Question

The regulators of G protein signalling (RGS) family of proteins are becoming increasingly important in the study of the mechanisms of disease development and represent potential targets for drug development. Which of the RGS protein subgroups acts through early termination of alpha subunit signalling rather than changing the ease with which the alpha subunit is activated?

Select one:

a. GAPs

b. GEFs

c. GDIs

d. Rho GTPases

Answer 1

Answer: a. GAPs. The RGS protein subgroups that acts through early termination of alpha subunit signalling rather than changing the ease with which the alpha subunit is activated are GAPs or GTPase activating proteins. GAPs play a key role in regulating the activity of G proteins. They are also called as RGS proteins. GAPs are regulatory proteins. Their role in G protein signalling pathway is to bind to the activated alpha subunit of the G protein and stimulate its GTPase activity leading to GTP replaced with GDP, inactivating the alpha subunit eventually. Thus the role of GAPs in G protein signalling pathway is to turn it off.