Figure 1.

VacA induces Cx43 increase, autophagy and apoptosis. VacA binds and is internalized by cells. Toxin channel activity impairs GSH metabolism (reactive oxygen species), activation of Rac1, and ERK phosphorylation. These signal transduction events lead to enhanced Cx43 endocytosis. Cx43 accumulated in cytoplasmic compartments through effects of toxin on pre-autophagy pathways and colocalized with autophagosomal marker LC3. Cells were incubated with 120 nM heat-inactivated (left panel) or wild-type VacA (right panel) for 10 h and then reacted with anti-Cx43 (green) and anti-LC3 antibodies (red) and were stained with DAPI (cyan). Bars represent 20 μm. The parts of yellow indicate the colocalization of Cx43 and LC3