Supplemental Figure S1
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Fig. S1. S50P requires Cx46 to form functional hemichannels in Xenopus oocytes. (A) Single oocytes expressing wild-type Cx46 were clamped at a holding potential of −40 mV and subjected to voltage applications ranging from −30 mV to +60 mV in 10-mV steps. A representative trace displayed voltage induced outward membrane currents that increased in magnitude with time. (C) By contrast, cells expressing S50P subunits alone showed negligible membrane currents at all voltages analyzed. (E,F) Voltage-induced membrane currents were exhibited by cells expressing either (E) wild-type Cx50 and Cx46 or (F) wild-type Cx46 and S50P. Steady-state currents measured after 7 seconds of an initial voltage pulse were plotted as a function of membrane voltage. (B) Steady-state currents in wild-type Cx46 injected oocytes displayed increasing whole-cell currents at all positive voltage application (n=10, white squares). (D) Conversely, cells expressing S50P connexins alone, exhibited negligible membrane currents at voltages analyzed (n=7, black triangles). (F) Wild-type Cx50 and Cx46 currents showed an approximately twofold reduction compared with wild-type Cx46 injected cells at all voltages analyzed (n=10, white diamonds). (H) Similarly, oocytes co-expressing wild-type Cx46 and S50P subunits induced whole cell currents comparable to those exhibited by wild-type Cx50 and Cx46 co-injected oocytes (n=10, black circles). Data are the mean ± s.e.m.
