protein kinase C conserved region 1 (C1 domain) found in the Myotonic dystrophy kinase-related Cdc42-binding kinase (MRCK) family
MRCK is thought to be a coincidence detector of signaling by the small GTPase Cdc42 and phosphoinositides. MRCK/Cdc42 signaling mediates myosin-dependent cell motility. MRCK has been shown to promote cytoskeletal reorganization, which affects many biological processes. Three isoforms of MRCK are known, named alpha, beta and gamma. MRCKgamma is expressed in heart and skeletal muscles, unlike MRCKalpha and MRCKbeta, which are expressed ubiquitously. MRCK consists of a serine/threonine kinase domain, a cysteine rich (C1) region, a PH domain and a p21 binding motif. This model corresponds to C1 domain. The C1 domain is a cysteine-rich zinc binding domain that does not bind DNA nor possess structural similarity to conventional zinc finger domains; it contains two separate Zn(2+)-binding sites.