PP2A: Proteins and Enzymes

Protein Phosphatase 2A (PP2A) is an enzyme that removes phosphates covalently attached to serine and threonine residues in proteins. It contains three subunits; a catalytic subunit C (PP2Ac), an assembly/structural subunit A (PP2Aa), and a regulatory subunit B (PP2Ab). PP2A is a ubiquitous enzyme that plays a role in regulating many cellular activities varying from ion transport in erythrocytes to suppressing tumor growth. Binding of the SV40 small T antigen to the PP2A phosphatase complex is known to cause oncogenic transformation.