Protein phosphatase 1 regulatory subunit 14C is an enzyme that in humans is encoded by the PPP1R14C gene.

The degree of protein phosphorylation is regulated by a balance of protein kinase and phosphatase activities. Protein phosphatase-1 (PP1; see MIM 176875) is a signal-transducing phosphatase that influences neuronal activity, protein synthesis, metabolism, muscle contraction, and cell division. PPP1R14C is an inhibitor of PP1 (Liu et al., 2002 [PubMed 11812771]).[supplied by OMIM, Feb 2010].
Function: Inhibitor of PPP1CA. Has over 600-fold higher inhibitory activity when phosphorylated, creating a molecular switch for regulating the phosphorylation status of PPP1CA substrates and smooth muscle contraction (By similarity).