Pinning Down Fusion Pores

Science's STKE  13 Apr 2004:
Vol. 2004, Issue 228, pp. tw137-TW137
DOI: 10.1126/stke.2282004TW137

The fusion pore for exocytosis, which can be defined biophysically, can be modulated by synaptotagmin, a protein found on synaptic vesicles. However, the nature of the fusion pore itself remains unclear. It is not even known whether the fusion pore is composed of lipid or protein. Han et al. identify a specific plasma membrane protein, syntaxin, as a physical part of the fusion pore during Ca2+-dependent exocytosis from a rat neuroendocrine cell line. Mutations within the transmembrane segment of syntaxin altered both neurotransmitter flux through fusion pores and pore conductance.

X. Han, C.-T. Wang, J. Bai, E. R. Chapman, M. B. Jackson, Transmembrane segments of syntaxin line the fusion pore of Ca2+-triggered exocytosis. Science 304, 289-292 (2004). [Abstract] [Full Text]