Where Are Proteins Phosphorylated?

While phosphorylation is a prevalent post-translational modification (PTM) for regulating protein function, it only occurs at the side chains of three amino acids, serine, threonine and tyrosine, in eukaryotic cells.

How are proteins phosphorylated?

Protein phosphorylation is a reversible post-translational modification of proteins in which an amino acid residue is phosphorylated by a protein kinase by the addition of a covalently bound phosphate group. ... The reverse reaction of phosphorylation is called dephosphorylation, and is catalyzed by protein phosphatases.

Which protein is involved in phosphorylation?

Protein kinases

The protein kinases belong to the great family of kinases and are responsible for the mechanism of phosphorylation. They are activated by phosphorylation which in turn activates a cascade of events leading to the phosphorylation of different amino acids (3).