FIGURE 7.

Effect of SUMO-3 on Cx43 gap junction channel function. HeLa cells were transfected with empty plasmids, Cx43 alone, or Cx43 together with HA-SUMO-3. The level of gap junctional communication was determined by quantitative scrape loading dye transfer. In accordance with previous studies, treatment of Cx43-transfected cells with chlordane (30 μm) for 30 min resulted in complete inhibition of gap junctional intercellular communication, and was used to define zero communication. Values shown are the mean ± S.E. of four independent experiments, relative to cells transfected with only Cx43. Note that cells transfected with empty plasmid were found to have low levels of gap junction intercellular communication, as they expressed low amounts of endogenous Cx43.