Sytidiinitrifosfaatti

Sytidiinitrifosfaatti, often abbreviated as CTP, is a nucleoside triphosphate. It plays a crucial role in various biological processes, most notably as a substrate in the synthesis of cytidine-containing RNA and in the biosynthesis of phospholipids. CTP is composed of cytosine, a ribose sugar, and three phosphate groups. The energy stored in the high-energy phosphate bonds of CTP is utilized during metabolic reactions.

In cellular metabolism, CTP is synthesized from cytidine diphosphate (CDP) by the addition of a phosphate group, a reaction catalyzed by the enzyme nucleoside diphosphate kinase. This process is part of the nucleotide salvage pathway and de novo nucleotide synthesis. The breakdown of CTP, releasing energy, occurs through hydrolysis.

A key function of CTP is its role in the CDP-choline pathway and the CDP-ethanolamine pathway, both essential for the synthesis of phosphatidylcholine and phosphatidylethanolamine, respectively. These phospholipids are vital components of cell membranes. Additionally, CTP is a necessary precursor for the incorporation of cytidine into RNA during transcription. Its presence and regulation are critical for maintaining cellular function and genetic information transfer.