Non-canonical Autophagy: Facts and Prospects

Abstract

Macroautophagy is a catabolic process for cell components and terminates in the lysosomal compartment. Macroautophagy maintains the homeostasis of cells, tissues, and organisms, and plays important physiological roles during the development and aging processes. It also contributes to the innate and adaptive immune responses. The cytoprotective function of macroautophagy is compromised in diseases such as cancer, neurodegenerative disorders, and diabetes. The autophagosome, the central organelle in macroautophagy that sequesters cytoplasmic material, is formed by the hierarchical recruitment of 15 autophagy-related (ATG) proteins. However, alternatively to this canonical pathway, autophagosomes can also be formed by using only a subset of ATGs. Here, we will discuss recent discoveries concerning the molecular regulation of these non-canonical forms of macroautophagy and their potential role in the cellular response to stressful situations.