Plant Selective Autophagy-Still an Uncharted Territory With a Lot of Hidden Gems

Selective autophagy has emerged as a major quality control pathway that surgically removes damaged or unwanted macromolecules to maintain cellular health. Defects in selective autophagy have been linked with several neurodegenerative and metabolic diseases, and aging in animal models. Similarly, genetic studies have shown that autophagy is involved in a wide range of stress responses in plants. Over the last decade, as discussed in other review articles in this special issue, ground-breaking studies in yeast and mammalian models uncovered molecular details of selective cargo recognition and autophagosome biogenesis. However, despite the growing interest in green autophagy, we still have large gaps in our understanding of selective autophagy processes in plants. In this opinion article, we will highlight some of these unknowns that motivate us and discuss how we are trying to address them. Furthermore, we will propose a three-layered approach, already feasible in Arabidopsis root, that envisions to bridge mechanistic studies with cell type and stimulus-specific autophagy dynamics that could reveal the extent to which selective autophagy contributes to organismal fitness. Altogether, we hope it will provide a framework for future studies that move beyond genetic analysis and aim to mechanistically unravel how selective autophagy contributes to plant survival. (C) 2019 The Authors. Published by Elsevier Ltd.