HIV-1 gp160 decreases the K+ voltage-gated current from Jurkat E6.1 T cells by up-phosphorylation

HIV-1 gp120/gp160 is known to disturb the activity of p56(lck), protein kin ase C (PKC) and Ca2+ homeostasis in T lymphocytes. We found that gp160 decr eases the Kv1.3 current of Jurkat E6.1 cells probably by increasing the PKC -dependent phosphorylation of Kv channel protein after 5 days. This decreas e is dose-dependent. In contrast, gp160 did not decrease the Kv1.3 current of the JCaM1.6 cell line, a p56(lck)-defective Jurkat cell line. This shows that p56(lck) was at the beginning of the events which induced the Kv1.3 c urrent decrease. As a consequence of this decrease, Jurkat E6.1 cells were depolarized and exhibited a volume increase. (C) 1999 Federation of Europea n Biochemical Societies.