Fig. 2.

Schematic representation of autophagy and autophagy-related pathways. These dynamic pathways can be broken down into a series of steps including induction, cargo recognition and packaging, vesicle nucleation, vesicle expansion and completion, Atg protein cycling, vesicle fusion with the vacuole/lysosome, vesicle breakdown and recycling of the resulting macromolecules. The Atg proteins can be classified into several different groups according to their functions at the different steps of the pathway. The Atg1 complex may act at multiple steps of the pathway, including induction and Atg protein cycling. During the vesicle formation process, several Atg proteins are involved in cycling between the peripheral sites and the PAS. PAS, phagophore assembly site; thought to be the organizing site for phagophore formation. This figure is modified from Fig. 2 of Huang and Klionsky (2007)