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The PHD Transcription Factor Rum1 Regulates Morphogenesis and Aflatoxin Biosynthesis in Aspergillus flavus.

ABSTRACT: Aspergillus flavus produces mycotoxins especially aflatoxin B? and infects crops worldwide. As a PHD transcription factor, there is no report on the role of Rum1 in the virulence of Aspergillus spp. yet. This study explored the biological function of Rum1 in A. flavus through the construction of rum1 deletion mutants and rum1 complementation strains with the method of homologous recombination. It was found, in the study, that Rum1 negatively regulates conidiation through abaA and brlA, positively regulates sclerotia formation through nsdC, nsdD, and sclR, triggers aflatoxin biological synthesis, and enhances the activity of amylase. Our findings suggested that Rum1 plays a major role in the growth of mycelia, conidia, and sclerotia production along with aflatoxin biosynthesis in A. flavus.

SUBMITTER: Hu Y

PROVIDER: S-EPMC6070901 | biostudies-other | 2018 Jul

REPOSITORIES: biostudies-other

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The PHD Transcription Factor Rum1 Regulates Morphogenesis and Aflatoxin Biosynthesis in Aspergillus flavus.

Hu Yule Y Yang Guang G Zhang Danping D Liu Yaju Y Li Yu Y Lin Guanglan G Guo Zhiqiang Z Wang Shihua S Zhuang Zhenhong Z

Toxins 20180720 7

Aspergillus flavus produces mycotoxins especially aflatoxin B₁ and infects crops worldwide. As a PHD transcription factor, there is no report on the role of Rum1 in the virulence of Aspergillus spp. yet. This study explored the biological function of Rum1 in A. flavus through the construction of rum1 deletion mutants and rum1 complementation strains with the method of homologous recombination. It was found, in the study, that Rum1 negatively regulates conidiati ...[more]

PMID: 30036940

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