Figure 4.

Detergent-solubility of Cx43 in RL-EΔN and RL-NΔE cells. (A) Total (T), TX-100-soluble (S), and TX–insoluble (I) fractions from cells were analyzed by Western blot analysis as described in Materials and Methods. The blots were stripped and reprobed with anti–β-actin antibody to verify equal loading. Note that Cx43 is detected in both detergent-soluble and detergent-insoluble fractions in both cell types. (B) Detergent solubility of Cx43 was examined in cells upon in situ extraction with 1% Triton X-100 at 4°C as described in Materials and Methods. Cells were immunostained for Cx43 (green) and β-catenin (red). Note that both junctional Cx43 in RL-EΔN cells and intracellular Cx43 in RL-NΔE cells were detergent-insoluble. Note also that the intensity of β-catenin at the areas of cell–cell contact is not significantly affected by the detergent treatment. Bar = 15 μm.