Antisera of designed specificity for subunits of guanine nucleotide-binding regulatory proteins.

Antisera were raised against purified subunits of regulatory GTP-binding proteins (G proteins) and against synthetic peptides that correspond to defined regions of G proteins. Peptide antisera were generated that recognized all alpha or all beta subunits from Gs, Gi, Go, and transducin; others recognized only Gs alpha or Go alpha. Such cross-reaction or complete specificity for a given alpha subunit was not obtained when purified subunits were injected. Peptide antisera were used to identify G protein subunits in selected tissue membrane preparations by immunoblots.