Chapter 17 Modulation of Mitochondria During Viral Infections

Mitochondria are organelles critical for cell survival because they produce ATP and modulate programmed cell death (PCD) pathways. PCD pathways are important in many clinical disorders, such as ischemia/reperfusion injuries, trauma, and toxic/metabolic syndromes, as well as in chronic neurodegenerative conditions, such as amyotrophic lateral sclerosis, Alzheimer’s disease, Parkinson’s disease, and Huntington’s disease. Moreover, many viruses and other pathogens target the mitochondria. Viruses induce the production of various proteins in their hosts that have proapoptotic and anti-apoptotic activities, depending on the cellular environment. More specifically, many viruses that target mitochondria regulate the balance between the antiand proapoptotic Bcl-2 family proteins and thereby increase their own survival within the host cell. Recent studies indicated that mitochondria centralize several critical innate immune responses based on the presence of several important signaling proteins within the mitochondria: mitochondrial antiviral signaling (MAVS), stimulation of interferon genes (STING), and NLR family member X1. Therefore, mitochondria are not only vital because they regulate cell survival and death but also they have broad roles in the control of cell functions following pathogen invasion. This chapter highlights the tight interplay between viral infection and mitochondria.