Description: Homo sapiens protein phosphatase 1, catalytic subunit, beta isozyme (PPP1CB), transcript variant 3, mRNA. RefSeq Summary (NM_206876): The protein encoded by this gene is one of the three catalytic subunits of protein phosphatase 1 (PP1). PP1 is a serine/threonine specific protein phosphatase known to be involved in the regulation of a variety of cellular processes, such as cell division, glycogen metabolism, muscle contractility, protein synthesis, and HIV-1 viral transcription. Mouse studies suggest that PP1 functions as a suppressor of learning and memory. Two alternatively spliced transcript variants encoding distinct isoforms have been observed. [provided by RefSeq, Jul 2008]. Transcript (Including UTRs) Position: hg19 chr2:28,974,614-29,025,806 Size: 51,193 Total Exon Count: 9 Strand: + Coding Region Position: hg19 chr2:28,974,991-29,022,169 Size: 47,179 Coding Exon Count: 8
ID:PP1B_HUMAN DESCRIPTION: RecName: Full=Serine/threonine-protein phosphatase PP1-beta catalytic subunit; Short=PP-1B; Short=PPP1CD; EC=3.1.3.16; EC=3.1.3.53; FUNCTION: Protein phosphatase that associates with over 200 regulatory proteins to form highly specific holoenzymes which dephosphorylate hundreds of biological targets. Protein phosphatase (PP1) is essential for cell division, it participates in the regulation of glycogen metabolism, muscle contractility and protein synthesis. Involved in regulation of ionic conductances and long-term synaptic plasticity. Component of the PTW/PP1 phosphatase complex, which plays a role in the control of chromatin structure and cell cycle progression during the transition from mitosis into interphase. CATALYTIC ACTIVITY: A phosphoprotein + H(2)O = a protein + phosphate. CATALYTIC ACTIVITY: [Myosin light-chain] phosphate + H(2)O = [myosin light-chain] + phosphate. COFACTOR: Binds 1 iron ion per subunit (By similarity). COFACTOR: Binds 1 manganese ion per subunit (By similarity). ENZYME REGULATION: Inhibited by the toxins okadaic acid, tautomycin and microcystin Leu-Arg (By similarity). The phosphatase activity of the PPP1R15A-PP1 complex toward EIF2S1 is specifically inhibited by Salubrinal, a drug that protects cells from endoplasmic reticulum stress. SUBUNIT: PP1 comprises a catalytic subunit, PPP1CA, PPP1CB or PPP1CC, which is folded into its native form by inhibitor 2 and glycogen synthetase kinase 3, and then complexed to one or several targeting or regulatory subunits. The targeting or regulatory subunits determine the substrate specificity of PP1. PPP1R12A, PPP1R12B and PPP1R12C mediate binding to myosin. PPP1R3A (in skeletal muscle), PPP1R3B (in liver), PPP1R3C, PPP1R3D and PPP1R3F (in brain) mediate binding to glycogen. Part of a complex containing PPP1R15B, PP1 and NCK1/2 (By similarity). Component of the MLL5-L complex, at least composed of MLL5, STK38, PPP1CA, PPP1CB, PPP1CC, HCFC1, ACTB and OGT. Interacts with PPP1R7 and PPP1R12C. PPP1R15A and PPP1R15B mediate binding to EIF2S1. Interacts with PPP1R16B. Component of the PTW/PP1 phosphatase complex, composed of PPP1R10/PNUTS, TOX4, WDR82, and PPP1CA or PPP1CB or PPP1CC. Interacts with PPP1R8. Interacts with TRIM28; the interaction is weak. Interacts with PPP1R12A and NUAK1; the interaction is direct. INTERACTION: P38398:BRCA1; NbExp=3; IntAct=EBI-352350, EBI-349905; SUBCELLULAR LOCATION: Cytoplasm. Nucleus. Nucleus, nucleoplasm. Nucleus, nucleolus. Note=Highly mobile in cells and can be relocalized through interaction with targeting subunits. In the presence of PPP1R8 relocalizes from the nucleus to nuclear speckles. SIMILARITY: Belongs to the PPP phosphatase family. PP-1 subfamily. WEB RESOURCE: Name=Protein Spotlight; Note=The things we forget - Issue 32 of March 2003; URL="http://web.expasy.org/spotlight/back_issues/sptlt032.shtml";
The RNAfold program from the Vienna RNA Package is used to perform the secondary structure predictions and folding calculations. The estimated folding energy is in kcal/mol. The more negative the energy, the more secondary structure the RNA is likely to have.
ModBase Predicted Comparative 3D Structure on P62140
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Orthologous Genes in Other Species
Orthologies between human, mouse, and rat are computed by taking the best BLASTP hit, and filtering out non-syntenic hits. For more distant species reciprocal-best BLASTP hits are used. Note that the absence of an ortholog in the table below may reflect incomplete annotations in the other species rather than a true absence of the orthologous gene.
Gene Ontology (GO) Annotations with Structured Vocabulary
Molecular Function: GO:0004721 phosphoprotein phosphatase activity GO:0004722 protein serine/threonine phosphatase activity GO:0005515 protein binding GO:0016787 hydrolase activity GO:0016791 phosphatase activity GO:0017018 myosin phosphatase activity GO:0019901 protein kinase binding GO:0046872 metal ion binding GO:0050115 myosin-light-chain-phosphatase activity
Biological Process: GO:0005975 carbohydrate metabolic process GO:0005977 glycogen metabolic process GO:0006470 protein dephosphorylation GO:0007049 cell cycle GO:0030155 regulation of cell adhesion GO:0032922 circadian regulation of gene expression GO:0042752 regulation of circadian rhythm GO:0043153 entrainment of circadian clock by photoperiod GO:0048511 rhythmic process GO:0051301 cell division