Secretory control: evidence for agonist regulation of post-fusion vesicle behaviour.
1. Here, we review recent work on vesicular secretion, with a focus on the control of post-fusion events as a means of regulating secretory output. 2. In the classical model of secretion, each fused vesicle releases the entirety of its content in an all-or-none manner. In this way, the secretory output of a cell is controlled by regulating the numbers of fused vesicles. The realisation that post-fusion events can control secretory output leads to a distinct model of partial release of vesicle content. 3. Recent work shows that post-fusion events are under cellular control. Further, new data from our laboratory demonstrates agonist-dependent regulation of fusion pore behaviour. 4. We conclude that post-fusion events are not epiphenomena, but are likely an important mechanism of secretory control.
Soekmadji
Carolina
C
School of Biomedical Sciences, University of Queensland, Brisbane, Queensland, Australia.
Thorn
Peter
P
D002118:Calcium / Q000502:physiology; D002919:Chymotrypsinogen / Q000502:physiology; D006801:Humans; D008561:Membrane Fusion / Q000502:physiology*; D010179:Pancreas / Q000502:physiology; D055571:Secretory Pathway / Q000502:physiology*; D022142:Secretory Vesicles / Q000378:metabolism*; D012697:Serine Endopeptidases / Q000502:physiology
D002919:Chymotrypsinogen; D012697:Serine Endopeptidases; C028736:zymogen E; D002118:Calcium