THE DNAJ-LIKE CYSTEINE STRING PROTEIN AND EXOCYTOTIC NEUROTRANSMITTERRELEASE

The fast, tightly regulated release of neurotransmitters from presynap tic nerve terminals is effected by a complex molecular apparatus. The precise roles of the various proteins involved remain largely conjectu ral. Cysteine string proteins (CSPs) are novel synaptic vesicle compon ents that have been conserved in evolution. They are characterized by an N-terminus 'J'-domain and a central, multiply palmitoylated string of cysteine residues. Vertebrate CSPs have been implicated in a functi onal interaction of synaptic vesicles with presynaptic Ca2+ channels. Genetic 'knockout' of CSPs in Drosophila results in a temperature-sens itive breakdown of elicited transmitter release. Here we try to integr ate these observations into speculative functional models on the role of this new protein family in synaptic vesicle exocytosis.