Chemiluminescence in Dictyostelium discoideum

Oxygen radicals generated during oxidative metabolism participate in chemical reactions resulting in light emission. Chemiluminescence is used therefore to measure their production. We have shown that starvation and heat shock induce chemiluminescence in Dictyostelium discoideum. The peak light emission was found to occur about 4 h after the onset of starvation. The optimum temperature for chemiluminescence by starving amoebae was about 33°C. The heat shock inducibility of chemiluminescence was maximal at the beginning of development. Our results are consistent with suggestions that the product(s) of perturbed mitochondrial metabolism might be intracellular signal(s) controlling gene expression in stressed cells. They also suggest a role for intracellular stress signal(s) in the initiation of development in Dictyostelium by starvation.