-
Proceedings of the National Academy of... Aug 2016The serine/threonine phosphatase protein phosphatase 5 (PP5) regulates hormone- and stress-induced cellular signaling by association with the molecular chaperone heat...
The serine/threonine phosphatase protein phosphatase 5 (PP5) regulates hormone- and stress-induced cellular signaling by association with the molecular chaperone heat shock protein 90 (Hsp90). PP5-mediated dephosphorylation of the cochaperone Cdc37 is essential for activation of Hsp90-dependent kinases. However, the details of this mechanism remain unknown. We determined the crystal structure of a Cdc37 phosphomimetic peptide bound to the catalytic domain of PP5. The structure reveals PP5 utilization of conserved elements of phosphoprotein phosphatase (PPP) structure to bind substrate and provides a template for many PPP-substrate interactions. Our data show that, despite a highly conserved structure, elements of substrate specificity are determined within the phosphatase catalytic domain itself. Structure-based mutations in vivo reveal that PP5-mediated dephosphorylation is required for kinase and steroid hormone receptor release from the chaperone complex. Finally, our data show that hyper- or hypoactivity of PP5 mutants increases Hsp90 binding to its inhibitor, suggesting a mechanism to enhance the efficacy of Hsp90 inhibitors by regulation of PP5 activity in tumors.
Topics: Catalytic Domain; Cell Cycle Proteins; Chaperonins; Crystallization; HSP90 Heat-Shock Proteins; Nuclear Proteins; Phosphoprotein Phosphatases; Phosphorylation; Substrate Specificity
PubMed: 27466404
DOI: 10.1073/pnas.1603059113 -
Methods in Enzymology 1982
Topics: Animals; Kidney; Kinetics; Molecular Weight; Phosphoprotein Phosphatases; Phosphorus Radioisotopes; Radioisotope Dilution Technique; Substrate Specificity; Swine
PubMed: 6296619
DOI: 10.1016/s0076-6879(82)90164-1 -
Enzymologia Jun 1957
Topics: Animals; Phosphoprotein Phosphatases; Phosphoric Monoester Hydrolases; Rats
PubMed: 13461836
DOI: No ID Found -
The Journal of Biological Chemistry Jan 1949
Topics: Animals; Breast; Mammals; Organogenesis; Phosphoprotein Phosphatases; Phosphoric Monoester Hydrolases
PubMed: 18123057
DOI: No ID Found -
Biochimica Et Biophysica Acta Apr 1954
Topics: Phosphoprotein Phosphatases; Phosphoric Monoester Hydrolases; Spleen
PubMed: 13160001
DOI: 10.1016/0006-3002(54)90380-7 -
European Journal of Biochemistry Oct 1981Phosphoprotein phosphatase IA, which represents the major glycogen synthase phosphatase activity in rat liver cytosol, has been purified to apparent homogeneity by...
Phosphoprotein phosphatase IA, which represents the major glycogen synthase phosphatase activity in rat liver cytosol, has been purified to apparent homogeneity by chromatography on DEAE-cellulose, histone - Sepharose-4B and Sephadex G-100. The molecular weight of the purified enzyme was 40 000 by gel filtration and 48 000 by sodium dodecyl sulfate gel electrophoresis, Phosphatase IA is therefore a monomeric protein. When treated with 80% ethanol at room temperature, phosphatase IA underwent an inactivation which was totally prevented by 2 mM MgCl2. Catalytically, phosphatase IA has a preference for glycogen synthase D compared with phosphatases IB and II and obligatorily requires Mg2+ or Mn2+ for activity. Maximum activity was attained at 5 mM MgCl2. Since Mg2+ does not activate other phosphoprotein phosphatases in rat liver cytosol, we propose the term 'Mg2+-dependent glycogen synthase phosphatase' for phosphatase IA.
Topics: Animals; Chromatography; Cytosol; Enzyme Activation; Glycogen-Synthase-D Phosphatase; Liver; Magnesium; Male; Phosphoprotein Phosphatases; Rats; Rats, Inbred Strains
PubMed: 6273162
DOI: 10.1111/j.1432-1033.1981.tb05636.x -
Nature Communications Jan 2015The cell division cycle requires tight coupling between protein phosphorylation and dephosphorylation. However, understanding the cell cycle roles of multimeric protein...
The cell division cycle requires tight coupling between protein phosphorylation and dephosphorylation. However, understanding the cell cycle roles of multimeric protein phosphatases has been limited by the lack of knowledge of how their diverse regulatory subunits target highly conserved catalytic subunits to their sites of action. Phosphoprotein phosphatase 4 (PP4) has been recently shown to participate in the regulation of cell cycle progression. We now find that the EVH1 domain of the regulatory subunit 3 of Drosophila PP4, Falafel (Flfl), directly interacts with the centromeric protein C (CENP-C). Unlike other EVH1 domains that interact with proline-rich ligands, the crystal structure of the Flfl amino-terminal EVH1 domain bound to a CENP-C peptide reveals a new target-recognition mode for the phosphatase subunit. We also show that binding of Flfl to CENP-C is required to bring PP4 activity to centromeres to maintain CENP-C and attached core kinetochore proteins at chromosomes during mitosis.
Topics: Animals; Animals, Genetically Modified; Cell Cycle; Cells, Cultured; Centromere; Chromosomal Proteins, Non-Histone; Crystallography; Drosophila Proteins; Drosophila melanogaster; Electrophoretic Mobility Shift Assay; Image Processing, Computer-Assisted; Mass Spectrometry; Microscopy, Confocal; Mutagenesis, Site-Directed; Phosphoprotein Phosphatases; Protein Structure, Tertiary; RNA Interference
PubMed: 25562660
DOI: 10.1038/ncomms6894 -
Structure (London, England : 1993) May 1999The recently determined crystal structure of the PR65/A subunit of protein phosphatase 2A reveals the architecture of proteins containing HEAT repeats. The structural... (Review)
Review
The recently determined crystal structure of the PR65/A subunit of protein phosphatase 2A reveals the architecture of proteins containing HEAT repeats. The structural properties of this solenoid protein explain many functional characteristics and account for the involvement of solenoids as scaffold, anchoring and adaptor proteins.
Topics: Phosphoprotein Phosphatases; Protein Conformation; Protein Phosphatase 2
PubMed: 10378263
DOI: 10.1016/s0969-2126(99)80060-4 -
The Biochemical Journal Jun 1962
Topics: Brain; Brain Chemistry; Phosphoprotein Phosphatases; Phosphoric Monoester Hydrolases
PubMed: 14493848
DOI: 10.1042/bj0830614 -
Plant Molecular Biology Dec 1998In the past few years, molecular cloning studies have revealed the primary structure of plant protein serine/threonine phosphatases. Two structurally distinct families,... (Review)
Review
In the past few years, molecular cloning studies have revealed the primary structure of plant protein serine/threonine phosphatases. Two structurally distinct families, the PP1/PP2A family and the PP2C family, are present in plants as well as in animals. This review will focus on the plant PP2C family of protein phosphatases. Biochemical and molecular genetic studies in Arabidopsis have identified PP2C enzymes as key players in plant signal transduction processes. For instance, the ABI1/ABI2 PP2Cs are central components in abscisic acid (ABA) signal transduction. Arabidopsis mutants containing a single amino acid exchange in ABI1 or ABI2 show a reduced response to ABA. Another member of the PP2C family, kinase-associated protein phosphatase (KAPP), appears to be an important element in some receptor-like kinase (RLK) signalling pathways. Finally, an alfalfa PP2C acts as a negative regulator of a plant mitogen-activated protein kinase (MAPK) pathway. Thus, the plant PP2Cs function as regulators of various signal transduction pathways.
Topics: Abscisic Acid; Amino Acid Sequence; Arabidopsis; Arabidopsis Proteins; Medicago sativa; Molecular Sequence Data; Phosphoprotein Phosphatases; Plants; Protein Phosphatase 2; Protein Phosphatase 2C; Saccharomyces cerevisiae Proteins; Sequence Alignment; Sequence Homology, Amino Acid; Signal Transduction
PubMed: 9869399
DOI: 10.1023/a:1006054607850