Differential effects of GTP on the coupling of beta-adrenergic receptors to adenylate cyclase from frog and turkey erythrocytes. Application of new methods for the analysis of receptor-effector coupling.

Published

Journal Article

A detailed comparison of the interaction of beta-adrenergic receptors with adenylate cyclase stimulation and modification of this interaction by guanine nucleotides has been made in two model systems, the frog and turkey erythrocyte. Objective analysis of the data was facilitated by the development of new graphical methods which involve the use of logit-logit transformations of percent receptor occupancy versus percent enzyme stimulation plots (coupling curves). Receptor-cyclase coupling in turkey erythrocyte membranes demonstrates a proportional relationship between receptor occupancy and adenylate cyclase activation and is unaffected by exogenous guanine nucleotides. By comparison, the proportional relationship of receptor occupancy and adenylate cyclase activation observed in frog erythrocyte membranes in the absence of guanine nucleotides is modified by the addition of exogenous guanine nucleotides such that a greater fractional enzyme stimulation is elicited by low receptor occupancy. Methodological criteria crucial for valid comparison of receptor occupancy and adenylate cyclase activity are delineated. In addition, the possible molecular mechanisms of receptor-cyclase coupling which might give rise to the coupling curves observed are discussed.

Full Text

Duke Authors

Cited Authors

  • Limbird, LE; DeLean, A; Hickey, AR; Pike, LJ; Lefkowitz, RJ

Published Date

  • August 22, 1979

Published In

Volume / Issue

  • 586 / 2

Start / End Page

  • 298 - 314

PubMed ID

  • 224939

Pubmed Central ID

  • 224939

International Standard Serial Number (ISSN)

  • 0006-3002

Digital Object Identifier (DOI)

  • 10.1016/0304-4165(79)90101-6

Language

  • eng

Conference Location

  • Netherlands