title: Identification of a filamin docking site on PTP-PEST.
abstract: PTP-PEST is a cytoplasmic protein-tyrosine phosphatase (PTP) implicated in the regulation of biological processes such as cell motility, cytokinesis, focal adhesion disassembly, and lymphocyte activation. Using a proteomics approach, filamin-A was identified as a novel interacting protein that bound to GST-PTP-PEST. This interaction was confirmed in vitro and in cells by coimmunoprecipitation. The site of filamin interaction on PTP-PEST was mapped to the fourth proline-rich region (Pro4). PTP-PEST has previously been implicated in the regulation of cytokinesis. In further support of this finding, expression of PTP-PEST in HeLa cells resulted in the formation of multinucleated cells. A PTP-PEST mutant lacking Pro4 and unable to bind filamin-A failed to induce the multinucleated phenotype. Further, depletion of filamin-A in HeLa cells was found to reduce the PTP-PEST-dependent multinucleation phenotype. Hence, we conclude that the interaction of PTP-PEST with filamin-A may function in the control of cytokinesis in mammalian cells.
authors.affiliation: Department of Cell and Developmental Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA.
authors.forename: Martin P
authors.initials: MP
authors.lastname: Playford
authors.forename: Patrick D
authors.initials: PD
authors.lastname: Lyons
authors.forename: Sarita K
authors.initials: SK
authors.lastname: Sastry
authors.forename: Michael D
authors.initials: MD
authors.lastname: Schaller
mesh_terms: D001665:Binding Sites; D015153:Blotting, Western; D002467:Cell Nucleus / Q000648:ultrastructure; D002478:Cells, Cultured; D003285:Contractile Proteins / Q000378:metabolism*; D048749:Cytokinesis; D064448:Filamins; D005434:Flow Cytometry; D005982:Glutathione Transferase / Q000235:genetics / Q000378:metabolism; D006801:Humans; D007668:Kidney / Q000166:cytology / Q000378:metabolism; D008840:Microfilament Proteins / Q000378:metabolism*; D008856:Microscopy, Fluorescence; D010641:Phenotype; D011485:Protein Binding; D054594:Protein Tyrosine Phosphatase, Non-Receptor Type 12; D017027:Protein Tyrosine Phosphatases / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D003285:Contractile Proteins; D064448:Filamins; D008840:Microfilament Proteins; D011993:Recombinant Fusion Proteins; D005982:Glutathione Transferase; C516738:PTPN12 protein, human; D054594:Protein Tyrosine Phosphatase, Non-Receptor Type 12; D017027:Protein Tyrosine Phosphatases