Sex differences in antiviral immunity in SARS-CoV-2 infection. Mitochondria and mitomiR come into view

Mitochondria are multifaceted organelles representing the ‘powerhouse of cells’ for their function as bioenergetics and biosynthetic hubs. In addition, they play an essential role in the regulation of innate and adaptive immune responses, including host defences against viruses, as well as in in- flammatory responses. This peculiar role of mitochondria is principally because of the activation of adaptor mitochon- drial proteins, known as mitochondrial antiviral signalling (MAVS) proteins. MAVS senses viral RNA and triggers the activation of the transcription factor NF-kB or IFN pathways and autophagy, in order to clear the infection and avoid exces- sive inflammation respectively.