Two pathways exist in mammalian cells to degrade 1-phosphatidyl-1D-myo-inositol 4,5-bisphosphate [PtdIns(4,5)P2] . One is catalysed by this enzyme and the other by EC 3.1.3.36, phosphoinositide 5-phosphatase, where the product is PtdIns4P. The enzyme from human is specific for PtdIns(4,5)P2 as substrate, as it cannot use PtdIns(3,4,5)P3, PtdIns(3,4)P2, PtdIns(3,5)P2, PtdIns5P, PtdIns4P or PtdIns3P . In humans, the enzyme is localized to late endosomal/lysosomal membranes . It can control nuclear levels of PtdIns5P and thereby control p53-dependent apoptosis .
Specify your search results
The expected taxonomic range for this enzyme is: Eukaryota, Bacteria
IpgD, phosphatidylinositol-4,5-bisphosphate 4-phosphatase I, phosphatidylinositol-4,5-bisphosphate 4-phosphatase II, phosphoinositide phosphatase, PtdIns(4,5)P2 4-phosphatase, PtdIns-4,5-P2 4-phosphatase type I, PtdIns-4,5-P2 4-phosphatase type II, SigD, type I 4-phosphatase, type I phosphatidylinositol-4,5-bisphosphate 4-phosphatase, more
Two pathways exist in mammalian cells to degrade 1-phosphatidyl-1D-myo-inositol 4,5-bisphosphate [PtdIns(4,5)P2] [2]. One is catalysed by this enzyme and the other by EC 3.1.3.36, phosphoinositide 5-phosphatase, where the product is PtdIns4P. The enzyme from human is specific for PtdIns(4,5)P2 as substrate, as it cannot use PtdIns(3,4,5)P3, PtdIns(3,4)P2, PtdIns(3,5)P2, PtdIns5P, PtdIns4P or PtdIns3P [2]. In humans, the enzyme is localized to late endosomal/lysosomal membranes [2]. It can control nuclear levels of PtdIns5P and thereby control p53-dependent apoptosis [3].
evidence is provided that SigD functions as a 4â-phosphatase that dephosphorylates D-myo-phosphatidylinositol 4,5-bisphosphate to form D-myo-phosphatidylinositol 5-phosphate
siRNA of type I 4-phosphatase reduces type I 4-phosphatase levels, which is followed by a dramatic decrease in p53 levels in response to the genotoxic agent etoposide. siRNA of type II 4-phosphatase does not reduce p53 expression
10 microM concentration of inositol 1,4,5-trisphosphate and 1500 counts per minute of [3H]inositol 1,4,5-trisphosphate, recombinant GST-IpgD expressed with chaperone IpgE (1-3 microg), reaction 37°C for 10 min in a 50 microl final volume containing 50 mM HEPES pH 7.4, 0.1% bovine serum albumin, 2 mM MgCl2, and 0.033% b-mercaptoethanol, similar results when expressed without IpgE
50 microl of recombinant GST-IpgD expressed with chaperone IpgE (1-3 microg) in 50 mM Tris pH 7.5 containing 50 mM glutathione and 100 mM NaCl , 37°C, 15 min, reaction mixture contained 10 microM [32P] phosphatidylinositol 3-phosphate and 20 microM phosphatidylserine, similar results when expressed without IpgE
50 microl of recombinant GST-IpgD expressed with chaperone IpgE (1-3 microg) in 50 mM Tris pH 7.5 containing 50 mM glutathione and 100 mM NaCl , 37°C, 15 min, reaction mixture contained 10 microM [32P] phosphatidylinositol 4-phosphate and 20 microM phosphatidylserine, similar results when expressed without IpgE
50 microl of recombinant GST-IpgD expressed with chaperone IpgE (1-3 microg) in 50 mM Tris pH 7.5 containing 50 mM glutathione and 100 mM NaCl, 37°C, 15 min, reaction mixture contained 10 microM [32P] phosphatidylinositol 3,4-bisphosphate and 20 microM phosphatidylserine, similar results when expressed without IpgE
50 microl of recombinant GST-IpgD expressed with chaperone IpgE (1-3 microg) in 50 mM Tris pH 7.5 containing 50 mM glutathione and 100 mM NaCl, 37°C, 15 min, reaction mixture contained 10 microM [32P] phosphatidylinositol 3,4,5-trisphosphate and 20 microM phosphatidylserine, similar results when expressed without IpgE
50 microl of recombinant GST-IpgD expressed with chaperone IpgE (1-3 microg) in 50 mM Tris pH 7.5 containing 50 mM glutathione and 100 mM NaCl , 37°C, 15 min, reaction mixture contained 10 microM [32P] phosphatidylinositol 4,5-bisphosphate and 20 microM phosphatidylserine, similar results when expressed without IpgE
not detectable, 1 microM inositol 1,3,4,5-tetrakisphosphate and 1500 counts per minute of [3H]inositol 1,3,4,5-tetrakisphosphate, recombinant GST-IpgD expressed with chaperone IpgE (1-3 microg), reaction 37°C for 10 min in a 50 microl final volume containing 50 mM HEPES pH 7.4, 0.1% bovine serum albumin, 2 mM MgCl2, and 0.033% beta-mercaptoethanol
when HeLa cells are treated with etoposide or doxorubicin, type I 4-phosphatase translocates to the nucleus and nuclear levels of phosphatidylinositol 5-phosphate increase
PtdIns(4,5)P2 4-phosphatase expression induces Src kinase and Akt, but not ERK activation and enhances interleukin II promoter activity in T-cells. Expression of a PtdIns5P interacting domain, PH-Dok-5, blocks IpgD-induced T-cell activation and selective signaling molecules downstream of TCR triggering, evaluation, overview
phosphatidylinositol 5-phosphate may play a sensor function in setting the threshold of T-cell activation and contributing to maintain T-cell homeostasis
recombinant protein, Saccharomyces cerevisiae: strong impact on actin filaments and budding, HeLa (Green Fluorescent Protein linked): loss of adherence and strong impact on actin filaments
recombinant protein, Saccharomyces cerevisiae: strong impact on actin filaments and budding, HeLa (Green Fluorescent Protein linked): loss of adherence and strong impact on actin filaments
recombinant protein, Saccharomyces cerevisiae: strong impact on actin filaments and budding, residues 118â142 crucial for toxicity of SigD in the yeast cells, affecting both phosphatase activity and actin depolarization events, no effect (Green Fluorescent Protein linked) in HeLa
recombinant protein, Saccharomyces cerevisiae: strong impact on actin filaments and budding, HeLa (Green Fluorescent Protein linked): loss of adherence and strong impact on actin filaments
Please wait a moment until the data is sorted. This message will disappear when the data is sorted.
CLONED (Commentary)
ORGANISM
UNIPROT
LITERATURE
(PCR) amplification from the SigD open reading frame from S. enterica ser. typhimurium C53 genomic DNA. 2 types plasmids: first type based on the pEG-KG vector to express GST fusion proteins in yeast, second type based on pGEX-KG for expression of GST-fused proteins in bacteria. transformation of Escherichia coli DH5alpha cells (used for molceularbiological methods and expression). Transformation of Saccharomyces cerevisiae YPH499 (used for SigD functional analyzes as a model organism). transfection of human epithelial cell line HeLa (ATCC CCL2). yeast: endogenous SigD expression results in severe growth inhibition, allele mutant in catalytic site or deletion of whole C-terminal phosphatase domain inhibit growth by loss of actin polarization and precluding the budding process. HeLa: expression of same sigD alleles causes loss of ability of depleting phosphatidylinositol 4,5-bisphosphate from the plasma membrane, actin fibres still disappear and lose their adherence. region of 25 amino acids localized (residues 118â142) essentially required for the effect of SigD on actin in HeLa cells. SigD exerts a toxic effect linked to its N-terminal region and independent of its phosphatase activity
by cloning SigD into a mammalian expression vector, it is introduced into intact epithelia cells by microinjection: wild-type SigD induces striking morphological and functional changes that are not mimicked by a phosphatase-deficient SigD mutant C462S
infection assay: isotopic equilibrium of Shigella flexneri either wild-type strain M90T, ipgD mutant or the non-invasive strain BS176 (each expressing the AfaE adhesion). Green Fluorescent Protein-tagged IpgD recombinant protein (2 types: wild-type and C438S) cloned in pKN16, transfection of semi-confluent HeLa cells or NIH-3T3 cells. IpgD hydrolyses phosphatidylinositol 4,5-bisphosphate during infection of epithelial cells by Shigella flexneri (analysis of phospholipid content of cells labelled with 32P), phosphatidylinositol 5-phosphate is the product of IpgD-dependent phosphatidylinositol 4,5-bisphosphate degradation in Shigella flexneri infected cells (HPLC, mass assay, immunofluorescence), cellular phosphatidylinositol 4,5-bisphosphate is the only phosphoinositide hydrolysed in vivo, IpgD causes membrane blebbing and cell rounding when expressed in HeLa cells (transiently expressed myc-tagged IpgD in HeLa cells, SDS-PAGE, antibodies against tag or protein), IpgD decreases cytoskeletal-membrane adhesion when expressed in NIH-3T3 cells (optical tweezers)
Salmonella typhimurium SL1344 wild-type and deltaSigD mutant lacking SigD. Transfection of COS-7 and HeLa cells with SigD in mammalian expression vectors. Visualization of phosphatidylinositol 4,5-bisphosphate during Salmonella infection. Fusion protein of PH domain of phospholipase Cdelta and GFP (PLCdelta-PH-GFP) during invasion of HeLA cells by Salmonella (confocal fluorescence microscopy): phosphatidylinositol 4,5-bisphosphate is abundant near the tip but disappears from the basal regions. Role of SigD in phosphatidylinositol 4,5-bisphosphate elimination: focal disappearance of phosphatidylinositol 4,5-bisphosphate observed during invasion (wild-type) is diminished and delayed in the deltaSigD mutant (confocal fluorescence microscopy). SigD alters memebrane elasticity (atomic force microscopy, SigD transfected HeLa cells) and induces vacuole formation. SigD promotes membrane fission during invasion (SigD transfected HeLa cells)
type I isozyme, DNA and amino acid sequence determination and analysis, transient transfection of functional enzyme to HeLa and COS-7 cells leading to increased EGFR degradation via increased phosphatidylinositol-5-phosphate content, functional overexpression of FLAG-tagged enzyme in Spodoptera frugiperda Sf9 cells using the baculovirus infection system, stable inducible expression of labeled isozyme I in HEK293 cells
type II isozyme, DNA and amino acid sequence determination and analysis, transient transfection of functional enzyme to HeLa and COS-7 cells leading to increased EGFR degradation via increased phosphatidylinositol-5-phosphate content, functional overexpression of FLAG-tagged enzyme in Spodoptera frugiperda Sf9 cells using the baculovirus infection system
type I 4-phosphatase regulates nuclear phosphatidylinositol 5-phosphate levels, which in turn mediate p53-dependent apoptosis through interaction with inhibitor of growth protein-2 in response to genotoxic stress