Journal article
Direct Imaging of RAB27B-Enriched Secretory Vesicle Biogenesis in Lacrimal Acinar Cells Reveals Origins on a Nascent Vesicle Budding Site
PloS one, Vol.7(2), pp.e31789-e31789
02/20/2012
DOI: 10.1371/journal.pone.0031789
PMCID: PMC3282733
PMID: 22363735
Abstract
This study uses YFP-tagged Rab27b expression in rabbit lacrimal gland acinar cells, which are polarized secretory epithelial cells, to characterize early stages of secretory vesicle trafficking. Here we demonstrate the utility of YFP-Rab27b to delineate new perspectives on the mechanisms of early vesicle biogenesis in lacrimal gland acinar cells, where information is significantly limited. Protocols were developed to deplete the mature YFP-Rab27b-enriched secretory vesicle pool in the subapical region of the cell, and confocal fluorescence microscopy was used to track vesicle replenishment. This analysis revealed a basally-localized organelle, which we termed the "nascent vesicle site,'' from which nascent vesicles appeared to emerge. Subapical vesicular YFP-Rab27b was co-localized with p150(Glued), a component of the dynactin cofactor of cytoplasmic dynein. Treatment with the microtubule-targeted agent, nocodazole, did not affect release of mature secretory vesicles, although during vesicle repletion it significantly altered nascent YFP-Rab27b-enriched secretory vesicle localization. Instead of moving to the subapical region, these vesicles were trapped at the nascent vesicle site which was adjacent to, if not a sub-compartment of, the trans-Golgi network. Finally, YFP-Rab27b-enriched secretory vesicles which reached the subapical cytoplasm appeared to acquire the actin-based motor protein, Myosin 5C. Our findings show that Rab27b enrichment occurs early in secretory vesicle formation, that secretory vesicles bud from a visually discernable nascent vesicle site, and that transport from the nascent vesicle site to the subapical region requires intact microtubules.
Details
- Title: Subtitle
- Direct Imaging of RAB27B-Enriched Secretory Vesicle Biogenesis in Lacrimal Acinar Cells Reveals Origins on a Nascent Vesicle Budding Site
- Creators
- Lilian Chiang - University of Southern CaliforniaSerhan Karvar - University of Southern CaliforniaSarah F. Hamm-Alvarez - Univ So Calif, Sch Pharm, Los Angeles, CA 90089 USA
- Resource Type
- Journal article
- Publication Details
- PloS one, Vol.7(2), pp.e31789-e31789
- Publisher
- Public Library Science
- DOI
- 10.1371/journal.pone.0031789
- PMID
- 22363735
- PMCID
- PMC3282733
- ISSN
- 1932-6203
- eISSN
- 1932-6203
- Number of pages
- 10
- Grant note
- R01EY011386 / NATIONAL EYE INSTITUTE; United States Department of Health & Human Services; National Institutes of Health (NIH) - USA; NIH National Eye Institute (NEI) R01EY011386 / National Institutes of Health; United States Department of Health & Human Services; National Institutes of Health (NIH) - USA
- Language
- English
- Date published
- 02/20/2012
- Academic Unit
- Internal Medicine
- Record Identifier
- 9984695833502771
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