Biomaterial Database

Activation of adenylate cyclase by alcohols requires the nucleotide-binding protein. 1984

G R Luthin, and B Tabakoff

Ethanol was shown to activate adenylate cyclase in mouse striatal membranes, but significant activation of adenylate cyclase by ethanol concentrations below 500 mM was found only in the presence of 5'-guanylylimidodiphosphate [Gpp(NH)p] or other guanine nucleotides. Ethanol did not alter the amount of guanine nucleotide required for half-maximal activation of adenylate cyclase, but was found to further increase adenylate cyclase activity under conditions wherein the nucleotide binding protein was preloaded with Gpp(NH)p or when hydrolysis of added GTP was blocked using cholera toxin. The stimulation of adenylate cyclase activity by sodium fluoride was also accentuated by ethanol. Ethanol, propanol and butanol all increased adenylate cyclase activity in the presence of Gpp(NH)p, and their effects on adenylate cyclase activity were linearly correlated with their respective carbon chain lengths. Equivalent membrane concentrations of ethanol and chloroform produced similar increases in adenylate cyclase activity under conditions where hydrolysis of added GTP was inhibited. However, chloroform and ethanol had opposite effects on adenylate cyclase activity in assays containing GTP and membranes not treated with cholera toxin. The apparent Km of adenylate cyclase for Mg-ATP and the Arrhenius activation energy for the enzyme in membranes incubated with Gpp(NH)p were similar in the presence and absence of ethanol. Ethanol, in concentrations up to 750 mM, did not alter the pattern of stimulation of adenylate cyclase by calcium and calmodulin. Our results suggest that ethanol modifies the equilibrium for the interaction of the nucleotide-loaded G-protein with the catalytic unit of adenylate cyclase to favor formation of the active nucleotide-G-protein-catalytic unit complex.(ABSTRACT TRUNCATED AT 250 WORDS)

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008563	Membrane Lipids	Lipids, predominantly phospholipids, cholesterol and small amounts of glycolipids found in membranes including cellular and intracellular membranes. These lipids may be arranged in bilayers in the membranes with integral proteins between the layers and peripheral proteins attached to the outside. Membrane lipids are required for active transport, several enzymatic activities and membrane formation.	Cell Membrane Lipid,Cell Membrane Lipids,Membrane Lipid,Lipid, Cell Membrane,Lipid, Membrane,Lipids, Cell Membrane,Lipids, Membrane,Membrane Lipid, Cell,Membrane Lipids, Cell
D002118	Calcium	A basic element found in nearly all 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.	Coagulation Factor IV,Factor IV,Blood Coagulation Factor IV,Calcium-40,Calcium 40,Factor IV, Coagulation
D002147	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.	Calcium-Dependent Activator Protein,Calcium-Dependent Regulator,Bovine Activator Protein,Cyclic AMP-Phosphodiesterase Activator,Phosphodiesterase Activating Factor,Phosphodiesterase Activator Protein,Phosphodiesterase Protein Activator,Regulator, Calcium-Dependent,AMP-Phosphodiesterase Activator, Cyclic,Activating Factor, Phosphodiesterase,Activator Protein, Bovine,Activator Protein, Calcium-Dependent,Activator Protein, Phosphodiesterase,Activator, Cyclic AMP-Phosphodiesterase,Activator, Phosphodiesterase Protein,Calcium Dependent Activator Protein,Calcium Dependent Regulator,Cyclic AMP Phosphodiesterase Activator,Factor, Phosphodiesterase Activating,Protein Activator, Phosphodiesterase,Protein, Bovine Activator,Protein, Calcium-Dependent Activator,Protein, Phosphodiesterase Activator,Regulator, Calcium Dependent
D002352	Carrier Proteins	Proteins that bind or transport specific substances in the blood, within the cell, or across cell membranes.	Binding Proteins,Carrier Protein,Transport Protein,Transport Proteins,Binding Protein,Protein, Carrier,Proteins, Carrier
D002373	Cyclic AMP Receptor Protein	A transcriptional regulator in prokaryotes which, when activated by binding cyclic AMP, acts at several promoters. Cyclic AMP receptor protein was originally identified as a catabolite gene activator protein. It was subsequently shown to regulate several functions unrelated to catabolism, and to be both a negative and a positive regulator of transcription. Cell surface cyclic AMP receptors are not included (CYCLIC AMP RECEPTORS), nor are the eukaryotic cytoplasmic cyclic AMP receptor proteins, which are the regulatory subunits of CYCLIC AMP-DEPENDENT PROTEIN KINASES.	Catabolic Gene Activators,Catabolite Activator Protein,Catabolite Gene Activator Protein,Catabolite Gene Activator Proteins,Activator Protein, Catabolite,Activator Proteins, Catabolite,Activator, Catabolic Gene,Activators, Catabolic Gene,Catabolic Gene Activator,Catabolite Activator Proteins,Catabolite Regulator Protein,Catabolite Regulator Proteins,Cyclic AMP Receptor Proteins,Gene Activator, Catabolic,Gene Activators, Catabolic,Protein, Catabolite Activator,Protein, Catabolite Regulator,Proteins, Catabolite Activator,Proteins, Catabolite Regulator,Regulator Protein, Catabolite,Regulator Proteins, Catabolite,cAMP Receptor Protein,cAMP Receptor Proteins,Protein, cAMP Receptor,Proteins, cAMP Receptor,Receptor Protein, cAMP,Receptor Proteins, cAMP
D002725	Chloroform	A commonly used laboratory solvent. It was previously used as an anesthetic, but was banned from use in the U.S. due to its suspected carcinogenicity.	Trichloromethane
D002772	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.	Cholera Toxin A,Cholera Toxin B,Cholera Toxin Protomer A,Cholera Toxin Protomer B,Cholera Toxin Subunit A,Cholera Toxin Subunit B,Choleragen,Choleragenoid,Cholera Enterotoxin CT,Cholera Exotoxin,Cholera Toxin A Subunit,Cholera Toxin B Subunit,Procholeragenoid,Enterotoxin CT, Cholera,Exotoxin, Cholera,Toxin A, Cholera,Toxin B, Cholera,Toxin, Cholera
D004298	Dopamine	One of the catecholamine NEUROTRANSMITTERS in the brain. It is derived from TYROSINE and is the precursor to NOREPINEPHRINE and EPINEPHRINE. Dopamine is a major transmitter in the extrapyramidal system of the brain, and important in regulating movement. A family of receptors (RECEPTORS, DOPAMINE) mediate its action.	Hydroxytyramine,3,4-Dihydroxyphenethylamine,4-(2-Aminoethyl)-1,2-benzenediol,Dopamine Hydrochloride,Intropin,3,4 Dihydroxyphenethylamine,Hydrochloride, Dopamine
D004789	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.	Activation, Enzyme,Activations, Enzyme,Enzyme Activations