Structural highlights
Function
[PTPM1_MOUSE] Lipid phosphatase which dephosphorylates phosphatidylglycerophosphate (PGP) to phosphatidylglycerol (PG). PGP is an essential intermediate in the biosynthetic pathway of cardiolipin, a mitochondrial-specific phospholipid regulating the membrane integrity and activities of the organelle. Has also been shown to display phosphatase activity toward phosphoprotein substrates, specifically mediates dephosphorylation of mitochondrial proteins, thereby playing an essential role in ATP production. Has probably a preference for proteins phosphorylated on Ser and/or Thr residues compared to proteins phosphorylated on Tyr residues. Probably involved in regulation of insulin secretion in pancreatic beta cells (By similarity).
Publication Abstract from PubMed
PTPMT1 (PTP localized to the Mitochondrion 1) is a member of the protein tyrosine phosphatase superfamily that is localized exclusively to the mitochondrion. We recently reported that PTPMT1 dephosphorylates phosphatidylglycerol phosphate, an essential intermediate of cardiolipin biosynthesis. To gain further insights into the molecular basis of PTPMT1 function, we determined the crystal structures of the phosphatase domain of PTPMT1. PTPMT1 exhibits a canonical protein tyrosine phosphatase domain fold, resembling many dual-specificity phosphatases such as phosphatase and tensin homolog and vaccinia H1-related phosphatase. We also determined the structure of the catalytically inactive phosphatase in complex with a surrogate substrate, phosphatidylinositol 5-phosphate, which sheds light on the substrate recognition and specificity of PTPMT1. Comparison of the apo and substrate-bound structures of PTPMT1 suggests that it undergoes significant conformational change during catalysis, and we further demonstrated that an evolutionarily conserved EEYE loop is important for its activity.
Structural and functional analysis of PTPMT1, a phosphatase required for cardiolipin synthesis.,Xiao J, Engel JL, Zhang J, Chen MJ, Manning G, Dixon JE Proc Natl Acad Sci U S A. 2011 Jul 5. PMID:21730175[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Xiao J, Engel JL, Zhang J, Chen MJ, Manning G, Dixon JE. Structural and functional analysis of PTPMT1, a phosphatase required for cardiolipin synthesis. Proc Natl Acad Sci U S A. 2011 Jul 5. PMID:21730175 doi:10.1073/pnas.1109290108
