Protein Phosphatase 4, Catalytic Subunit (PPP4C)

Protein phosphatases are involved in determining the phosphorylation state of many regulatory proteins. Other members of this family include PP1 , PP2A, and PP5 .

HDAC3 copurified with PPP4C and its regulatory subunit, PPP4R1, in an HDAC3 complex that showed phosphatase activity. Both PP4 proteins interacted directly with HDAC3, and mutation analysis indicated that the N terminus of HDAC3 was necessary and sufficient for HDAC3-PPP4C interaction. Both overexpression and RNA interference experiments indicated that HDAC3 activity was inversely proportional to the cellular abundance of PPP4C.