Macroautophagy (hereinafter referred to simply as autophagy) is a lysosome-mediated intracellular degradation process that involves the bulk segregation and digestion of portions of the cytoplasm in membrane-enclosed vacuoles 1 . The dynamic process of autophagy starts with the formation of a cup-shaped membrane sac (known as the isolation membrane or phagophore) which engulfs a portion of cytoplasm, and then elongates and seals off to form a double-membraned autophagosome. The autophagosome fuses with lysosomes to form the autolysosome, where the cargo together with the inner membrane of the autophagosome is degraded. Finally, the digested material is released back into the cytosol through lysosomal permeases for recycling 1 . Autophagy plays an important role in a wide variety of physiological processes in higher eukaryotes, including adaptation to various metabolic stress conditions, removal of aggregate-prone proteins and damaged organelles, and elimination of invading pathogens. Dysregulated autophagy activity has been linked to various pathological diseases such as neurodegeneration, cardiomyopathy and tumorigenesis 2 .