Autophagy: Versatility and Essentiality in Cellular Homeostasis and Beyond

Abstract

Autophagy, governed by autophagy-related genes (ATGs), is essential for cellular homeostasis. It impacts diverse cellular functions, including development, reproduction, metabolism, hormone signaling, cell death, senescence, and stress responses. The article delves into macro-autophagy, micro-autophagy, and chaperone-mediated autophagy (CMA), emphasizing cargo specificity. Bulk autophagy engulfs cellular constituents indiscriminately, while selective autophagy targets specific proteins or organelles. In plants, stress-induced selective autophagy involves regulators like BES1 and TSPO. The intricate machinery of macro-autophagy in plants, driven by ATG proteins, participates in lipid transfer, phagophore formation, and autophagosome-vacuole fusion. Initiation mechanisms, including ATG9 vesicles, ATG2-ATG18 complexes, and phosphatidylinositol synthase-enriched ER subdomains, are explored. The review scrutinizes autophagy's role in virus infection, emphasizing its protective function against cell death and its dual impact on anti-viral and pro-viral responses. Silencing ATG genes compromise plant immunity, while certain viruses exploit autophagy for infection. Understanding autophagy's regulation informs therapeutic interventions and agricultural applications, highlighting its versatility and essentiality.