| CTP:phosphocholine cytidylyltransferase (CCT) is a critical enzyme that regulates the CDP-choline pathway for the biosynthesis of phosphatidylcholine. Three distinct CCT isoforms are found in mammals, including CCTα, CCTβ2, and CCTβ3. CCTα is the major isoform that is expressed in most tissues. CCTα is essential in the synthesis and secretion of surfactant by alveolar epithelial cells and is important in maintaining the phosphatidylcholine level that regulates lipoprotein assembly and secretion in hepatocytes. CCTα is a major component in membrane biogenesis during cytokine secretion by stimulated macrophages. Monoubiquitination of CCTα prevents it from entering the nucleus and leads to its degradation by lysosome. |
