Publication Date:
1993-07-09
Description:
Evidence suggests that both alpha and beta gamma subunits of heterotrimeric guanine nucleotide-binding regulatory proteins (G proteins) inhibit adenylyl cyclase. Although type I adenylyl cyclase is inhibited directly by exogenous beta gamma, inhibition of adenylyl cyclase by Gi alpha has not been convincingly demonstrated in vitro. Concentration-dependent inhibition of adenylyl cyclases by purified Gi alpha subunits is described. Activated Gi alpha but not G(o) alpha was effective, and myristoylation of Gi alpha was required. The characteristics of the inhibitory effect were dependent on the type of adenylyl cyclase and the nature of the activator of the enzyme. The concentrations of Gi alpha required to inhibit adenylyl cyclase were substantially higher than those normally thought to be relevant physiologically. However, analysis indicates that these concentrations may be relevant and reasonable.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Taussig, R -- Iniguez-Lluhi, J A -- Gilman, A G -- GM34497/GM/NIGMS NIH HHS/ -- New York, N.Y. -- Science. 1993 Jul 9;261(5118):218-21.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas 75235-9041.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/8327893" target="_blank"〉PubMed〈/a〉
Keywords:
*Adenylyl Cyclase Inhibitors
;
Adenylyl Cyclases/metabolism
;
Animals
;
Calmodulin/pharmacology
;
Cell Line
;
Colforsin/pharmacology
;
Dose-Response Relationship, Drug
;
Enzyme Activation
;
GTP-Binding Proteins/*metabolism
;
Guanosine 5'-O-(3-Thiotriphosphate)/pharmacology
;
Guanosine Triphosphate/metabolism
;
Moths
;
Myristic Acid
;
Myristic Acids/metabolism
;
Recombinant Proteins/pharmacology
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
