Intracellular potassium (K+) concentration decrease is not obligatory for apoptosis
2011 (English)In: Journal of Biological Chemistry, ISSN 0021-9258, E-ISSN 1083-351X, Vol. 286, no 46, 39823-39828 p.Article in journal (Refereed) Published
K+ efflux is observed as an early event in the apoptotic process in various cell types. Loss of intracellular K+ and subsequent reduction in ionic strength is suggested to release the inhibition of proapoptotic caspases. In this work, a new K+-specific microelectrode was used to study possible alterations in intracellular K+ in Xenopus laevis oocytes during chemically induced apoptosis. The accuracy of the microelectrode to detect changes in intracellular K+ was verified with parallel electrophysiological measurements within the same cells. In concordance with previous studies on other cell types, apoptotic stimuli reduced the intracellular K+ concentration in Xenopus oocytes and increased caspase-3 activity. The reduction in intracellular K+ was prevented by dense expression of voltage-gated K (Kv) channels. Despite this, the caspase-3 activity was increased similarly in Kv channel expressing oocytes as in oocytes not expressing Kv channels. Thus, in Xenopus oocytes caspase-3 activity is not dependent on the intracellular concentration of K+.
Place, publisher, year, edition, pages
American Society for Biochemistry and Molecular Biology , 2011. Vol. 286, no 46, 39823-39828 p.
Caspase-3 activation, Electrophysiology, Intracellular K+ concentrations, K+-selective microelectrode, Xenopus laevis oocytes
IdentifiersURN: urn:nbn:se:liu:diva-68853DOI: 10.1074/jbc.M111.262725ISI: 000296925700016OAI: oai:DiVA.org:liu-68853DiVA: diva2:421418
Funding agencies|Swedish Research Council||Swedish Heart-Lung Foundation||Swedish Brain Foundation||County Council of Ostergotland, King Gustaf V and Queen Victorias Freemasons Foundation||Swedish Society for Medical Research||2011-06-082011-06-082014-10-06Bibliographically approved