Virus and Autophagy: Enemies or Allies

Viral infection is one of the several stimuli which trigger autophagy, a self-degradative process that is important for balancing sources of energy at critical times in development and in response to nutrient stress. This process also plays a housekeeping role in removing misfolded or aggregated proteins and clearing damaged organelles. Virus-induced autophagy has a dual role since it may be beneficial to the host by eliminating intracellular pathogens or it may benefit some viruses, which have developed strategies to directly or indirectly subvert autophagy in order to promote different stages of the viral life cycle. The upregulation of both oxidative and endoplasmic reticulum stresses has been reported as a means by which virus-induced pathways trigger autophagy. In this chapter the relationships between autophagy and viral infection are considered.