This paper describes the development of a Dictyostelium discoideum strain deficient in frataxin protein (FXN). The authors investigated the conservation of function between humans and D. discoideum and showed that DdFXN can substitute the human version in the interaction and activation of the Fe-S assembly supercomplex. The D. discoideum fxn locus was edited and a defective mutant, clone 8, was isolated, which presents landmarks of frataxin deficiency, such as a decrease in Fe-S cluster-dependent enzymatic functions, growth rate reduction, and increased sensitivity to oxidative stress. In addition, the multicellular development is affected as well as growing on bacterial lawn. The rescuing capacity of DdFXN-G122V, a version that mimics a human variant present in some FA patients, was also assessed. While the expression of DdFXN-G122V rescues growth and enzymatic activity defects, as DdFXN does, multicellular development defects were only partially rescued. The results of the study suggest that this new D. discoideum strain offers a wide range of possibilities to easily explore diverse FA FXN variants. This can facilitate the development of straightforward drug screenings to look for new therapeutic strategies.

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