Commentary Cell Science Reviews Vol 6 No 2 ISSN 1742-8130

An old dog learns a new trick: Synaptotagmin, a Ca²⁺ sensor for spontaneous release at central synapses

Evoked and spontaneous neurotransmitter release mechanisms are known to share similar components. Synaptotagmin-1 (Syt-1) plays a pivotal role in evoked neurotransmitter release as a Ca²⁺ sensor, but has also been implicated in the regulation of spontaneous release. Its repertoire has now been extended as a recent study, performed on central synapses, confirms the role of Syt-1 in spontaneous release, as a Ca²⁺ sensor, a fusion clamp and now as an inhibitor of a second, unknown Ca²⁺ sensor. In this commentary we discuss the significance of these findings with regard to previous studies performed on the Drosophila neuromuscular junction and in mouse neurons. We also discuss the intriguing possibility of neuronal-context dependent regulation of Syt-1 function. The implication of additional Ca²⁺ sensors in neurotransmission and the analysis of their interplay with Syt-1 in both evoked and spontaneous neurotransmission will contribute to our understanding of the mechanisms underlying neurotransmission as well helping to elucidate the functional significance of spontaneous neurotransmitter release.

Click to access complete issue ($9.49) and to download full article in or formats