Signal-dependent membrane targeting by pleckstrin homology (PH) domains

摘要: Pleckstrin homology (PH) domains are small protein modules of around 120 amino acids found in many proteins involved cell signalling, cytoskeletal rearrangement and other processes. Although several different ligands have been proposed for PH domains, their only clearly demonstrated physiological function to date is bind membrane phosphoinositides. The domain from phospholipase C-delta(1) binds specifically PtdIns(4,5)P(2) its headgroup, has become a valuable tool studying cellular functions. More recent developments that subset recognizes the products agonist-stimulated phosphoinositide 3-kinases. Fusion these green fluorescent allowed dramatic demonstrations independent ability drive signal-dependent recruitment host plasma membrane. We discuss structural basis this 3-phosphoinoistide recognition role it plays signalling. phosphoinositides comprise minority (perhaps 15%) those known, raising questions as remaining 85% domains. Most (if not all) weakly non-specifically Studies dynamin-1 indicated oligomerization may be important driving association. possibility targeting by with low affinity could driven alteration oligomeric state thus avidity binding.