Mitochondria are organelles that are known for providing the energy currency that fuels chemical reactions within cells, but they are also involved in other important processes vital for cell health including the innate immune response to pathogens like viruses, programmed cell death, and communication with the rest of the cell—processes that all play a role in health and disease. The signaling proteins that serve as the mitochondria's interface with the rest of the cell are key players in these processes.