Myosin 5a controls insulin granule recruitment during late-phase secretion.
Författare
Summary, in English
We have examined the importance of the actin-based molecular motor myosin 5a for insulin granule transport and insulin secretion. Expression of myosin 5a was downregulated in clonal INS-1E cells using RNAinterference. Stimulated hormone secretion was reduced by 46% and single-cell exocytosis, measured by capacitance recordings, was inhibited by 42% after silencing. Silencing of Slac-2c/MYRIP, which links insulin granules to myosin 5a, resulted in similar inhibition of single-cell exocytosis. Antibody inhibition of the myosin 5a-Slac-2c/MYRIP interaction significantly reduced the recruitment of insulin granules for release. The pool of releasable granules independent of myosin 5a activity was estimated to approximately 550 granules. Total internal reflection microscopy was then applied to directly investigate granule recruitment to the plasma membrane. Silencing of myosin 5a inhibited granule recruitment during late phase of insulin secretion. In conclusion, we propose a model where insulin granules are transported through the actin network via both myosin 5a-mediated transport and via passive diffusion, with the former playing the major role during stimulatory conditions.
Avdelning/ar
Publiceringsår
2005
Språk
Engelska
Sidor
1027-1035
Publikation/Tidskrift/Serie
Traffic: the International Journal of Intracellular Transport
Volym
6
Issue
11
Fulltext
- Available as PDF - 226 kB
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Länkar
Dokumenttyp
Artikel i tidskrift
Förlag
Wiley-Blackwell
Ämne
- Basic Medicine
Status
Published
Forskningsgrupp
- Diabetes - Islet Patophysiology
ISBN/ISSN/Övrigt
- ISSN: 1398-9219