Postprenylation

Postprenylation is a type of protein modification where prenyl groups, typically farnesyl or geranylgeranyl pyrophosphate, are attached to cysteine residues within specific C-terminal motifs of target proteins. This process, also known as prenylation or isoprenylation, is catalyzed by enzymes called prenyltransferases, specifically farnesyltransferase (FTase) and geranylgeranyltransferase (GGTase). These enzymes play a crucial role in the post-translational modification of numerous proteins involved in diverse cellular processes. The attachment of these lipid moieties enhances the protein's lipophilicity, facilitating its association with cellular membranes. This membrane localization is often essential for the protein's function, enabling its interaction with other membrane-bound proteins or components of signaling pathways. Examples of proteins that undergo postprenylation include small GTPases like Ras and Rho, as well as proteins involved in vesicular transport and signal transduction. Aberrant postprenylation can lead to cellular dysfunction and has been implicated in various diseases, including cancer. Therefore, understanding the mechanisms and consequences of postprenylation is an active area of research in cell biology and medicine.