VeA Is Associated with the Response to Oxidative Stress in the Aflatoxin Producer Aspergillus flavus

• DOI: 10.1128/ec.00099-14
• Publication Date: 2014-06-21T07:51:26Z
• Authors: Sachin Baidya; Rocio M. Duran; Jessica M. Lohmar; Pamela Y. Harris-...; Jeffrey W. Cary; Sung-Yong Hong; Ludmila V. Roze; John E. Linz; Ana M. Calvo
• Keywords: Transcription; Activating transcription factor; Osmotic shock; Response regulator

ABSTRACT Survival of fungal species depends on the ability these organisms to respond environmental stresses. Osmotic stress or high levels reactive oxygen (ROS) can cause in fungi resulting growth inhibition. Both eukaryotic and prokaryotic cells have developed numerous mechanisms counteract survive presence ROS. In many fungi, HOG signaling pathway is crucial for oxidative response as well osmotic response. This study revealed that while only slightly affected by master regulator veA , this gene, also known control morphological development secondary metabolism species, has a profound effect aflatoxin-producing fungus Aspergillus flavus . We found expression A. homolog genes involved regulated Deletion resulted reduction transcription after exposure hydrogen peroxide. Furthermore, analyses VeA promoters cat1 trxB indicate alters DNA-protein complex formation. particularly notable promoter, where absence results abnormally stronger formation with reduced more sensitivity ROS deletion mutant, suggesting might prevent binding negative regulators promoter. Our positively influences factor gene atfB normal complexes promoter dependent AtfB.