Protein phosphorylation and the regulation of synaptic membrane traffic

It is well established that protein phosphorylation has an important role i n synaptic plasticity. This is achieved, in part, via the presynaptic modul ation of neurotransmitter release by protein kinases and protein phosphatas es. in recent years, the increase in information available about proteins t hat are involved in synaptic exocytosis and endocytosis has been exploited in order to study the effects of protein phosphorylation on synaptic-vesicl e cycling at the molecular level, The best-characterized protein in this re spect is synapsin, whose function in the release of synaptic vesicles from the reserve pool is regulated by phosphorylation. More recently, it has eme rged that proteins that function at other stages of the synaptic-vesicle cy cle, which include priming of vesicles for docking-fusion and endocytic rec ycling, are also controlled by phosphorylation. Furthermore, recent work su ggests that this regulation of membrane traffic by phosphorylation also occ urs postsynaptically, where it contributes to synaptic plasticity.