third protein kinase C conserved region 1 (C1 domain) found in type V diacylglycerol kinase, DAG kinase theta, and similar proteins
Diacylglycerol (DAG) kinase (EC 22.214.171.124) is a lipid kinase that phosphorylates diacylglycerol to form phosphatidic acid. DAG kinase theta, also called diglyceride kinase theta (DGK-theta), is the only isoform classified as type V; it contains a pleckstrin homology (PH)-like domain and an additional C1 domain, compared to other DGKs. It may regulate the activity of protein kinase C by controlling the balance between the two signaling lipids, diacylglycerol and phosphatidic acid. DAG kinase theta contains three copies of the C1 domain. This model corresponds to the third one. 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.