UTP (Uridine Triphosphate)

UVR G enes 2101 random deamination of cytosine residues. Efficient surveillance and repair systems exist within most cells to prevent uracil residues from accumulating within DNA. Because the base-pairing properties of uracil are identical to those of thymine, replication of DNA containing a G:U base pair would give rise to a daughter molecule containing an A:U base pair and a granddaughter molecule containing an A:T base pair. If the original G:C base pair happened to be indispensable, the failure to replace U would be lethal. See also: Pyrimidine

URF Copyright ß 2001 Academic Press doi: 10.1006/rwgn.2001.2067

A URF (unidentified reading frame) is an open reading frame that is presumed to code for protein, but for which no product has been found. See also: Reading Frame

UTP (Uridine Triphosphate) E J Murgola Copyright ß 2001 Academic Press doi: 10.1006/rwgn.2001.1359

Uridine-50 -triphosphate (UTP) is an energy-rich, activated precursor for RNA synthesis. It is synthesized in the cell by phosphorylation of uridine diphosphate (UDP), catalyzed by a nucleoside diphosphate kinase, with adenosine triphosphate (ATP) as the phosphate donor: UDP ‡ ATP

UTP ‡ ADP

For the synthesis of deoxyuridine triphosphate (dUTP), a precursor of DNA, the 20 hydroxyl group of the ribose moiety of guanosine triphosphate (GTP) is replaced by a hydrogen atom. The final step in this conversion is catalyzed by ribonucleotide reductase. See also: RNA

UVR Genes See: Excision Repair