127k views
0 votes
Using epinephrine as an example, explain how nonsteroid hormones act via second messengers, including the roles of adenylate cyclase, cyclic AMP, G proteins and cAMP dependent protein kinase.

1 Answer

2 votes

Final answer:

Epinephrine, a nonsteroid hormone, utilizes cAMP as a second messenger to activate cellular responses through the activation of G-proteins, adenylate cyclase, and cAMP-dependent protein kinase.

Step-by-step explanation:

Cyclic adenosine monophosphate (cAMP) is a second messenger used by nonsteroid hormones like epinephrine.

When epinephrine binds to its receptor on the cell membrane, it activates a G-protein, which in turn activates adenylate cyclase (also known as adenylyl cyclase).

Adenylate cyclase converts adenosine triphosphate (ATP) to cAMP. cAMP acts as the second messenger and activates a protein kinase called cAMP-dependent protein kinase (PKA).

This PKA initiates a phosphorylation cascade, where multiple protein kinases phosphorylate various cellular proteins.

This phosphorylation can activate or inhibit certain enzymes and metabolic pathways in the cell, leading to a cell-specific response.

Overall, nonsteroid hormones like epinephrine use second messengers like cAMP and cAMP-dependent protein kinase to transmit signals and regulate cellular processes.

User Jay Shin
by
8.2k points
Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.