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Functional analysis of the exocyst subunit BcExo70 in Botrytis cinerea

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Abstract

Botrytis cinerea is one of the most important saprophytic plant pathogenic fungi. The exocyst complex and exocytosis was demonstrated to be involved in fungal development and plant infection. Here, we investigated the function of an exocyst subunit gene Bcexo70 in B. cinerea. The results show that knockout of the Bcexo70 gene significantly reduced the fungal growth and hindered the production of conidia and sclerotia. The Bcexo70 deletion strains showed a severe decrease in virulence toward tomato leaves and reduced secretion of cell wall-degrading enzyme. Confocal and electronic microscopic observation showed that the vesicles in the Bcexo70 mutants were enlarged and scattered in the cytoplasm compared to the regular distribution in the hyphal tip in wild-type strain. This study showed that the exocyst gene Bcexo70 is crucial for fungal growth, conidiation and pathogenicity in B. cinerea.

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Acknowledgements

This work was supported by the Natural Science Foundation of Zhejiang Province (LY18C140005).

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Correspondence to Weixia Wang or Kun Wang or Tingheng Zhu.

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Guan, W., Feng, J., Wang, R. et al. Functional analysis of the exocyst subunit BcExo70 in Botrytis cinerea. Curr Genet 66, 85–95 (2020). https://doi.org/10.1007/s00294-019-01002-9

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Keywords

  • Botrytis cinerea
  • Exocyst
  • exo70
  • Vesicle
  • Pathogenicity