An emerging role of non-canonical conjugation of ATG8 proteins in plant response to heat stress

ABSTRACT

Members of the ATG8 (autophagy-related protein 8) protein family can be non-canonically conjugated to single membrane-bound organelles. The exact function of ATG8 on these single membranes remains poorly understood. Recently, using Arabidopsis thaliana as a model system, we identified a non-canonical conjugation of ATG8 pathway involved in the reconstruction of the Golgi apparatus upon heat stress. Short acute heat stress resulted in rapid vesiculation of the Golgi, which was accompanied with the translocation of ATG8 proteins (ATG8a to ATG8i) to the dilated cisternae. More importantly, we found that ATG8 proteins can recruit clathrin to facilitate Golgi reassembly by stimulating the budding of ATG8-positive vesicles from dilated cisternae. These findings provide new insight into one of the possible functions of ATG8 translocation onto single membrane organelles, and will contribute to a better understanding of non-canonical conjugation of ATG8 in eukaryotic cells.

Abbreviations: ADS, AIMs docking site; AIM, ATG8-interacting motif; ATG, autophagy-related; CLC2, Clathrin light chain 2; ConcA, concanamycin A; HS, heat stress; PE, phosphatidylethanolamine; PM, plasma membrane; PS, phosphatidylserine; TGN, trans-Golgi network; V-ATPase, vacuolar-type ATPase

KEYWORDS:

• ATG8
• clathrin
• Golgi
• heat stress
• non-canonical autophagy
• vacuole

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by grants from the National Natural Science Foundation of China (32061160467, 32270291, 31870171) and Fok Ying-Tong Education Foundation for Young Teachers in the Higher Education Institutions of China (171014) to CG, the National Science Foundation of China (31600288) and the Basic Research Program of Guangzhou (202201010508) to JZ