The Stress Response Regulator AflSkn7 Influences Morphological Development, Stress Response, and Pathogenicity in the Fungus Aspergillus flavus

Toxins (Basel). 2016 Jul 5;8(7):202. doi: 10.3390/toxins8070202.

Abstract

This study focused on AflSkn7, which is a stress response regulator in the aflatoxin-producing Aspergillus flavus. The ΔAflSkn7 mutants exhibited partially defective conidial formation and a complete inability to generate sclerotia, indicating AflSkn7 affects A. flavus asexual and sexual development. The mutants tolerated osmotic stress but were partially susceptible to the effects of cell wall stress. Additionally, the ΔAflSkn7 mutants were especially sensitive to oxidative stress. These observations confirmed that AflSkn7 influences oxidative stress responses rather than osmotic stress responses. Additionally, AflSkn7 was observed to increase aflatoxin biosynthesis and seed infection rates. These results indicate AflSkn7 affects A. flavus morphological development, stress response, aflatoxin production, and pathogenicity. The results of this study may facilitate the development of new methods to manage A. flavus infections.

Keywords: Aspergillus flavus; aflatoxins; development; pathogenicity; stress response.

MeSH terms

  • Aflatoxins / biosynthesis
  • Aspergillus flavus / genetics
  • Aspergillus flavus / growth & development
  • Aspergillus flavus / metabolism*
  • Aspergillus flavus / pathogenicity
  • Fungal Proteins / genetics
  • Fungal Proteins / metabolism*
  • Mutation
  • Osmotic Pressure
  • Oxidative Stress*
  • Virulence

Substances

  • Aflatoxins
  • Fungal Proteins
  • Skn7 protein, Aspergillus flavus