sensitivity of the enzyme can also be increased by PHORBOL ESTERS and it is believed that protein kinase C is the receptor protein of tumor-promoting phorbol esters.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.Cyclic AMP-Dependent Protein Kinases: A group of enzymes that are dependent on CYCLIC AMP and catalyze the phosphorylation of SERINE or THREONINE residues on proteins. Included under this category are two cyclic-AMP-dependent protein kinase subtypes, each of which is defined by its subunit composition.PhosphopeptidesPhosphotyrosine: An amino acid that occurs in endogenous proteins. Tyrosine phosphorylation and dephosphorylation plays a role in cellular signal transduction and possibly in cell growth control and carcinogenesis.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.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.Proto-Oncogene Proteins c-akt: A protein-serine-threonine kinase that is activated by PHOSPHORYLATION in response to GROWTH FACTORS or INSULIN. It plays a major role in cell metabolism, growth, and survival as a core component of SIGNAL TRANSDUCTION. Three isoforms have been described in mammalian cells.Mitogen-Activated Protein Kinases: A superfamily of PROTEIN-SERINE-THREONINE KINASES that are activated by diverse stimuli via protein kinase cascades. They are the final components of the cascades, activated by phosphorylation by MITOGEN-ACTIVATED PROTEIN KINASE KINASES, which in turn are activated by mitogen-activated protein kinase kinase kinases (MAP KINASE KINASE KINASES).Phosphothreonine: The phosphoric acid ester of threonine. Used as an identifier in the analysis of peptides, proteins, and enzymes.Kinetics: The rate dynamics in chemical or physical systems.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.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.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.Peptide Mapping: Analysis of PEPTIDES that are generated from the digestion or fragmentation of a protein or mixture of PROTEINS, by ELECTROPHORESIS; CHROMATOGRAPHY; or MASS SPECTROMETRY. The resulting peptide fingerprints are analyzed for a variety of purposes including the identification of the proteins in a sample, GENETIC POLYMORPHISMS, patterns of gene expression, and patterns diagnostic for diseases.Casein Kinase II: A ubiquitous casein kinase that is comprised of two distinct catalytic subunits and dimeric regulatory subunit. Casein kinase II has been shown to phosphorylate a large number of substrates, many of which are proteins involved in the regulation of gene expression.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.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.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.Phosphoprotein Phosphatases: A group of enzymes removing the SERINE- or THREONINE-bound phosphate groups from a wide range of phosphoproteins, including a number of enzymes which have been phosphorylated under the action of a kinase. (Enzyme Nomenclature, 1992)Proto-Oncogene Proteins: Products of proto-oncogenes. Normally they do not have oncogenic or transforming properties, but are involved in the regulation or differentiation of cell growth. They often have protein kinase activity.Binding Sites: The parts of a macromolecule that directly participate in its specific combination with another molecule.Mitogen-Activated Protein Kinase 1: A proline-directed serine/threonine protein kinase which mediates signal transduction from the cell surface to the nucleus. Activation of the enzyme by phosphorylation leads to its translocation into the nucleus where it acts upon specific transcription factors. p40 MAPK and p41 MAPK are isoforms.Intracellular Signaling Peptides and Proteins: Proteins and peptides that are involved in SIGNAL TRANSDUCTION within the cell. Included here are peptides and proteins that regulate the activity of TRANSCRIPTION FACTORS and cellular processes in response to signals from CELL SURFACE RECEPTORS. Intracellular signaling peptide and proteins may be part of an enzymatic signaling cascade or act through binding to and modifying the action of other signaling factors.Calcium-Calmodulin-Dependent Protein Kinases: A CALMODULIN-dependent enzyme that catalyzes the phosphorylation of proteins. This enzyme is also sometimes dependent on CALCIUM. A wide range of proteins can act as acceptor, including VIMENTIN; SYNAPSINS; GLYCOGEN SYNTHASE; MYOSIN LIGHT CHAINS; and the MICROTUBULE-ASSOCIATED PROTEINS. (From Enzyme Nomenclature, 1992, p277)Phosphatidylinositol 3-Kinases: Phosphotransferases that catalyzes the conversion of 1-phosphatidylinositol to 1-phosphatidylinositol 3-phosphate. Many members of this enzyme class are involved in RECEPTOR MEDIATED SIGNAL TRANSDUCTION and regulation of vesicular transport with the cell. Phosphatidylinositol 3-Kinases have been classified both according to their substrate specificity and their mode of action within the cell.Glycogen Synthase Kinase 3: A glycogen synthase kinase that was originally described as a key enzyme involved in glycogen metabolism. It regulates a diverse array of functions such as CELL DIVISION, microtubule function and APOPTOSIS.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.Recombinant Proteins: Proteins prepared by recombinant DNA technology.Mitogen-Activated Protein Kinase 3: A 44-kDa extracellular signal-regulated MAP kinase that may play a role the initiation and regulation of MEIOSIS; MITOSIS; and postmitotic functions in differentiated cells. It phosphorylates a number of TRANSCRIPTION FACTORS; and MICROTUBULE-ASSOCIATED PROTEINS.Cell Line, Tumor: A cell line derived from cultured tumor cells.Extracellular Signal-Regulated MAP Kinases: A mitogen-activated protein kinase subfamily that is widely expressed and plays a role in regulation of MEIOSIS; MITOSIS; and post mitotic functions in differentiated cells. The extracellular signal regulated MAP kinases are regulated by a broad variety of CELL SURFACE RECEPTORS and can be activated by certain CARCINOGENS.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.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.Mutagenesis, Site-Directed: Genetically engineered MUTAGENESIS at a specific site in the DNA molecule that introduces a base substitution, or an insertion or deletion.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.MAP Kinase Signaling System: An intracellular signaling system involving the MAP kinase cascades (three-membered protein kinase cascades). Various upstream activators, which act in response to extracellular stimuli, trigger the cascades by activating the first member of a cascade, MAP KINASE KINASE KINASES; (MAPKKKs). Activated MAPKKKs phosphorylate MITOGEN-ACTIVATED PROTEIN KINASE KINASES which in turn phosphorylate the MITOGEN-ACTIVATED PROTEIN KINASES; (MAPKs). The MAPKs then act on various downstream targets to affect gene expression. In mammals, there are several distinct MAP kinase pathways including the ERK (extracellular signal-regulated kinase) pathway, the SAPK/JNK (stress-activated protein kinase/c-jun kinase) pathway, and the p38 kinase pathway. There is some sharing of components among the pathways depending on which stimulus originates activation of the cascade.DNA-Binding Proteins: Proteins which bind to DNA. The family includes proteins which bind to both double- and single-stranded DNA and also includes specific DNA binding proteins in serum which can be used as markers for malignant diseases.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.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.Adaptor Proteins, Signal Transducing: A broad category of carrier proteins that play a role in SIGNAL TRANSDUCTION. They generally contain several modular domains, each of which having its own binding activity, and act by forming complexes with other intracellular-signaling molecules. Signal-transducing adaptor proteins lack enzyme activity, however their activity can be modulated by other signal-transducing enzymesCOS 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).)p38 Mitogen-Activated Protein Kinases: A mitogen-activated protein kinase subfamily that regulates a variety of cellular processes including CELL GROWTH PROCESSES; CELL DIFFERENTIATION; APOPTOSIS; and cellular responses to INFLAMMATION. The P38 MAP kinases are regulated by CYTOKINE RECEPTORS and can be activated in response to bacterial pathogens.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.Cell Cycle Proteins: Proteins that control the CELL DIVISION CYCLE. This family of proteins includes a wide variety of classes, including CYCLIN-DEPENDENT KINASES, mitogen-activated kinases, CYCLINS, and PHOSPHOPROTEIN PHOSPHATASES as well as their putative substrates such as chromatin-associated proteins, CYTOSKELETAL PROTEINS, and TRANSCRIPTION FACTORS.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.Electrophoresis, Polyacrylamide Gel: Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.Myosin Light Chains: The smaller subunits of MYOSINS that bind near the head groups of MYOSIN HEAVY CHAINS. The myosin light chains have a molecular weight of about 20 KDa and there are usually one essential and one regulatory pair of light chains associated with each heavy chain. Many myosin light chains that bind calcium are considered "calmodulin-like" proteins.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.Tetradecanoylphorbol Acetate: A phorbol ester found in CROTON OIL with very effective tumor promoting activity. It stimulates the synthesis of both DNA and RNA.Okadaic Acid: A specific inhibitor of phosphoserine/threonine protein phosphatase 1 and 2a. It is also a potent tumor promoter. (Thromb Res 1992;67(4):345-54 & Cancer Res 1993;53(2):239-41)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.CDC2 Protein Kinase: Phosphoprotein with protein kinase activity that functions in the G2/M phase transition of the CELL CYCLE. It is the catalytic subunit of the MATURATION-PROMOTING FACTOR and complexes with both CYCLIN A and CYCLIN B in mammalian cells. The maximal activity of cyclin-dependent kinase 1 is achieved when it is fully dephosphorylated.Substrate Specificity: A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.Cyclic AMP: An adenine nucleotide containing one phosphate group which is esterified to both the 3'- and 5'-positions of the sugar moiety. It is a second messenger and a key intracellular regulator, functioning as a mediator of activity for a number of hormones, including epinephrine, glucagon, and ACTH.Carrier Proteins: Transport proteins that carry specific substances in the blood or across cell membranes.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.Protein Kinase Inhibitors: Agents that inhibit PROTEIN KINASES.Cell Nucleus: Within a eukaryotic cell, a membrane-limited body which contains chromosomes and one or more nucleoli (CELL NUCLEOLUS). The nuclear membrane consists of a double unit-type membrane which is perforated by a number of pores; the outermost membrane is continuous with the ENDOPLASMIC RETICULUM. A cell may contain more than one nucleus. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)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.Antibodies, Phospho-Specific: Antibodies directed against immunogen-coupled phosphorylated PEPTIDES corresponding to amino acids surrounding the PHOSPHORYLATION site. They are used to study proteins involved in SIGNAL TRANSDUCTION pathways. (From Methods Mol Biol 2000; 99:177-89)Time Factors: Elements of limited time intervals, contributing to particular results or situations.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.Protein Tyrosine Phosphatases: An enzyme group that specifically dephosphorylates phosphotyrosyl residues in selected proteins. Together with PROTEIN-TYROSINE KINASE, it regulates tyrosine phosphorylation and dephosphorylation in cellular signal transduction and may play a role in cell growth control and carcinogenesis.Focal Adhesion Protein-Tyrosine Kinases: A family of non-receptor, PROLINE-rich protein-tyrosine kinases.Ribosomal Protein S6 Kinases, 90-kDa: A family of ribosomal protein S6 kinases that are structurally distinguished from RIBOSOMAL PROTEIN S6 KINASES, 70-KDA by their apparent molecular size and the fact they contain two functional kinase domains. Although considered RIBOSOMAL PROTEIN S6 KINASES, members of this family are activated via the MAP KINASE SIGNALING SYSTEM and have been shown to act on a diverse array of substrates that are involved in cellular regulation such as RIBOSOMAL PROTEIN S6 and CAMP RESPONSE ELEMENT-BINDING PROTEIN.3T3 Cells: Cell lines whose original growing procedure consisted being transferred (T) every 3 days and plated at 300,000 cells per plate (J Cell Biol 17:299-313, 1963). Lines have been developed using several different strains of mice. Tissues are usually fibroblasts derived from mouse embryos but other types and sources have been developed as well. The 3T3 lines are valuable in vitro host systems for oncogenic virus transformation studies, since 3T3 cells possess a high sensitivity to CONTACT INHIBITION.14-3-3 Proteins: A large family of signal-transducing adaptor proteins present in wide variety of eukaryotes. They are PHOSPHOSERINE and PHOSPHOTHREONINE binding proteins involved in important cellular processes including SIGNAL TRANSDUCTION; CELL CYCLE control; APOPTOSIS; and cellular stress responses. 14-3-3 proteins function by interacting with other signal-transducing proteins and effecting changes in their enzymatic activity and subcellular localization. The name 14-3-3 derives from numerical designations used in the original fractionation patterns of the proteins.Transcription Factors: Endogenous substances, usually proteins, which are effective in the initiation, stimulation, or termination of the genetic transcription process.Isoenzymes: Structurally related forms of an enzyme. Each isoenzyme has the same mechanism and classification, but differs in its chemical, physical, or immunological characteristics.Phosphorus Radioisotopes: Unstable isotopes of phosphorus that decay or disintegrate emitting radiation. P atoms with atomic weights 28-34 except 31 are radioactive phosphorus isotopes.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.Nuclear Proteins: Proteins found in the nucleus of a cell. Do not confuse with NUCLEOPROTEINS which are proteins conjugated with nucleic acids, that are not necessarily present in the nucleus.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.Cell Cycle: The complex series of phenomena, occurring between the end of one CELL DIVISION and the end of the next, by which cellular material is duplicated and then divided between two daughter cells. The cell cycle includes INTERPHASE, which includes G0 PHASE; G1 PHASE; S PHASE; and G2 PHASE, and CELL DIVISION PHASE.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.Paxillin: Paxillin is a signal transducing adaptor protein that localizes to FOCAL ADHESIONS via its four LIM domains. It undergoes PHOSPHORYLATION in response to integrin-mediated CELL ADHESION, and interacts with a variety of proteins including VINCULIN; FOCAL ADHESION KINASE; PROTO-ONCOGENE PROTEIN PP60(C-SRC); and PROTO-ONCOGENE PROTEIN C-CRK.Vanadates: Oxyvanadium ions in various states of oxidation. They act primarily as ion transport inhibitors due to their inhibition of Na(+)-, K(+)-, and Ca(+)-ATPase transport systems. They also have insulin-like action, positive inotropic action on cardiac ventricular muscle, and other metabolic effects.Protein Phosphatase 2: A phosphoprotein phosphatase subtype that is comprised of a catalytic subunit and two different regulatory subunits. At least two genes encode isoforms of the protein phosphatase catalytic subunit, while several isoforms of regulatory subunits exist due to the presence of multiple genes and the alternative splicing of their mRNAs. Protein phosphatase 2 acts on a broad variety of cellular proteins and may play a role as a regulator of intracellular signaling processes.Focal Adhesion Kinase 1: A non-receptor protein tyrosine kinase that is localized to FOCAL ADHESIONS and is a central component of integrin-mediated SIGNAL TRANSDUCTION PATHWAYS. Focal adhesion kinase 1 interacts with PAXILLIN and undergoes PHOSPHORYLATION in response to adhesion of cell surface integrins to the EXTRACELLULAR MATRIX. Phosphorylated p125FAK protein binds to a variety of SH2 DOMAIN and SH3 DOMAIN containing proteins and helps regulate CELL ADHESION and CELL MIGRATION.Insulin: A 51-amino acid pancreatic hormone that plays a major role in the regulation of glucose metabolism, directly by suppressing endogenous glucose production (GLYCOGENOLYSIS; GLUCONEOGENESIS) and indirectly by suppressing GLUCAGON secretion and LIPOLYSIS. Native insulin is a globular protein comprised of a zinc-coordinated hexamer. Each insulin monomer containing two chains, A (21 residues) and B (30 residues), linked by two disulfide bonds. Insulin is used as a drug to control insulin-dependent diabetes mellitus (DIABETES MELLITUS, TYPE 1).Protein Phosphatase 1: A eukayrotic protein serine-threonine phosphatase subtype that dephosphorylates a wide variety of cellular proteins. The enzyme is comprised of a catalytic subunit and regulatory subunit. Several isoforms of the protein phosphatase catalytic subunit exist due to the presence of multiple genes and the alternative splicing of their mRNAs. A large number of proteins have been shown to act as regulatory subunits for this enzyme. Many of the regulatory subunits have additional cellular functions.Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.Rats, Sprague-Dawley: A strain of albino rat used widely for experimental purposes because of its calmness and ease of handling. It was developed by the Sprague-Dawley Animal Company.Trans-Activators: Diffusible gene products that act on homologous or heterologous molecules of viral or cellular DNA to regulate the expression of proteins.Amino Acid Substitution: The naturally occurring or experimentally induced replacement of one or more AMINO ACIDS in a protein with another. If a functionally equivalent amino acid is substituted, the protein may retain wild-type activity. Substitution may also diminish, enhance, or eliminate protein function. Experimentally induced substitution is often used to study enzyme activities and binding site properties.Cell Membrane: The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.Molecular Weight: The sum of the weight of all the atoms in a molecule.Mitosis: A type of CELL NUCLEUS division by means of which the two daughter nuclei normally receive identical complements of the number of CHROMOSOMES of the somatic cells of the species.Mitogen-Activated Protein Kinase Kinases: A serine-threonine protein kinase family whose members are components in protein kinase cascades activated by diverse stimuli. These MAPK kinases phosphorylate MITOGEN-ACTIVATED PROTEIN KINASES and are themselves phosphorylated by MAP KINASE KINASE KINASES. JNK kinases (also known as SAPK kinases) are a subfamily.Dose-Response Relationship, Drug: The relationship between the dose of an administered drug and the response of the organism to the drug.HEK293 Cells: A cell line generated from human embryonic kidney cells that were transformed with human adenovirus type 5.Casein Kinases: A group of protein-serine-threonine kinases that was originally identified as being responsible for the PHOSPHORYLATION of CASEINS. They are ubiquitous enzymes that have a preference for acidic proteins. Casein kinases play a role in SIGNAL TRANSDUCTION by phosphorylating a variety of regulatory cytoplasmic and regulatory nuclear proteins.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.Fibroblasts: Connective tissue cells which secrete an extracellular matrix rich in collagen and other macromolecules.Epidermal Growth Factor: A 6-kDa polypeptide growth factor initially discovered in mouse submaxillary glands. Human epidermal growth factor was originally isolated from urine based on its ability to inhibit gastric secretion and called urogastrone. Epidermal growth factor exerts a wide variety of biological effects including the promotion of proliferation and differentiation of mesenchymal and EPITHELIAL CELLS. It is synthesized as a transmembrane protein which can be cleaved to release a soluble active form.Ribosomal Protein S6 Kinases: A family of protein serine/threonine kinases which act as intracellular signalling intermediates. Ribosomal protein S6 kinases are activated through phosphorylation in response to a variety of HORMONES and INTERCELLULAR SIGNALING PEPTIDES AND PROTEINS. Phosphorylation of RIBOSOMAL PROTEIN S6 by enzymes in this class results in increased expression of 5' top MRNAs. Although specific for RIBOSOMAL PROTEIN S6 members of this class of kinases can act on a number of substrates within the cell. The immunosuppressant SIROLIMUS inhibits the activation of ribosomal protein S6 kinases.Phosphates: Inorganic salts of phosphoric acid.Insulin Receptor Substrate Proteins: A structurally-related group of signaling proteins that are phosphorylated by the INSULIN RECEPTOR PROTEIN-TYROSINE KINASE. The proteins share in common an N-terminal PHOSPHOLIPID-binding domain, a phosphotyrosine-binding domain that interacts with the phosphorylated INSULIN RECEPTOR, and a C-terminal TYROSINE-rich domain. Upon tyrosine phosphorylation insulin receptor substrate proteins interact with specific SH2 DOMAIN-containing proteins that are involved in insulin receptor signaling.Peptide Fragments: Partial proteins formed by partial hydrolysis of complete proteins or generated through PROTEIN ENGINEERING techniques.Cyclin-Dependent Kinases: Protein kinases that control cell cycle progression in all eukaryotes and require physical association with CYCLINS to achieve full enzymatic activity. Cyclin-dependent kinases are regulated by phosphorylation and dephosphorylation events.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.Transcription, Genetic: The biosynthesis of RNA carried out on a template of DNA. The biosynthesis of DNA from an RNA template is called REVERSE TRANSCRIPTION.JNK Mitogen-Activated Protein Kinases: A subgroup of mitogen-activated protein kinases that activate TRANSCRIPTION FACTOR AP-1 via the phosphorylation of C-JUN PROTEINS. They are components of intracellular signaling pathways that regulate CELL PROLIFERATION; APOPTOSIS; and CELL DIFFERENTIATION.TOR Serine-Threonine Kinases: A serine threonine kinase that controls a wide range of growth-related cellular processes. The protein is referred to as the target of RAPAMYCIN due to the discovery that SIROLIMUS (commonly known as rapamycin) forms an inhibitory complex with TACROLIMUS BINDING PROTEIN 1A that blocks the action of its enzymatic activity.Ribosomal Protein S6: A ribosomal protein that may play a role in controlling cell growth and proliferation. It is a major substrate of RIBOSOMAL PROTEIN S6 KINASES and plays a role in regulating the translation (TRANSLATION, GENETIC) of RNAs that contain an RNA 5' TERMINAL OLIGOPYRIMIDINE SEQUENCE.Cricetinae: A subfamily in the family MURIDAE, comprising the hamsters. Four of the more common genera are Cricetus, CRICETULUS; MESOCRICETUS; and PHODOPUS.Cell Proliferation: All of the processes involved in increasing CELL NUMBER including CELL DIVISION.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.Cytoskeletal Proteins: Major constituent of the cytoskeleton found in the cytoplasm of eukaryotic cells. They form a flexible framework for the cell, provide attachment points for organelles and formed bodies, and make communication between parts of the cell possible.STAT3 Transcription Factor: A signal transducer and activator of transcription that mediates cellular responses to INTERLEUKIN-6 family members. STAT3 is constitutively activated in a variety of TUMORS and is a major downstream transducer for the CYTOKINE RECEPTOR GP130.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)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.Phosphotransferases: A rather large group of enzymes comprising not only those transferring phosphate but also diphosphate, nucleotidyl residues, and others. These have also been subdivided according to the acceptor group. (From Enzyme Nomenclature, 1992) EC 2.7.Cyclin-Dependent Kinase 5: A serine-threonine kinase that plays important roles in CELL DIFFERENTIATION; CELL MIGRATION; and CELL DEATH of NERVE CELLS. It is closely related to other CYCLIN-DEPENDENT KINASES but does not seem to participate in CELL CYCLE regulation.Casein Kinase I: A casein kinase that was originally described as a monomeric enzyme with a molecular weight of 30-40 kDa. Several ISOENZYMES of casein kinase I have been found which are encoded by separate genes. Many of the casein kinase I isoenzymes have been shown to play distinctive roles in intracellular SIGNAL TRANSDUCTION.src Homology Domains: Regions of AMINO ACID SEQUENCE similarity in the SRC-FAMILY TYROSINE KINASES that fold into specific functional tertiary structures. The SH1 domain is a CATALYTIC DOMAIN. SH2 and SH3 domains are protein interaction domains. SH2 usually binds PHOSPHOTYROSINE-containing proteins and SH3 interacts with CYTOSKELETAL PROTEINS.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.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.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.Proto-Oncogene Proteins pp60(c-src): Membrane-associated tyrosine-specific kinases encoded by the c-src genes. They have an important role in cellular growth control. Truncation of carboxy-terminal residues in pp60(c-src) leads to PP60(V-SRC) which has the ability to transform cells. This kinase pp60 c-src should not be confused with csk, also known as c-src kinase.Cell Division: The fission of a CELL. It includes CYTOKINESIS, when the CYTOPLASM of a cell is divided, and CELL NUCLEUS DIVISION.Mass Spectrometry: An analytical method used in determining the identity of a chemical based on its mass using mass analyzers/mass spectrometers.Receptor, Epidermal Growth Factor: A cell surface receptor involved in regulation of cell growth and differentiation. It is specific for EPIDERMAL GROWTH FACTOR and EGF-related peptides including TRANSFORMING GROWTH FACTOR ALPHA; AMPHIREGULIN; and HEPARIN-BINDING EGF-LIKE GROWTH FACTOR. The binding of ligand to the receptor causes activation of its intrinsic tyrosine kinase activity and rapid internalization of the receptor-ligand complex into the cell.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.Flavonoids: A group of phenyl benzopyrans named for having structures like FLAVONES.Histones: Small chromosomal proteins (approx 12-20 kD) possessing an open, unfolded structure and attached to the DNA in cell nuclei by ionic linkages. Classification into the various types (designated histone I, histone II, etc.) is based on the relative amounts of arginine and lysine in each.Phosphoric Monoester Hydrolases: A group of hydrolases which catalyze the hydrolysis of monophosphoric esters with the production of one mole of orthophosphate. EC 3.1.3.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.Androstadienes: Derivatives of the steroid androstane having two double bonds at any site in any of the rings.Eukaryotic Initiation Factor-2: Eukaryotic initiation factor of protein synthesis. In higher eukaryotes the factor consists of three subunits: alpha, beta, and gamma. As initiation proceeds, eIF-2 forms a ternary complex with Met-tRNAi and GTP.AMP-Activated Protein Kinases: Intracellular signaling protein kinases that play a signaling role in the regulation of cellular energy metabolism. Their activity largely depends upon the concentration of cellular AMP which is increased under conditions of low energy or metabolic stress. AMP-activated protein kinases modify enzymes involved in LIPID METABOLISM, which in turn provide substrates needed to convert AMP into ATP.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.Receptor, Insulin: A cell surface receptor for INSULIN. It comprises a tetramer of two alpha and two beta subunits which are derived from cleavage of a single precursor protein. The receptor contains an intrinsic TYROSINE KINASE domain that is located within the beta subunit. Activation of the receptor by INSULIN results in numerous metabolic changes including increased uptake of GLUCOSE into the liver, muscle, and ADIPOSE TISSUE.Cytosol: Intracellular fluid from the cytoplasm after removal of ORGANELLES and other insoluble cytoplasmic components.Transcriptional Activation: Processes that stimulate the GENETIC TRANSCRIPTION of a gene or set of genes.Cell Survival: The span of viability of a cell characterized by the capacity to perform certain functions such as metabolism, growth, reproduction, some form of responsiveness, and adaptability.Protein Kinase C-delta: A ubiquitously expressed protein kinase that is involved in a variety of cellular SIGNAL PATHWAYS. Its activity is regulated by a variety of signaling protein tyrosine kinase.Cyclic AMP Response Element-Binding Protein: A protein that has been shown to function as a calcium-regulated transcription factor as well as a substrate for depolarization-activated CALCIUM-CALMODULIN-DEPENDENT PROTEIN KINASES. This protein functions to integrate both calcium and cAMP signals.NF-kappa B: Ubiquitous, inducible, nuclear transcriptional activator that binds to enhancer elements in many different cell types and is activated by pathogenic stimuli. The NF-kappa B complex is a heterodimer composed of two DNA-binding subunits: NF-kappa B1 and relA.Electrophoresis, Gel, Two-Dimensional: Electrophoresis in which a second perpendicular electrophoretic transport is performed on the separate components resulting from the first electrophoresis. This technique is usually performed on polyacrylamide gels.Ribosomal Protein S6 Kinases, 70-kDa: A family of ribosomal protein S6 kinases that are considered the major physiological kinases for RIBOSOMAL PROTEIN S6. Unlike RIBOSOMAL PROTEIN S6 KINASES, 90KDa the proteins in this family are sensitive to the inhibitory effects of RAPAMYCIN and contain a single kinase domain. They are referred to as 70kDa proteins, however ALTERNATIVE SPLICING of mRNAs for proteins in this class also results in 85kDa variants being formed.Calcium-Calmodulin-Dependent Protein Kinase Type 2: A multifunctional calcium-calmodulin-dependent protein kinase subtype that occurs as an oligomeric protein comprised of twelve subunits. It differs from other enzyme subtypes in that it lacks a phosphorylatable activation domain that can respond to CALCIUM-CALMODULIN-DEPENDENT PROTEIN KINASE KINASE.Proto-Oncogene Proteins c-fyn: Src-family kinases that associate with T-CELL ANTIGEN RECEPTOR and phosphorylate a wide variety of intracellular signaling molecules.Phospholipase C gamma: A phosphoinositide phospholipase C subtype that is primarily regulated by PROTEIN-TYROSINE KINASES. It is structurally related to PHOSPHOLIPASE C DELTA with the addition of SRC HOMOLOGY DOMAINS and pleckstrin homology domains located between two halves of the CATALYTIC DOMAIN.tau Proteins: Microtubule-associated proteins that are mainly expressed in neurons. Tau proteins constitute several isoforms and play an important role in the assembly of tubulin monomers into microtubules and in maintaining the cytoskeleton and axonal transport. Aggregation of specific sets of tau proteins in filamentous inclusions is the common feature of intraneuronal and glial fibrillar lesions (NEUROFIBRILLARY TANGLES; NEUROPIL THREADS) in numerous neurodegenerative disorders (ALZHEIMER DISEASE; TAUOPATHIES).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.Mice, Inbred C57BLMyosin-Light-Chain Kinase: An enzyme that phosphorylates myosin light chains in the presence of ATP to yield myosin-light chain phosphate and ADP, and requires calcium and CALMODULIN. The 20-kDa light chain is phosphorylated more rapidly than any other acceptor, but light chains from other myosins and myosin itself can act as acceptors. The enzyme plays a central role in the regulation of smooth muscle contraction.Glucose: A primary source of energy for living organisms. It is naturally occurring and is found in fruits and other parts of plants in its free state. It is used therapeutically in fluid and nutrient replacement.RNA Interference: A gene silencing phenomenon whereby specific dsRNAs (RNA, DOUBLE-STRANDED) trigger the degradation of homologous mRNA (RNA, MESSENGER). The specific dsRNAs are processed into SMALL INTERFERING RNA (siRNA) which serves as a guide for cleavage of the homologous mRNA in the RNA-INDUCED SILENCING COMPLEX. DNA METHYLATION may also be triggered during this process.Active Transport, Cell Nucleus: Gated transport mechanisms by which proteins or RNA are moved across the NUCLEAR MEMBRANE.Type C Phospholipases: A subclass of phospholipases that hydrolyze the phosphoester bond found in the third position of GLYCEROPHOSPHOLIPIDS. Although the singular term phospholipase C specifically refers to an enzyme that catalyzes the hydrolysis of PHOSPHATIDYLCHOLINE (EC 3.1.4.3), it is commonly used in the literature to refer to broad variety of enzymes that specifically catalyze the hydrolysis of PHOSPHATIDYLINOSITOLS.ChromonesCytoskeleton: The network of filaments, tubules, and interconnecting filamentous bridges which give shape, structure, and organization to the cytoplasm.Cell Movement: The movement of cells from one location to another. Distinguish from CYTOKINESIS which is the process of dividing the CYTOPLASM of a cell.Protein Isoforms: Different forms of a protein that may be produced from different GENES, or from the same gene by ALTERNATIVE SPLICING.Tumor Suppressor Proteins: Proteins that are normally involved in holding cellular growth in check. Deficiencies or abnormalities in these proteins may lead to unregulated cell growth and tumor development.Phosphotransferases (Alcohol Group Acceptor): A group of enzymes that transfers a phosphate group onto an alcohol group acceptor. EC 2.7.1.MorpholinesNerve Tissue ProteinsStaurosporine: An indolocarbazole that is a potent PROTEIN KINASE C inhibitor which enhances cAMP-mediated responses in human neuroblastoma cells. (Biochem Biophys Res Commun 1995;214(3):1114-20)Phosphoamino Acids: Amino acids that contain phosphorus as an integral part of the molecule.DNA Primers: Short sequences (generally about 10 base pairs) of DNA that are complementary to sequences of messenger RNA and allow reverse transcriptases to start copying the adjacent sequences of mRNA. Primers are used extensively in genetic and molecular biology techniques.Protein Kinase C-alpha: A cytoplasmic serine threonine kinase involved in regulating CELL DIFFERENTIATION and CELLULAR PROLIFERATION. Overexpression of this enzyme has been shown to promote PHOSPHORYLATION of BCL-2 PROTO-ONCOGENE PROTEINS and chemoresistance in human acute leukemia cells.Janus Kinase 2: A Janus kinase subtype that is involved in signaling from GROWTH HORMONE RECEPTORS; PROLACTIN RECEPTORS; and a variety of CYTOKINE RECEPTORS such as ERYTHROPOIETIN RECEPTORS and INTERLEUKIN RECEPTORS. Dysregulation of Janus kinase 2 due to GENETIC TRANSLOCATIONS have been associated with a variety of MYELOPROLIFERATIVE DISORDERS.Calmodulin: A heat-stable, low-molecular-weight activator protein found mainly in the brain and heart. The binding of calcium ions to this protein allows this protein to bind to cyclic nucleotide phosphodiesterases and to adenyl cyclase with subsequent activation. Thereby this protein modulates cyclic AMP and cyclic GMP levels.rho-Associated Kinases: A group of intracellular-signaling serine threonine kinases that bind to RHO GTP-BINDING PROTEINS. They were originally found to mediate the effects of rhoA GTP-BINDING PROTEIN on the formation of STRESS FIBERS and FOCAL ADHESIONS. Rho-associated kinases have specificity for a variety of substrates including MYOSIN-LIGHT-CHAIN PHOSPHATASE and LIM KINASES.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.Ethers, Cyclic: Compounds of the general formula R-O-R arranged in a ring or crown formation.Oxazoles: Five-membered heterocyclic ring structures containing an oxygen in the 1-position and a nitrogen in the 3-position, in distinction from ISOXAZOLES where they are at the 1,2 positions.Ataxia Telangiectasia Mutated Proteins: A group of PROTEIN-SERINE-THREONINE KINASES which activate critical signaling cascades in double strand breaks, APOPTOSIS, and GENOTOXIC STRESS such as ionizing ultraviolet A light, thereby acting as a DNA damage sensor. These proteins play a role in a wide range of signaling mechanisms in cell cycle control.Cell Adhesion: Adherence of cells to surfaces or to other cells.MaleimidesButadienes: Four carbon unsaturated hydrocarbons containing two double bonds.Genistein: An isoflavonoid derived from soy products. It inhibits PROTEIN-TYROSINE KINASE and topoisomerase-II (DNA TOPOISOMERASES, TYPE II); activity and is used as an antineoplastic and antitumor agent. Experimentally, it has been shown to induce G2 PHASE arrest in human and murine cell lines and inhibits PROTEIN-TYROSINE KINASE.Microfilament Proteins: Monomeric subunits of primarily globular ACTIN and found in the cytoplasmic matrix of almost all cells. They are often associated with microtubules and may play a role in cytoskeletal function and/or mediate movement of the cell or the organelles within the cell.MAP Kinase Kinase 1: An abundant 43-kDa mitogen-activated protein kinase kinase subtype with specificity for MITOGEN-ACTIVATED PROTEIN KINASE 1 and MITOGEN-ACTIVATED PROTEIN KINASE 3.Myosin-Light-Chain Phosphatase: A phosphoprotein phosphatase that is specific for MYOSIN LIGHT CHAINS. It is composed of three subunits, which include a catalytic subunit, a myosin binding subunit, and a third subunit of unknown function.Pyridines: Compounds with a six membered aromatic ring containing NITROGEN. The saturated version is PIPERIDINES.STAT1 Transcription Factor: A signal transducer and activator of transcription that mediates cellular responses to INTERFERONS. Stat1 interacts with P53 TUMOR SUPPRESSOR PROTEIN and regulates expression of GENES involved in growth control and APOPTOSIS.Proto-Oncogene Proteins c-raf: A ubiquitously expressed raf kinase subclass that plays an important role in SIGNAL TRANSDUCTION. The c-raf Kinases are MAP kinase kinase kinases that have specificity for MAP KINASE KINASE 1 and MAP KINASE KINASE 2.Glutathione Transferase: A transferase that catalyzes the addition of aliphatic, aromatic, or heterocyclic FREE RADICALS as well as EPOXIDES and arene oxides to GLUTATHIONE. Addition takes place at the SULFUR. It also catalyzes the reduction of polyol nitrate by glutathione to polyol and nitrite.Eukaryotic Initiation Factor-4E: A peptide initiation factor that binds specifically to the 5' MRNA CAP STRUCTURE of MRNA in the CYTOPLASM. It is a component of the trimeric complex EIF4F.DNA Damage: Injuries to DNA that introduce deviations from its normal, intact structure and which may, if left unrepaired, result in a MUTATION or a block of DNA REPLICATION. These deviations may be caused by physical or chemical agents and occur by natural or unnatural, introduced circumstances. They include the introduction of illegitimate bases during replication or by deamination or other modification of bases; the loss of a base from the DNA backbone leaving an abasic site; single-strand breaks; double strand breaks; and intrastrand (PYRIMIDINE DIMERS) or interstrand crosslinking. Damage can often be repaired (DNA REPAIR). If the damage is extensive, it can induce APOPTOSIS.Myocardium: The muscle tissue of the HEART. It is composed of striated, involuntary muscle cells (MYOCYTES, CARDIAC) connected to form the contractile pump to generate blood flow.NIH 3T3 Cells: A continuous cell line of high contact-inhibition established from NIH Swiss mouse embryo cultures. The cells are useful for DNA transfection and transformation studies. (From ATCC [Internet]. Virginia: American Type Culture Collection; c2002 [cited 2002 Sept 26]. Available from http://www.atcc.org/)

Membrane-tethered Drosophila Armadillo cannot transduce Wingless signal on its own. (1/72374)

Drosophila Armadillo and its vertebrate homolog beta-catenin are key effectors of Wingless/Wnt signaling. In the current model, Wingless/Wnt signal stabilizes Armadillo/beta-catenin, which then accumulates in nuclei and binds TCF/LEF family proteins, forming bipartite transcription factors which activate transcription of Wingless/Wnt responsive genes. This model was recently challenged. Overexpression in Xenopus of membrane-tethered beta-catenin or its paralog plakoglobin activates Wnt signaling, suggesting that nuclear localization of Armadillo/beta-catenin is not essential for signaling. Tethered plakoglobin or beta-catenin might signal on their own or might act indirectly by elevating levels of endogenous beta-catenin. We tested these hypotheses in Drosophila by removing endogenous Armadillo. We generated a series of mutant Armadillo proteins with altered intracellular localizations, and expressed these in wild-type and armadillo mutant backgrounds. We found that membrane-tethered Armadillo cannot signal on its own; however it can function in adherens junctions. We also created mutant forms of Armadillo carrying heterologous nuclear localization or nuclear export signals. Although these signals alter the subcellular localization of Arm when overexpressed in Xenopus, in Drosophila they have little effect on localization and only subtle effects on signaling. This supports a model in which Armadillo's nuclear localization is key for signaling, but in which Armadillo intracellular localization is controlled by the availability and affinity of its binding partners.  (+info)

Cell polarization: chemotaxis gets CRACKing. (2/72374)

An early stage in the establishment of cell polarity during chemotaxis of Dictyostelium dicoideum has been identified by a recent study; the new results also show that the development of cell polarity does not rely upon cytoskeletal rearrangement, and may use a spatial sensing mechanism.  (+info)

The hematopoietic-specific adaptor protein gads functions in T-cell signaling via interactions with the SLP-76 and LAT adaptors. (3/72374)

BACKGROUND: The adaptor protein Gads is a Grb2-related protein originally identified on the basis of its interaction with the tyrosine-phosphorylated form of the docking protein Shc. Gads protein expression is restricted to hematopoietic tissues and cell lines. Gads contains a Src homology 2 (SH2) domain, which has previously been shown to have a similar binding specificity to that of Grb2. Gads also possesses two SH3 domains, but these have a distinct binding specificity to those of Grb2, as Gads does not bind to known Grb2 SH3 domain targets. Here, we investigated whether Gads is involved in T-cell signaling. RESULTS: We found that Gads is highly expressed in T cells and that the SLP-76 adaptor protein is a major Gads-associated protein in vivo. The constitutive interaction between Gads and SLP-76 was mediated by the carboxy-terminal SH3 domain of Gads and a 20 amino-acid proline-rich region in SLP-76. Gads also coimmunoprecipitated the tyrosine-phosphorylated form of the linker for activated T cells (LAT) adaptor protein following cross-linking of the T-cell receptor; this interaction was mediated by the Gads SH2 domain. Overexpression of Gads and SLP-76 resulted in a synergistic augmentation of T-cell signaling, as measured by activation of nuclear factor of activated T cells (NFAT), and this cooperation required a functional Gads SH2 domain. CONCLUSIONS: These results demonstrate that Gads plays an important role in T-cell signaling via its association with SLP-76 and LAT. Gads may promote cross-talk between the LAT and SLP-76 signaling complexes, thereby coupling membrane-proximal events to downstream signaling pathways.  (+info)

Tyrosine phosphorylation is required for actin-based motility of vaccinia but not Listeria or Shigella. (4/72374)

Studies of the actin-based motility of pathogens have provided important insights into the events occurring at the leading edge of motile cells [1] [2] [3]. To date, several actin-cytoskeleton-associated proteins have been implicated in the motility of Listeria or Shigella: vasodilator-stimulated phosphoprotein (VASP), vinculin and the actin-related protein complex of Arp2 and Arp3 [4] [5] [6] [7]. To further investigate the underlying mechanism of actin-tail assembly, we examined the localization of components of the actin cytoskeleton including Arp3, VASP, vinculin and zyxin during vaccinia, Listeria and Shigella infections. The most striking difference between the systems was that a phosphotyrosine signal was observed only at the site of vaccinia actin-tail assembly. Micro-injection experiments demonstrated that a phosphotyrosine protein plays an important role in vaccinia actin-tail formation. In addition, we observed a phosphotyrosine signal on clathrin-coated vesicles that have associated actin-tail-like structures and on endogenous vesicles in Xenopus egg extracts which are able to nucleate actin tails [8] [9]. Our observations indicate that a host phosphotyrosine protein is required for the nucleation of actin filaments by vaccinia and suggest that this phosphoprotein might be associated with cellular membranes that can nucleate actin.  (+info)

Intracellular signalling: PDK1--a kinase at the hub of things. (5/72374)

Phosphoinositide-dependent kinase 1 (PDK1) is at the hub of many signalling pathways, activating PKB and PKC isoenzymes, as well as p70 S6 kinase and perhaps PKA. PDK1 action is determined by colocalization with substrate and by target site availability, features that may enable it to operate in both resting and stimulated cells.  (+info)

Prodigious substrate specificity of AAC(6')-APH(2"), an aminoglycoside antibiotic resistance determinant in enterococci and staphylococci. (6/72374)

BACKGROUND: High-level gentamicin resistance in enterococci and staphylococci is conferred by AAC(6')-APH(2"), an enzyme with 6'-N-acetyltransferase and 2"-O-phosphotransferase activities. The presence of this enzyme in pathogenic gram-positive bacteria prevents the successful use of gentamicin C and most other aminoglycosides as therapeutic agents. RESULTS: In an effort to understand the mechanism of aminoglycoside modification, we expressed AAC(6')-APH(2") in Bacillus subtilis. The purified enzyme is monomeric with a molecular mass of 57 kDa and displays both the expected aminoglycoside N-acetyltransferase and O-phosphotransferase activities. Structure-function analysis with various aminoglycosides substrates reveals an enzyme with broad specificity in both enzymatic activities, accounting for AAC(6')-APH(2")'s dramatic negative impact on clinical aminoglycoside therapy. Both lividomycin A and paromomycin, aminoglycosides lacking a 6'-amino group, were acetylated by AAC(6')-APH(2"). The infrared spectrum of the product of paromomycin acetylation yielded a signal consistent with O-acetylation. Mass spectral and nuclear magnetic resonance analysis of the products of neomycin phosphorylation indicated that phosphoryl transfer occurred primarily at the 3'-OH of the 6-aminohexose ring A, and that some diphosphorylated material was also present with phosphates at the 3'-OH and the 3"'-OH of ring D, both unprecedented observations for this enzyme. Furthermore, the phosphorylation site of lividomycin A was determined to be the 5"-OH of the pentose ring C. CONCLUSIONS: The bifunctional AAC(6')-APH(2") has the capacity to inactivate virtually all clinically important aminoglycosides through N- and O-acetylation and phosphorylation of hydroxyl groups. The extremely broad substrate specificity of this enzyme will impact on future development of aminoglycosides and presents a significant challenge for antibiotic design.  (+info)

High-throughput screening of small molecules in miniaturized mammalian cell-based assays involving post-translational modifications. (7/72374)

BACKGROUND: Fully adapting a forward genetic approach to mammalian systems requires efficient methods to alter systematically gene products without prior knowledge of gene sequences, while allowing for the subsequent characterization of these alterations. Ideally, these methods would also allow function to be altered in a temporally controlled manner. RESULTS: We report the development of a miniaturized cell-based assay format that enables a genetic-like approach to understanding cellular pathways in mammalian systems using small molecules, rather than mutations, as the source of gene-product alterations. This whole-cell immunodetection assay can sensitively detect changes in specific cellular macromolecules in high-density arrays of mammalian cells. Furthermore, it is compatible with screening large numbers of small molecules in nanoliter to microliter culture volumes. We refer to this assay format as a 'cytoblot', and demonstrate the use of cytoblotting to monitor biosynthetic processes such as DNA synthesis, and post-translational processes such as acetylation and phosphorylation. Finally, we demonstrate the applicability of these assays to natural-product screening through the identification of marine sponge extracts exhibiting genotype-specific inhibition of 5-bromodeoxyuridine incorporation and suppression of the anti-proliferative effect of rapamycin. CONCLUSIONS: We show that cytoblots can be used for high-throughput screening of small molecules in cell-based assays. Together with small-molecule libraries, the cytoblot assay can be used to perform chemical genetic screens analogous to those used in classical genetics and thus should be applicable to understanding a wide variety of cellular processes, especially those involving post-transitional modifications.  (+info)

Tyrosine phosphorylation and complex formation of Cbl-b upon T cell receptor stimulation. (8/72374)

Cbl-b, a mammalian homolog of Cbl, consists of an N-terminal region (Cbl-b-N) highly homologous to oncogenic v-Cbl, a Ring finger, and a C-terminal region containing multiple proline-rich stretches and potential tyrosine phosphorylation sites. In the present study, we demonstrate that upon engagement of the T cell receptor (TCR), endogenous Cbl-b becomes rapidly tyrosine-phosphorylated. In heterogeneous COS-1 cells, Cbl-b was phosphorylated on tyrosine residues by both Syk- (Syk/Zap-70) and Src- (Fyn/Lck) family kinases, with Syk kinase inducing the most prominent effect. Syk associates and phosphorylates Cbl-b in Jurkat T cells. A Tyr-316 Cbl-binding site in Syk was required for the association with and for the maximal tyrosine phosphorylation of Cbl-b. Mutation at a loss-of-function site (Gly-298) in Cbl-b-N disrupts its interaction with Syk. Cbl-b constitutively binds Grb2 and becomes associated with Crk-L upon TCR stimulation. The Grb2- and the Crk-L-binding regions were mapped to the C-terminus of Cbl-b. The Crk-L-binding sites were further determined to be Y655DVP and Y709KIP, with the latter being the primary binding site. Taken together, these results implicate that Cbl-b is involved in TCR-mediated intracellular signaling pathways.  (+info)

Many cytokines, hormones, and growth factors activate Janus kinases to tyrosine phosphorylate select members of the Stat transcription factors. For full transcriptional activation, Stat1 and Stat3 also require phosphorylation of a conserved serine residue within a mitogen-activated protein kinase phosphorylation consensus site. On the other hand, two recently identified and highly homologous Stat5a and Stat5b proteins lack this putative mitogen-activated protein kinase phosphorylation site. The present study set out to establish whether Stat5a and Stat5b are under the control of an interleukin-2 (IL2)-activated Stat5 serine kinase. We now report that IL2 stimulated marked phosphorylation of serine and tyrosine residues of both Stat5a and Stat5b in human T lymphocytes and in several IL2-responsive lymphocytic cell lines. No Stat5a/b phosphothreonine was detected. Phosphoamino acid analysis also revealed that Stat5a/b phosphotyrosine levels were maximized within 1-5 min of IL2 stimulation, whereas ...
PKA phosphorylation increases the tyrosine kinase activity of Csk towards an endogenous substrate. Tyrosine phosphorylation of heat-inactivated (65°C for 10 mi
Post-translational modification (PTM) of proteins regulates many biological phenomena [1]. Among the several kinds of PTM, phosphorylation affects enzymatic activity, conformations, interactions, degradation, and localization of proteins, among other effects [2-4]; one of the critical roles of phosphorylation is in the control of protein signaling [5]. More than 500 protein kinases are thought to regulate protein signaling in humans [6]. In protein signaling, various reaction cascades transmit and amplify signals in a highly regulated manner by means of reversible site-specific protein phosphorylation [5]. Kinases recognize the specific surrounding sequences of phosphosites when they phosphorylate their targets, and the majority of the identified kinases are thought to have their own unique target sequences, which are known as "motif sequences" [7].. Liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS), combined with phosphopeptide enrichment technology [8], is a powerful ...
In vitro phosphorylation of the regulatory subunit of yeast cAMP-dependent protein kinase was studied. The cAMP-binding regulatory subunit (R subunit) can be multiply phosphorylated. Three distinct phosphorylation sites were inferred from the different ATP concentrations required for phosphorylation and from the presence of two discrete mobility shifts in NaDodSO4/polyacrylamide gel electrophoresis of the R subunit on phosphorylation. Limited tryptic digestion of the phosphorylated R subunit showed that a Mr 37,000 cAMP-binding peptide contained one of the phosphorylation sites and that a separate Mr 12,000 peptide contained another phosphorylation site. The yeast R subunit is therefore similar to the type II R subunit of mammalian origin, although it has a larger Mr (64,000 vs. 58,000) and is multiply phosphorylated. In vivo, both phosphorylated and unphosphorylated forms of the R subunit were found in cells grown in lactate or to stationary phase in 1.5% glucose, while cells grown in 5% ...
Cardiac Na+/K+ ATPase plays a pivotal role in maintaining the Na+ transmembrane gradient which is essential for normal cardiac function. Elevation of intracellular Na+ ([Na+]i) is a key contributor to contractile and electrical dysfunction in a variety of pathologies. Phospholemman (PLM), is the cardiac specific member of the FXYD family of small membrane spanning proteins, and forms a complex with Na+/K+ ATPase pump. PLM regulates the pump by exerting a tonic inhibition which is relieved by PKA or PKC phosphorylation at 3 serine (Ser)/threonine (Thr) residues in its cytoplasmic tail (Ser63, Ser68, Thr/Ser69). Phosphorylation at any of these sites results in disinhibition of the pump and even active stimulation. The work described in this thesis investigates the role of PLM in regulating the Na+/K+ ATPase and the subsequent effect on [Na+]i. A new mouse model, PLM3SA, has been created by mutating all 3 Ser residues to alanine (Ala) rendering the protein unphosphorylatable. This inability to ...
TY - JOUR. T1 - Phosphoproteomics identified Endofin, DCBLD2, and KIAA0582 as novel tyrosine phosphorylation targets of EGF signaling and Iressa in human cancer cells. AU - Chen, Yunhao. AU - Low, Teck Yew. AU - Choong, Lee Yee. AU - Ray, Rajarshi Sankar. AU - Tan, Yee Ling. AU - Toy, Weiyi. AU - Lin, Qingsong. AU - Boon, Keong Ang. AU - Chee, Hong Wong. AU - Lim, Simin. AU - Li, Bin. AU - Hew, Choy Leong. AU - Sze, Newman Siu Kwan. AU - Druker, Brian. AU - Lim, Yoon Pin. PY - 2007/7. Y1 - 2007/7. N2 - With the completion of the human genome project, analysis of enriched phosphotyrosyl proteins from epidermal growth factor (EGF)-induced phosphotyrosine proteome permits the identification of novel downstream substrates of the EGF receptor (EGFR). Using cICAT-based LC-MS/MS method, we identified and relatively quantified the tyrosine phosphorylation levels of 21 proteins between control and EGF-treated A431 human cervical cancer cells. Of these, Endofin, DCBLD2, and KIAA0582 were validated to be ...
Oscillatory protein phosphorylation regulates the major phase transitions of the cell division cycle. The overall amount of phosphorylation is especially high during mitosis (37, 38), and several large-scale studies have identified sets of phosphorylation sites present during mitosis (8, 11-13, 39). These studies, although mostly performed on a "phosphoproteome" scale, are still far from complete due to the complexity and variance in protein abundance within the proteome (40). Because phosphoproteomic studies usually rely on phosphopeptide enrichment, the information about the unphosphorylated proteins is lost, and it thus remains difficult to estimate the protein coverage in these studies. Here, we have taken a complementary approach to analyze mitotic phosphorylation within purified mitotic protein complexes. The much lower sample complexity allowed simultaneous analysis of phosphorylated and unphosphorylated peptides to obtain a measure of sequence coverage for each analyzed protein and ...
In eukaryotes, hundreds of protein kinases (PKs) specifically and precisely modify thousands of substrates at specific amino acid residues to faithfully orchestrate numerous biological processes, and reversibly determine the cellular dynamics and plasticity. Although over 100,000 phosphorylation sites (p-sites) have been experimentally identified from phosphoproteomic studies, the regulatory PKs for most of these sites still remain to be characterized. Here, we present a novel software package of iGPS for the prediction of in vivo site-specific kinase-substrate relations mainly from the phosphoproteomic data. By critical evaluations and comparisons, the performance of iGPS is satisfying and better than other existed tools. Based on the prediction results, we modeled protein phosphorylation networks and observed that the eukaryotic phospho-regulation is poorly conserved at the site and substrate levels. With an integrative procedure, we conducted a large-scale phosphorylation analysis of human ...
β-Catenin phosphorylation plays important roles in modulating its functions, but the effects of different phosphorylated forms of β-catenin in response to heterocellular interaction are unclear. Here we investigated whether distinct modes of phosphorylation on β-catenin could be triggered through heterocellular interactions between endothelial cells (ECs) and smooth muscle cells (SMCs), and the consequent modulation of EC functions. ECs were cocultured with SMCs to initiate direct contact and paracrine interaction. EC-SMC coculture induced EC β-catenin phosphorylations simultaneously at tyrosine 142 (Tyr142) and serine 45/threonine 41 (Ser45/Thr41) at the cytoplasm/nuclei and the membrane, respectively. Treating ECs with SMC-conditional medium induced β-catenin phosphorylation only at Ser45/Thr41. These findings indicate that different phosphorylation effects of EC-SMC coculture were induced through heterocellular direct contact and paracrine effects, respectively. Using specific blocking ...
APP is phosphorylated at multiple sites in the 47 amino acid C-terminal cytoplasmic domain (Suzuki et al., 1994). Phosphorylation of Thr668 is particularly important, because it induces conformational changes that affect APP function and metabolism (Ando et al., 2001; Ramelot and Nicholson, 2001). To understand the mechanism of APP phosphorylation at Thr668 in neuronal cells, in this study, we investigated the role of the kinases Cdk5 and JNK and of their scaffolding and activating proteins. Using dominant-negative strategies and small molecule inhibitors, we found that JNK, not Cdk5, phosphorylates APP in differentiating neuronal cells. By preventing the interaction of JIP-1 with JNK or APP, we established that this JNK scaffolding, APP-binding protein does not participate in APP phosphorylation in neurons under normal physiological conditions. Importantly, we found that JIP-3, another JNK adaptor protein, which does not directly interact with APP, participates in the generation of a large ...
TY - JOUR. T1 - Tyrosine phosphorylation controls Runx2-mediated subnuclear targeting of YAP to repress transcription. AU - Zaidi, Sayyed K.. AU - Sullivan, Andrew J.. AU - Medina, Ricardo. AU - Ito, Yoshiaki. AU - van Wijnen, Andre J. AU - Stein, Janet L.. AU - Lian, Jane B.. AU - Stein, Gary S.. PY - 2004/2/25. Y1 - 2004/2/25. N2 - Src/Yes tyrosine kinase signaling contributes to the regulation of bone homeostasis and inhibits osteoblast activity. Here we show that the endogenous Yes-associated protein (YAP), a mediator of Src/Yes signaling, interacts with the native Runx2 protein, an osteoblast-related transcription factor, and suppresses Runx2 transcriptional activity in a dose-dependent manner. Runx2, through its PY motif, recruits YAP to subnuclear domains in situ and to the osteocalcin (OC) gene promoter in vivo. Inhibition of Src/Yes kinase blocks tyrosine phosphorylation of YAP and dissociates endogenous Runx2-YAP complexes. Consequently, recruitment of the YAP co-repressor to ...
The splicing factor Sf3b is an integral part of U2 snRNP and plays an essential role during spliceosome assembly and recognition of the introns branch point. One of the components of SF3b, SF3b1, is known to be reversibly phosphorylated during splicing catalysis [3], suggesting that protein kinases play a role in the regulation of splicing. Previous studies have shown that cyclin E/CDK2 complexes associate with spliceosomal proteins in vivo, and that CDK2 phosphorylates SF3b1 in vitro [12, 22]. Here we provide evidence that the protein kinase DYRK1A phosphorylates SF3b1 in vitro and in vivo.. The N-terminal part of Sf3b1 harbours a large number of Thr/Pro dipeptide motifs within a 240-amino acid region preceding the carboxyterminal repeat domain (Fig. 1). Both DYRK1A and CDK2 are proline-directed kinases, i.e. they phosphorylate serine or threonine residues followed by a proline residue [15, 23]. It has been shown that cyclin E/CDK2 phosphorylates SF3b1 in vitro at multiple sites within the ...
1538 Because of its versatility (all types of substrates), robustness (Z,0.8) , and rapid performance (10 minutes), and its ease of use, the luminescence based Kinase GloTM, Kinase Glo PlusTM, and now Kinase Glo Max assay platform have gained wide acceptance in many drug screening programs for protein kinase inhibitors. It is applicable to all kinds of kinase substrates regardless of their nature with no prior modification (peptides, protein, polymer, lipids, and sugars). It also detects additional phosphorylation sites of already existing phosphopeptide substrates by enzymes such as GSK-3 and CK1, and monitors the activity of kinases phosphorylating their substrates on multiple sites. Since the linear range of ATP is extended to 500 µM, it is feasible to screen libraries for compounds that are not only competitive with ATP but also for those that are non competitive which broaden the selection of inhibitors of both serine/threonine protein kinases as well as tyrosine protein kinases. The ...
The intracellular localization of the S. cerevisiae transcription factor SWI5 is cell cycle dependent. The protein is nuclear in G1 cells but cytoplasmic in S, G2, and M phase cells. We have identified SWI5s nuclear localization signal (NLS) and show that it can confer cell cycle-dependent nuclear entry to a heterologous protein. Located within or close to the NLS are three serine residues, mutation of which results in constitutive nuclear entry. These residues are phosphorylated in a cell cycle-dependent manner in vivo, being phosphorylated when SWI5 is in the cytoplasm and dephosphorylated when it is in the nucleus. As all three serines are phosphorylated by purified CDC28-dependent H1 kinase activity in vitro, we propose a model in which the CDC28 kinase acts directly to control nuclear entry of SWI5.
Tuberin exists as a phosphoprotein, the target of both serine/threonine and tyrosine kinases (31) . Our data are consistent with that of others, which indicate that at least one of these kinases is Akt, a downstream effector of the PI3K signaling pathway (33, 34, 35, 36) . Tuberin contains three recognition sites for Akt that are also potential 14-3-3 binding sites. Using a novel protein domain array, a tuberin peptide containing Ser939 bound to 14-3-3 in a phosphorylation-specific manner. All seven 14-3-3 isoforms recognized tuberin in GST-pull-down assays, and at least one of these, 14-3-3γ, recognized tuberin in fibroblasts (NIH3T3) as well as mammary (MCF-7) and kidney epithelial cells (TRKE) from mouse, human, and rat, respectively. The interaction between 14-3-3γ and tuberin was effectively competed with phosphorylated but not unphosphorylated Ser939 peptide. Endogenous tuberin could also be coimmunoprecipitated with 14-3-3 in kidney epithelial cell lysates. While in submission, our data ...
Downstream of tyrosine kinase (Dok) proteins Dok-1 and Dok-2 are involved in T cell homeostasis maintenance. Dok protein tyrosine phosphorylation plays a key role in establishing negative feedback loops of T cell signaling. These structurally related adapter molecules contain a pleckstrin homology (PH) domain generally acting as a lipid/protein-interacting module. We show that the presence of this PH domain is necessary for the tyrosine phosphorylation of Dok proteins and their negative functions in T cells. We find that Dok-1/Dok-2 PH domains bind in vitro to the rare phosphoinositide species, phosphatidylinositol 5-phosphate (PtdIns5P). Dok tyrosine phosphorylation correlates with PtdIns5P production in T cells upon TCR triggering. Furthermore, we demonstrate that PtdIns5P increase regulates Dok tyrosine phosphorylation in vivo. Together, our data identify a novel lipid mediator in T cell signaling and suggest that PH-PtdIns5P interactions regulate T cell responses.
An hepatocyte cell-adhesion molecule (cell-CAM105) was recently shown to be identical with the liver plasma-membrane ecto-ATPase. This protein has structural features of the immunoglobulin superfamily and is homologous with carcinoembryonic antigen proteins. We have cloned a cDNA encoding a new form of the cell-CAM105 which is a variant of the previously isolated clone. In addition to having a shorter cytoplasmic domain, the new isoform also has substitutions clustered in the first 130 amino acids of the extracellular domain. Both of these isoforms are expressed on the surface of hepatocytes with the shorter variant being the predominant form. The previously isolated cell-CAM105 (long form) has more potential phosphorylation sites than does the new isoform (short form). Both isoforms are found to be phosphorylated after incubation with [32P]phosphate in vitro, with the long form being phosphorylated to a significantly higher extent. This observed differential phosphorylation could be one of the ...
Immunoblot analysis. Synaptosomal samples were rapidly solubilized in 1-2% SDS (95°C), sonicated, and protein concentration was measured using BCA assay (Pierce, Rockford, IL), with bovine serum albumin as standard. Equal amounts of protein were subjected to SDS-PAGE and transferred onto nitrocellulose membranes. Immunoblots were done with 1:500 dilutions of the following phosphorylation state-specific antibodies: P-site 1 antibody (G-257), P-site 3 antibody (RU19), P-site 4/5 antibody (G-526), and P-site 6 antibody (G-555). The specificity of these antibodies for their respective sites has been characterized previously (Czernik et al., 1991; Jovanovic et al., 1996). Total synapsin I was detected by immunoblotting with synapsin I-specific antibody (G-486; 1:500 dilution). Primary incubations were followed by incubation with125I-labeled anti-rabbit IgG (1:500 dilution; Amersham Pharmacia Biotech, Little Chalfont, UK). Blots were exposed to a PhosphorImager screen, and quantification of ...
PINK1‐mediated phosphorylation of Ub at Ser65 has dramatic consequences for Ub structure, and key processes in the Ub system, namely Ub attachment and removal.. It could be expected that phosphorylation of Ub would change its surface properties due to the addition of a negative charge. The obtained high‐resolution crystal structure and solution studies agree that the majority of phosphoUb is structurally similar to wt Ub. To our amazement, NMR studies showed a second, minor conformation of phosphoUb, which is in slow exchange with the major conformation. Strikingly, the minor conformation shows distinct hydrogen bonding patterns and long‐range NOEs for its C‐terminal β5‐strand, which can only be structurally satisfied when this strand is shifted by two residues. Our phosphoUbretraCT model explains numerous observations and is structurally feasible due to the existence of four Leu‐Xaa repeats in the β5‐strand that would allow a shift of two residues without significantly ...
Phosphorylation is an important covalent post-translational modification (PTM) in cell signalling pathways. Protein phosphorylation is the reversible addition of a phosphate group to a protein or small molecule catalysed by protein kinases. Approximately one third of the 30,000 proteins encoded by the human genome contain covalently bound phosphate. The average protein kinase can add phosphates to 20 different proteins and the average protein phosphatase removes phosphate from 60 different proteins.
Cytoplasmic expression of claudin-1 in metastatic melanoma cells correlates to increased migration, and increased secretion of MMP-2 in a PKC dependent manner, whereas claudin-1 nuclear expressi...
We statement here for the first time the multiplexed quantitation of phosphorylation and protein expression based on a functionalized soluble nanopolymer. phosphorylation signals from protein manifestation changes thus providing a powerful tool to accurately profile cellular transmission transduction in healthy and disease cells. We anticipate broad applications of this new strategy in monitoring cellular signaling pathways and finding new signaling occasions. Protein phosphorylation one of the most ubiquitous post-translational adjustments continues to be implicated in the legislation of virtually all areas of a cells lifestyle. Aberrant phosphorylation dynamics inside the cell donate to the advancement and onset of several malignances.1 Therefore considerable work has been specialized in profiling proteins phosphorylation under Tm6sf1 different cellular circumstances. Currently most studies survey phosphorylation occasions that neglect to differentiate adjustments in phosphorylation from ...
Phospholamban (PLN) regulates myocyte calcium cycling by inhibiting the Ca2+ATPase SERCA2a. Protein kinase A (PKA) mediated phosphorylation attenuates PLN activity leading to enhanced calcium uptake rates and accelerated cardiac relaxation. In vivo, PLN is present in monomeric and pentameric form. It is believed that PKA primarily targets the PLN monomer. However, we found that a R9C mutant of PLN dominantly inhibits PLN phosphorylation only within the pentamer suggesting a significant role of the pentamer in determining phosphorylation and, thus, PLN activity.. To investigate the role of the pentamer in PLN phosphorylation and function, the sensitivity, kinetics and stoichiometry of phosphorylation were analyzed in monomeric and pentameric PLN mutants expressed in a human cell line (HEK293AD). We found an independent increase of phosphorylation for monomer and pentamer upon forskolin stimulation, both in a concentration and time-dependent manner. Intriguingly, phosphorylation signals of PLN ...
Procaspase-8, the zymogen type of the apoptosis-initiator caspase-8, undergoes phosphorylation following integrin-mediated cell connection to an extracellular matrix base. CrkII and Crk, each bearing an Src-homology 2 domains (SH2) and one or two Src homology 3 (SH3) websites, respectively. CrkL (and knockouts display cardiac and sensory crest flaws, ending in embryonic lethality.17,18 Here, we offer proof that caspase-8 interacts with the You will need2 domains of CrkL in a Src- and adhesion-dependent way, and that this connections stimulates cellular migration. Outcomes Caspase-8 interacts with CrkL SH2 domains We observed the de novo phosphorylation of many protein, in caspase-8 showing cells selectively, pursuing cell adhesion to fibronectin substrates. These included a phosphoprotein at ~37 kDa (Fig.?1A). To determine whether the phosphoprotein may end up being component of a complicated linked with the caspase, caspase-8 immunoprecipitations had been performed by us, solved the necessary ...
The B cell-restricted transmembrane glycoprotein CD22 is rapidly phosphorylated on tyrosine in response to cross-linking of the B cell antigen receptor, thereby generating phosphotyrosine motifs in the cytoplasmic domain which recruit intracellular effector proteins that contain Src homology 2 domains. By virtue of its interaction with these effector proteins CD22 modulates signal transduction through the B cell antigen receptor. To define further the molecular mechanism by which CD22 mediates its co-receptor function, phosphopeptide mapping experiments were conducted to determine which of the six tyrosine residues in the cytoplasmic domain are involved in recruitment of the stimulatory effector proteins phospholipase Cχ (PLCχ), phosphoinositide 3-kinase (PI3K), Grb2, and Syk. The results obtained indicate that the protein tyrosine kinase Syk interacts with multiple CD22- derived phosphopeptides in both immunoprecipitation and reverse Far Western assays. In contrast, the Grb2·Sos complex was ...
The invasion-promoting effect of ET-18-OMe on MCF-7/AZ cells suggests that ET-18-OMe initiates cSrc-mediated signalling in MCF-7/AZ cells, but not in the variant MCF-7/6 cells (Figure 1). Therefore the effect of ET-18-OMe on phosphorylation of Tyr397 of FAK, the autophosphorylation site of FAK, and Tyr416 of cSrc kinase was examined. Expression levels of FAK and cSrc in both cell lines were unchanged, but kinase activity of cSrc (Figures 2A, left-hand panel and 2B) and FAK (Figures 2A, left-hand panel and 2C) were greatly enhanced in MCF-7/AZ cells 5-10 min after treatment. There was no such activation of cSrc and FAK in MCF-7/6 cells (Figure 2A, right-hand panel). The use of cSrc kinase inhibitor, PP1, blocked activation of cSrc but not Tyr397 phosphorylation on FAK, suggesting that the autophosphorylation of FAK promotes activation of cSrc. Next, the cSrc-dependent tyrosine phosphorylation sites on FAK (Tyr576, Tyr861 and Tyr925) were assayed. Time-dependent phosphorylation of FAK on Tyr925 ...
Catalytic domain of the Protein Serine/Threonine Kinase, MAP/ERK kinase kinase 3. Serine/threonine kinases (STKs), MAP/ERK kinase kinase 3 (MEKK3) subfamily, catalytic (c) domain. STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. The MEKK3 subfamily is part of a larger superfamily that includes the catalytic domains of other protein STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase. MEKK3 is a mitogen-activated protein kinase (MAPK) kinase kinase (MAPKKK or MKKK or MAP3K), that phosphorylates and activates the MAPK kinase MEK5 (or MKK5), which in turn phosphorylates and activates extracellular signal-regulated kinase 5 (ERK5). The ERK5 cascade plays roles in promoting cell proliferation, differentiation, neuronal survival, and neuroprotection. MEKK3 plays an essential role in embryonic angiogenesis and early heart development. In addition, MEKK3 is ...
Many stimuli mediate activation and nuclear translocation of ERK (extracellular-signal-regulated kinase) by phosphorylation on the TEY (Thr-Glu-Tyr) motif. This is necessary to initiate transcriptional programmes controlling cellular responses, but the mechanisms that govern ERK nuclear targeting are unclear. Single-cell imaging approaches have done much to increase our understanding of input-output relationships in the ERK cascade, but few studies have addressed how the range of ERK phosphorylation responses observed in cell populations influences subcellular localization. Using automated microscopy to explore ERK regulation in single adherent cells, we find that nuclear localization responses increase in proportion to stimulus level, but not the level of TEY phosphorylation. This phosphorylation-unattributable nuclear localization response occurs in the presence of tyrosine phosphatase and protein synthesis inhibitors. It is also seen with a catalytically inactive ERK2-GFP (green fluorescent ...
We recently identified a novel adaptor protein, termed dual adaptor for phosphotyrosine and 3-phosphoinositides (DAPP1), that possesses a Src homology (SH2) domain and a pleckstrin homology (PH) domain. DAPP1 exhibits a high-affinity interaction with PtdIns(3,4,5)P3 and PtdIns(3,4)P2, which bind to the PH domain. In the present study we show that when DAPP1 is expressed in HEK-293 cells, the agonists insulin, insulin-like growth factor-1 and epidermal growth factor induce the phosphorylation of DAPP1 at Tyr139. Treatment of cells with phosphoinositide 3-kinase (PI 3-kinase) inhibitors or expression of a dominant-negative PI 3-kinase prevent phosphorylation of DAPP1 at Tyr139, and a PH-domain mutant of DAPP1, which does not interact with PtdIns(3,4,5)P3 or PtdIns(3,4)P2, is not phosphorylated at Tyr139 following agonist stimulation of cells. Overexpression of a constitutively active form of PI 3-kinase induced the phosphorylation of DAPP1 in unstimulated cells. We demonstrated that Tyr139 of ...
Interestingly, recent in vitro kinetic studies using recombinant active p38α expressed in Escherichia coli showed that p38 phosphorylates GST-ATF2 (amino acids 1-115) via a two‐step (double collision) mechanism, involving the dissociation of mono‐phosphorylated ATF2 Thr71 or Thr69 from the enzyme after the first phosphorylation step (Waas et al., 2001). Moreover, these authors found that mono‐phosphorylation of ATF2 Thr69 strongly reduces the phosphorylation rate of Thr71, whereas, in contrast, mono‐phosphorylation of Thr71 does not reduce the rate of Thr69 phosphorylation. Thus, efficient phosphorylation of ATF2 by recombinant E.coli‐expressed active p38 only occurs in the order Thr71→ Thr69 + 71 (Figure 7). This order of events also seems to occur in mitogen‐treated cells, as ERK, in contrast to p38, does not seem to mono‐phosphorylate Thr69 significantly (Figure 4C).. The fact that ERK does not double‐phosphorylate ATF2 Thr69 + 71 efficiently raises the question as to ...
Phosphorylation in the activation segment of protein kinases is a common mechanism of kinase regulation. However, activation loop phosphorylation of many kinases generally induces activating structural changes by repositioning key structural elements that permit substrate and cofactor binding and efficient catalysis (51). Although no common mechanism has been proposed for negative regulation of protein-Ser/Thr kinases, phosphorylation of several of the CDKs within the subdomain I GXGXXG motif at the Thr14 and Tyr15 (human CDK1 numbering) are known to be inhibitory (67-69), and acetylation of the ATP coordinating Lys has been shown to reduce the kinase activity of CDK9 (70).. Here, we establish for the first time that mimicking phosphorylation of PLK1 on Tyr217 in the P+1 loop completely inhibits detectable kinase activity, likely through inhibition of substrate binding, although we cannot formally rule out the possibility that the effect is due to the Glu substitution rather than a ...
Serine-proline or threonine-proline is minimally required for Cdk-dependent phosphorylation (Errico, 2010), and we see that Ascl1 undergoes cell cycle-dependent phosphorylation in Xenopus egg extracts on these sites (Fig. 1; supplementary material Fig. S2); a mutant in which SP sites have been mutated to alanine-proline shows a dramatic reduction in phosphorylation.. To determine whether Ascl1 can indeed act as a target for Cdks, we incubated Ascl1 protein with active recombinant cyclin/Cdk proteins. When wild-type Ascl1 was incubated with CyclinA/Cdk2, its migration on SDS-PAGE was significantly retarded, and a smear of slower-migrating Ascl1 protein indicates phosphorylation on more than one site (supplementary material Fig. S3). S-A Ascl1 in this assay shows markedly reduced retardation compared with wild-type Ascl1, demonstrating that phosphorylation of Ascl1 occurs on SP sites. It is interesting to note that in vitro when incubated with purified kinases, some phosphorylation of S-A Ascl1 ...
Clone REA134 recognizes AKT1, which is also known as protein kinase Bα. AKT1 is a serine/threonine protein kinase, belonging to the AKT family of kinases and like each AKT family member, contains an N-terminal pleckstrin homology (PH) domain, a central kinase domain, and a carboxyl-terminal regulatory domain with a hydrophobic motif (HM). Activation of AKT1 is achieved via phosphorylation at multiple sites, which take place in response to engagement of receptors such as platelet derived growth factor receptor (PDGF-R). Activated AKT1 further phosphorylates and alters the activity of several downstream substrates allowing AKT1 to play a vital role in various biological processes such as cell growth, survival, migration, and proliferation. Additional information: Clone REA134 displays negligible binding to Fc receptors. - Belgique
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If you have an antibody against the protein you investigate you can perform 1D IEF gels followed by western blots (see my current post). The blotting effiency is not very high because the proteins in the gel are not charged but I try to optimize (washing with SDS). With this method you can detect different phosphorylated forms of that protein. And if you have a suggestion about the respective kinase and are able to construct a mutant (Im working with bacteria...) the phosphorylated band should disapear if your suggestion is right ...
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T-lymphocytes play a crucial role in the immune response, both as direct effector cells and as regulatory cells that modulate the functions of other cell types. One of the earliest recognizable events after TCR stimulation is activation of LCK (p56lck) and FYN (p59fyn), which results in phosphorylation of tyrosine residues. Subsequently, ZAP70 tyrosine kinase is recruited to the TCR where it is activated by LCK through tyrosine phosphorylation. ZAP70 is a key signaling molecule in T cells, where it couples the antigen-activated TCR to downstream signaling pathways.28 Once ZAP70 has been activated, LCK and ZAP70 presumably act synergistically to phosphorylate specific downstream substrates, which in turn orchestrate the cytoplasmic signaling cascades leading to T-cell activation. These central roles of LCK and ZAP70 in TCR signaling have been amply documented. ZAP70 causes phosphorylation of LAT (linker for activation of T-cells), which in turn activates important downstream signaling pathways, ...
This chapter focuses on other modalities of signal transduction, including intracellular second messengers, feedback regulation, and posttranslational modifications such as the phosphorylation-dephosphorylation of proteins. Empirical studies of archaeal-archaeal and archaeal-bacterial communication have been few in number and preliminary in nature. Inspection of archaeal genomes has revealed them to be devoid of homologs of the prototypic bacterial quorum-sensing proteins LuxS and LuxR. Two-component systems differ in several fundamental respects from protein-serine/threonine/tyrosine phosphorylation cascades. First, autophosohorylation is the predominant mechanism of phosphorylation in the two-component system, whereas protein-serine/threonine/tyrosine phosphorylation cascades rely primarily on phosphotransfer reactions catalyzed by protein kinases that are distinct from the phosphoacceptor protein. Second, the chemical nature of the phosphoryl moieties formed during two-component signaling differs
Angiotensin II (ANG II) has been implicated in the pathogenesis of diabetic micro- and macrovascular disease. In vascular smooth muscle cells (VSMCs), ANG II phosphorylates and degrades insulin receptor substrate-1 (IRS-1). While the pathway responsible for IRS-1 degradation in this system is unknown, c-Jun NH2-terminal kinase (JNK) has been linked with serine phosphorylation of IRS-1 and insulin resistance. We investigated the role of JNK in ANG II-induced IRS-1 phosphorylation, degradation, Akt activation, glucose uptake, and hypertrophic signaling, focusing on three IRS-1 phosphorylation sites: Ser302, Ser307, and Ser632. Maximal IRS-1 phosphorylation on Ser632 occurred at 5 min, on Ser307 at 30 min, and on Ser302 at 60 min. The JNK inhibitor SP600125 reduced ANG II-induced IRS-1 Ser307 phosphorylation (by 80%), IRS-1 Ser302 phosphorylation (by 70%), and IRS-1 Ser632 phosphorylation (by 50%). However, JNK inhibition had no effect on ANG II-mediated IRS-1 degradation, nor did it reverse the ...
Angiotensin II (ANG II) has been implicated in the pathogenesis of diabetic micro- and macrovascular disease. In vascular smooth muscle cells (VSMCs), ANG II phosphorylates and degrades insulin receptor substrate-1 (IRS-1). While the pathway responsible for IRS-1 degradation in this system is unknown, c-Jun NH2-terminal kinase (JNK) has been linked with serine phosphorylation of IRS-1 and insulin resistance. We investigated the role of JNK in ANG II-induced IRS-1 phosphorylation, degradation, Akt activation, glucose uptake, and hypertrophic signaling, focusing on three IRS-1 phosphorylation sites: Ser302, Ser307, and Ser632. Maximal IRS-1 phosphorylation on Ser632 occurred at 5 min, on Ser307 at 30 min, and on Ser302 at 60 min. The JNK inhibitor SP600125 reduced ANG II-induced IRS-1 Ser307 phosphorylation (by 80%), IRS-1 Ser302 phosphorylation (by 70%), and IRS-1 Ser632 phosphorylation (by 50%). However, JNK inhibition had no effect on ANG II-mediated IRS-1 degradation, nor did it reverse the ...
Gang Zhang from the Nilsson group has been investigating the spindle assembly checkpoint in human cells and how it controls the timing of chromosome segregation. In particularly he has focused on understanding how the checkpoint protein Mad1 localized to kinetochores, large protein structures on chromosomes that bind to microtubules. It is known that Mad1 localization is important for checkpoint function but the underlying protein-protein interactions and their regulation have not been uncovered.. In collaboration with the Nielsen lab at CPR the researchers used an in vivo proximity dependent biotinylation approach coupled with mass spectrometry to identify Mad1 interactors. This revealed a so far elusive interaction with the Bub1 checkpoint protein that the researchers further characterized. Interestingly the binding of Mad1 and Bub1 required the phosphorylation of Bub1 by mitotic kinases and a novel generated phospho-specific antibody revealed that Bub1 was specifically phosphorylated on ...
Detection of phosphorylation by western blotting is an important procedure to elucidate molecular mechanisms in signal transduction pathways involving kinases and phosphatases. Anti-phospho-tyrosine monoclonal antibodies have been widely used because they react with plethora of proteins containing phosphorylated tyrosine residues. In contrast, the monoclonal antibodies against phospho-serine or threonine residues are unpopular, since their affinity and specificity are less than optimal. To achieve precise characterization of signaling events, it is desirable to raise a good anti-phospho-site-specific antibody to clearly detect phosphorylated species. However, raising this type of antibody is costly and time-consuming, and sometimes results in failure.. Use of Phos-tag may provide an alternative method to detect phosphorylated proteins. Phos-tag is a dinuclear metal complex that acts as a novel phosphate-binding tag. Phos-tag molecules preferentially capture phosphomonoester dianions bound to ...
Phosphorylation and de-phosphorylation play critical roles as a mode of signal transfer in biological processes. Check out our phosphorylation webpage to learn about this process, the proteins being phosphorylated, and the products offered at BioLegend to help you investigate this phenomenon. BioLegend develops and manufactures world-class, cutting-edge immunological reagents for biomedical research, offered at an outstanding value.
It has already been pointed out that a bivalent/multivalent TCR might improve the high off rate found for monovalent MHCp binding and can resolve the paradox of the high specificity-low affinity TCR-MHCp interaction (32). However, this does not readily explain how T cells manage to respond to a wide range of MHCp concentrations (6, 23-25). The coexistence of monovalent and multivalent TCRs may clarify this issue. Theoretical calculations suggest that cells coexpressing monovalent and multivalent forms of a given receptor can show high sensitivity to low concentrations of a ligand and concentration-dependent responses to high ligand concentrations (33). Indeed, by analyzing antigen-stimulated TCRs in BN-PAGE, we show that the multivalent TCR might facilitate signaling at low MHCp doses because only these complexes are phosphorylated at low peptide concentrations. On the other hand, the monovalent TCRs are only phosphorylated at high concentrations of peptide antigen, a situation in which the ...
PTMs (posttranslational modifications) such as ubiquitylation, sumoylation, acetylation and protein methylation are pivotal modifiers that determine the activation, deactivation or subcellular localization of signaling proteins, facilitating the initiation, amplification and transduction of signaling. Accumulating evidence suggest that several key signaling molecules in Hippo signaling pathway are tightly regulated by various types of PTMs. Malfunction of these critical signaling modules such as YAP/TAZ, MAT1/2 and LATS1/2 due to deregulated PTMs has been linked to a variety of human diseases such as cancer. In this review article, we summarized the current understanding of the impact of PTMs in regulating Hippo signaling pathway and further discussed the potential therapeutic intervention from the view of PTMs and Hippo pathway.
Concepts regarding the controls and consequences of PKD1-Ser738/Ser742 (activation loop) phosphorylation are based largely on early studies that used an anti-PKD1-Ser(P)738/Ser(P)742 PSSA (from Cell Signaling Technology, Danvers, MA) and showed that PMA increases PKD1 activation loop phosphorylation in many cell types via a mechanism that requires nPKC isoform activity (PKCδ, PKCε, PKCη, and/or PKCθ). In vitro kinase assays showing direct phosphorylation of the PKD1 activation loop by certain nPKC isoforms also have been published (Brändlin et al., 2002). However, there is recent evidence that the Cell Signaling Technology anti-PKD1-Ser(P)738/Ser(P)742 PSSA primarily recognizes PKD1 phosphorylation at Ser738 and that PKD1 phosphorylation at Ser742 can be tracked with a different PSSA (commercially available from Abcam Inc., Cambridge, MA). Experiments that use a combined approach with these two PSSAs expose differences in the controls and consequences of PKD1 phosphorylation at Ser738 and ...
In adaptive immune responses, T-cell receptor (TCR) signaling impacts multiple cellular processes and results in T-cell differentiation, proliferation, and cytokine production. Although individual protein-protein interactions and phosphorylation events have been studied extensively, we lack a systems-level understanding of how these components cooperate to control signaling dynamics, especially during the crucial first seconds of stimulation. Here, we used quantitative proteomics to characterize reshaping of the T-cell phosphoproteome in response to TCR/CD28 co-stimulation, and found that diverse dynamic patterns emerge within seconds. We detected phosphorylation dynamics as early as 5 s and observed widespread regulation of key TCR signaling proteins by 30 s. Development of a computational model pointed to the presence of novel regulatory mechanisms controlling phosphorylation of sites with central roles in TCR signaling. The model was used to generate predictions suggesting unexpected roles ...
The NF-κB/Rel transcription factors are present in the cytosol in an inactive state complexed with the inhibitory IκB proteins. Activation of IκBα occurs through both serine and tyrosine phosphorylation events. Activation through phosphorylation at Ser-32 and Ser-36 is followed by proteasome-mediated degradation, resul
In article ,36cp86$3vu at agate.berkeley.edu, lhom at OCF.Berkeley.EDU (Louis Hom) writes: ,,I know antibodies are glycosylated, but are they phosphorylated? ,,-- ,Yes they are. I found that you the hard way while doing in vitro ,phosphorylation experiments :-( , ,Annette ,ah690549 at mbcr.bcm.tmc.edu I do not think they are normally phophorylated. But during in vitro phosphorylation experiments basically every protein around that has serine, threonine or tyrosine gets phosphorylated. So much for kinase specificity. Its obvious that in non physiological conditions (ie. kinase assay on IPs) the specificity goes down the drain ---------------------------------------------------------------------- Michele Fuortes, MD/PhD Dept. Cell Biology and Anatomy Cornell University Medical College 1300 York Ave - Box 57 New York, NY 10021 E-mail: mfuortes at med.cornell.edu ...
Last updated: May 12, 2010. Introduction:. Protein phosphorylation is the most ubiquitous post-translational modification (PTM), and plays important roles in most of biological processes. Identification of site-specific phosphorylated substrates is fundamental for understanding the molecular mechanisms of phosphorylation. Besides experimental approaches, prediction of potential candidates with computational methods has also attracted great attention for its convenience and fast-speed. In this review, we present a comprehensive but brief summarization of computational resources of protein phosphorylation, including phosphorylation databases, prediction of non-specific or organism-specific phosphorylation sites, prediction of kinase-specific phosphorylation sites or phospho-binding motifs, and other tools. A testing data set prepared from Phospho.ELM 6.0 is available at: Comparison_data. We apologized that the computational studies without any web links of databases or tools will not be included ...
Generation of Phospho-Ser65 Parkin and Phospho-Thr257 PINK1 Pre-clinical Monoclonal Antibodies and Characterization of Total PINK1 Pre-clinical Monoclonal ...
Phosphoinositide 3-Kinase (PI3K) is a central enzyme in a signaling pathway that mediates cellular responses to growth factors. This enzyme phosphorylates the 3 position of phosphatidylinositol-4,5-bisphosphate to produce phosphatidylinositol-3,4,5-trisphosphate (PIP3) at the plasma membrane. A number of signaling proteins, including the Ser/Thr protein kinases, AKT and PDK1, contain pleckstrin homology domains that bind specifically to PIP3. Thus, the generation of PIP3 at the plasma membrane in response to activation of PI3K by growth factors results in the initiation of downstream Ser/Thr phosphorylation cascades that control a variety of cellular responses. The signaling pathway downstream of PI3K is highly conserved from worms and flies to humans and genetic analysis of the pathway has revealed a conserved role in regulating glucose metabolism and cell growth. Based on deletion of genes encoding the catalytic or regulatory subunits of PI3K in the mouse, PI3K mediates insulin dependent ...
The large number of protein consensus sequences that may be recognized without computer analysis are reviewed. These include the extensive range of known phosphorylation site motifs for protein kinase
The chapters have been organized into 5 different sections, based on the similarity of protein phosphorylation pathways. The first section has 4 chapters summarizing on the role of Akt, mTOR and AMPK in cancer and metabolic disorders. The section focuses on the structure, function and regulation of mTOR1 and mTOR2 and their role in cancer, neurodegeneration, and diabetes, the role of Sestrins, a family of stressresponsive genes in regulating AMPK-mTOR pathway and their role in cardiovascular diseases, muscle- and neuro- degeneration, diabetes and cancer, the signaling pathways that regulate autophagy, including Akt, AMPK and mTOR, and the role of Akt/AMPK and PI3K/Erk pathways in fatty acids-stimulated glucose uptake. The second section has 4 chapters reviewing the role of protein phosphorylation in transcription, pre-mRNA splicing and DNA damage. The section emphasizes the regulation of RNA polymerase II sequentially by protein kinases and phosphatases in gene expression and therapeutically ...
Takaoka et al. have presented persuasive evidence that in MEFs the IFN-γ response is substantially augmented through autocrine IFN-α/β and that cross-recruitment and phosphorylation of the IFNAR1 subunit of the IFN-α/β receptor occurs in response to IFN-γ in these cells (24). We have been unable to obtain evidence for or against recruitment or phosphorylation of IFNAR1 in response to IFN-γ in the HT1080-based human cell systems used here (H. Isharc and I. M. Kerr, unpublished data). In a potentially analogous but inverse situation, cross-phosphorylation of the IFNGR1 subunit of the IFN-γ receptor in response to activation of erythropoietin/gp130 receptor chimeras in HT1080-based cell lines is observed. Importantly, however, such receptor cross-phosphorylation plays no part in the IFN-γ-like response observed (23), a result which emphasizes that even if IFNAR1 were recruited and phosphorylated in response to IFN-γ, proof of necessity of this for the IFN-γ antiviral response would ...
A-Kinase (cAMP dPK). A-Kinase (cAMP dPK),. Cyclic AMP dependent protein kinase. A family of enzymes activated by cyclic AMP, which catalyse intracellular phosphorylation reactions.. Protein scaffold complexes are a key mechanism by which a common signaling pathway can serve many different functions. Sequestering a signaling enzyme to a specific subcellular environment not only ensures that the enzyme is near its relevant targets, but also segregates this activity to prevent indiscriminate phosphorylation of other substrates. One family of diverse, well-studied scaffolding proteins are the A-kinase anchoring proteins (AKAPs). These anchoring proteins form multi-protein complexes that integrate cAMP signaling with other pathways and signaling events.. ...
BioAssay record AID 1078274 submitted by ChEMBL: Inhibition of human full length PKC zeta expressed in baculovirus assessed as substrate phosphorylation using fluorescence-labelled peptides as substrate at 0.2 uM after 90 mins by microfluidic peptide phosphorylation assay.
BioAssay record AID 1079124 submitted by ChEMBL: Inhibition of human full length PKC beta2 expressed in baculovirus assessed as substrate phosphorylation using fluorescence-labelled peptides as substrate at 420 uM after 90 mins by microfluidic peptide phosphorylation assay.
Predicted two-dimensional H2AX phosphorylation patterns with and without the 3D spreading mechanism.Example of XY projections of hit domains only (A) and of all
This is a different type of regulation from the more rapid (de)phosphorylation mechanism, but is by no means unusual in metabolic systems. The actual mechanism of this insulin-initiated regulation is beyond the scope of this course. However, recall that glucokinase is the "high Km" kinase for glucose, so there is really no reason for it to even be around if glucose concentrations stay low most of the time. ...
... : Main EGFR signaling pathways in wound healing and cancer. EGFR occupation by EGF or other cognate agonistic ligand triggers a conformational change within the receptor s topography leading to carboxy-terminal tyrosines phosphorylation and accessory proteins recruitment. Three major signaling pathways have been described upon EGFR occupation. PI3K, phosphatidil inositol 3-kinase, involved in cyto-protection and cell tolerance to hypoxia. PI3K phosphorylates downstream substrates as Akt or PKB on serine 473. Consequently Akt inhibits apoptosis via BAD and BAX inactivation. This pathway assists in cell survival and appears to be involved in wound bed and tumor cells survival when angiogenesis is not accomplished, thus contributing to tumor metastasis. Cell proliferation involves the RAS-RAF-MAPK pathway, where phosphorylated EGFR recruits accessory proteins which activate the oncogene derived proteins RAS, subsequently RAF, and the Mitogen-Activated Protein Kinase (MAPK) pathway leading ...
Activation of protein kinase clients by the Hsp90 system is mediated by the cochaperone protein Cdc37. Cdc37 requires phosphorylation at Ser13, but little is known about the regulation of this essential posttranslational modification. We show that Ser13 of uncomplexed Cdc37 is phosphorylated in vivo, as well as in binary complex with a kinase (C-K), or in ternary complex with Hsp90 and kinase (H-C-K). Whereas pSer13-Cdc37 in the H-C-K complex is resistant to nonspecific phosphatases, it is efficiently dephosphorylated by the chaperone-targeted protein phosphatase 5 (PP5/Ppt1), which does not affect isolated Cdc37. We show that Cdc37 and PP5/Ppt1 associate in Hsp90 complexes in yeast and in human tumor cells, and that PP5/Ppt1 regulates phosphorylation of Ser13-Cdc37 in vivo, directly affecting activation of protein kinase clients by Hsp90-Cdc37. These data reveal a cyclic regulatory mechanism for Cdc37, in which its constitutive phosphorylation is reversed by targeted dephosphorylation in Hsp90 ...
Adenosine triphosphate, labeled on the gamma phosphate group with 35S (ATP?S), is used in protein kinase assays (thiosphosphorylation) in place of ATP. It can be used as a substrate for many protein kinases. One of the advantages of this substrate and its phosphorylated products is that they are hydrolyzed slowly by phosphatases and ATPases, and are therefore more metabolically stable.. ...
This protein phosphorylation antibody pair set comes with two antibodies, one against the TP53 protein, and the other against the specific S9 phosphorylated site of TP53 for use in in situ Proximity Ligation Assay. See Publication Reference below. (DP0014) - Products - Abnova
This protein phosphorylation antibody pair set comes with two antibodies, one against the TP53 protein, and the other against the specific S20 phosphorylated site of TP53 for use in in situ Proximity Ligation Assay. See Publication Reference below. (DP0087) - Products - Abnova
In eukaryotic cells many diverse cellular functions are regulated by reversible protein phosphorylation. In recent years, phosphoproteomics has become a powerful tool for studying protein...
It kind of depends on what all is known so far and some of it is just going to be trying and seeing what works. If you know the kinase that phosphorylates the protein you can do in vitro and/or in cyto phosphorylation and seeing if it is activated. If you know the site that is likely phosphorylated you can mutate the residue(s) to alanine(s), which cannot be phosphorylated. You can also do the reverse and mutate the residue(s) to aspartic acid, which have a negative charge and can sometimes mimic the phosphorylated state. It just depends on what you know, what you need to know, and what you have available to you.. ...
Function: Positive effector of BCR-stimulated responses. Couples the B-cell antigen receptor (BCR) to the mobilization of calcium ion either through a phosphoinositide 3-kinase-dependent pathway, when not phosphorylated on tyrosines of the linker region, or through a phospholipase C-gamma-dependent pathway, when phosphorylated on Tyr-348 and Tyr-352. Thus the differential phosphorylation of Syk can determine the pathway by which BCR is coupled to the regulation of intracellular calcium ion (By similarity ...
In our previous work, we showed by in vitro ARE-specific decay assays that BRF1 activity was regulated at Ser92 by PKB. However, the in vivo experiments reported here reveal that the mechanism is more complex in intact cells in that the PKB-dependent regulation of BRF1 activity could not be evaded by a Ser92 mutation (Fig. 1B), calling for the existence of at least one additional PKB regulatory site on BRF1. This is in keeping with the fact that the Ser92-based mechanism involves binding to 14-3-3, which usually binds to its target proteins at two separate locations (1, 49). We focused on Ser203 as a candidate for the additional phosphoregulatory site because of its homology to TTP Ser178, which serves as one of two 14-3-3 binding sites (21). Although TTP Ser178 is phosphorylated by MK2 (21, 42), we found no evidence that BRF1 Ser203 is phosphorylated in vitro by this kinase or by p38 or ERK1. Instead, the site is strongly phosphorylated by PKB (Fig. 2). Taken together with the in vivo data, ...
reacts with Akt when phosphorylated at Ser473; also reacts with Akt2 and Akt3 when phosphorylated at corresponding residues. Does not recognize Akt phosphorylated at other sites, nor does it recognize phosphorylated forms of related kinases such as PKC or p70 S6 ...
STAT-6 is a central mediator of IL-4-induced gene responses. It has been shown that STAT-6 is expressed in B cells and T cells upon stimulation with IL-4. Interleukin-12 (IL-12) and IL-18 are the key factors for the induction of Th1 Cells, early signals being involved in Th2 differentiation if any by IL-18 are less well characterized. We have investigatedthe mechanisms employed by IL-18 and IL-4 to control expression of STATs. Since we have shown in earlier studies that Th2 cytokines protect cells from apoptosis, we explored the possible role of the controversial cytokine IL-18 on Th2 shift and analyzed the effects of IL-18 on CD4+ T cells. Cells were cultured either with IL-18, IL-4, IL-18 + CD28 for different time points. The optimum time required for the phosphorylation of STAT-6 when stimulated with IL-18 was 72 hours. This effect of STAT-6 phosphorylation was blocked by addition of anti-IL-18 antibody in the culture. However, phosphorylation of STAT-1 and STAT-4 was seen by 24 hours. ...
Creative Bioarray offers a wide range of cell line testing and assays from cell viability and proliferation to cellular phosphorylation assays.
Protein phosphorylation significantly impacts protein function. Find products, protocols, articles and pathways for protein phosphorylation research.
Mouse Monoclonal Anti-Phospho-Tyrosine Antibody (G104) [DyLight 350]. Validated: WB, ICC/IF, IHC, IHC-P. Tested Reactivity: Non-species specific. 100% Guaranteed.
Acts as an adapter for the receptor ERBB2, in epithelia. By binding the unphosphorylated ERBB2 Tyr-1248 receptor, it may contribute to stabilize this unphosphorylated state (By similarity). Inhibits NOD2-dependent NF-kappa-B signaling and proinflammatory cytokine secretion (PubMed:16203728).
We are interested in how various bacteria (e.g., the model Gram+ spore-former B. subtilis and S. aureus) enter in dormancy and also re-initiate growth. We have identified several well-conserved, eukaryotic-like Ser/Thr kinase that are essential for these processes and are investigating the mechanism underlying their function. Among their targets are two essential GTPases, EF-Tu and EF-G, that are key in regulating protein synthesis. Specifically, we are examining how this phosphorylation changes the activity of these protein. In addition, we are examining the role of this kinase in antibiotic resistance and survival during stationary phase ...
Phosphatidylinositol (PtdIns) and its phosphorylated derivatives represent less than 5% of total membrane phospholipids in cells. Despite their low abundance, they form a dynamic signalling system that is regulated in response to a variety of extra and (...). ...
Mertins P, et al. (2014) Ischemia in tumors induces early and sustained phosphorylation changes in stress kinase pathways but does not affect global protein levels. Mol Cell Proteomics 13, 1690-704 ...
Loss of eif-2alpha phosphorylation on S49 (mammalian S51) associated with the integrated stress response hastens development in C. elegans ...
How is Phosphorylated 112 kDa Protein abbreviated? p112 stands for Phosphorylated 112 kDa Protein. p112 is defined as Phosphorylated 112 kDa Protein very rarely.
ProSci offers more than 700 cell lysates that have been rigorously tested for your research projects. Order your research lysates online from ProSci today.
ProSci offers more than 700 cell lysates that have been rigorously tested for your research projects. Order your research lysates online from ProSci today.
This overview provides a history of protein phosphorylation research and provides the reader with an understanding of how and why labeling studies are performed
Gentaur molecular products has all kinds of products like :search , Gene Link \ Not I non_phosphorylated linker \ 26-3200-14 for more molecular products just contact us
neurofilament-associated kinase: phosphorylates a subset of peptides in vitro which are phosphorylated in vivo in cultured neurons
... analysis of phosphorylated proteins allows researchers a quick and effective way to measure signalling cascades in individual cells.
Activation induced cytidine deaminase (AID) is required for somatic hypermutation (SHM) and class-switch recombination (CSR). AID initiates the processes that carry out immunoglobulin diversity by deaminating cytosine residues within variable (V) and switch (S) regions on the Ig locus during active transcription. The resulting G:U mispairs can then be replicated or repaired by cellular repair mechanisms to give rise to isotype-switched and antigen-specific mature antibodies.; In this study I have identified two novel phosphorylation sites, serine 41 and serine 43, and demonstrated their importance in AID activity as well as confirmed the importance of serine 38 phosphorylation. Phosphorylation null mutants generated by replacing serine with alanine are much less active than wild-type AID, as is non-phosphorylated AID purified from E. coli. In contrast, phosphorylation charge mimic mutants generated by replacing serine with aspartic acid, are (3-4) fold more active than wild-type AID. ...
Activation induced cytidine deaminase (AID) is required for somatic hypermutation (SHM) and class-switch recombination (CSR). AID initiates the processes that carry out immunoglobulin diversity by deaminating cytosine residues within variable (V) and switch (S) regions on the Ig locus during active transcription. The resulting G:U mispairs can then be replicated or repaired by cellular repair mechanisms to give rise to isotype-switched and antigen-specific mature antibodies.; In this study I have identified two novel phosphorylation sites, serine 41 and serine 43, and demonstrated their importance in AID activity as well as confirmed the importance of serine 38 phosphorylation. Phosphorylation null mutants generated by replacing serine with alanine are much less active than wild-type AID, as is non-phosphorylated AID purified from E. coli. In contrast, phosphorylation charge mimic mutants generated by replacing serine with aspartic acid, are (3-4) fold more active than wild-type AID. ...
PFOS induces Sertoli cell injury using testicular cells isolated from rodent testes, but it remains unknown if PFOS has similar effects in humans. Herein, we maintained human Sertoli cells in a mitotically active state in vitro, thus enabling transfection experiments that altered gene expression to explore the molecular mechanism(s) underlying toxicant-induced cell injury. Human Sertoli cells obtained from men at ages 15, 23, 36 and 40 were cultured in vitro. These differentiated Sertoli cells remained mitotically active when cultured in the presence of 10% FBS (fetal bovine serum), with a replication time of ~1-3 weeks. At ~80% confluency, they were used for studies including toxicant exposure, immunoblotting, immunofluorescence analysis, tight junction (TJ)-permeability assessment, and overexpression of BTB (blood-testis barrier) regulatory genes such as FAK and its phosphomimetic mutants. PFOS was found to induce Sertoli cell injury through disruptive effects on actin microfilaments and ...
TY - JOUR. T1 - c-Src enhances the spreading of src-/-fibroblasts on fibronectin by a kinase-independent mechanism. AU - Kaplan, Kenneth B.. AU - Swedlow, Jason R.. AU - Morgan, David O.. AU - Varmus, Harold E.. PY - 1995/6/15. Y1 - 1995/6/15. N2 - We have explored the role of the tyrosine kinase c-Src in cellular adhesion. Fibroblasts derived from src-/-mice (src-/-fibroblasts) exhibit a reduced rate of spreading on fibronectin. This defect is rescued by expression of wild-type chicken c-Src. Analyses of mutants suggest that c-Src increases the rate of cell spreading in src-/- fibroblasts through a kinase-independent mechanism requiring both the SH3 and SH2 domains. To further address the role of c-Src in adhesion, we examined the activity and subcellular distribution of c-Src during the adhesion of fibroblasts on fibronectin. We observed a transient increase in the specific kinase activity of c-Src accompanied by the partial dephosphorylation of the negative regulatory site Y527. Activation of ...
Tyrosine phosphorylation of paxillin by the focal adhesion kinase (FAK) has been implicated as a signal transduction mechanism associated with cell adhesion and cytoskeletal reorganization. The potential role of serine phosphorylation of paxillin in these events has not been well characterized. In this study we have examined the phosphorylation profile of paxillin both invitro and invivo. By using glutathione S-transferase-paxillin fusion proteins in precipitation-kinase assays invitro we observed that a fusion protein spanning amino acid residues 54-313 of paxillin, and containing a FAK-binding site, precipitated substantial serine kinase activity as well as FAK activity from a smooth-muscle lysate. Together these kinases phosphorylated paxillin on tyrosine residue 118, a site that has been identified previously as a target for FAK phosphorylation, and on serine residues 188 and/or 190. The binding site for the serine kinase, the identity of which is currently unknown, was further mapped to ...
BA-Stk1 is a serine/threonine kinase (STK) expressed by Bacillus anthracis. In previous studies, we found that BA-Stk1 activity is modulated through dephosphorylation by a partner phosphatase, BA-Stp1. In this study, we identified critical phosphorylation regions of BA-Stk1 and determined the contributions of these phosphodomains to autophosphorylation and substrate phosphorylation. The data indicate that BA-Stk1 undergoes trans-autophosphorylation within a regulatory domain, referred to as the activation loop, which carries eight putative regulatory serine and threonine residues. We identified activation loop mutants that impacted kinase activity in three different manners: regulation of autophosphorylation (T162), regulation of substrate phosphorylation (T159 and S169), and regulation of overall kinase activity (T163). Tandem mass spectrometry (MS/MS) analysis of the phosphorylation profile of each mutant revealed a second site of phosphorylation on the kinase that was influenced by the
It has been observed that coincident with or immediately following IκBα degradation, p65 is phosphorylated at multiple residues, and these phosphorylation events are necessary for proper regulation of NF-κB function (45). The phosphorylation patterns of NF-κB proteins have not been characterized in T cell anergy, and so we asked whether aberrant phosphorylation was responsible for the defects in NF-κB function in anergic cells. An early step involves phosphorylation of p65 at Ser536 by the IKK complex (32-35), and it has been suggested that phosphorylation at this residue negatively regulates the kinetics of p65 nuclear translocation (33). We found that p65 is phosphorylated at Ser536 equivalently in both naive and anergic cells, which is consistent with our finding that p65 translocates to the nucleus with normal kinetics in anergic T cells. A second posttranslational modification important for NF-κB activity is phosphorylation at Ser276. We found that, as with Ser536 phosphorylation, p65 ...
PURPOSE: To study in both in situ and primary cultures the posttranslational phosphorylation of connexin46 (Cx46), one of two members of the connexin family of gap junction proteins expressed by lens fibers. METHODS: Phosphatase digestion, gel electrophoresis, cell culture, organ culture, immunoprecipitation, metabolic labeling, and phosphoamino acid analysis were the methods used in this study. RESULTS: Cx46 immunoprecipitated from either rat or bovine lenses resulted in a shift to a more rapidly migrating species. During rat embryonic development, the more rapidly migrating, nonphosphorylated form of Cx46 was prevalent at 15 days gestation; as development progressed, there was a loss of the nonphosphorylated form with a concomitant increase in the phosphorylated form, such that by 28 days after birth only the phosphorylated form was detectable. The rate of posttranslational phosphorylation was very slow compared to previously measured rates for connexin43. Primary cultures of rat embryonic ...
Greiser and colleagues (10) also report that, consistent with previous studies, the remaining RyR2 clusters were hyperphosphorylated at the protein kinase A (PKA) phosphorylation site (Ser2808), which may compensate for the reduction in RyR2 protein expression and help sustain subsarcolemmal Ca2+ release despite reduced L-type Ca2+ currents (Figure 1B). However, RAP myocytes exhibited reduced RyR2 phosphorylation at the calmodulin-dependent protein kinase II (CaMKII) phosphorylation site (Ser2815) and no changes in CaMKII activity. This finding contrasts with previous studies that reported increased atrial CaMKII activity and CaMKII-dependent RyR2-Ser2815 phosphorylation in human AF (5). Moreover, other studies have shown that treatment with CaMKII inhibitors or selective disruption of the Ser2815 CaMKII phosphorylation site prevented AF in animal models through a reduction of SR Ca2+ leak (12). One explanation for this discrepancy could be the limited duration of pacing in the rabbit model used ...
The results of the present study identify the ERK 1/2 MAP kinase as being responsible for phosphorylation of eNOS at Ser116 in endothelial cells under basal conditions. Ser116 phosphorylation has been shown previously by Kou et al to be reduced by the protein kinase C (PKC) inhibitor calphostin C, implicating PKC as a mediator of this specific phosphorylation reaction.21 However, Shaw and colleagues22,23 have recently shown that the AGC kinases (protein kinase A, protein kinase G, and PKC), as well as the calmodulin-dependent protein kinases, cannot phosphorylate serines or threonines in protein substrates containing a proline at the P+1 position. Proline at P+1 is thus a "veto residue" that precludes phosphorylation by AGC and calmodulin-dependent protein kinases. This feature of proline-directed phosphorylation provides very tight control in preventing reciprocal substrate specificity between proline-directed protein kinases and AGC/calmodulin-dependent protein kinases. Because Ser116 in the ...
The large extracellular domain of glycoprotein hormone receptors is a unique feature within the G protein-coupled receptors (GPCRs) family. After interaction with the hormone, the receptor becomes coupled to Gs, which, in turn stimulates adenylyl cyclase and the production of cAMP. Potential phospho …
CHOP, a member of the C/EBP family of transcription factors, mediates effects of cellular stress on growth and differentiation. It accumulates under conditions of stress and undergoes inducible phosphorylation on two adjacent serine residues (78 and 81). In vitro, CHOP is phosphorylated on these residues by p38 mitogen-activated protein kinase (MAP kinase). A specific inhibitor of p38 MAP kinase, SB203580, abolished the stress-inducible in vivo phosphorylation of CHOP. Phosphorylation of CHOP on these residues enhanced its ability to function as a transcriptional activator and was also required for the full inhibitory effect of CHOP on adipose cell differentiation. CHOP thus serves as a link between a specific stress-activated protein kinase, p38, and cellular growth and differentiation. ...
TY - JOUR. T1 - Different phosphorylated forms of myosin in contracting tracheal smooth muscle. AU - Persechini, A.. AU - Kamm, K. E.. AU - Stull, J. T.. PY - 1986. Y1 - 1986. N2 - Calmodulin-dependent myosin light chain kinase phosphorylates two light chain subunits on each myosin molecule. We have developed a method for measuring nonphosphorylated, monophosphorylated, and diphosphorylated forms of myosin in smooth muscle. Four protein bands were separated in tissue extracts by nondenaturing polyacrylamide gel electrophoresis in the presence of pyrophosphate. Immunoblots demonstrated that three forms (designated M, MP, and MP2) reacted with rabbit antisera prepared against the purified phosphorylated light chain (P-light chain) from bovine tracheal smooth muscle. Evidence was obtained that M, MP, and MP2 represented nonphosphorylated, monophosphorylated, and diphosphorylated myosin, respectively, and that the other protein band was probably filamin. The formation of different phosphorylated ...
TY - JOUR. T1 - A role for protein kinase C-mediated phosphorylation in eliciting glucagon desensitization in rat hepatocytes. AU - Savage, A.. AU - Zeng, L.. AU - Houslay, M. D.. PY - 1995/4/1. Y1 - 1995/4/1. N2 - An immobilized hepatocyte preparation was used to show that both vasopressin and glucagon could desensitize the ability of glucagon to increase intracellular cyclic AMP concentrations. This process was not dependent on any influx of extracellular Ca2+ and was not mediated by any rise in the intracellular level of Ca2+. The protein kinase C-selective inhibitors chelerythrine, staurosporine and calphostin C acted as potent inhibitors of the desensitization process but with various degrees of selectivity regarding their ability to inhibit the desensitizing actions of glucagon and vasopressin. The protein phosphatase inhibitor okadaic acid was just as potent as vasopressin and glucagon in causing desensitization. Treatment of hepatocyte membranes with alkaline phosphatase restored to near ...
TY - JOUR. T1 - Agonist dose-dependent phosphorylation by protein kinase A and G protein-coupled receptor kinase regulates β2 adrenoceptor coupling to Gi proteins in cardiomyocytes. AU - Liu, Ruijie. AU - Ramani, Biswarathan. AU - Soto, Dagoberto. AU - De Arcangelis, Vania. AU - Xiang, Yang Kevin. PY - 2009/11/20. Y1 - 2009/11/20. N2 - Adrenoceptors receptors (ARs) play a pivotal role in regulating cardiovascular response to catecholamines during β2ARs, prototypical G protein-coupled receptors (GPCRs), expressed in animal hearts, display dual coupling to both Gs and Gi proteins to control the adenylyl cyclase-cAMP dependent protein kinase A (PKA) pathway to regulate contraction responses. Here, we showed that β2AR coupling to Gi proteins was agonist dose-dependent and occurred only at high concentrations in mouse cardiac myocytes. Both β2AR-induced PKA activity, measured by fluorescence resonance energy transfer (FRET) imaging, and the increase in myocyte contraction rate displayed ...
The mitogen-activated protein kinase-activated protein kinase MK5 is a substrate of the mitogen-activated protein kinases p38, ERK3 and ERK4. Cell culture and animal studies have demonstrated that MK5 is involved in tumour suppression and promotion, embryogenesis, anxiety, cell motility and cell cycle regulation. In the present study, homology models of MK5 were used for molecular dynamics (MD) simulations of: (1) MK5 alone; (2) MK5 in complex with an inhibitor; and (3) MK5 in complex with the interaction partner p38α. The calculations showed that the inhibitor occupied the active site and disrupted the intramolecular network of amino acids. However, intramolecular interactions consistent with an inactive protein kinase fold were not formed. MD with p38α showed that not only the p38 docking region, but also amino acids in the activation segment, αH helix, P-loop, regulatory phosphorylation region and the C-terminal of MK5 may be involved in forming a very stable MK5-p38α complex, and that p38α
Increasing evidence supports the hypothesis that tannic acid, a plant polyphenol, exerts anticarcinogenic activity in chemically induced cancers. In the present study, tannic acid was found to strongly inhibit tyrosine kinase activity of epidermal growth factor receptor (EGFr) in vitro (IC50 = 323 nM). In contrast, the inhibition by tannic acid of p60c-src tyrosine kinase (IC50 = 14 μM) and insulin receptor tyrosine kinase (IC50 = 5 μM) was much weaker. The inhibition of EGFr tyrosine kinase by tannic acid was competitive with respect to ATP and non-competitive with respect to peptide substrate. In cultured cells, growth factor-induced tyrosine phosphorylation of growth factor receptors, including EGFr, platelet-derived growth factor receptor, and basic fibroblast growth factor receptor, was inhibited by tannic acid. No inhibition of insulin-induced tyrosine phosphorylation of insulin receptor and insulin-receptor substrate-1 was observed. EGF-stimulated growth of HepG2 cells was inhibited in ...
TY - JOUR. T1 - Biochemical basis for the functional switch that regulates hepatocyte growth factor receptor tyrosine kinase activation. AU - Sheth, Payal R.. AU - Hays, John L.. AU - Elferink, Lisa. AU - Watowich, Stanley. PY - 2008/4/1. Y1 - 2008/4/1. N2 - Ligand-induced dimerization of receptor tyrosine kinases (RTKs) modulates a system of linked biochemical reactions, sharply switching the RTK from a quiescent state to an active state that becomes phosphorylated and triggers intracellular signaling pathways. To improve our understanding of this molecular switch, we developed a quantitative model for hepatocyte growth factor receptor (c-MET) activation using parameters derived in large part from c-MET kinetic and thermodynamic experiments. Our model accurately produces the qualitative and quantitative dynamic features of c-MET phosphorylation observed in cells following ligand binding, including a rapid transient buildup of phosphorylated c-MET at high ligand concentrations. In addition, our ...
Looking for online definition of growth factor receptor-bound protein 7 in the Medical Dictionary? growth factor receptor-bound protein 7 explanation free. What is growth factor receptor-bound protein 7? Meaning of growth factor receptor-bound protein 7 medical term. What does growth factor receptor-bound protein 7 mean?
16S ribosomal RNA, 30S ribosomal protein S2, 30S ribosomal protein S3, 30S ribosomal protein S4, 30S ribosomal protein S5, 30S ribosomal protein S6, 30S ribosomal protein S7, 30S ribosomal protein S8, 30S ribosomal protein S9, 30S ribosomal protein S10, 30S ribosomal protein S11, 30S ribosomal protein S12, 30S ribosomal protein S13, 30S ribosomal protein S14, 30S ribosomal protein S15, 30S ribosomal protein S16, 30S ribosomal protein S17, 30S ribosomal protein S18, 30S ribosomal protein S19, 30S ribosomal protein S20, 30S ribosomal protein Thx, RNA (5-R(*AP*AP*AP*AP*AP*GP*GP*AP*AP*AP*UP*A*AP*AP*AP*AP*UP*GP*CP*AP*GP*UP*UP*CP*AP*AP*UP*CP*UP*A)-3), tRNA-Gln, tRNA-Met, tRNA-Gln, capreomycin IA, 50S ribosomal protein L27, 50S ribosomal protein L28, 50S ribosomal protein L29, 50S ribosomal protein L30, 50S ribosomal protein L31, 50S ribosomal protein L32, 50S ribosomal protein L33, 50S ribosomal protein L34, 50S ribosomal protein L35, 50S ribosomal protein L36, 23S ribosomal RNA, 5S ribosomal RNA, ...
Phosphorylation H2B at serine 10/14 (phospho-H2BS10/14). Phosphorylation of H2B at serine 10 (yeast) or serine 14 (mammals) is ... It is not clear what structural implications histone phosphorylation has, but histone phosphorylation has clear functions as a ... Phosphorylation of H2AX at serine 139 (γH2AX). Phosphorylated H2AX (also known as gamma H2AX) is a marker for DNA double strand ... Phosphorylation of H3 at serine 10 (phospho-H3S10). The mitotic kinase aurora B phosphorylates histone H3 at serine 10, ...
This potential energy is used for the synthesis of ATP by oxidative phosphorylation or photophosphorylation, respectively.[2] ... Utilizing one full oxygen in oxidative phosphorylation requires the transfer of four electrons. The oxygen will then consume ... Electrochemical gradients also play a role in establishing proton gradients in oxidative phosphorylation in mitochondria. The ... "Oxidative phosphorylation revisited". Biotechnology and Bioengineering. 112 (3): 429-437. doi:10.1002/bit.25492. ISSN 1097- ...
Oxidative phosphorylation[edit]. Main article: oxidative phosphorylation. Oxidative phosphorylation produces 26 of the 30 ... The biosynthesis of ATP is achieved throughout processes such as substrate-level phosphorylation, oxidative phosphorylation, ... "Oxidative phosphorylation". W H Freeman, 2002. Retrieved 4 April 2013.. *^ Medh, J. D. "Electron Transport Chain (Overview)" ( ... energy coupling and phosphorylation of ADP to ATP that gives the electron transport chain the name oxidative phosphorylation. ...
Phosphorylation occurs at two sites within the heptapeptide repeat, at Serine 5 and Serine 2. Serine 5 phosphorylation is ... Regulation by phosphorylation[edit]. The largest subunit of Pol II (Rpb1) has a domain at its C-terminus called the CTD (C- ... the pattern of phosphorylation on individual CTDs can vary due to differential phosphorylation of Ser2 versus Ser5 residues and ... CTD phosphorylation[edit]. RNAPII can exist in two forms: RNAPII0, with a highly phosphorylated CTD, and RNAPIIA, with a ...
Berg, Jeremy M.; Tymoczko, J. L.; Stryer, L. (2006). "Oxidative phosphorylation". Biochemistry (5 ed.). pp. 491-526. ISBN ...
Phosphorylation at four serine residues on stathmin named Ser16, Ser25, Ser38 and Ser63 causes weakened stathmin-tubulin ... Stathmin phosphorylation increases the concentration of tubulin available in the cytoplasm for microtubule assembly. For cells ... Its phosphorylation and gene expression are regulated throughout development and in response to extracellular signals ... Brattsand G, Marklund U, Nylander K, Roos G, Gullberg M (March 1994). "Cell-cycle-regulated phosphorylation of oncoprotein 18 ...
As a sidenote, AK-III catalyzes the phosphorylation of aspartic acid that is the committed step in this biosynthetic pathway. ... Homoserine undergoes O-phosphorylation; this phosphate ester undergoes hydrolysis concomitant with relocation of the OH group.[ ... The enzyme aspartokinase, which catalyzes the phosphorylation of aspartate and initiates its conversion into other amino acids ... Synthesis begins with phosphorylation of 5-phosphoribosyl-pyrophosphate (PRPP), catalyzed by ATP-phosphoribosyl transferase. ...
"Is Tau Phosphorylation All Bad? - ALZFORUM".. *^ Kril J. J.; Patel S.; Harding A. J.; Halliday G. M. (2002). "Neuron loss from ... 2005). "Tau phosphorylation in Alzheimer's disease: pathogen or protector?". Trends in Molecular Medicine. 11 (4): 164-169. doi ... Lithium has been shown to decrease the phosphorylation of tau.[19] Lithium treatment has been shown to reduce the density of ... Results from the new study [8] suggest that a specific phosphorylation of tau (at threonine-205) has a protective effect on ...
Phosphorylation of c-Myc oncoprotein". European Journal of Biochemistry / FEBS. 206 (2): 595-603. PMID 1597196. doi:10.1111/j. ... Seth A, Alvarez E, Gupta S, Davis RJ (December 1991). "A phosphorylation site located in the NH2-terminal domain of c-Myc ... Noguchi K, Kitanaka C, Yamana H, Kokubu A, Mochizuki T, Kuchino Y (November 1999). "Regulation of c-Myc through phosphorylation ... 1-butanone promotes functional cooperation of Bcl2 and c-Myc through phosphorylation in regulating cell survival and ...
This process is called phosphorylation. Protein phosphorylation in particular plays a significant role in a wide range of ... "A mitotic role for a novel fission yeast protein kinase dsk1 with cell cycle stage dependent phosphorylation and localization" ...
Oxidative phosphorylation. References[edit]. *^ Peter Mitchell (1961). "Coupling of phosphorylation to electron and hydrogen ... is also called phosphorylation potential. The equilibrium concentration ratio [. H. +. ]. /. [. A. T. P. ]. {\displaystyle [\ ... Chemiosmotic phosphorylation is the third pathway that produces ATP from inorganic phosphate and an ADP molecule. This process ... This process is called oxidative phosphorylation because it uses energy released by the oxidation of NADH and FADH2 to ...
Uncouplers of oxidative phosphorylation. „Meth. Enzymol.". 55, s. 462-42, 1979. DOI: 10.1016/0076-6879(79)55060-5. PMID: 156853 ... Slater EC.. Mechanism of Phosphorylation in the Respiratory Chain. „Nature". 172 (4387), s. 975, 1953. DOI: 10.1038/172975a0. ... Boyer PD, Cross RL, Momsen W. A new concept for energy coupling in oxidative phosphorylation based on a molecular explanation ... Schägger H, Pfeiffer K. The ratio of oxidative phosphorylation complexes I-V in bovine heart mitochondria and the composition ...
Ser/Thr phosphorylation sites in activation loops: *human PAK1, Thr423 (PDB: 3Q4Z, 4O0R, 4O0T, 4P90, 4ZLO, 4ZY4, 4ZY5, 4ZY6, ... It is generally defined as the phosphorylation of the kinase by itself. In eukaryotes, this process occurs by the addition of a ... N or C terminal tails Ser/Thr phosphorylation sites: *C. elegans CaMKII, C-terminal tail, Thr284 (PDB: 3KK8, 3KK9)[19] ... Tyr phosphorylation sites in kinase insert regions: *human FGFR1, Tyr583 (PDB: 3GQI)[9] ...
But phosphorylation at Ser19 increases the rate of phosphorylation at Ser40, leading to an increase in enzyme activity. ... and increases the enzyme activity to a lesser extent than for Ser40 phosphorylation.[28] The phosphorylation at Ser19 and Ser8 ... Phosphorylation at Ser19 causes a two-fold increase of activity, through a mechanism that requires the 14-3-3 proteins.[31] ... Increase in tyrosine hydroxylase activity due to phosphorylation can be sustained by nicotine for up to 48 hours.[7][38] ...
This enzyme participates in oxidative phosphorylation. It has four cofactors: cytochrome c1, cytochrome b-562, cytochrome b-566 ... oxidative phosphorylation). Complex III is a multisubunit transmembrane protein encoded by both the mitochondrial (cytochrome b ...
A cyclin forms a complex with Cdk, which begins to activate but the complete activation requires phosphorylation, as well. ... MPFs activate other proteins through phosphorylation. These phosphorylated proteins, in turn, are responsible for specific ...
Kalckar HM (November 1974). "Origins of the concept oxidative phosphorylation". Molecular and Cellular Biochemistry. 5 (1-2): ... such as phosphorylation, methylation, or glycosylation in that the amino acids typically acquire new functions. This increases ...
Phosphorylation. It consists of the addition of a phosphate group (HPO3). In EHD3, there are two serine phosphorylations; one ... Apart from an EF-hand domain, it can also include tyrosine phosphorylation sites and coiled coils. This domain is often related ...
Evidence for phosphorylation-dependent interactions». J. Biol. Chem. (United States) 277 (25): 23054-64. ISSN 0021-9258. PMID ... de 2002). «Direct identification of PTEN phosphorylation sites». FEBS Lett. (Netherlands) 528 (1-3): 145-53. ISSN 0014-5793. ... de 2004). «Phosphorylation of the regulatory beta-subunit of protein kinase CK2 by checkpoint kinase Chk1: identification of ... de 2000). «Tumor necrosis factor alpha-induced phosphorylation of RelA/p65 on Ser529 is controlled by casein kinase II». J. ...
Ratnikov B, Ptak C, Han J, Shabanowitz J, Hunt DF, Ginsberg MH (Nov 2005). "Talin phosphorylation sites mapped by mass ... which houses several sites of phosphorylation,[28] as well as protease cleavage.[29] Talin-1 can homodimerize in an ...
21] TFEB nuclear export is mediated by CRM1 and is dependent on phosphorylation.[22][23] TFEB is also a target of the protein ... Nuclear localization and activity of TFEB is inhibited by serine phosphorylation by mTORC1 and extracellular signal-regulated ... kinase 2 (ERK2). [8][17][18][19] mTORC1 phosphorylation of TFEB occurs at the lysosomal surface, both of which are localized ... "mTOR-dependent phosphorylation controls TFEB nuclear export". Nature Communications. 9 (1): 3312. Bibcode:2018NatCo...9.3312N ...
Phosphorylation of prolidase has been shown to increase its activity while dephosphorylation leads to a decrease in enzyme ... Additionally, prolidase may also be regulated at tyrosine phosphorylation sites, which are mediated by FAK and MAPK signaling ... Surazyński A, Pałka J, Wołczyński S (Apr 2001). "Phosphorylation of prolidase increases the enzyme activity". Molecular and ... Analysis of known consensus sequence required for serine/threonine phosphorylation revealed that prolidase contains at least ...
Role of receptor phosphorylation in signal attenuation". The Journal of Biological Chemistry. 270 (15): 8944-51. doi:10.1074/ ...
Furthermore, the second phosphorylation event is necessary to allow the formation of two charged groups (rather than only one) ... The phosphorylation and dephosphorylation of these enzymes (ultimately in response to the glucose level in the blood) is the ... A final substrate-level phosphorylation now forms a molecule of pyruvate and a molecule of ATP by means of the enzyme pyruvate ... This step, one of the two substrate-level phosphorylation steps, requires ADP; thus, when the cell has plenty of ATP (and ...
Berg, Jeremy M.; Tymoczko, J. L.; Stryer, L. (2006). "Oxidative phosphorylation". Biochemistry. 5: 491-526. Alberty, Robert A ...
A total of 13 likely phosphorylation sites were predicted: Ser: 5 Thr: 6 Tyr: 2 The main concentration of the phosphorylation ...
Insulin receptor phosphorylation may not be a prerequisite for acute insulin action. / Simpson, Ian A.; Hedo, José A. ... Insulin receptor phosphorylation may not be a prerequisite for acute insulin action. Science. 1984 Jan 1;223(4642):1301-1304. ... Simpson, Ian A. ; Hedo, José A. / Insulin receptor phosphorylation may not be a prerequisite for acute insulin action. In: ... Simpson, I. A., & Hedo, J. A. (1984). Insulin receptor phosphorylation may not be a prerequisite for acute insulin action. ...
What is the difference between Substrate Level Phosphorylation and Oxidative Phosphorylation? Substrate level phosphorylation ... Substrate Level Phosphorylation: Substrate phosphorylation is a direct phosphorylation.. Oxidative Phosphorylation: Oxidative ... Substrate Level Phosphorylation vs Oxidative Phosphorylation. Substrate level phosphorylation and oxidative phosphorylation are ... What is Oxidative Phosphorylation. Oxidative phosphorylation refers to a type of phosphorylation that uses the energy released ...
Vinculin and talin were in vitro substrates for phosphorylation by EC PKC, a key effector enzyme involved in thrombin-induced ... Vinculin and talin were in vitro substrates for phosphorylation by EC PKC, a key effector enzyme involved in thrombin-induced ... Vinculin and talin were in vitro substrates for phosphorylation by EC PKC, a key effector enzyme involved in thrombin-induced ... Vinculin and talin were in vitro substrates for phosphorylation by EC PKC, a key effector enzyme involved in thrombin-induced ...
Additionally, FLCN phosphorylation (on Serines 62 and 73) fluctuates throughout the cell cycle and peaks during the G2/M phase ... D. J. A. Wilson, "Human folliculin delays cell cycle progression through late S and G2/M-phases: effect of phosphorylation and ... Human folliculin delays cell cycle progression through late S and G2/M-phases: effect of phosphorylation and tumor associated ... "Human folliculin delays cell cycle progression through late S and G2/M-phases: effect of phosphorylation and tumor associated ...
Protein phosphorylation[edit]. Main article: Protein phosphorylation. Function[edit]. Reversible phosphorylation of proteins is ... Types of phosphorylation[edit]. Further information: Kinase. Within a protein, phosphorylation can occur on several amino acids ... Regulatory roles of phosphorylation include *Biological thermodynamics of energy-requiring reactions *Phosphorylation of Na+/K+ ... Phosphorylation on serine is thought to be the most common, followed by threonine. Tyrosine phosphorylation is relatively rare ...
Phosphorylation assays. PID‐GST autophosphorylation and PID‐dependent phosphorylation of myelin‐binding protein (MBP) was ... Note that absence of peptide 2 phosphorylation is probably due to inefficient PID phosphorylation of S634 at the very C‐ ... Endler A, Reiland S, Gerrits B, Schmidt UG, Baginsky S, Martinoia E (2009) In vivo phosphorylation sites of barley tonoplast ... Huang F, Zago MK, Abas L, van Marion A, Galvan‐Ampudia CS, Offringa R (2010) Phosphorylation of conserved PIN motifs directs ...
In living cells phosphorylation is associated with respiration , which takes place in the cells mitochondria, and ... phosphorylation. phosphorylation, chemical process in which a phosphate group is added to an organic molecule. In living cells ... The net result in phosphorylation of ADP is the formation of the high-energy molecule ATP, which the cell can use as a kind of ... Other phosphorylation reactions occur in cells, some without mediation by the electron transport chain, e.g., ATP is formed ...
Phosphorylation, in chemistry, the addition of a phosphoryl group (PO32-) to an organic compound. The process by which much of ... the energy in foods is conserved and made available to the cell is called oxidative phosphorylation (see cellular respiration ... Phosphorylation, in chemistry, the addition of a phosphoryl group (PO32-) to an organic compound. The process by which much of ... photosynthesis: Phosphorylation. The three molecules of Ru5P are converted to the carboxylation substrate, RuBP, by the enzyme ...
Serine phosphorylation of STATs.. Decker T1, Kovarik P.. Author information. 1. Vienna Biocenter, Institute of Microbiology and ... Tyrosine phosphorylation regulates the dimerization of STATs as an essential prerequisite for the establishment of a classical ... This review addresses recent advances in understanding the regulation of STAT serine phosphorylation, as well as the kinases ... However, most vertebrate STATs contain a second phosphorylation site within their C-termini. The phosphorylated residue in this ...
In oxidative phosphorylation the oxidation of catabolic intermediates by molecular oxygen occurs via a highly ordered series of ... phosphorylation. * In phosphorylation. …to the cell is called oxidative phosphorylation (see cellular respiration). The process ... In cellular respiration: Oxidative phosphorylation. In the oxidative phosphorylation stage, each pair of hydrogen atoms removed ... In metabolism: Oxidative, or respiratory-chain, phosphorylation. In oxidative phosphorylation the oxidation of catabolic ...
Synapsin, phosphorylation site (IPR019736). Short name: Synapsin_P_site Description. The synapsins are a family of neuron- ... protein kinase-mediated phosphorylation. This is followed by the `B linker domain, which is ~80 residues long and is ...
Protein phosphorylation is involved in many mechanisms that contribute to neuronal plasticity, i.e. in the modulation of the ... Haycock JW (1990) Phosphorylation of tyrosine hydroxylase in situ at serine 8, 19, 31, and 40. J Biol Chem 265: 11682-11691 ... Protein phosphorylation is involved in many mechanisms that contribute to neuronal plasticity, i.e. in the modulation of the ... Supattapone S, Danoff SK, Theibert A, Joseph SK, Steiner J, Snyder SH (1988) Cyclic AMP-dependent phosphorylation of a brain ...
... Siddhartha S Mitra ssmitra at acsu.buffalo.edu Mon Jun 12 21:24:40 EST 2000 *Previous ... but the best way to check for phosphorylation at a very low level I have found is if you are able to label with 32-P ATP ... I would like to determine whether my protein undergoes phosphorylation, , , preferably by using phospho serine and threonine ...
... Joel Baguet Joel.Baguet at ens-lyon.fr Wed Jan 7 06:20:41 EST 1998 *Previous message: Ustilago ... Does anybody have experience about the radio-labelling phosphorylation of this protein in the cellular extract? Is it the same ...
Positional Analysis of Phosphorylation Sites in Proteins.. Analysis of the position of phosphorylation sites along the protein ... Multiple Phosphorylations in a Short and Defined Distance: Double-Phosphorylation Motifs.. In this study, 39% of the ... Generation of a Large Phosphorylation Repertoire by MS.. The strategy used for large-scale phosphorylation analysis is shown in ... As an example from the double-phosphorylation motif, sPxxsP (37 matches), only the single-phosphorylation motif, SPxxsP, was ...
PubMed comprises more than 30 million citations for biomedical literature from MEDLINE, life science journals, and online books. Citations may include links to full-text content from PubMed Central and publisher web sites.
Modulation of the activity of proteins by phosphorylation has often been described as a binary switch, but Pufall et al. show ... Increasing phosphorylation progressively shifts the equilibrium toward the inhibited state and thus fine-tunes the level of ...
Protein phosphorylationEdit. Main article: Protein phosphorylation. Protein phosphorylation is considered the most abundant ... Phosphorylation of sugars is often the first stage in their catabolism. Phosphorylation allows cells to accumulate sugars ... While phosphorylation is performed by ATPs during preparatory steps, phosphorylation during payoff phase is maintained by ... Phosphorylation initiates the reaction in step 1 of the preparatory step[11] (first half of glycolysis), and initiates step 6 ...
A brief review is given of the history of the experimental demonstration of oxidative phosphorylation. The properties of the ... W.N. Aldridge, "Oxidative phosphorylation", Arhiv za higijenu rada i toksikologiju, vol.11, br. 1, str. 61-73, 1960. [Online]. ... Aldridge, W.N. (1960). Oxidative phosphorylation, Arhiv za higijenu rada i toksikologiju, 11(1), str. 61-73. Preuzeto s: ... Oxidative phosphorylation. Arh Hig Rada Toksikol. [Internet]. 1960 [pristupljeno 18.07.2019.];11(1):61-73. Dostupno na: https ...
Gentry, L. E., Chaffin, K. E., Shoyab, M. and Purchio, A. F., 1986, Novel serine phosphorylation of pp 60src in intact cells ... Shih T.Y., Saikumar P., Clanton D.J., Ulsh L.S. (1989) Novel Phosphorylation of ras p21 and Mutational Studies. In: Spandidos D ... Hunter, T., Ling, N. and Cooper, J. A., 1984, Protein kinase C phosphorylation of EGF receptor at a threonine residue close to ... Ballester, R., Furth M. E. and Rosen, O. M., 1987, Phorbol ester and protein kinase C-mediated phosphorylation of the cellular ...
This free synopsis covers all the crucial plot points of Oxidative Phosphorylation and Electron Transport. ... Home → SparkNotes → Biology Study Guides → Oxidative Phosphorylation and Electron Transport → Introduction. Oxidative ... Oxidative phosphorylation marks the final stage of aerobic cell respiration. We have traced metabolism from food to glucose, ... The energy produced from the flow of electrons drives oxidative phosphorylation in which ATP is synthesized via the addition of ...
Some of tau functions could be regulated by phosphorylation. In many cases, tau phosphorylation can cause its detachment from ... tau phosphorylation also takes place in those neurons, at sites recognized by AT8 antibody, phosphorylation which is fully ... Tau Phosphorylation by GSK3 in Different Conditions. Jesús Avila,1,2 Gonzalo León-Espinosa,2,3,4 Esther García,1,2 Vega García- ... U. Wagner, M. Utton, J. M. Gallo, and C. C. J. Miller, "Cellular phosphorylation of tau by GSK-3β influences tau binding to ...
Home → SparkNotes → Biology Study Guides → Oxidative Phosphorylation and Electron Transport → Problems. Oxidative ... the inner mitochondrial membrane enter the matrix space to participate in the citric acid cycle and oxidative phosphorylation? ...
Oxidative phosphorylation is the process of generating adenosine triphosphate, the main energy... ... Oxidative phosphorylation takes place in and around the membranes of mitochondria in eukaryotic cells. ... Oxidative phosphorylation takes place in and around the membranes of mitochondria in eukaryotic cells. Oxidative ... Oxidative phosphorylation is the main method whereby eukaryotic cells produce ATP aerobically. The step before oxidative ...
In Gram-positive bacteria, arginine phosphorylation by the McsB kinase functions as a general post-translational marker for Clp ... Here, Tim Clausen and colleagues report that arginine phosphorylation by the McsB kinase functions as a general post- ... In vitro reconstitution experiments demonstrate that arginine phosphorylation by the McsB kinase is required and sufficient for ... Arginine phosphorylation marks proteins for degradation by a Clp protease. *Débora Broch Trentini1. na1, ...
  • An antiserum to the insulin receptor mimicked insulin's acute actions on glucose transport, phosphorylation of integral membrane proteins, and internalization of the insulin receptor in isolated rat adipose cells. (elsevier.com)
  • Although vinculin and talin were phosphorylated in situ under basal conditions in 32 P-labeled EC, thrombin failed to alter the basal level of phosphorylation of these proteins. (elsevier.com)
  • These data indicate that modulation of cell tethering via phosphorylation of focal adhesion proteins is complex, agonist-specific, and may be a relevant mechanism of EC barrier dysfunction in permeability models that do not depend on an increase in myosin 20-kD regulatory light chain phosphorylation. (elsevier.com)
  • Vinculin and talin were in vitro substrates for phosphorylation by EC PKC, a key effector enzyme involved in thrombin-induced EC barrier dysfunction. (elsevier.com)
  • These findings suggest that the tumor suppression function of FLCN may be linked to its impact on the cell cycle and that FLCN phosphorylation is important for this activity. (unizg.hr)
  • Additionally, FLCN phosphorylation (on Serines 62 and 73) fluctuates throughout the cell cycle and peaks during the G2/M phase in cells treated with nocodazole. (unizg.hr)
  • The phosphorylation process is linked to cell metabolism in that metabolic degradation of food, e.g., glucose, allows formation of the coenzyme NADH. (infoplease.com)
  • In the oxidative phosphorylation stage, each pair of hydrogen atoms removed from NADH and FADH 2 provides a pair of electrons that-through the action of a series of iron-containing hemoproteins, the cytochromes-eventually reduces one atom of oxygen to form water. (britannica.com)
  • The dynamic modulation of protein function by phosphorylation plays an important role in regulating synaptic plasticity. (jneurosci.org)
  • We show that phosphorylation on serine-234 and serine-274 of rabphilin is dynamically regulated both under basal and stimulated conditions by the activity of kinases and phosphatases. (jneurosci.org)
  • Together, our studies show that phosphorylation of NSP2 involving CK1α controls viroplasm assembly. (osti.gov)
  • However, DA binding to D2-like receptors will reduce DARPP-32 Thr34 phosphorylation by inhibiting PKA and activating the protein phosphatase Calcineurin. (rndsystems.com)
  • In human pancreatic cancer cells, IER3 expression efficiently sustained ERK1/2 phosphorylation by inhibiting phosphatase PP2A activity. (jci.org)
  • Together, our data indicate that IER3 supports KRAS G12D -associated oncogenesis in the pancreas by sustaining ERK1/2 phosphorylation via phosphatase PP2A inhibition. (jci.org)
  • Another proposed mechanism protecting the TCR from random phosphorylation is based on the physical segregation of the complex from Src kinases, predicated on the existence of "lipid rafts" ( He and Marguet, 2008 ). (frontiersin.org)
  • Phosphorylation is the most common mechanism of regulating protein function and transmitting signals throughout the cell. (thermofisher.com)
  • Mechanism of oxidative stress-induced ASK1-catalyzed MKK6 phosphorylation. (uniprot.org)
  • This transport mechanism is phosphorylation dependent. (wikipedia.org)
  • The nuclear envelope localization of LBR is regulated through a phosphorylation network governed by ELYS, and defects in this phosphorylation network induce the aberrant phosphorylation and mislocalization of LBR. (biologists.org)
  • G. Discovery of Photosynthetic Phosphorylation. (worldcat.org)
  • Regulatory roles of phosphorylation include: Phosphorylation of Na+/K+-ATPase during the transport of sodium (Na+) and potassium (K+) ions across the cell membrane in osmoregulation to maintain homeostasis of the body's water content. (wikipedia.org)
  • In this regard, the identification and functional analysis of phosphosites are fundamental for understanding the molecular mechanisms and regulatory roles of protein phosphorylation. (nature.com)
  • Phosphorylation and de-phosphorylation play critical roles as a mode of signal transfer in biological processes. (biolegend.com)
  • Protein phosphorylation is involved in many mechanisms that contribute to neuronal plasticity, i.e. in the modulation of the information processing and storage properties of nerve cells resulting, ultimately, in the ability of the nervous system to learn. (springer.com)
  • Protein phosphorylation, catalyzed by kinases, is one of the fundamental mechanisms of regulating signaling pathways. (abcam.com)
  • In addition to activation of these pathways by tyrosine phosphorylation, several mechanisms of downregulating the response to insulin stimulation have also been identified. (diabetesjournals.org)
  • viruses, similar phosphorylation-dependent mechanisms may exist for other virus pathogens that require cytoplasmic virus factories for replication. (osti.gov)
  • In this presentation, we will describe part of the mechanisms that are involved in the reprogramming of oxidative phosphorylation in cancer. (hstalks.com)
  • Next, we will study the mechanisms that control oxidative phosphorylation at the level of the ATP synthase in cancer. (hstalks.com)
  • In this paper, we study adaptation mechanisms in a class of phosphorylation cycles where allosteric binding and gene autoregulation mechanisms regulate the phosphorylation processes. (rug.nl)
  • It is estimated that one-third of the proteins in the human proteome are substrates for phosphorylation at some point. (thermofisher.com)
  • We found that microwave irradiation generally provided the highest and most consistent levels of protein phosphorylation, regardless of the substrates examined in striatum and hippocampus. (cdc.gov)
  • A major goal of systems biology is to integrate all in vivo phosphorylation events into the context of an organism. (pnas.org)
  • the in vivo occurrence and physiological relevance of these putative phosphorylation events remains to be fully established. (jneurosci.org)
  • In vivo replication assays confirm that phosphorylation of T271 does not play a role in viral replication, while modification at T297 and T299 have dramatic and opposing effects on LT's ability to initiate replication from the viral origin. (mdpi.com)
  • Focused microwave irradiation of the brain preserves in vivo protein phosphorylation: comparison with other methods of sacrifice and analysis of multiple phosphoproteins. (cdc.gov)
  • Our results indicate that focused microwave irradiation sacrifice may be required to achieve biologically relevant data for the in vivo protein phosphorylation state of many phosphoproteins. (cdc.gov)
  • In this study, we compared preservation of the phosphorylation state of a variety of phosphoproteins in the brain following sacrifice of mice by decapitation, decapitation into liquid nitrogen and focused microwave irradiation. (cdc.gov)
  • The subcellular localization and function of this protein are modulated by post-translational modifications, including sumoylation, phosphorylation and polyubiquitination. (wikipedia.org)
  • Noteworthy increases in cardiac ventricle mass and in skeletal and cardiac muscle oxidative phosphorylation capacity arise when Pekin ducks hatch and attain an endothermic metabolic phenotype. (biologists.org)
  • Phosphorylation analysis from primary tissue, in contrast to immortalized cell lines, best represents events that are occurring in the basal physiological state of an organism even though tissues often contain heterogeneous populations of cells. (pnas.org)
  • Recent evidence confirms widespread histidine phosphorylation at both the 1 and 3 N-atoms of the imidazole ring Recent work from 2017 (preprinted at BioRxiv ) suggests widespread human protein phosphorylation on multiple non-canonical amino acids, including motifs containing phosphorylated histidine, aspartate, glutamate, arginine and lysine in HeLa cell extracts. (wikipedia.org)
  • Recent evidence (preprinted at BioRxiv) suggests widespread human protein phosphorylation on multiple non-canonical amino acids, including motifs containing phosphorylated histidine, aspartate, glutamate, arginine and lysine in HeLa cell extracts. (wikipedia.org)
  • Finally, we identified double phosphorylation motifs that may be involved in ordered phosphorylation. (pnas.org)