rap GTP-Binding Proteins: A family of MONOMERIC GTP-BINDING PROTEINS that are related to RAS PROTEINS.This enzyme was formerly listed as EC 184.108.40.206.GTP-Binding Proteins: Regulatory proteins that act as molecular switches. They control a wide range of biological processes including: receptor signaling, intracellular signal transduction pathways, and protein synthesis. Their activity is regulated by factors that control their ability to bind to and hydrolyze GTP to GDP. EC 3.6.1.-.rab3 GTP-Binding Proteins: A genetically related subfamily of RAB GTP-BINDING PROTEINS involved in calcium-dependent EXOCYTOSIS. This enzyme was formerly listed as EC 220.127.116.11.rap1 GTP-Binding Proteins: A genetically related subfamily of RAP GTP-BINDING PROTEINS that share homology with RAS PROTEINS. They bind to Ras effectors but do not activate them, therefore they may antagonize the effects of RAS PROTEINS. This enzyme was formerly listed as EC 18.104.22.168.Guanosine Triphosphate: Guanosine 5'-(tetrahydrogen triphosphate). A guanine nucleotide containing three phosphate groups esterified to the sugar moiety.Guanosine 5'-O-(3-Thiotriphosphate): Guanosine 5'-(trihydrogen diphosphate), monoanhydride with phosphorothioic acid. A stable GTP analog which enjoys a variety of physiological actions such as stimulation of guanine nucleotide-binding proteins, phosphoinositide hydrolysis, cyclic AMP accumulation, and activation of specific proto-oncogenes.rhoB GTP-Binding Protein: A GTP-BINDING PROTEIN involved in regulating a signal transduction pathway that controls assembly of focal adhesions and actin stress fibers. This enzyme was formerly listed as EC 22.214.171.124.Monomeric GTP-Binding Proteins: A class of monomeric, low molecular weight (20-25 kDa) GTP-binding proteins that regulate a variety of intracellular processes. The GTP bound form of the protein is active and limited by its inherent GTPase activity, which is controlled by an array of GTPase activators, GDP dissociation inhibitors, and guanine nucleotide exchange factors. This enzyme was formerly listed as EC 126.96.36.199GTP Phosphohydrolases: Enzymes that hydrolyze GTP to GDP. EC 3.6.1.-.Adenosine Diphosphate Ribose: An ester formed between the aldehydic carbon of RIBOSE and the terminal phosphate of ADENOSINE DIPHOSPHATE. It is produced by the hydrolysis of nicotinamide-adenine dinucleotide (NAD) by a variety of enzymes, some of which transfer an ADP-ribosyl group to target proteins.Guanosine Diphosphate: A guanine nucleotide containing two phosphate groups esterified to the sugar moiety.rac GTP-Binding Proteins: A sub-family of RHO GTP-BINDING PROTEINS that is involved in regulating the organization of cytoskeletal filaments. This enzyme was formerly listed as EC 188.8.131.52.rho GTP-Binding Proteins: A large family of MONOMERIC GTP-BINDING PROTEINS that are involved in regulation of actin organization, gene expression and cell cycle progression. This enzyme was formerly listed as EC 184.108.40.206.rab GTP-Binding Proteins: A large family of MONOMERIC GTP-BINDING PROTEINS that play a key role in cellular secretory and endocytic pathways. EC 3.6.1.-.Virulence Factors, Bordetella: A set of BACTERIAL ADHESINS and TOXINS, BIOLOGICAL produced by BORDETELLA organisms that determine the pathogenesis of BORDETELLA INFECTIONS, such as WHOOPING COUGH. They include filamentous hemagglutinin; FIMBRIAE PROTEINS; pertactin; PERTUSSIS TOXIN; ADENYLATE CYCLASE TOXIN; dermonecrotic toxin; tracheal cytotoxin; Bordetella LIPOPOLYSACCHARIDES; and tracheal colonization factor.cdc42 GTP-Binding Protein: A member of the Rho family of MONOMERIC GTP-BINDING PROTEINS. It is associated with a diverse array of cellular functions including cytoskeletal changes, filopodia formation and transport through the GOLGI APPARATUS. This enzyme was formerly listed as EC 220.127.116.11.Thionucleotides: Nucleotides in which the base moiety is substituted with one or more sulfur atoms.Pertussis Toxin: One of the virulence factors produced by BORDETELLA PERTUSSIS. It is a multimeric protein composed of five subunits S1 - S5. S1 contains mono ADPribose transferase activity.rhoA GTP-Binding Protein: A RHO GTP-BINDING PROTEIN involved in regulating signal transduction pathways that control assembly of focal adhesions and actin stress fibers. This enzyme was formerly listed as EC 18.104.22.168.ADP-Ribosylation Factors: MONOMERIC GTP-BINDING PROTEINS that were initially recognized as allosteric activators of the MONO(ADP-RIBOSE) TRANSFERASE of the CHOLERA TOXIN catalytic subunit. They are involved in vesicle trafficking and activation of PHOSPHOLIPASE D. This enzyme was formerly listed as EC 22.214.171.124Molecular 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.Aluminum Compounds: Inorganic compounds that contain aluminum as an integral part of the molecule.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.Guanine Nucleotidesrab2 GTP-Binding Protein: A protein involved in transport between the ENDOPLASMIC RETICULUM and the GOLGI APPARATUS. This enzyme was formerly listed as EC 126.96.36.199.Guanylyl Imidodiphosphate: A non-hydrolyzable analog of GTP, in which the oxygen atom bridging the beta to the gamma phosphate is replaced by a nitrogen atom. It binds tightly to G-protein in the presence of Mg2+. The nucleotide is a potent stimulator of ADENYLYL CYCLASES.Botulinum Toxins: Toxic proteins produced from the species CLOSTRIDIUM BOTULINUM. The toxins are synthesized as a single peptide chain which is processed into a mature protein consisting of a heavy chain and light chain joined via a disulfide bond. The botulinum toxin light chain is a zinc-dependent protease which is released from the heavy chain upon ENDOCYTOSIS into PRESYNAPTIC NERVE ENDINGS. Once inside the cell the botulinum toxin light chain cleaves specific SNARE proteins which are essential for secretion of ACETYLCHOLINE by SYNAPTIC VESICLES. This inhibition of acetylcholine release results in muscular PARALYSIS.ral GTP-Binding Proteins: A family of ubiquitously expressed MONOMERIC GTP-BINDING PROTEINS that are involved in intracellular signal transduction. This enzyme was formerly listed as EC 188.8.131.52.rab1 GTP-Binding Proteins: A genetically related subfamily of RAB GTP-BINDING PROTEINS involved in vesicle transport between the ENDOPLASMIC RETICULUM and the GOLGI APPARATUS and through early Golgi compartments. This enzyme was formerly listed as EC 184.108.40.206.Wasp Venoms: Venoms produced by the wasp (Vespid) family of stinging insects, including hornets; the venoms contain enzymes, biogenic amines, histamine releasing factors, kinins, toxic polypeptides, etc., and are similar to bee venoms.rho-Specific Guanine Nucleotide Dissociation Inhibitors: A subcategory of guanine nucleotide dissociation inhibitors that are specific for RHO GTP-BINDING PROTEINS.cdc42 GTP-Binding Protein, Saccharomyces cerevisiae: A member of the Rho family of MONOMERIC GTP-BINDING PROTEINS from SACCHAROMYCES CEREVISIAE. It is involved in morphological events related to the cell cycle. This enzyme was formerly listed as EC 220.127.116.11.rac1 GTP-Binding Protein: A rac GTP-binding protein involved in regulating actin filaments at the plasma membrane. It controls the development of filopodia and lamellipodia in cells and thereby influences cellular motility and adhesion. It is also involved in activation of NADPH OXIDASE. This enzyme was formerly listed as EC 18.104.22.168.ADP Ribose Transferases: Enzymes that transfer the ADP-RIBOSE group of NAD or NADP to proteins or other small molecules. Transfer of ADP-ribose to water (i.e., hydrolysis) is catalyzed by the NADASES. The mono(ADP-ribose)transferases transfer a single ADP-ribose. POLY(ADP-RIBOSE) POLYMERASES transfer multiple units of ADP-ribose to protein targets, building POLY ADENOSINE DIPHOSPHATE RIBOSE in linear or branched chains.Cell Membrane: The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.Septins: A family of GTP-binding proteins that were initially identified in YEASTS where they were shown to initiate the process of septation and bud formation. Septins form into hetero-oligomeric complexes that are comprised of several distinct septin subunits. These complexes can act as cytoskeletal elements that play important roles in CYTOKINESIS, cytoskeletal reorganization, BIOLOGICAL TRANSPORT, and membrane dynamics.Guanine Nucleotide Dissociation Inhibitors: Protein factors that inhibit the dissociation of GDP from GTP-BINDING PROTEINS.GTPase-Activating Proteins: Proteins that activate the GTPase of specific GTP-BINDING PROTEINS.rab3A GTP-Binding Protein: The most abundant member of the RAB3 GTP-BINDING PROTEINS. It is involved in calcium-dependent EXOCYTOSIS and is localized to neurons and neuroendocrine cells. This enzyme was formerly listed as EC 22.214.171.124.Fluorides: Inorganic salts of hydrofluoric acid, HF, in which the fluorine atom is in the -1 oxidation state. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed) Sodium and stannous salts are commonly used in dentifrices.rab4 GTP-Binding Proteins: A genetically related subfamily of RAB GTP-BINDING PROTEINS involved in recycling of proteins such as cell surface receptors from early endosomes to the cell surface. This enzyme was formerly listed as EC 126.96.36.199.Cholera Toxin: An ENTEROTOXIN from VIBRIO CHOLERAE. It consists of two major protomers, the heavy (H) or A subunit and the B protomer which consists of 5 light (L) or B subunits. The catalytic A subunit is proteolytically cleaved into fragments A1 and A2. The A1 fragment is a MONO(ADP-RIBOSE) TRANSFERASE. The B protomer binds cholera toxin to intestinal epithelial cells, and facilitates the uptake of the A1 fragment. The A1 catalyzed transfer of ADP-RIBOSE to the alpha subunits of heterotrimeric G PROTEINS activates the production of CYCLIC AMP. Increased levels of cyclic AMP are thought to modulate release of fluid and electrolytes from intestinal crypt cells.Adenylate Cyclase Toxin: One of the virulence factors produced by virulent BORDETELLA organisms. It is a bifunctional protein with both ADENYLYL CYCLASES and hemolysin components.Proto-Oncogene Proteins p21(ras): Cellular proteins encoded by the H-ras, K-ras and N-ras genes. The proteins have GTPase activity and are involved in signal transduction as monomeric GTP-binding proteins. Elevated levels of p21 c-ras have been associated with neoplasia. This enzyme was formerly listed as EC 188.8.131.52.Heterotrimeric GTP-Binding Proteins: GTP-BINDING PROTEINS that contain three non-identical subunits. They are found associated with members of the seven transmembrane domain superfamily of G-PROTEIN-COUPLED RECEPTORS. Upon activation the GTP-BINDING PROTEIN ALPHA SUBUNIT of the complex dissociates leaving a dimer of a GTP-BINDING PROTEIN BETA SUBUNIT bound to a GTP-BINDING PROTEIN GAMMA SUBUNIT.ADP-Ribosylation Factor 1: ADP-RIBOSYLATION FACTOR 1 is involved in regulating intracellular transport by modulating the interaction of coat proteins with organelle membranes in the early secretory pathway. It is a component of COAT PROTEIN COMPLEX I. This enzyme was formerly listed as EC 184.108.40.206.Kinetics: The rate dynamics in chemical or physical systems.Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.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.GTP-Binding Protein alpha Subunit, Gi2: A PERTUSSIS TOXIN-sensitive GTP-binding protein alpha subunit. It couples with a variety of CELL SURFACE RECEPTORS, has been implicated in INTERLEUKIN-12 production, and may play a role in INFLAMMATORY BOWEL DISEASES.Cloning, Molecular: The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.Molecular Weight: The sum of the weight of all the atoms in a molecule.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 220.127.116.11), it is commonly used in the literature to refer to broad variety of enzymes that specifically catalyze the hydrolysis of PHOSPHATIDYLINOSITOLS.rab5 GTP-Binding Proteins: A genetically related subfamily of RAB GTP-BINDING PROTEINS involved in transport from the cell membrane to early endosomes. This enzyme was formerly listed as EC 18.104.22.168.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.Transducin: A heterotrimeric GTP-binding protein that mediates the light activation signal from photolyzed rhodopsin to cyclic GMP phosphodiesterase and is pivotal in the visual excitation process. Activation of rhodopsin on the outer membrane of rod and cone cells causes GTP to bind to transducin followed by dissociation of the alpha subunit-GTP complex from the beta/gamma subunits of transducin. The alpha subunit-GTP complex activates the cyclic GMP phosphodiesterase which catalyzes the hydrolysis of cyclic GMP to 5'-GMP. This leads to closure of the sodium and calcium channels and therefore hyperpolarization of the rod cells. EC 3.6.1.-.Adenylate Cyclase: An enzyme of the lyase class that catalyzes the formation of CYCLIC AMP and pyrophosphate from ATP. EC 22.214.171.124.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.Guanine Nucleotide Exchange Factors: Protein factors that promote the exchange of GTP for GDP bound to GTP-BINDING PROTEINS.GTP-Binding Protein alpha Subunits, Gi-Go: A family of heterotrimeric GTP-binding protein alpha subunits that were originally identified by their ability to inhibit ADENYLYL CYCLASES. Members of this family can couple to beta and gamma G-protein subunits that activate POTASSIUM CHANNELS. The Gi-Go part of the name is also spelled Gi/Go.GTP-Binding Protein alpha Subunits, Gs: A family of heterotrimeric GTP-binding protein alpha subunits that activate ADENYLYL CYCLASES.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.Cell Line: Established cell cultures that have the potential to propagate indefinitely.Recombinant Proteins: Proteins prepared by recombinant DNA technology.Protein Prenylation: A post-translational modification of proteins by the attachment of an isoprenoid to the C-terminal cysteine residue. The isoprenoids used, farnesyl diphosphate or geranylgeranyl diphosphate, are derived from the same biochemical pathway that produces cholesterol.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.Aluminum: A metallic element that has the atomic number 13, atomic symbol Al, and atomic weight 26.98.Exocytosis: Cellular release of material within membrane-limited vesicles by fusion of the vesicles with the CELL MEMBRANE.Electrophoresis, Polyacrylamide Gel: Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.Cytosol: Intracellular fluid from the cytoplasm after removal of ORGANELLES and other insoluble cytoplasmic components.Sodium Fluoride: A source of inorganic fluoride which is used topically to prevent dental caries.ras Proteins: Small, monomeric GTP-binding proteins encoded by ras genes (GENES, RAS). The protooncogene-derived protein, PROTO-ONCOGENE PROTEIN P21(RAS), plays a role in normal cellular growth, differentiation and development. The oncogene-derived protein (ONCOGENE PROTEIN P21(RAS)) can play a role in aberrant cellular regulation during neoplastic cell transformation (CELL TRANSFORMATION, NEOPLASTIC). This enzyme was formerly listed as EC 126.96.36.199.Phospholipase D: An enzyme found mostly in plant tissue. It hydrolyzes glycerophosphatidates with the formation of a phosphatidic acid and a nitrogenous base such as choline. This enzyme also catalyzes transphosphatidylation reactions. EC 188.8.131.52.Rod Cell Outer Segment: The portion of a retinal rod cell situated between the ROD INNER SEGMENT and the RETINAL PIGMENT EPITHELIUM. It contains a stack of photosensitive disk membranes laden with RHODOPSIN.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.Cell Fractionation: Techniques to partition various components of the cell into SUBCELLULAR FRACTIONS.ras GTPase-Activating Proteins: PROTEINS that specifically activate the GTP-phosphohydrolase activity of RAS PROTEINS.Golgi Apparatus: A stack of flattened vesicles that functions in posttranslational processing and sorting of proteins, receiving them from the rough ENDOPLASMIC RETICULUM and directing them to secretory vesicles, LYSOSOMES, or the CELL MEMBRANE. The movement of proteins takes place by transfer vesicles that bud off from the rough endoplasmic reticulum or Golgi apparatus and fuse with the Golgi, lysosomes or cell membrane. (From Glick, Glossary of Biochemistry and Molecular Biology, 1990)Macromolecular Substances: Compounds and molecular complexes that consist of very large numbers of atoms and are generally over 500 kDa in size. In biological systems macromolecular substances usually can be visualized using ELECTRON MICROSCOPY and are distinguished from ORGANELLES by the lack of a membrane structure.ras Guanine Nucleotide Exchange Factors: A family of GUANINE NUCLEOTIDE EXCHANGE FACTORS that are specific for RAS PROTEINS.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.ran GTP-Binding Protein: A monomeric GTP-binding protein involved in nucleocytoplasmic transport of proteins into the nucleus and RNA into the cytoplasm. This enzyme was formerly listed as EC 184.108.40.206.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.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.Rhodopsin: A purplish-red, light-sensitive pigment found in RETINAL ROD CELLS of most vertebrates. It is a complex consisting of a molecule of ROD OPSIN and a molecule of 11-cis retinal (RETINALDEHYDE). Rhodopsin exhibits peak absorption wavelength at about 500 nm.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.Binding Sites: The parts of a macromolecule that directly participate in its specific combination with another molecule.Oncogene Protein p21(ras): Transforming protein encoded by ras oncogenes. Point mutations in the cellular ras gene (c-ras) can also result in a mutant p21 protein that can transform mammalian cells. Oncogene protein p21(ras) has been directly implicated in human neoplasms, perhaps accounting for as much as 15-20% of all human tumors. This enzyme was formerly listed as EC 220.127.116.11.Blood Platelets: Non-nucleated disk-shaped cells formed in the megakaryocyte and found in the blood of all mammals. They are mainly involved in blood coagulation.3',5'-Cyclic-GMP Phosphodiesterases: Enzymes that catalyze the hydrolysis of cyclic GMP to yield guanosine-5'-phosphate.Affinity Labels: Analogs of those substrates or compounds which bind naturally at the active sites of proteins, enzymes, antibodies, steroids, or physiological receptors. These analogs form a stable covalent bond at the binding site, thereby acting as inhibitors of the proteins or steroids.Brain Chemistry: Changes in the amounts of various chemicals (neurotransmitters, receptors, enzymes, and other metabolites) specific to the area of the central nervous system contained within the head. These are monitored over time, during sensory stimulation, or under different disease states.