Question

1. Under resting conditions, the basal rate of degradation of a small signaling mediator, such as cAMP, is relatively high. Why might this be important for cAMP-dependent signaling?

2. Describe two different ways that, in principle, an incoming signal could result in an increase in cAMP levels in a cell.

Answer 1

1. Phophodiestarase is responsible for cAMP degradation. The high rate of degradation will help cAMP to get eliminated in the absence of input signal.

2. there are two different ways by which an incoming signal can result in an increase in cAMP levels-

a. incoming signal might incease the activity of adenyl cyclase. Adenyl cyclase is producing cAMP from ATP

b. incoming signal might decrease phosphodiesterase activity, thereby reducing the rate of cAMP to AMP formation.