RT Journal Article SR Electronic T1 The Stoned Proteins Regulate Synaptic Vesicle Recycling in the Presynaptic Terminal JF The Journal of Neuroscience JO J. Neurosci. FD Society for Neuroscience SP 5847 OP 5860 DO 10.1523/JNEUROSCI.19-14-05847.1999 VO 19 IS 14 A1 Tim Fergestad A1 Warren S. Davis A1 Kendal Broadie YR 1999 UL http://www.jneurosci.org/content/19/14/5847.abstract AB The Drosophila stoned locus was identified 25 years ago on the basis of stress-sensitive behavioral mutants (Grigliatti et al., 1973). The locus is dicistronic and encodes two distinct proteins, stoned A and stoned B, which are expressed specifically in presynaptic terminals at central and peripheral synapses. Severalstoned mutant alleles cause embryonic lethality, suggesting that these proteins are essential for synaptic function. Physiological analyses at the stoned synapse reveal severe neurotransmission defects, including reduced and asynchronous neurotransmitter release and rapid fatigue after repetitive stimulation. At the EM level, stoned synapses show a depletion of synaptic vesicles and a concomitant increase in membrane-recycling intermediates. Mutant terminals also display a specific mislocalization of the synaptic vesicle protein synaptotagmin. These results suggest that the stoned proteins are essential for the recycling of synaptic vesicle membrane and are required for the proper sorting of synaptotagmin during endocytosis.