The tryptic and chymotryptic fragments of the β‐subunit of guanine nucleotide binding proteins in brain are identical to those of retinal transducin

Publisher Website
Google Scholar
Abstract
The 35‐kDa β‐subunit of transducin purified from rod outer segment membranes is cleaved into 2 major fragments by trypsin, and 7 major fragments by chymotrypsin. Identical fragments are visualized by immunoblotting with transducin‐β specific antisera after proteolysis of rod outer segment membranes, purified brain guanine nucleotide binding proteins, and brain membranes. The results indicate that the β‐subunits of transducin and of brain guanine nucleotide binding proteins are not only similar structurally, but are also similarly oriented in membranes with respect to accessibility to proteolytic enzymes.