Linked Life Data

12393909

Source:http://linkedlifedata.com/resource/pubmed/id/12393909

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
52
pubmed:dateCreated
2002-12-23
pubmed:abstractText
To investigate the in vivo interaction of syntaxin-mediated soluble N-ethylmaleimide-sensitive fusion protein attachment protein receptor (SNARE) assembly and insulin exocytosis in biphasic release, we examined the dynamics of insulin granule motion such as docking and fusion with the plasma membrane when the syntaxin SNARE motif (H3 domain) was transduced into living MIN6 beta cells. TAT-H3, produced by fusion of the protein transduction domain of human immunodeficiency virus-1 TAT to the syntaxin-H3 domain, was rapidly transduced into the subplasmalemmal region in living MIN6 cells. Immunoblotting analysis followed by immunoprecipitation on TAT-H3-treated MIN6 cells showed that TAT-H3 binds SNAP-25 and VAMP-2 in vivo. Transduction of MIN6 cells with TAT-H3 caused a decrease in both the first and second phase of insulin release. We therefore quantitatively analyzed approaching, docking, and fusing of green fluorescent protein-labeled single insulin granules in TAT-H3-transduced MIN6 cells by evanescent wave microscopy. Under high glucose stimulation, TAT-H3 treatment not only reduced the fusion events from previously docked granules for the first 120 s (first phase of release) but also strongly inhibited the docking and fusion from newly recruited insulin granules after this point (second phase of release). During the second phase of release we observed a marked reduction in the accumulation of newly docked insulin granules; subsequently, fusion events were significantly decreased. TAT-H3 treatment by itself, however, did not alter the number of previously docked granules without stimulation. We conclude that introduction of the H3 domain into MIN6 cells inhibits biphasic insulin release by two mechanisms. 1) In the first phase of insulin release, the H3 domain interferes with previously docked granules to be fused, and 2) in the second phase of insulin release reduced fusion events result from a marked decline of newly docked granules. Thus, syntaxin-mediated SNARE assembly modulates insulin exocytosis in biphasic insulin release in a distinct way.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
27
pubmed:volume
277
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
50805-11
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed-meshheading:12393909-Animals, pubmed-meshheading:12393909-Cell Fusion, pubmed-meshheading:12393909-Cell Line, pubmed-meshheading:12393909-Exocytosis, pubmed-meshheading:12393909-Glucose, pubmed-meshheading:12393909-Green Fluorescent Proteins, pubmed-meshheading:12393909-Insulin, pubmed-meshheading:12393909-Ionomycin, pubmed-meshheading:12393909-Islets of Langerhans, pubmed-meshheading:12393909-Kinetics, pubmed-meshheading:12393909-Luminescent Proteins, pubmed-meshheading:12393909-Membrane Proteins, pubmed-meshheading:12393909-Potassium Chloride, pubmed-meshheading:12393909-Qa-SNARE Proteins, pubmed-meshheading:12393909-Recombinant Fusion Proteins, pubmed-meshheading:12393909-SNARE Proteins, pubmed-meshheading:12393909-Transfection, pubmed-meshheading:12393909-Vesicular Transport Proteins
pubmed:year
2002
pubmed:articleTitle
Transduction of MIN6 beta cells with TAT-syntaxin SNARE motif inhibits insulin exocytosis in biphasic insulin release in a distinct mechanism analyzed by evanescent wave microscopy.
pubmed:affiliation
Department of Biochemistry, Kyorin University School of Medicine, Shinkawa 6-20-2, Mitaka, Tokyo 181-8611, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't