Selective nucleotide-release from dense-core granules in insulin-secreting cells.

Research output: Contribution to journalArticle

Abstract

Secretory granules of insulin-secreting cells are used to store and release peptide hormones as well as low-molecular-weight compounds such as nucleotides. Here we have compared the rate of exocytosis with the time courses of nucleotide and peptide release by a combination of capacitance measurements, electrophysiological detection of ATP release and single-granule imaging. We demonstrate that the release of nucleotides and peptides is delayed by similar to 0.1 and similar to 2 seconds with respect to membrane fusion, respectively. We further show that in up to 70% of the cases exocytosis does not result in significant release of the peptide cargo, likely because of a mechanism that leads to premature closure of the fusion pore. Release of nucleotides and protons occurred regardless of whether peptides were secreted or not. These observations suggest that insulin-secreting cells are able to use the same secretory vesicles to release small molecules either alone or together with the peptide hormone.

Details

Authors
  • Stefanie Obermüller
  • Anders Lindqvist
  • Jovita Karanauskaite
  • Juris Galvanovskis
  • Patrik Rorsman
  • Sebastian Barg
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Basic Medicine
  • Endocrinology and Diabetes

Keywords

  • insulin, hormone, fusion pore, exocytosis, endocytosis, kiss-and-run, secretion
Original languageEnglish
Pages (from-to)4271-4282
JournalJournal of Cell Science
Volume118
Issue numberPt 18
Publication statusPublished - 2005
Publication categoryResearch
Peer-reviewedYes

Related research output

Karanauskaite, J., 2008, Department of Clinical Sciences, Lund University. 101 p.

Research output: ThesisDoctoral Thesis (compilation)

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