Fig. 3.
Mutant channel α1CT1603D is resistant to the slow run-down. Representative time courses of run-down for the wild-type (A) and α1CT1603D (B) channels coexpressed with β2a in CHO cells. Inset graph in b shows relative NPo values for the wild-type and the mutant channels in the inside-out mode. Effects of CaM on α1CT1603D (C) and α1CT1603A (D) channels in the inside-out patch mode. CaM (1 μM) + ATP (3 mM) produced marked channel activity in α1CT1603D, but little in α1CT1603A. Representative current traces recorded in the cell-attached mode (a) and in the inside-out mode before (b) and after (c) application of CaM + ATP are shown in (C)