Digesting the Expanding Mechanisms of Autophagy. Issue 8 (August 2016)

• Record Type: Journal Article
• Authors: Ktistakis, Nicholas T.; Tooze, Sharon A.
• Is Part Of: Trends in cell biology. Volume 26:Issue 8(2016)
• Page Start: 624
• Page End: 635
• Publication Date: 2016-08
• Subjects: autophagosomes -- selective autophagy -- organelles -- Vps34 complex -- noncanonical autophagy; Cytology -- Periodicals; Cytology -- Research -- Periodicals; 571.6
• DOI: 10.1016/j.tcb.2016.03.006
• Languages: English
• ISSNs: 0962-8924

Abstract

Abstract : Autophagy is a catabolic 'self-eating' pathway that is emerging as a crucial integration point in cell physiology. With its own set of genes, the autophagy pathway communicates with virtually all signalling networks and organelles. Recent advances have been made in understanding the origin of the autophagosomal membrane, novel regulators, and the mechanisms by which specific intracellular membranes become autophagy substrates. New studies on noncanonical autophagy, mediated by subsets of autophagy proteins, and the role of autophagy proteins in non-autophagy pathways are also emerging in many different biological contexts. Our understanding of canonical autophagy, including membrane origin and autophagy proteins, needs to be considered together with emerging noncanonical pathways. Trends: While nucleation of the autophagosome requires multiple membrane sources, formation of the double membrane is aided by actin filaments recruited by phosphatidylinositol 3-phosphate (PI3P). Maturation of autophagosomes requires vesicle fusion proteins (SNARES and tethers) but these are regulated in unexpected ways by post-translational modifications and by interactions with Atg proteins that are also used in other steps of the pathway. Newly identified cargo receptors show how selective autophagy can target the endoplasmic reticulum (ER) and parts of the nucleus and that this is required to prevent neurological disease. Noncanonical autophagy – for example, LC3-associated phagocytosis (LAP) – is becoming better understood through a greater understanding of the regulatory steps involved. An emerging area is the noncanonical use of autophagy proteins in non-autophagy pathways.