Question

How do mitogen-activated protein (MAP) kinases become inactive?

Please choose the correct answer from the following choices, and then select the submit answer button.


-Phosphatases remove phosphate groups.

-Ligand diffuses away from the ligand-binding site.

-Receptor kinases move apart in the membrane.

-Ras hydrolyzes GTP to GDP.

Answer 1

MAP kinases are inactivated by phosphatases, which remove phosphate groups in a process called dephosphorylation, reversing the kinase's active state.

Step-by-step explanation:

Mitogen-activated protein (MAP) kinases become inactive through the action of enzymes called phosphatases, which remove phosphate groups from the kinases. This process is known as dephosphorylation. When the phosphate groups are removed, the conformation of the MAP kinases changes back to an inactive state, thus stopping their ability to signal cellular responses, such as cell division and differentiation. The Ras protein plays a central role in many receptor kinase signaling pathways and is known to activate the MAP kinase pathway. However, when Ras hydrolyzes GTP to GDP, this leads to the deactivation of the MAP kinase signaling pathway. The GTP hydrolysis is an example of turning off the signal transduction, but it is specifically the phosphatase activity that directly inactivates MAP kinases.

MAP (mitogen-activated protein) kinases become inactive when phosphatases remove phosphate groups from them. Phosphatases are enzymes that catalyze the dephosphorylation of proteins, reversing the phosphorylation process. In the case of MAP kinases, phosphatases remove the phosphate group attached to the kinase, leading to its inactivation.