The membrane mucin Msb2 regulates aflatoxin biosynthesis and pathogenicity in fungus Aspergillus flavus. Issue 2 (7th November 2020)

• Record Type: Journal Article
• Authors: Qin, Ling; Li, Ding; Zhao, Jiaru; Yang, Guang; Wang, Yinchun; Yang, Kunlong; Tumukunde, Elisabeth; Wang, Shihua; Yuan, Jun
• Other Names: Zhou Ning‐Yi guestEditor.; Huang Wei guestEditor.; Bai Linquan guestEditor.; Yang Chen guestEditor.; Wang Hui guestEditor.
• Is Part Of: Microbial biotechnology. Volume 14:Issue 2(2021)
• Page Start: 628
• Page End: 642
• Publication Date: 2020-11-07
• Subjects: Microbial biotechnology -- Periodicals; Biotechnology; Microbiology; 660.62
• DOI: 10.1111/1751-7915.13701
• Languages: English
• ISSNs: 1751-7915

Abstract

Summary: As a pathogenic fungus, Aspergillus flavus can produce carcinogenic aflatoxins (AFs), which poses a great threat to crops and animals. Msb2, the signalling mucin protein, is a part of mitogen‐activated protein kinase (MAPK) pathway which contributes to a range of physiological processes. In this study, the roles of membrane mucin Msb2 were explored in A. flavus by the application of gene disruption. The deletion of msb2 gene (Δ msb2 ) caused defects in vegetative growth, sporulation and sclerotia formation when compared to WT and complement strain (Δ msb2 C ) in A. flavus . Using thin‐layer chromatography (TLC) and high‐performance liquid chromatography (HPLC) analysis, it was found that deletion of msb2 down‐regulated aflatoxin B1 (AFB1 ) synthesis and decreased the infection capacity of A. flavus . Consistently, Msb2 responds to cell wall stress and osmotic stress by positively regulating the phosphorylation of MAP kinase. Notably, Δ msb2 mutant exhibited cell wall defect, and it was more sensitive to inhibitor caspofungin when compared to WT and Δ msb2 C . Taking together, these results revealed that Msb2 plays key roles in morphological development process, stresses adaptation, secondary metabolism and pathogenicity in fungus A. flavus . Abstract : Msb2 is important for growth, conidia and sclerotia formation in Aspergillus flavus . Msb2 play negative roles in regulation of aflatoxins biosynthesis.