Protein Domain : Serine/Threonine protein phosphatase PP2A-like IPR047129

Type	Family
Description	This entry represents PP2A-like family of phosphoprotein phosphatases (PPPs) which includes PP2A, PP4 and PP6, which are more closely related in sequence to one another than they are to the other PPPs [ ]. PP2A (Protein phosphatase 2A) is a critical regulator of many cellular activities, and together with protein phosphatase 1 (PP1), accounts for more than 90% of all serine/threonine phosphatase activities in most cells and tissues. The PP2A subunit has a catalytic domain homologous to PP1 and a unique C-terminal tail, containing a motif that is conserved in the catalytic subunits of all PP2A-like phosphatases including PP4 and PP6, and has an important role in PP2A regulation. The PP2A-like family of phosphatases all share a similar heterotrimeric architecture, that includes: a 65kDa scaffolding subunit (A), a 36kDa catalytic subunit (C), and one of 18 regulatory subunits (B). The PPP (phosphoprotein phosphatase) family, to which PP2A belongs, is one of two known protein phosphatase families specific for serine and threonine. PP2A is the major phosphatase for microtubule-associated proteins (MAPs) [].PP4 (also known as protein phosphatase X) is a phosphatase involved in many processes such as microtubule organization at centrosomes, maturation of spliceosomal snRNPs, apoptosis, DNA repair, tumour necrosis factor (TNF)-alpha signalling, activation of c-Jun N-terminal kinase MAPK8, regulation of histone acetylation, DNA damage checkpoint signalling, NF-kappa-B activation and cell migration. The PPP4C-PPP4R1 PP4 complex may play a role in dephosphorylation and regulation of HDAC3. The PPP4C-PPP4R2-PPP4R3A PP4 complex specifically dephosphorylates H2AX phosphorylated on Ser-140 (gamma-H2AX) generated during DNA replication and required for DNA double strand break repair [ , , ].PP6 is a component of a signaling pathway regulating cell cycle progression in response to IL2 receptor stimulation [ ]. It also regulates innate immunity by acting as a negative regulator of the cGAS-STING pathway as it mediates dephosphorylation and inactivation of CGAS and STING1 [, ].
Short Name	PPA2-like