Autophagy-related gene ATG7 participates in the asexual development, stress response and virulence of filamentous insect pathogenic fungus Beauveria bassiana

  • Hai-Yan Lin
  • Jia-Jia Wang
  • Ming-Guang Feng
  • Sheng-Hua YingEmail author
Original Article


Autophagy is a sophisticated mechanism for maintaining cellular homeostasis, in which E1-like enzyme (ATG7) controls the activation of ubiquitin-like conjugation system in the autophagy pathway. In the insect pathogenic fungus Beauveria bassiana, a yeast ortholog of ATG7 was identified and functionally analyzed. Ablation of BbATG7 gene blocks the autophagic process under starvation stress. The mutant ΔBbATG7 exhibited impaired growth on the media with chitin as single nitrogen source. On rich media, gene loss did not cause notable effect on vegetative growth, but resulted in a considerable reduction in conidiation (71.6%) and blastospore yield (61.1%) in the mutant. In addition, the ΔBbATG7 mutant displayed increased sensitivity to stress caused by menadione and Congo red. The virulence of ΔBbATG7 mutant was significantly attenuated as indicated in topical and intrahemocoel injection assays. Our study indicates that BbATG7 contributes to B. bassiana virulence via regulating autophagy pathway and playing non-autophagic functions in the infection cycle.


Autophagy-related gene 7 Asexual development Stress tolerance Virulence Beauveria bassiana 



This study was jointly supported by the Zhejiang Provincial Natural Science Foundation of China under Grant No. LZ19C140001 and the National Natural Science Foundation of China (31670144).

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Supplementary material

294_2019_955_MOESM1_ESM.pdf (124 kb)
Supplementary material 1 (PDF 123 KB)


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Institute of Microbiology, College of Life SciencesZhejiang UniversityHangzhouChina

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