Currents through the fusion pore that forms during exocytosis of a secretory vesicle

  title={Currents through the fusion pore that forms during exocytosis of a secretory vesicle},
  author={L. J. Breckenridge and Wolfhard Almers},
Exocytosis, or the fusion of cytoplasmic vesicles with the cell membrane, occurs in nearly all eukaryotic cells, but its mechanism is not understood. Morphological1,2 and electrophysiological studies3–5 have suggested that membrane fusion begins with the formation of a 'fusion pore', a narrow channel across the closely adjacent membranes of vesicle and cell that forms the first connection of the vesicle lumen with the cell exterior and later dilates to allow release of vesicle contents. We used… 
The exocytotic fusion pore interface: a model of the site of neurotransmitter release.
Comparisons of experimental data with theoretical fusion pores and with breakdown pores support the view that the fusion pore is initially a pore through a single bilayer, as would be expected for membrane fusion proceeding through a hemifusion mechanism.
Exocytotic fusion pore under stress
Post-fusion mechanisms that regulate fusion pore stability are considered, reflecting the state in which the forces of widening and constriction of fusion pores are balanced.
Phases of the exocytotic fusion pore
The regulation of fusion pore expansion or closure is key to regulate the release of neurotransmitters and hormones and the implications in the modes of exocytosis are discussed.
Temporal Separation of Vesicle Release from Vesicle Fusion during Exocytosis*
It is demonstrated that an osmotic gradient across the fusion pore is an important driving force for exocytotic extrusion of granule contents from secretory cells following fusion pores formation.
Patch Clamp Measurements of Exocytosis
The application of patch clamp techniques to monitor the activity of individual fusion pores in mast cells has generated a wealth of novel and unexpected observations and the results are now being reproduced in other secretory cells suggesting that the conclusions may have wider significance in other membrane fusion reactions.
Two modes of fusion pore opening revealed by cell-attached recordings at a synapse
Results show that ‘kiss-and-run’ fusion occurs at synapses and that it can generate rapid postsynaptic currents, and suggest that various fusion pore sizes help to control the kinetics and amplitude of synaptic currents.