dCTP

Deoxycytidine triphosphate (dCTP) is one of the four deoxyribonucleoside triphosphates that serve as substrates for DNA synthesis. It consists of the deoxyribose sugar attached to the cytosine base and three phosphate groups. In nucleotide pools, dCTP is one of the building blocks incorporated into a growing DNA chain by DNA polymerases, pairing with guanine on the template strand.

Biological role and metabolism: In cells, dCTP is produced by phosphorylation of dCMP to dCDP and then to dCTP, via a series of kinases and nucleoside diphosphate kinases. Cellular dNTP pools are tightly regulated because imbalances can increase misincorporation during replication and cause mutations. dCTP participates in DNA repair and replication, and its intracellular level fluctuates during the cell cycle and in response to metabolic state. Depletion of dCTP or imbalances can activate checkpoints and reduce replication speed.

Applications: In molecular biology, dCTP is used in in vitro DNA synthesis reactions such as PCR and primer extension, usually as part of a mixture of all four dNTPs. It is also used in sequencing chemistries and various DNA labeling techniques. Commercial preparations are available as individual nucleotides or as a balanced mix of the four dNTPs.

Chemistry and handling: dCTP is typically supplied as disodium or triphosphate salts and is stable when stored frozen at low temperatures. It should be protected from prolonged exposure to sunlight and moisture. Safety: considered low hazard; handle with standard laboratory precautions.