farnylopolifosforanu

Farnesyl pyrophosphate (FPP) is a key intermediate in isoprenoid biosynthesis, a vital metabolic pathway found in all living organisms. It serves as a universal precursor for a vast array of essential molecules. FPP is synthesized from the condensation of isopentenyl pyrophosphate (IPP) and dimethylallyl pyrophosphate (DMAPP), with the enzyme farnesyl pyrophosphate synthase catalyzing this reaction. IPP and DMAPP themselves are derived from the mevalonate pathway or the non-mevalonate pathway, depending on the organism.

The significance of FPP lies in its role as a building block. It can be elongated by further condensation with IPP to form geranylgeranyl pyrophosphate (GGPP), which is then used in the synthesis of carotenoids, gibberellins, and tocopherols. Alternatively, FPP can undergo cyclization reactions, leading to the formation of sterols and other cyclic isoprenoids. In many eukaryotes, FPP is also involved in protein prenylation, a post-translational modification where prenyl groups are attached to specific cysteine residues of proteins. This modification is crucial for membrane localization and proper function of many signaling proteins, including Ras and Rho GTPases. The diverse downstream products derived from FPP highlight its central importance in cellular metabolism, growth, and development.