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Resolving vesicle fusion from lysis to monitor calcium-triggered lysosomal exocytosis in astrocytes.

ABSTRACT: Optical imaging of individual vesicle exocytosis is providing new insights into the mechanism and regulation of secretion by cells. To study calcium-triggered secretion from astrocytes, we used acridine orange (AO) to label vesicles. Although AO is often used for imaging exocytosis, we found that imaging vesicles labeled with AO can result in their photolysis. Here, we define experimental and analytical approaches that permit us to distinguish unambiguously between fusion, leakage, and lysis of individual vesicles. We have used this approach to demonstrate that lysosomes undergo calcium-triggered exocytosis in astrocytes.

SUBMITTER: Jaiswal JK

PROVIDER: S-EPMC1955787 | biostudies-literature | 2007 Aug

REPOSITORIES: biostudies-literature

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Resolving vesicle fusion from lysis to monitor calcium-triggered lysosomal exocytosis in astrocytes.

Jaiswal Jyoti K JK Fix Marina M Takano Takahiro T Nedergaard Maiken M Simon Sanford M SM

Proceedings of the National Academy of Sciences of the United States of America 20070821 35

Optical imaging of individual vesicle exocytosis is providing new insights into the mechanism and regulation of secretion by cells. To study calcium-triggered secretion from astrocytes, we used acridine orange (AO) to label vesicles. Although AO is often used for imaging exocytosis, we found that imaging vesicles labeled with AO can result in their photolysis. Here, we define experimental and analytical approaches that permit us to distinguish unambiguously between fusion, leakage, and lysis of ...[more]

PMID: 17715060

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