Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
Pt 1
pubmed:dateCreated
2001-1-26
pubmed:abstractText
Cellubrevins are integral membrane proteins expressed in a wide variety of tissues and usually localized in recycling vesicles. Here, we investigated the cellular localization of a cellubrevin-related peptide, endobrevin, in pancreatic (beta) cells and its implication in the exo-endocytosis of insulin and (gamma)-amino butyric acid (GABA). Immunocytochemistry showed that endobrevin is associated with tubulo-vesicular structures, which are colocalized with early endosomes labeled by early endosome antigen (EEA)-1 in insulinoma MIN6 cells. To determine the cellular localization of endobrevin, we appended the green fluorescent protein (GFP) to endobrevin and the fusion protein was introduced into MIN6 cells. The subcellular localization of GFP-endobrevin was visualized by confocal laser microscopy. Colocalization study based on the expressed GFP-endobrevin and endocytosed Texas-Red(Tx-R) labeled transferrin receptor and immunocytochemistry with anti-EEA1 antibody revealed that endobrevin was preferentially localized in the early endosome. Then, we examined the functional role of endobrevin in the exocytosis of insulin and GABA from pancreatic (beta) cells. Endobrevin overexpression increased the amount of GABA released from MIN6 cells; in contrast, it decreased the glucose-stimulated insulin release from rat islets, MIN6 and INS1-D cells to approximately 50% of the control levels. Both in vitro and in vivo binding studies showed that endobrevin binds to syntaxin 1. Finally, using the fluorescent probe FM4-64, it was revealed that endobrevin overexpression accelerates vesicle recycling. We conclude that (1) endobrevin is localized in the early endosome in pancreatic (beta) cells and (2) endobrevin plays a physiological role in the exo-endocytosis of insulin and GABA from pancreatic (beta) cells, probably via an interaction between endocytic vesicles and the endosome.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/FM 4-64, http://linkedlifedata.com/resource/pubmed/chemical/Fluorescent Dyes, http://linkedlifedata.com/resource/pubmed/chemical/Insulin, http://linkedlifedata.com/resource/pubmed/chemical/Membrane Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Peptides, http://linkedlifedata.com/resource/pubmed/chemical/Pyridinium Compounds, http://linkedlifedata.com/resource/pubmed/chemical/Qa-SNARE Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Quaternary Ammonium Compounds, http://linkedlifedata.com/resource/pubmed/chemical/R-SNARE Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Transferrin, http://linkedlifedata.com/resource/pubmed/chemical/Recombinant Fusion Proteins, http://linkedlifedata.com/resource/pubmed/chemical/STX1A protein, human, http://linkedlifedata.com/resource/pubmed/chemical/Stx1a protein, rat, http://linkedlifedata.com/resource/pubmed/chemical/Syntaxin 1, http://linkedlifedata.com/resource/pubmed/chemical/Texas red, http://linkedlifedata.com/resource/pubmed/chemical/VAMP8 protein, human, http://linkedlifedata.com/resource/pubmed/chemical/Vamp8 protein, rat, http://linkedlifedata.com/resource/pubmed/chemical/Vesicle-Associated Membrane..., http://linkedlifedata.com/resource/pubmed/chemical/Xanthenes, http://linkedlifedata.com/resource/pubmed/chemical/gamma-Aminobutyric Acid
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0021-9533
pubmed:author
pubmed:issnType
Print
pubmed:volume
114
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
219-227
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed-meshheading:11112705-Animals, pubmed-meshheading:11112705-Endocytosis, pubmed-meshheading:11112705-Endosomes, pubmed-meshheading:11112705-Exocytosis, pubmed-meshheading:11112705-Fluorescent Dyes, pubmed-meshheading:11112705-Gene Expression, pubmed-meshheading:11112705-Humans, pubmed-meshheading:11112705-Insulin, pubmed-meshheading:11112705-Islets of Langerhans, pubmed-meshheading:11112705-Membrane Proteins, pubmed-meshheading:11112705-Peptides, pubmed-meshheading:11112705-Pyridinium Compounds, pubmed-meshheading:11112705-Qa-SNARE Proteins, pubmed-meshheading:11112705-Quaternary Ammonium Compounds, pubmed-meshheading:11112705-R-SNARE Proteins, pubmed-meshheading:11112705-Rats, pubmed-meshheading:11112705-Receptors, Transferrin, pubmed-meshheading:11112705-Recombinant Fusion Proteins, pubmed-meshheading:11112705-Secretory Vesicles, pubmed-meshheading:11112705-Syntaxin 1, pubmed-meshheading:11112705-Vesicle-Associated Membrane Protein 3, pubmed-meshheading:11112705-Xanthenes, pubmed-meshheading:11112705-gamma-Aminobutyric Acid
pubmed:year
2001
pubmed:articleTitle
Localization of cellubrevin-related peptide, endobrevin, in the early endosome in pancreatic beta cells and its physiological function in exo-endocytosis of secretory granules.
pubmed:affiliation
Departments of Biochemistry, Clinical Pathology, Internal Medicine (III), Kyorin University School of Medicine, Mitaka, Tokyo 181-8611, Japan. shinya@kyorin-u.ac.jp
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't