Intracellular K+ suppresses the activation of apoptosis in lymphocytes.

Published

Journal Article

Little is known about the mechanisms of suppression of apoptosis. We have addressed the novel possibility that the level of intracellular K+ regulates the apoptotic process by controlling the activity of death enzymes. We show that K+, at normal intracellular levels, inhibits both apoptotic DNA fragmentation and caspase-3(CPP32)-like protease activation, suggesting that intracellular K+ loss must occur early during apoptosis. Direct measurement of K+ by inductively coupled plasma/mass spectrometry and flow cytometry indicates a major decrease in intracellular K+ concentration in the apoptotic cell. Flow cytometric analysis revealed that caspase and nuclease activity were restricted to the subpopulation of cells with reduced K+. Disruption of the natural K+ electrochemical gradient suppressed the activity of both caspase and nuclease independent of the mode of activation of the apoptotic inducing agent, demonstrating that a decrease in intracellular K+ concentration is a necessary, early event in programmed cell death.

Full Text

Duke Authors

Cited Authors

  • Hughes, FM; Bortner, CD; Purdy, GD; Cidlowski, JA

Published Date

  • November 28, 1997

Published In

Volume / Issue

  • 272 / 48

Start / End Page

  • 30567 - 30576

PubMed ID

  • 9374553

Pubmed Central ID

  • 9374553

International Standard Serial Number (ISSN)

  • 0021-9258

Digital Object Identifier (DOI)

  • 10.1074/jbc.272.48.30567

Language

  • eng

Conference Location

  • United States