Lymphocyte-specific inducible expression of potassium channel beta subunits

Abstract

Many studies have shown that voltage-gated potassium (Kv) channel activity is essential for T-lymphocyte proliferation. The IL-2-inducible neuroimmune gene, I2rf5 is the mouse homologue of the rat Kv beta 2 subunit. In this study we show that in addition to constitutive expression in adult murine brain, expression of Kv channel subunits beta 1.1 and beta 2.1 is inducible in a cloned T-helper cell line stimulated with IL-2 and in normal murine splenocytes stimulated with Con A or LPS. This expression pattern appears to be lymphocyte specific, because stimulated fibroblasts and vascular smooth muscle cells do not express Kv beta channel subunit mRNA. These observations suggest that Kv beta subunit expression is tissue specific and inducible in stimulated lymphocytes. Because Kv beta subunits modulate K+ channel activity, the inducible and variable expression of these subunits in lymphocytes may represent an additional regulatory mechanism for lymphocyte proliferation.