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

Abstract

<i>Aspergillus flavus</i> 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 <i>Aspergillus</i> spp. yet. This study explored the biological function of Rum1 in <i>A. flavus</i> through the construction of <i>rum1</i> deletion mutants and <i>rum1</i> complementation strains with the method of homologous recombination. It was found, in the study, that Rum1 negatively regulates conidiation through <i>abaA</i> and <i>brlA</i>, positively regulates sclerotia formation through <i>nsdC</i>, <i>nsdD</i>, and <i>sclR</i>, 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 <i>A. flavus</i>.