Fig. 1.

Cx50 hemichannels are opened by H₂O₂ and inhibited by Cx50 mutants in a dominant-negative manner. CEF cells were infected with high-titer RCAS(A) retroviral vehicle (V) or recombinant RCAS(A) retroviruses containing WT Cx50, Cx50 mutants, E48K, P88S or H156N, or Cx50 WT and mutants in combination. (A) Whole-cell lysate extracts were prepared and then immunoblotted with anti-FLAG or β-actin antibody. (B) Cells were cultured at low density then treated with 0.3 mM H₂O₂ for 2 h, and 0.05 mM cabenoxolone for 20 min, followed by incubating with 0.1 mM EtBr for 5 min. At least four microphotographs of fluorescence fields were taken under a 20× microscope (Olympus) with a Rhodamine filter. The average pixel density of 30 random cells was measured by using ImageJ software. The data are presented as the mean±s.e.m. (n=3). ***P<0.001. Scale bar: 100 μm.