ROLE OF HETEROTRIMERIC GTP-BINDING PROTEINS IN VESICULAR PROTEIN-TRANSPORT - INDICATIONS FOR BOTH CLASSICAL AND ALTERNATIVE G-PROTEIN CYCLES

Heterotrimeric G proteins are involved in hormonal signal transduction across the plasma membrane. Recent evidence suggests that they have a role in vesicular protein transport as well, Biochemical probes that interfere with the classical G protein cycle have been applied to the field of intracellular membrane transport to study their mechanism of action. Evidence has been obtained that intracellular G proteins act both through classical and alternative G protein cycles.