(A–D) The proliferation of CEF cells expressing Cx50 (WT or V362E mutant), Cx43, Cx46, or/and Skp2 (or Skp2 shRNAs) via retroviral infection or p27 siRNA was measured by BrdU labeling assay.
(A) Cx50 inhibits cell proliferation, but not Cx43 or Cx46, and Skp2 suppresses the inhibitory effect by Cx50.
(B) Cx50(V362E) mutant does not inhibit the stimulatory effect by overexpressing Skp2.
(C) Inhibition of Skp2 by either of the two Skp2 shRNAs suppresses the cellular proliferation and augments the inhibitory effect of Cx50.
(D) p27 siRNA increased cell proliferation and attenuated the inhibitory effect of Cx50.
(E) Cx50 delays cell-cycle progression, but Cx50(V362E) mutant does not. CEF cells were labeled with PI and analyzed with FACS.
All data were presented as the means ± SEM (n = 3–5), *p < 0.05; **p < 0.01; ***p < 0.001, compared to vehicle control group, unless marked otherwise. N.S., not significant.