second protein kinase C conserved region 1 (C1 domain) found in diacylglycerol kinase alpha (DAG kinase alpha) and similar proteins
Diacylglycerol (DAG) kinase (EC 220.127.116.11) is a lipid kinase that phosphorylates diacylglycerol to form phosphatidic acid. DAG kinase alpha, also called 80 kDa diacylglycerol kinase, or diglyceride kinase alpha (DGK-alpha), converts the second messenger diacylglycerol into phosphatidate upon cell stimulation, initiating the resynthesis of phosphatidylinositols and attenuating protein kinase C activity. It is classified as a type I DAG kinase (DGK), containing EF-hand structures that bind Ca(2+) and a recoverin homology domain, in addition to C1 and catalytic domains that are present in all DGKs. As a type I DGK, it is regulated by calcium binding. DAG kinase alpha contains two copies of the C1 domain. This model corresponds to the second 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.