Myosin 2 maintains an open exocytic fusion pore in secretory epithelial cells

Bhat, Purnima and Thorn, Peter (2009) Myosin 2 maintains an open exocytic fusion pore in secretory epithelial cells. Molecular Biology of the Cell, 20 6: 1795-1803. doi:10.1091/mbc.E08-10-1048

Attached Files (Some files may be inaccessible until you login with your UQ eSpace credentials)
Name Description MIMEType Size Downloads
UQ183709_OA.pdf Full text (open access) application/pdf 363.75KB 0

Author Bhat, Purnima
Thorn, Peter
Title Myosin 2 maintains an open exocytic fusion pore in secretory epithelial cells
Journal name Molecular Biology of the Cell   Check publisher's open access policy
ISSN 1059-1524
Publication date 2009-03
Sub-type Article (original research)
DOI 10.1091/mbc.E08-10-1048
Open Access Status File (Publisher version)
Volume 20
Issue 6
Start page 1795
End page 1803
Total pages 9
Editor David Botstein
Place of publication Bethesda, MD, United States
Publisher American Society for Cell Biology
Collection year 2010
Language eng
Subject C1
920109 Infectious Diseases
060602 Animal Physiology - Cell
060111 Signal Transduction
110307 Gastroenterology and Hepatology
111601 Cell Physiology
Abstract Many studies have implicated F-actin and myosin 2 in the control of regulated secretion. Most recently, evidence suggests a role for the microfilament network in regulating the postfusion events of vesicle dynamics. This is of potential importance as postfusion behavior can influence the loss of vesicle content and may provide a new target for drug therapy. We have investigated the role of myosin 2 in regulating exocytosis in secretory epithelial cells by using novel assays to determine the behavior of the fusion pore in individual granules. We immunolocalize myosin 2A to the apical region of pancreatic acinar cells, suggesting it is this isoform that plays a role in granule exocytosis. We further show myosin 2 phosphorylation increased on cell stimulation, consistent with a regulatory role in secretion. Importantly, in a single-cell, single-granule secretion assay, neither the myosin 2 inhibitor (-)-blebbistatin nor the myosin light chain kinase inhibitor ML-9 had any effect on the numbers of granules stimulated to fuse after cell stimulation. These data indicate that myosin 2, if it has any action on secretion, must be targeting postfusion granule behavior. This interpretation is supported by direct study of fusion pore opening in which we show that (-)-blebbistatin and ML-9 promote fusion pore closure and decrease fusion pore lifetimes. Our work now adds to a growing body of evidence showing that myosin 2 is an essential regulator of postfusion granule behavior. In particular, in the case of the secretory epithelial cells, myosin 2 activity is necessary to maintain fusion pore opening.
Q-Index Code C1
Q-Index Status Confirmed Code
Institutional Status UQ

Document type: Journal Article
Sub-type: Article (original research)
Collections: 2010 Higher Education Research Data Collection
ERA 2012 Admin Only
School of Biomedical Sciences Publications
Version Filter Type
Citation counts: TR Web of Science Citation Count  Cited 31 times in Thomson Reuters Web of Science Article | Citations
Scopus Citation Count Cited 31 times in Scopus Article | Citations
Google Scholar Search Google Scholar
Created: Mon, 07 Sep 2009, 14:46:01 EST by Cameron Harris on behalf of School of Biomedical Sciences