Referenced in: none

Automatically associated channels: Kv1.3

Title: Ceramide-induced inhibition of T lymphocyte voltage-gated potassium channel is mediated by tyrosine kinases.

Authors: E Gulbins, I Szabò, K Baltzer, F Lang

Journal, date & volume: Proc. Natl. Acad. Sci. U.S.A., 1997 Jul 8 , 94, 7661-6

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/9207149

Abstract
The n-type K+ channel (n-K+, Kv1.3) in lymphocytes has been recently implicated in the regulation of Fas-induced programmed cell death. Here, we demonstrate that ceramide, a lipid metabolite synthesized upon Fas receptor ligation, inhibits n-K+ channel activity and induces a tyrosine phosphorylation of the Kv1.3 protein in Jurkat T lymphocytes. Tyrosine phosphorylation of the n-K+ channel correlated with an activation of the Src-like tyrosine kinase p56lck upon cellular treatment with the ceramide analog C6-ceramide. Because genetic deficiency of p56lck or inhibition of Src-like tyrosine kinases by herbimycin A prevented ceramide-mediated n-K+ channel inhibition and tyrosine phosphorylation, we propose a ceramide-initiated activation of p56lck resulting in tyrosine phosphorylation and inhibition of the n-K+ channel protein.