Identification of synaptic proteins and their isoform mRNAs in compartments of pancreatic endocrine cells

Gunilla Jacobsson, Andrew J. Bean, Richard H. Scheller, Lisa Juntti-Berggren, Jude T. Deeney, Per Olof Berggren, Björn Meister

Research output: Contribution to journalArticle

190 Scopus citations

Abstract

Several proteins that are of importance for membrane trafficking in the nerve terminal have recently been characterized. We have used Western blot and immunohistochemistry to show that synaptotagmin, synaptobrevin/VAMP (vesicle-associated membrane protein), SNAP-25 (synaptosomal-associated protein of 25 kDa), and syntaxin proteins are present in cells of the islets of Langerhans in the endocrine pancreas. Synaptotagmin-like immunoreactivity (-LI) was localized to granules within the cytoplasm of a few endocrine cells located in the periphery of the islets, identified as somatostatin-containing cells, and in many nerve fibers within the islets. VAMP-LI was seen in granules of virtually all pancreatic islet cells and also in nerve fibers. SNAP-25-LI and syntaxin-LI were predominantly present in the plasma membrane of the endocrine cells, including insulin-producing β cells. In situ hybridization, using isoform-specific oligonucleotide probes, detected VAMP- 2, cellubrevin, SNAP-25, syntaxin 1A, 4, and 5, and munc-18 mRNAs in isolated pancreatic islets and in insulin-producing cells. The results show the presence of several synaptic proteins at protein and mRNA levels in pancreatic islet cells, suggesting that they may have specific roles in the molecular regulation of exocytosis also in insulin-secreting cells.

Original languageEnglish (US)
Pages (from-to)12487-12491
Number of pages5
JournalProceedings of the National Academy of Sciences of the United States of America
Volume91
Issue number26
DOIs
StatePublished - Dec 20 1994

Keywords

  • diabetes
  • exocytosis
  • insulin
  • secretion

ASJC Scopus subject areas

  • Genetics
  • General

Fingerprint Dive into the research topics of 'Identification of synaptic proteins and their isoform mRNAs in compartments of pancreatic endocrine cells'. Together they form a unique fingerprint.

  • Cite this