[Effect of C-terminal peptide of G-protein alfa(s)-subunit on regulation of adenylate cyclase and protein kinase A activities by biogenic amines and glucagon in mollusc and rat muscles].
The peptide synthesised by us: 387-394-amide (10(-7)-10(-4) M), in a dose dependent manner decreases activities of adenyl cyclase and proteinkinase A evoked by serotonine and glucagon in smooth muscles of the freshwater bivalve mollusc Anodonta cygnea and that evoked by beta-agonist isoproterenol--in the rat skeletal muscles. Even in concentration 10(-7) M, the peptide completely eliminates potentiation of the hormones' stimulating effect on adenylyl cyclase activity with the non-hydrolizable analogue of guanine nucleotides (Gpp[NH]p). At the same time, the peptide does not affect stimulation of the adenylyl cyclase activity with non-hormonal agents (NaF, Gpp[NH]p and forkolin). In the presence of the peptide, inhibiting effects of the hormones on activities of adenylyl cyclase and protein kinase A will be preserved. The findings reveal the importance of the G-protein alpha s-subunit's C-terminal regional of a stimulating type for its functional coupling with receptors of a serpentine type, and elucidate the molecular mechanisms of interaction between the G-protein and the receptor.
Shpakov
A O
AO
I. M. Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Acad. Sci., 194223, St. Petersburg, Pr. M. Thoreza, 44, Russia.
Korol'kov
V I
VI
Plesneva
S A
SA
Kuznetsova
L A
LA
Pertseva
M N
MN
D000067956:Adenylyl Cyclase Inhibitors; D000262:Adenylyl Cyclases / Q000378:metabolism*; D000818:Animals; D017868:Cyclic AMP-Dependent Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D004789:Enzyme Activation; D044385:GTP-Binding Protein alpha Subunits / Q000378:metabolism*; D008974:Mollusca / Q000201:enzymology; D018482:Muscle, Skeletal / Q000201:enzymology; D009130:Muscle, Smooth / Q000201:enzymology; D009132:Muscles / Q000201:enzymology*; D009842:Oligopeptides / Q000494:pharmacology*; D010446:Peptide Fragments / Q000494:pharmacology; D051381:Rats; D043562:Receptors, G-Protein-Coupled / Q000378:metabolism*; D018027:Receptors, Glucagon / Q000378:metabolism; D011985:Receptors, Serotonin / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects; D013045:Species Specificity
D000067956:Adenylyl Cyclase Inhibitors; D044385:GTP-Binding Protein alpha Subunits; D009842:Oligopeptides; D010446:Peptide Fragments; D043562:Receptors, G-Protein-Coupled; D018027:Receptors, Glucagon; D011985:Receptors, Serotonin; D017868:Cyclic AMP-Dependent Protein Kinases; D000262:Adenylyl Cyclases