Role of autophagy in disease resistance and hypersensitive response-associated cell death.

Ancient autophagy pathways are emerging as key defense modules in host eukaryotic cells against microbial pathogens. Apart from actively eliminating intracellular intruders, autophagy is also responsible for cell survival, for example by reducing the deleterious effects of endoplasmic reticulum stress. At the same time, autophagy can contribute to cellular suicide. The concurrent engagement of autophagy in these processes during infection may sometimes mask its contribution to differing pro-survival and pro-death decisions. The importance of autophagy in innate immunity in mammals is well documented, but how autophagy contributes to plant innate immunity and cell death is not that clear. A few research reports have appeared recently to shed light on the roles of autophagy in plant-pathogen interactions and in disease-associated host cell death. We present a first attempt to reconcile the results of this research.