Advances in research on autophagy in the maintenance of insect–microbe symbiosis

Abstract Autophagy, as a crucial intracellular degradation mechanism, plays an indispensable role in maintaining insect–microbe symbiosis through bidirectional regulation. Microorganisms can inhibit insect autophagy to facilitate their colonization and proliferation by activating the target of rapamycin pathway and suppressing Atg gene expression. Alternatively, they can induce autophagy to promote host nutrient absorption by activating the AMPK pathway and secreting effector molecules. Insects, in turn, utilize autophagy to clear excessively proliferating symbionts and invading pathogens while selectively retaining beneficial symbiotic bacteria through specific mechanisms. The functions of autophagy in nutrient exchange, immune defense, and developmental regulation provide an important theoretical basis for elucidating the evolution and stability of insect–microbe symbiotic relationships. Future research should focus on nonmodel insects, the cross‐regulation between autophagy and other cellular processes, autophagy mechanisms from an evolutionary biology perspective, and the application prospects in pest control and beneficial insect cultivation.