Docking of secretory vesicles is syntaxin dependent

Heidi de Wit, L. Niels Cornelisse, Ruud F.G. Toonen, Matthijs Verhage*

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

Abstract

Secretory vesicles dock at the plasma membrane before they undergo fusion. Molecular docking mechanisms are poorly defined but believed to be independent of SNARE proteins. Here, we challenged this hypothesis by acute deletion of the target SNARE, syntaxin, in vertebrate neurons and neuroendocrine cells. Deletion resulted in fusion arrest in both systems. No docking defects were observed in synapses, in line with previous observations. However, a drastic reduction in morphologically docked secretory vesicles was observed in chromaffin cells. Syntaxin-deficient chromaffin cells showed a small reduction in total and plasma membrane staining for the docking factor Munc18-1, which appears insufficient to explain the drastic reduction in docking. The sub-membrane cortical actin network was unaffected by syntaxin deletion. These observations expose a docking role for syntaxin in the neuroendocrine system. Additional layers of regulation may have evolved to make syntaxin redundant for docking in highly specialized systems like synaptic active zones.

Original languageEnglish
Article numbere126
JournalPLoS ONE
Volume1
Issue number1
DOIs
Publication statusPublished - 27 Dec 2006
Externally publishedYes

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