Abstract

The regulatory component (G/F) of adenylate cyclase has been purified from turkey erythrocyte plasma membranes by adaptation of procedures developed for purification of the rabbit liver protein. The major modifications entail inclusion of high concentrations of NaCl to facilitate extraction and reconstitution of the protein. A typical preparation yields 200 micrograms of protein with a reconstitutive specific activity of 3-4 mumol . min-1 mg-1. Turkey erythrocyte G/F contains two putative subunits of 35,000 and 45,000 daltons. The 52,000-dalton polypeptide that appears to be a component of rabbit liver G/F is lacking. In solution, G/F behaves as a particle with Mr = 81,000. This value is reduced to 50,000 in the presence of activating ligands, suggesting dissociation of subunits. Activation of G/F by guanine nucleotide analogs is markedly accelerated in the presence of high concentrations of Mg2+. Reconstitutive and physical properties of the protein are also affected by fluoride. Cyc- S49 lymphoma membranes reconstituted with turkey erythrocyte G/F acquire properties that are characteristic of the turkey adenylate cyclase system; at least certain differing characteristics of adenylate cyclase systems are thus dictated by the nature of their G/F.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.