Relationships within the family of GTP-binding proteins isolated from bovine central nervous system.

摘要: Abstract Four members of a family GTP-binding proteins (G-proteins) which translate stimulation extracellular receptors into regulation intracellular enzymes were isolated from the bovine central nervous system. These examined for functional similarities and cross-reactivity with antibodies to G-protein (transducin, Gt) photoreceptor Two proteins, Gs Gi, can be distinguished by their respective abilities stimulate or inhibit adenylate cyclase. The activated alpha subunits Gt fourth member family, Go, did not affect this enzyme. was shown unique in its ability cGMP-dependent phosphodiesterase. While functionally diverse, G-proteins have some common antigenic properties. Antibodies directed against beta subunit recognize 36 all preparations but putative second 35 subunit. specific other when immune blots sodium dodecyl sulfate gels examined. However, Go alpha, Gi reacted strongly native spotted directly. This suggests that homologous structural determinants. An antiserum recognized gamma sources. data support proposed diversity function similarity structure among four G-proteins. potentially appear responsible specificity function.