Display Settings:

Format

Send to:

Choose Destination

    Diabetes. 2004 Dec;53 Suppl 3:S59-62.

    Integration of ATP, cAMP, and Ca2+ signals in insulin granule exocytosis.

    Shibasaki T, Sunaga Y, Seino S.

    Division of Cellular and Molecular Medicine, Kobe University Graduate School of Medicine, Kobe 650-0017, Japan.

    Intracellular ATP, cAMP, and Ca2+ are major signals involved in the regulation of insulin secretion in the pancreatic beta-cell. We recently found that the ATP-sensitive K+ channel (KATP channel) as an ATP sensor, cAMP-GEFII as a cAMP sensor, Piccolo as a Ca2+ sensor, and L-type voltage-dependent Ca2+ channel (VDCC) can interact with each other. In the present study, we examined the effects of cAMP and ATP on the interaction of cAMP-GEFII and sulfonylurea receptor-1 (SUR1). Interaction of cAMP-GEFII with SUR1 was inhibited by the cAMP analog 8-bromo-cAMP but not by ATP, and the inhibition by 8-bromo-cAMP persisted in the presence of ATP. In addition, SUR1, cAMP-GEFII, and Piccolo could form a complex. Piccolo also interacted with the alpha1 1.2 subunit of VDCC in a Ca2+-independent manner. These data suggest that the interactions of the KATP channel, cAMP-GEFII, Piccolo, and L-type VDCC are regulated by intracellular signals such as cAMP and Ca2+ and that the ATP, cAMP, and Ca2+ signals are integrated at a specialized region of pancreatic beta-cells.

    PMID: 15561922 [PubMed - indexed for MEDLINE]

    Supplemental Content

    Click here to read