Written by the Fiveable Content Team • Last updated August 2025
Written by the Fiveable Content Team • Last updated August 2025
Definition
A protein kinase is an enzyme that modifies other proteins by chemically adding phosphate groups to them, a process known as phosphorylation. This action can change the activity, behavior, or location of the target protein within the cell.
The addition of a phosphate group to a molecule, such as a protein, altering its function and activity.
Enzyme: A biomolecule that acts as a catalyst to induce chemical changes in other substances without being changed itself.
Hormone Signaling: The process by which hormones communicate with cells, often involving activation or inhibition of protein kinases to elicit cellular responses