Mitochondria are cellular organelles with their own genome (mtDNA) that are involved in several biological processes such as energy metabolism and signal transduction. Increasing evidence indicates that mitochondria also have a critical role in innate immunity, but it is unclear how variation in mtDNA affects responses to infection. In a new study, researchers used a panel of fruit fly Drosophila melanogaster cytoplasmic hybrids (cybrids), where specific mtDNA variants (mitotypes) are introgressed into the same donor nuclear DNA background by repeated backcrossing, to assess the effects of mtDNA variation on infection outcomes. The researchers focused on four different mitotypes, which showed either weak (mtORT, mtBS1) or strong (mtKSA2 and mtWT5A) immune responses against bacterial pathogens. mtKSA2 mitotype also protected flies against parasitoid and viral infections, suggesting that specific mitotypes can provide broad protection against infections. Future work using the Drosophila model will help further understand how variation in immune responses arises from mitochondrial variation.
Original reference: Salminen, T. S. et al. PLoS Genet. 20, e1011476 (2024)
This is a preview of subscription content, access via your institution
