May be involved in the synthesis of minor phospholipids and in modulation of IP3-mediated signal transduction. Promotes the biosynthesis of plastidial phosphatidylglycerol (PG) which is required for structure and function of thylakoid membranes and, hence, for photoautotrophic growth. a 1,2-diacyl-sn-glycero-3-phosphate + CTP + H(+) = a CDP-1,2-diacyl-sn-glycerol + diphosphate Requires a divalent cation for activity. Displays highest activities with MgCl(2). Highest activities is obtained at about 30 mM CTP and 2 mM phosphatidic acid (PA). Optimum pH is 7.5. Phospholipid metabolism; CDP-diacylglycerol biosynthesis; CDP-diacylglycerol from sn-glycerol 3-phosphate: step 3/3. When associated with the disruption of CDS5, requires sucrose (Suc) treatment to grow. Pale yellow-green leaves with reduced chlorophyll levels but an increased chlorophyll a/b ratio. Reduced plastidial phosphatidylglycerol (PG) biosynthesis leading to abnormal thylakoid membrane development. Produced by alternative initiation. Produced by a combination of alternative splicing and alternative initiation. Produced by alternative splicing. Belongs to the CDS family.