Possible role of autophagy in microbial volatile pollutant-induced starch degradation and expression of hypoxia responsive genes

Chung-Chih Huang; Ching-Han Chang; Tu-Trinh Thi Truong; Wu-Guei Wang; Che Hui Lin; Chih-Yun Chiang; Iwai Obayashi; Hao-Jen Huang

doi:10.1016/j.envpol.2025.125663

Possible role of autophagy in microbial volatile pollutant-induced starch degradation and expression of hypoxia responsive genes

Environ Pollut. 2025 Jan 9:125663. doi: 10.1016/j.envpol.2025.125663. Online ahead of print.

Authors

Chung-Chih Huang¹, Ching-Han Chang², Tu-Trinh Thi Truong³, Wu-Guei Wang⁴, Che Hui Lin⁵, Chih-Yun Chiang⁶, Iwai Obayashi⁷, Hao-Jen Huang⁸

Affiliations

¹ Department of Life Sciences, National Cheng Kung University, Tainan, Taiwan. Electronic address: [email protected].
² Graduate Program in Translational Agricultural Sciences, National Cheng Kung University and Academia Sinica, Taiwan. Electronic address: [email protected].
³ Department of Life Sciences, National Cheng Kung University, Tainan, Taiwan; Faculty of Technology, The University of Danang-Campus in Kontum, The University of Danang, Kon Tum City, Vietnam. Electronic address: [email protected].
⁴ Institute of Tropical Plant Sciences and Microbiology, National Cheng Kung University, Tainan, Taiwan. Electronic address: [email protected].
⁵ Department of Life Sciences, National Cheng Kung University, Tainan, Taiwan. Electronic address: [email protected].
⁶ Department of Life Sciences, National Cheng Kung University, Tainan, Taiwan. Electronic address: [email protected].
⁷ Department of Life Sciences, National Cheng Kung University, Tainan, Taiwan. Electronic address: [email protected].
⁸ Department of Life Sciences, National Cheng Kung University, Tainan, Taiwan; Graduate Program in Translational Agricultural Sciences, National Cheng Kung University and Academia Sinica, Taiwan; Institute of Tropical Plant Sciences and Microbiology, National Cheng Kung University, Tainan, Taiwan. Electronic address: [email protected].

PMID: 39798790
DOI: 10.1016/j.envpol.2025.125663

Abstract

Autophagy is thought to be critically involved in the regulation of nutrient metabolism and gene expression. Nevertheless, little is known about its role in regulating starch metabolism and hypoxia responsive genes in plants exposed to microbial volatile pollutants. In the present study, we found that exposure of Arabidopsis to Enterobacter aerogene (E. aerogene) volatile pollutants induced autophagy, as indicated by autophagosome formation. The exposure also caused upregulation of autophagy-associated genes, such as ATGs, NBR1, ATI1, and ATG8e-regulating transcription factors. Additionally, exposure to E. aerogenes volatile pollutants induced starch degradation in the roots of Arabidopsis seedlings. Finally, we found that ATG7-deficiency negatively affected the expression of hypoxia-responsive genes (i.e HRE1, HRA1, and ADH1) and starch degradation induced by E. aerogenes volatile pollutants. Overall, our study reveals that microbial volatile pollutants can induce starch degradation and autophagy, which participates in the regulation of some hypoxia-responsive genes and starch metabolism. These findings help to define the role of autophagy in plant nutrient metabolism and regulation of gene expression under microbial volatile pollutant exposure. The insights gained may contribute to agricultural management when living organisms face challenges from microbial volatile pollutants.

Keywords: Enterobacter aerogenes; autophagy; hypoxia responsive genes; starch degradation; volatile pollutant.