Biomaterial Database

Studies concerning a GTP regulatory subunit of rat luteal adenylate cyclase. 1984

P J McIlroy, and E R Bergert

The ADP-ribosylation of rat luteal membrane proteins has been investigated. In the presence of cholera toxin two membrane proteins, Mr 115,000 and 46,000, incorporated [32P]ADP-ribose from [32P]NAD+. The larger protein also incorporated [32P]ADP-ribose in the absence of cholera toxin. The smaller protein was identified as the guanine nucleotide regulatory protein of adenylate cyclase. To facilitate studies concerning this species, a simple and convenient method of measuring ADP-ribose incorporation into the protein was developed. Levels of the protein were found to be approximately equal to those of the hCG receptor and 7- to 10-fold higher than those of the beta-adrenergic receptor. Luteinization of rat ovaries by injection of hCG indicated that G/F concentrations increased approximately 2-fold over a 5- to 11-day period, and correlated significantly with increased beta-adrenergic receptors, and beta-adrenergic and NaF-stimulated adenylate cyclase, but not with hCG receptors or hCG-stimulated adenylate cyclase. The distribution of the G/F protein in purified luteal membrane preparations mimicked the distribution of adenylate cyclase activity. No evidence could be found for hormonally induced alterations in ADP-ribose incorporation into this protein under either ribosylation or adenylate cyclase conditions. The exact role of the protein in the activation of rat luteal adenylate cyclase has yet to be determined.

UI	MeSH Term	Description	Entries
D008565	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.	Cell Membrane Protein,Cell Membrane Proteins,Cell Surface Protein,Cell Surface Proteins,Integral Membrane Proteins,Membrane-Associated Protein,Surface Protein,Surface Proteins,Integral Membrane Protein,Membrane Protein,Membrane-Associated Proteins,Membrane Associated Protein,Membrane Associated Proteins,Membrane Protein, Cell,Membrane Protein, Integral,Membrane Proteins, Integral,Protein, Cell Membrane,Protein, Cell Surface,Protein, Integral Membrane,Protein, Membrane,Protein, Membrane-Associated,Protein, Surface,Proteins, Cell Membrane,Proteins, Cell Surface,Proteins, Integral Membrane,Proteins, Membrane,Proteins, Membrane-Associated,Proteins, Surface,Surface Protein, Cell
D002499	Centrifugation, Density Gradient	Separation of particles according to density by employing a gradient of varying densities. At equilibrium each particle settles in the gradient at a point equal to its density. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)	Centrifugations, Density Gradient,Density Gradient Centrifugation,Density Gradient Centrifugations,Gradient Centrifugation, Density,Gradient Centrifugations, Density
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
D003338	Corpus Luteum	The yellow body derived from the ruptured OVARIAN FOLLICLE after OVULATION. The process of corpus luteum formation, LUTEINIZATION, is regulated by LUTEINIZING HORMONE.	Corpora Lutea,Lutea, Corpora
D004591	Electrophoresis, Polyacrylamide Gel	Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.	Polyacrylamide Gel Electrophoresis,SDS-PAGE,Sodium Dodecyl Sulfate-PAGE,Gel Electrophoresis, Polyacrylamide,SDS PAGE,Sodium Dodecyl Sulfate PAGE,Sodium Dodecyl Sulfate-PAGEs
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
D005260	Female		Females
D006063	Chorionic Gonadotropin	A gonadotropic glycoprotein hormone produced primarily by the PLACENTA. Similar to the pituitary LUTEINIZING HORMONE in structure and function, chorionic gonadotropin is involved in maintaining the CORPUS LUTEUM during pregnancy. CG consists of two noncovalently linked subunits, alpha and beta. Within a species, the alpha subunit is virtually identical to the alpha subunits of the three pituitary glycoprotein hormones (TSH, LH, and FSH), but the beta subunit is unique and confers its biological specificity (CHORIONIC GONADOTROPIN, BETA SUBUNIT, HUMAN).	Chorionic Gonadotropin, Human,HCG (Human Chorionic Gonadotropin),Biogonadil,Choriogonadotropin,Choriogonin,Chorulon,Gonabion,Human Chorionic Gonadotropin,Pregnyl,Gonadotropin, Chorionic,Gonadotropin, Human Chorionic
D006160	Guanosine Triphosphate	Guanosine 5'-(tetrahydrogen triphosphate). A guanine nucleotide containing three phosphate groups esterified to the sugar moiety.	GTP,Triphosphate, Guanosine
D000246	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.	ADP Ribose,Adenosine Diphosphoribose,ADP-Ribose,ADPribose,Adenosine 5'-Diphosphoribose,5'-Diphosphoribose, Adenosine,Adenosine 5' Diphosphoribose,Diphosphate Ribose, Adenosine,Diphosphoribose, Adenosine,Ribose, ADP,Ribose, Adenosine Diphosphate