Which of the following intracellular signal molecules regulates the catalysis of the conversion of GTP to cGMP?
A) cAMP
B) ceramide
C) diacylglycerol
D) inositol trisphosphate
E) nitric oxide

Question

Quizplus · Accepted Answer

Nitric oxide (NO) is a signaling molecule that activates guanylate cyclase, which catalyzes the conversion of GTP to cGMP.  Within smooth muscle cells, nitric oxide (NO) reacts with the heme moiety of a soluble guanylyl cyclase, resulting in activation of the latter and a consequent conversion of GTP to cGMP. The net effect is the activation of cGMP-dependent protein kinase (PKG) and the phosphorylation of substrates leading to smooth muscle cell relaxation.

Which of the Following Intracellular Signal Molecules Regulates the Catalysis