Referenced in: none

Automatically associated channels: Kv1.1 , Kv1.3

Title: Identification of Kv1.1 expression by murine CD4-CD8- thymocytes. A role for voltage-dependent K+ channels in murine thymocyte development.

Authors: B D Freedman, B K Fleischmann, J A Punt, G Gaulton, Y Hashimoto, M I Kotlikoff

Journal, date & volume: J. Biol. Chem., 1995 Sep 22 , 270, 22406-11

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/7673227

Abstract
The patch-clamp recording technique and RNA-polymerase chain reaction were used to identify the voltage-dependent K+ channels expressed by murine fetal and adult CD4-CD8- thymocytes. Two distinct currents, encoded by the genes Kv1.1 and Kv1.3 were identified based upon their biophysical and pharmacologic characteristics and confirmed with RNA-polymerase chain reaction. Peptide blockers of Kv1.1 and Kv1.3 gene products were also applied to a murine fetal thymic organ culture system to investigate the developmental role of these K+ channels. Dendrotoxin (DTX) and charybdotoxin (CTX), antagonists of Kv1.1 and Kv1.3 channels, respectively, decreased thymocyte yields in organ culture without affecting thymocyte viability. DTX-treated thymi contained 56 +/- 8% (n = 8 experiments), and CTX-treated thymi contained 74 +/- 4% (n = 7 experiments) as many thymocytes as untreated lobes. DTX and CTX also altered the developmental progression of thymocytes in fetal organ culture. These data provide the first evidence of Kv1.1 expression in a lymphoid cell and indicate that thymocyte voltage-dependent K+ channels are critical to thymocyte preclonal expansion and/or maturation.