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.Trifluoperazine: A phenothiazine with actions similar to CHLORPROMAZINE. It is used as an antipsychotic and an antiemetic.Calmodulin-Binding Proteins: Proteins which bind calmodulin. They are found in many tissues and have a variety of functions including F-actin cross-linking properties, inhibition of cyclic nucleotide phosphodiesterase and calcium and magnesium ATPases.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.Calcium-Binding Proteins: Proteins to which calcium ions are bound. They can act as transport proteins, regulator proteins, or activator proteins. They typically contain EF HAND MOTIFS.Myosin-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.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.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.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.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.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.Sulfonamides: A group of compounds that contain the structure SO2NH2.Binding Sites: The parts of a macromolecule that directly participate in its specific combination with another molecule.Kinetics: The rate dynamics in chemical or physical systems.Egtazic Acid: A chelating agent relatively more specific for calcium and less toxic than EDETIC ACID.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)2',3'-Cyclic-Nucleotide Phosphodiesterases: Nucleoside-2',3'-cyclic phosphate nucleotidohydrolase. Enzymes that catalyze the hydrolysis of the 2'- or 3'- phosphate bonds of 2',3'-cyclic nucleotides. Also hydrolyzes nucleoside monophosphates. Includes EC 3.1.4.16 and EC 3.1.4.37. EC 3.1.4.-.Chlorpromazine: The prototypical phenothiazine antipsychotic drug. Like the other drugs in this class chlorpromazine's antipsychotic actions are thought to be due to long-term adaptation by the brain to blocking DOPAMINE RECEPTORS. Chlorpromazine has several other actions and therapeutic uses, including as an antiemetic and in the treatment of intractable hiccup.Calcium-Transporting ATPases: Cation-transporting proteins that utilize the energy of ATP hydrolysis for the transport of CALCIUM. They differ from CALCIUM CHANNELS which allow calcium to pass through a membrane without the use of energy.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.Phosphorylation: The introduction of a phosphoryl group into a compound through the formation of an ester bond between the compound and a phosphorus moiety.3',5'-Cyclic-AMP Phosphodiesterases: Enzymes that catalyze the hydrolysis of CYCLIC AMP to form adenosine 5'-phosphate. The enzymes are widely distributed in animal tissue and control the level of intracellular cyclic AMP. Many specific enzymes classified under this heading demonstrate additional spcificity for 3',5'-cyclic IMP and CYCLIC GMP.Neurogranin: A BRAIN-specific substrate for PROTEIN KINASE C that binds CALMODULIN and is involved in regulation of CALCIUM SIGNALING.Sesterterpenes: Terpenes of five units of HEMITERPENES, formed from geranylfarnesyl pyrophosphate.Melitten: Basic polypeptide from the venom of the honey bee (Apis mellifera). It contains 26 amino acids, has cytolytic properties, causes contracture of muscle, releases histamine, and disrupts surface tension, probably due to lysis of cell and mitochondrial membranes.Cyclic Nucleotide Phosphodiesterases, Type 1: A CALCIUM and CALMODULIN-dependent cyclic nucleotide phosphodiesterase subfamily. The three members of this family are referred to as type 1A, type 1B, and type 1C and are each product of a distinct gene. In addition, multiple enzyme variants of each subtype can be produced due to multiple alternative mRNA splicing. Although the type 1 enzymes are classified as 3',5'-cyclic-AMP phosphodiesterases (EC 3.1.4.17), some members of this class have additional specificity for CYCLIC GMP.Calcineurin: A CALCIUM and CALMODULIN-dependent serine/threonine protein phosphatase that is composed of the calcineurin A catalytic subunit and the calcineurin B regulatory subunit. Calcineurin has been shown to dephosphorylate a number of phosphoproteins including HISTONES; MYOSIN LIGHT CHAIN; and the regulatory subunits of CAMP-DEPENDENT PROTEIN KINASES. It is involved in the regulation of signal transduction and is the target of an important class of immunophilin-immunosuppressive drug complexes.Calcium-Calmodulin-Dependent Protein Kinase Type 1: A monomeric calcium-calmodulin-dependent protein kinase subtype that is expressed in a broad variety of mammalian cell types. Its expression is regulated by the action of CALCIUM-CALMODULIN-DEPENDENT PROTEIN KINASE KINASE. Several isoforms of this enzyme subtype are encoded by distinct genes.Phenothiazines: Compounds containing dibenzo-1,4-thiazine. Some of them are neuroactive.Ca(2+) Mg(2+)-ATPaseParamecium: A genus of ciliate protozoa that is often large enough to be seen by the naked eye. Paramecia are commonly used in genetic, cytological, and other research.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.Peptide Fragments: Partial proteins formed by partial hydrolysis of complete proteins or generated through PROTEIN ENGINEERING techniques.EF Hand Motifs: Calcium-binding motifs composed of two helices (E and F) joined by a loop. Calcium is bound by the loop region. These motifs are found in many proteins that are regulated by calcium.Prenylamine: A drug formerly used in the treatment of angina pectoris but superseded by less hazardous drugs. Prenylamine depletes myocardial catecholamine stores and has some calcium channel blocking activity. (From Martindale, The Extra Pharmacopoeia, 30th ed, p1406)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.Protein Conformation: The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).Brain: The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.Protein Kinases: A family of enzymes that catalyze the conversion of ATP and a protein to ADP and a phosphoprotein.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.Phosphorylase Kinase: An enzyme that catalyzes the conversion of ATP and PHOSPHORYLASE B to ADP and PHOSPHORYLASE A.Chickens: Common name for the species Gallus gallus, the domestic fowl, in the family Phasianidae, order GALLIFORMES. It is descended from the red jungle fowl of SOUTHEAST ASIA.Calcium Signaling: Signal transduction mechanisms whereby calcium mobilization (from outside the cell or from intracellular storage pools) to the cytoplasm is triggered by external stimuli. Calcium signals are often seen to propagate as waves, oscillations, spikes, sparks, or puffs. The calcium acts as an intracellular messenger by activating calcium-responsive proteins.Phosphoric Diester Hydrolases: A class of enzymes that catalyze the hydrolysis of one of the two ester bonds in a phosphodiester compound. EC 3.1.4.GizzardTroponin: One of the minor protein components of skeletal muscle. Its function is to serve as the calcium-binding component in the troponin-tropomyosin B-actin-myosin complex by conferring calcium sensitivity to the cross-linked actin and myosin filaments.Electrophoresis, Polyacrylamide Gel: Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.Chromatography, Affinity: A chromatographic technique that utilizes the ability of biological molecules to bind to certain ligands specifically and reversibly. It is used in protein biochemistry. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Spectrometry, Fluorescence: Measurement of the intensity and quality of fluorescence.Benzylamines: Toluenes in which one hydrogen of the methyl group is substituted by an amino group. Permitted are any substituents on the benzene ring or the amino group.Fluphenazine: A phenothiazine used in the treatment of PSYCHOSES. Its properties and uses are generally similar to those of CHLORPROMAZINE.Molecular Weight: The sum of the weight of all the atoms in a molecule.Troponin C: One of the three polypeptide chains that make up the TROPONIN complex of skeletal muscle. It is a calcium-binding protein.Myosins: A diverse superfamily of proteins that function as translocating proteins. They share the common characteristics of being able to bind ACTINS and hydrolyze MgATP. Myosins generally consist of heavy chains which are involved in locomotion, and light chains which are involved in regulation. Within the structure of myosin heavy chain are three domains: the head, the neck and the tail. The head region of the heavy chain contains the actin binding domain and MgATPase domain which provides energy for locomotion. The neck region is involved in binding the light-chains. The tail region provides the anchoring point that maintains the position of the heavy chain. The superfamily of myosins is organized into structural classes based upon the type and arrangement of the subunits they contain.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.Recombinant Proteins: Proteins prepared by recombinant DNA technology.Myosin Type I: A subclass of myosins found generally associated with actin-rich membrane structures such as filopodia. Members of the myosin type I family are ubiquitously expressed in eukaryotes. The heavy chains of myosin type I lack coiled-coil forming sequences in their tails and therefore do not dimerize.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)Adenylate Cyclase: An enzyme of the lyase class that catalyzes the formation of CYCLIC AMP and pyrophosphate from ATP. EC 4.6.1.1.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.Bee Venoms: Venoms obtained from Apis mellifera (honey bee) and related species. They contain various enzymes, polypeptide toxins, and other substances, some of which are allergenic or immunogenic or both. These venoms were formerly used in rheumatism to stimulate the pituitary-adrenal system.Erythrocyte Membrane: The semi-permeable outer structure of a red blood cell. It is known as a red cell 'ghost' after HEMOLYSIS.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.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.Cell Membrane: The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.Models, Molecular: Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.