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.