Fig. 5. Gap junctions form between transduced pseudo-islets made of non-infected and transduced islet cells. (A) Minute gap junctional plaques (arrowheads) associated with linear particle arrays were detected by freeze-fracture electron microscopy at membrane interfaces of non-infected primary ß-cells. In ß-cells transduced with a lentiviral vector coding for Cx32, Cx36 or Cx43, larger gap junctional plaques were seen between endocrine cells. (B) When assessed by western blotting, extracts of control, uninfected pseudo-islets confirmed the native expression of Cx36, whose levels were increased markedly after transduction with a lentiviral vector coding for Cx36. Samples of pancreatic islets and Min6 cells served as positive controls, whereas heart was used as a negative control. All lanes were loaded with 40 µg protein.