A Calmodulin-Regulated Kinase (CaM-Kinase) Is Involved in Spatial Learning and Memory.This

Essay

A calmodulin-regulated kinase (CaM-kinase) is involved in spatial learning and memory.This kinase is able to phosphorylate itself such that its kinase activity is now independent of the intracellular concentration of Ca²⁺.Thus, the kinase stays active after Ca²⁺ levels have dropped.Mice completely lacking this CaM-kinase have severe spatial learning defects but are otherwise normal.
A.Each of the following mutations also leads to similar learning defects.For each case explain why.
(1) a mutation that prevents the kinase from binding ATP
(2) a mutation that deletes the calmodulin-binding part of the kinase
(3) a mutation that destroys the site of autophosphorylation
B.What would be the effect on the activity of CaM-kinase if there were a mutation that reduced its interaction with the protein phosphatase responsible for inactivating the kinase?