Isolation of homologous and heterologous complexes between catalytic and regulatory components of adenylate cyclase by forskolin—Speharose

Abstract

Homologous and heterologous complexes between catalytic and GTP-binding components can be isolated by means of immobilized succinyldeacetylforskolin (forskolin—Sepharose). A heterologous complex is formed by reconstitution of forskolin—Sepharose bound catalytic function from rabbit myocardial membranes with the homogeneous [³H]methyl-GTP-binding protein from duck erythrocyte membranes. Analysis of the reconstituted complex by sodium dodecyl sulfate polyacrylamide gelelectrophoresis reveals that only the M _r 42 000 component of the GTP-binding protein's M _r 42 000/M _r 35 000 heterodimer contributes to the formation of active adenylate cyclase.