PDXP
PDXP (pyridoxal phosphatase), also known as chronophin or CIN, is a HAD-family phosphatase that dephosphorylates the vitamin B6 cofactor pyridoxal 5'-phosphate. It also acts as a protein serine phosphatase on cofilin, linking vitamin B6 metabolism to actin dynamics. Browse Assay Genie's current range of PDXP research reagents below, or read on for the biology behind the target.
PDXP functions as a pyridoxal phosphate (PLP) phosphatase. It also catalyses the dephosphorylation of pyridoxine 5'-phosphate (PNP) and pyridoxamine 5'-phosphate (PMP), with a substrate preference of PLP over PNP over PMP, and so plays a role in vitamin B6 metabolism. PLP is the active form of vitamin B6 and acts as a coenzyme in maintaining biochemical homeostasis. The preferred route of degradation from PLP to 4-pyridoxic acid involves dephosphorylation of PLP by PDXP.
The enzyme has a second, distinct activity as a protein serine phosphatase. It specifically dephosphorylates Ser-3 in members of the actin-depolymerising factor (ADF)/cofilin family, such as CFL1 and DSTN. Through this activity PDXP regulates cofilin-dependent reorganisation of the actin cytoskeleton and is required for normal progress through mitosis and normal cytokinesis. It does not dephosphorylate phosphothreonines in LIMK1, and it does not act on peptides containing phosphotyrosine.
The PDXP gene encodes a protein that belongs to the HAD-like hydrolase superfamily and is classed by HGNC in the HAD Asp-based protein phosphatases. UniProt records the protein name chronophin, and the gene has also been listed as dJ37E16.5, FLJ32703 and CIN. Its previous HGNC name was pyridoxal (pyridoxine, vitamin B6) phosphatase. The protein is found in the cytosol and cytoskeleton, and at the cell membrane, including ruffle and lamellipodium membranes. Mouse and rat both have a Pdxp ortholog.
PDXP dephosphorylates PLP, PNP and PMP, and the dephosphorylation of PLP is the preferred route towards 4-pyridoxic acid.
By removing phosphate from Ser-3 of cofilin family proteins, PDXP regulates cofilin-dependent actin cytoskeleton reorganisation.
PDXP is required for normal progress through mitosis and normal cytokinesis, making it relevant to cell division studies.
PDXP acts on both small-molecule phosphates and phosphoserine in proteins, but not phosphotyrosine peptides or LIMK1 phosphothreonines.
PDXP dephosphorylates pyridoxal 5'-phosphate, the active form of vitamin B6, and also acts on pyridoxine 5'-phosphate and pyridoxamine 5'-phosphate. It additionally removes phosphate from Ser-3 of cofilin family proteins, regulating actin cytoskeleton reorganisation, mitosis and cytokinesis.
The protein is called chronophin in UniProt, and the gene has the aliases CIN, dJ37E16.5 and FLJ32703. HGNC previously named it pyridoxal (pyridoxine, vitamin B6) phosphatase. It carries two EC numbers, 3.1.3.16 and 3.1.3.74, reflecting its protein and PLP phosphatase activities.
Yes. Mouse and rat each have an ortholog named Pdxp. The human protein belongs to the HAD-like hydrolase superfamily. Check the datasheet of any product for its validated reactivity.
Cofilin family substrates, actin regulators and other phosphatases relevant to cytoskeleton and vitamin B6 research.
Gene and protein annotations from HGNC, NCBI Gene and UniProt Q96GD0; product specifications from Assay Genie datasheets.