The catalytic conversion of UTP to CTP is accomplished by the enzyme cytidine-5-prime-triphosphate synthetase. The enzyme is important in the biosynthesis of phospholipids and nucleic acids, and plays a key role in cell growth, development, and tumorigenesis. The region to which the CTPS gene has been mapped is the location of breakpoints involved in several tumor types [provided by RefSeq, Jul 2008]