Interaction of myelin basic protein with the different components of the ATP, Mg‐dependent protein phosphatase system

Abstract
Myelin basic protein (MBP) reduces the amount of phosphatase activity produced in the kinase FA‐mediated activation of the ATP,Mg‐dependent phosphatase. MBP was shown not only to inhibit the activated enzyme, but also to impair the kinase FA‐mediated activation of the inactive phosphatase. In addition MBP prevents the time‐dependent inactivation of the catalytic subunit by the modulator protein. These observations point to a regulatory role for MBP in the reversible activation of the ATP, Mg‐dependent protein phosphatase by kinase FA.