Inhibition of phosphatases and increased Ca2+ channel activity by inositol hexakisphosphate

Olof Larsson, Christopher J. Barker, Åke Sjöholm, Håkan Carlqvist, Robert H. Michell, Alejandro Bertorello, Thomas Nilsson, Richard E. Honkanen, Georg W. Mayr, Jean Zwiller, Per Olof Berggren

Research output: Contribution to journalArticle

115 Scopus citations

Abstract

Inositol hexakisphosphate (InsP6), the dominant inositol phosphate in insulin-secreting pancreatic β cells, inhibited the serine-threonine protein phosphatases type 1, type 2A, and type 3 in a concentration-dependent manner. The activity of voltage-gated L-type calcium channels is increased in cells treated with inhibitors of serine-threonine protein phosphatases. Thus, the increased calcium channel activity obtained in the presence of InsP6 might result from the inhibition of phosphatase activity. Glucose elicited a transient increase in InsP6 concentration, which indicates that this inositol polyphosphate may modulate calcium influx over the plasma membrane and serve as a signal in the pancreatic β cell stimulus-secretion coupling.

Original languageEnglish (US)
Pages (from-to)471-474
Number of pages4
JournalScience
Volume278
Issue number5337
DOIs
StatePublished - Oct 17 1997

    Fingerprint

ASJC Scopus subject areas

  • General

Cite this

Larsson, O., Barker, C. J., Sjöholm, Å., Carlqvist, H., Michell, R. H., Bertorello, A., Nilsson, T., Honkanen, R. E., Mayr, G. W., Zwiller, J., & Berggren, P. O. (1997). Inhibition of phosphatases and increased Ca2+ channel activity by inositol hexakisphosphate. Science, 278(5337), 471-474. https://doi.org/10.1126/science.278.5337.471