Phosphatase 1 (PPP1CA) Active Protein

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. Increased PP1 activity has been observed in the end stage of heart failure. Studies in both human and mice suggest that PP1 is an important regulator of cardiac function. Mouse studies also suggest that PP1 functions as a suppressor of learning and memory. Three alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jul 2008]

PPP1CA: is a catalytic subunit of protein phosphatase 1 (PP1), aubiquitous cytosolic serine-threonine phosphatase. Composed of 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: PPP1R12A and PPP1R12B mediate binding to myosin; PPP1R3A, PPP1R3B, PPP1R3C and PPP1R3D mediate binding to glycogen; and PPP1R15A and PPP1R15B mediate binding to EIF2S1. PP1 is essential for cell division, plays critical roles in many cellular processes including glycogen metabolism, muscle contractility and protein synthesis, and is involved in the regulation of ionic conductances and long-term synaptic plasticity. Inhibits the synthesis of proteins involved in synaptic plasticity. Binds to the transcription factor cyclic AMP-dependent response element binding (CREB) and dephosphorylates it. May regulate chromatin condensation through regulation of histone H3 phosphorylation. Differentially expressed in gastric cancer. May participate in the neurodegenerative progress in Alzheimer's disease. Down-regulated in lung squamous cell carcinoma.

Protein type: Protein phosphatase, Ser/Thr (non-receptor); Nucleolus; EC 3.1.3.16

Chromosomal Location of Human Ortholog: 11q13

Cellular Component: nucleoplasm; glycogen granule; cytoplasm; nucleolus; dendritic spine; plasma membrane; perikaryon; protein phosphatase type 1 complex; nucleus; cytosol

Molecular Function: ribonucleoprotein binding; protein binding; metal ion binding; phosphoric monoester hydrolase activity; protein serine/threonine phosphatase activity

Biological Process: glycogen metabolic process; regulation of glycogen catabolic process; branching morphogenesis of a tube; cell division; transforming growth factor beta receptor signaling pathway; triacylglycerol catabolic process; regulation of glycogen biosynthetic process; circadian regulation of gene expression; negative regulation of transforming growth factor beta receptor signaling pathway; cell cycle; regulation of circadian rhythm; protein amino acid dephosphorylation; lung development; entrainment of circadian clock by photoperiod