Phospho-CPI17 alpha (Thr38) Antibody detects endogenous levels of CPI17 alpha only when phosphorylated at Threonine 38. PPP1R14A a phosphorylation-dependent inhibitory subunit of protein phosphatase 1 (PP-1A). Phosphorylation by PKC regulates its binding to PP-1A. Acts co-operatively to inhibit myosin light chain phosphatase (MLCP) activity.