protein kinase C conserved region 1 (C1 domain) found in the atypical protein kinase C (aPKC) zeta type
PKCs are classified into three groups (classical, atypical, and novel) depending on their mode of activation and the structural characteristics of their regulatory domain. aPKCs only require phosphatidylserine (PS) for activation. They contain a C2-like region, instead of a calcium-binding (C2) region found in classical PKCs, in their regulatory domain. There are two aPKC isoforms, zeta and iota. aPKCs are involved in many cellular functions including proliferation, migration, apoptosis, polarity maintenance and cytoskeletal regulation. They also play a critical role in the regulation of glucose metabolism and in the pathogenesis of type 2 diabetes. PKC-zeta plays a critical role in activating the glucose transport response. It is activated by glucose, insulin, and exercise through diverse pathways. PKC-zeta also plays a central role in maintaining cell polarity in yeast and mammalian cells. In addition, it affects actin remodeling in muscle cells. Members of this family contain C1 domain found in aPKC isoform zeta. 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.