CGS1

CGS1 is a gene name used in several organisms to designate cytidine triphosphate synthetase 1 (CTPS1), a member of the CTPS enzyme family. CTPS enzymes catalyze the ATP-dependent conversion of uridine triphosphate (UTP) to cytidine triphosphate (CTP), supplying nucleotides required for RNA and DNA synthesis and for phospholipid biosynthesis via the CDP-diacylglycerol pathway. In plants, CGS1 typically refers to one of the cytidine triphosphate synthetase genes and is expressed in actively growing tissues to help maintain cellular CTP pools.

Biochemical properties and regulation of CGS1 reflect the broader CTPS family. The enzyme uses ATP and serves as a key control point in pyrimidine nucleotide biosynthesis. Nitrogen and carbon status can influence CGS1 expression and activity, helping to coordinate nucleotide supply with metabolic demand. In many organisms, CTPS enzymes can assemble into filamentous structures known as cytoophidia, a phenomenon linked to regulation of catalytic activity in response to metabolic state.

Genetic and physiological roles of CGS1 are particularly prominent in plants, where the gene helps support rapid growth and development. Loss-of-function or reduction of CGS1 activity often leads to depleted CTP pools, with growth defects and developmental abnormalities. Conversely, higher CGS1 activity can elevate CTP availability, potentially affecting cell proliferation and stress responses. CGS1 operates within a broader CTPS gene family, with homologs present across taxa, and nomenclature may vary by species.

See also: cytidine triphosphate synthetase, CTPS family, cytoophidia.