PPase_methylesterase_euk

Family: PPase_methylesterase_euk

Block: X

Parent Family: Abhydrolase_6

Comment

PIRSF022950 This group represents protein phosphatase methylesterase, eukaryotic type. Carboxymethylation of proteins is a highly conserved means of regulation in eukaryotic cells. The protein phosphatase 2A (PP2A) catalytic (C) subunit is reversibly methylated at its carboxyl terminus by specific methyltransferase and methylesterase enzymes. Protein phosphatase 2A (PP2A) is an important serine/threonine phosphatase that plays a role in many biological processes. Reversible carboxyl methylation of the PP2A catalytic subunit is an essential regulatory mechanism for its function. Demethylation and negative regulation of PP2A is mediated by a PP2A-specific methylesterase PME-1, which is conserved from yeast to humans. PME-1 directly binds to the active site of PP2A. This interaction results in the activation of PME-1 by rearranging the catalytic triad into an active conformation. Interactions also lead to inactivation of PP2A by evicting the manganese ions required for the phosphatase activity (Xing et al. ). PPME proteins show false positive hits with the prosite PS00120 of lipases