Question

1. Discuss the function of an active adenylate cyclase and the mechanism of generation of cAMP:

Answer 1

Adenylate cyclase also known as Adenyl cyclase.It is an enzyme which convert ATP into cAMP(cyclic adenosine monophosphate) and pyrophosphate.This conversion inturn increase the intracellular level of cyclic AMP which is used for different functions.

Mechanism of generation of cAMP-

There are many hormones which utilize the second messenger system that is Cyclic AMP(cAMP) like Epinephrine,LH,FSH,glucagon etc.

Let's understand its mechanism with the help of a hormone like Epinephrine.

Step 1-Epinephrine is the first messenger which binds with a surface receptor.This receptor have a peripheral G protein on its inner side.

Step2-Once receptor is activated by the Epinephrine,then G protein is activated.

Step3-The alpha subunit of activated G protein now detach itself from beta and gamma subunit and activate another enzyme called Adenyl cyclase.

Step4-This enzyme convert ATP into cAMP by removing 2 phosphate groups

Step5- This cAMP(second messenger) now activates another cytoplasmic enzymes called Kinases.

Step6-This kinase now phosphorylate other enzymes which perform metavolic function and the cycle goes on like this