Linked Life Data

12047554

Source:http://linkedlifedata.com/resource/pubmed/id/12047554

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7
pubmed:dateCreated
2002-6-5
pubmed:abstractText
We combined confocal and live-cell imaging with a novel molecular strategy aimed at revealing mechanisms underlying glucose-regulated insulin vesicle secretion. The 'Ins-C-GFP' reporter monitors secretory peptide targeting, trafficking, and exocytosis without directly tagging the mature secreted peptide. We trapped a green fluorescent protein (GFP) reporter in equimolar quantity within the secretory vesicle by fusing it within the C peptide of proinsulin which only after nascent vesicle sealing and acidification is cleaved from the mature secreted A and B chains of insulin. Ins-C-GFP expression in mouse islets without fail exhibited punctate distribution of green fluorescence by confocal microscopy. Ins-C-GFP colocalized GFP with insulin at vesicle dense cores by immuno-electron microscopy. Glucose stimulation decreased vesicle fluorescence coordinately with enhanced secretion from islets of C-GFP detected by anti-GFP Western blots, and of insulin detected by anti-insulin radioimmunoassay. An insulin secretagogue with a red fluorescent label, glibenclamide BODIPY TR, was applied to islets expressing Ins-C-GFP. The stimulus response was imaged as a rise in red secretagogue leading to marked loss in green granules. Since neuropeptides as well as peptide hormones are processed from propeptides after sealing of secretory granules, vesicle trapping likely is widely applicable for studies on targeting, trafficking, and regulated release of secretory peptides.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
1398-9219
pubmed:author
pubmed:issnType
Print
pubmed:volume
3
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
461-71
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed:year
2002
pubmed:articleTitle
Imaging secretory vesicles by fluorescent protein insertion in propeptide rather than mature secreted peptide.
pubmed:affiliation
Department of Cell Biology and Physiology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA.
pubmed:publicationType
Journal Article, In Vitro, Research Support, Non-U.S. Gov't