To assess whether connexin (Cx) expression contributes to insulin secretion, we have investigated normal and tumoral insulin-producing cells for connexins, gap junctions, and coupling. We have found that the glucose-sensitive cells of pancreatic islets and of a rat insulinoma are functionally coupled by gap junctions made of Cx43. In contrast, cells of several lines secreting insulin abnormally do not express Cx43, gap junctions, and coupling. After correction of these defects by stable transfection of Cx43 cDNA, cells expressing modest levels of Cx43 and coupling, as observed in native beta-cells, showed an expression of the insulin gene and an insulin content that were markedly elevated, compared with those observed in both wild-type (uncoupled) cells and in transfected cells overexpressing Cx43. These findings indicate that adequate levels of Cx-mediated coupling are required for proper insulin production and storage.
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December 15 1995
Adequate connexin-mediated coupling is required for proper insulin production.
C Vozzi,
C Vozzi
Department of Morphology, University of Geneva Medical School, Switzerland.
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S Ullrich,
S Ullrich
Department of Morphology, University of Geneva Medical School, Switzerland.
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A Charollais,
A Charollais
Department of Morphology, University of Geneva Medical School, Switzerland.
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J Philippe,
J Philippe
Department of Morphology, University of Geneva Medical School, Switzerland.
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L Orci,
L Orci
Department of Morphology, University of Geneva Medical School, Switzerland.
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P Meda
P Meda
Department of Morphology, University of Geneva Medical School, Switzerland.
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C Vozzi
Department of Morphology, University of Geneva Medical School, Switzerland.
S Ullrich
Department of Morphology, University of Geneva Medical School, Switzerland.
A Charollais
Department of Morphology, University of Geneva Medical School, Switzerland.
J Philippe
Department of Morphology, University of Geneva Medical School, Switzerland.
L Orci
Department of Morphology, University of Geneva Medical School, Switzerland.
P Meda
Department of Morphology, University of Geneva Medical School, Switzerland.
Online ISSN: 1540-8140
Print ISSN: 0021-9525
J Cell Biol (1995) 131 (6): 1561–1572.
Citation
C Vozzi, S Ullrich, A Charollais, J Philippe, L Orci, P Meda; Adequate connexin-mediated coupling is required for proper insulin production.. J Cell Biol 15 December 1995; 131 (6): 1561–1572. doi: https://doi.org/10.1083/jcb.131.6.1561
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