Question

please answer 1 a-f

1. Explain how G proteins are regulated. Include in your answer a description of the functions of GTP binding, GTP hydrolysis, and GDP exchange for GTP in terms of effector activation, as well as the functions of regulatory proteins GEFs, GAPs, and GDls. (12 points total, 2 points each) A. Function of GTP and GDP binding on G protein activity B. Impact of GTP/GDP on G protein binding to an effector C. Role of G protein's own enzymatic activity on signaling D. Role of GAPs in G protein signaling E. Role of GEFs in G protein signaling F. Role of GDls in G protein signaling

Answer 1

Question

A. Function of GTP is to activate the G  protein in G-protein signalling pathway. Function of GDP is to stop the G protein signaling pathway and formed when GTP hydrolysis take place.

B. When GTP is hydrolyzed with a water molecule it provide the energy that help the activation of G protein in GTP bound signalling pathway.

C. G protein act as molecular switch inside the cell and involved in transmitting signal inside the cell.

D. The function of the GAP is to increase the rate of GTP hydrolysis.

E. Guanine nucleotide exchange factor activate the G protein by exchanging the GDP bound to GTP.

F. GDI (guanine dissociation inhibitor) inhibit the conversion of GDP for GTP.