Question

Many second messenger systems activate ________, enzymes that transfer a phosphate group from ATP to a protein. The phosphorylation of proteins sets off a series of intracellular events that lead to the ultimate cellular response

Answer 1

Many second messenger systems activate kinases, enzymes that transfer a phosphate group from ATP to a protein. The phosphorylation of proteins sets off a series of intracellular events that lead to the ultimate cellular response.

Step-by-step explanation:

For example, the second messenger cAMP activates the protein kinase A (PKA), which catalyzes the phosphorylation of other proteins.

The second messenger Ca²⁺ forms an active complex with a protein called calmodulin. This complex activates CaM kinases, that phosphorylate a group of target proteins, regulating its activities.