Question

Define a protein kinase and explain its role in a signal transduction pathway. Then describe what can happen if an organism's cells experience abnormal protein kinase activity.

Answer 1

Protein kinases add phosphate to other proteins, altering the activity of the phosphorylated proteins as part of cell signal transduction. In many pathway there is a phosphorylation cascade in which a series of protein kinases are phosphorylated along a chain.