Protein phosphatase 1 catalytic subunit (PP1C) (PP1C)

Protein phosphatase 1 (PP1) catalytic subunits are essential enzymes that mediate the dephosphorylation of serine and threonine residues, regulating approximately one-third of all protein dephosphorylation events in eukaryotic cells (UniProt: P62136; Bollen et al., 2010, PMID: 20179718). In humans, the catalytic subunit exists in three highly conserved isoforms—alpha, beta/delta, and gamma—which rarely function in isolation (Ferreira et al., 2019, PMID: 30634510). Instead, they associate with over 200 different regulatory subunits to form specific holoenzymes that target distinct substrates and cellular compartments (Heroes et al., 2013, PMID: 23266578). This modularity allows PP1 to control diverse processes including glycogen metabolism, muscle contraction, cell cycle progression, and synaptic plasticity (Cohen, 2002, PMID: 12209150). Dysregulation of PP1 activity is implicated in various pathologies, such as heart failure, where overactivity can impair cardiac relaxation, and cancer, where it influences tumor suppressor and oncogene signaling (Bollen et al., 2010, PMID: 20179718). While traditional small-molecule inhibitors like okadaic acid lack specificity and are primarily used as research tools, modern therapeutic strategies focus on modulating specific PP1-regulatory subunit interactions to treat neurodegenerative and metabolic disorders (Peti et al., 2013, PMID: 23353711).

Other names

PPP1CAPPP1CBPPP1CCSerine/threonine-protein phosphatase 1PP-1PP1 catalytic subunit alphaPP1 catalytic subunit betaPP1 catalytic subunit gamma

PP1 catalytic subunits function as serine/threonine-specific protein phosphatases that hydrolyze phosphoric acid esters from protein substrates (UniProt: P62136). Their activity is typically directed by regulatory subunits that form a metal-ion-dependent catalytic site capable of dephosphorylating a wide range of targets when properly localized (Bollen et al., 2010, PMID: 20179718).