Interspecies transfer of mitochondria in Paramecium aurelia.

Erythromycin-resistant mitochondria from species 1, 5 and 7 of P. aurelia were injected into erythromycin-sensitive paramecia of each of the same three species. Mitochondria from species 1 and 5 were successfully transferred to all three species, but species 7 mitochondria failed to develop in species 1 and 5. Minor differences were indicated in the frequency of successful transfers of species 1 mitochondria into species 1 and 5 cells. From studies on the transferability of mitochondria from "hybrid" cells, containing mitochondria from one species and nuclei from another, it was concluded that mitochondrial compatibility was mainly under control of the nuclear genome, with a possible minor control also by the mitochondrial genome.