Trafficking and signaling in mammalian autophagy

Macroautophagy, here called autophagy, is literally a "self-eating" catabolic process, which is evolutionarily conserved. Autophagy is initiated by cellular stress pathways, resulting in the sequestration or engulfment of cytosolic proteins, membranes, and organelles in a double membrane structure that fuses with endosomes and lysosomes, thus delivering the sequestered material for degradation. Autophagy is implicated in a number of human diseases, many of which can either be characterized by an imbalance in protein, organelle, or cellular homeostasis, ultimately resulting in an alteration of the autophagic response. Here, we will review the recent progress made in understanding the induction of autophagy, with emphasis on the contributions from our laboratory.