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Updated: Mar 6, 2026
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Affinity Precipitation of Active Rho-GEFs Using a GST-tagged Mutant Rho Protein GST-RhoAG17A from Epithelial Cell Lysates
Published on: March 31, 2012
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Rho GTPase RhoD interacts with the Rho GEF Bud3 and is involved in aflatoxin biosynthesis, cell wall integrity, and
Jia Xu1, Yanyan Zhang1, Junhe Ren1
1School of Food Science and Engineering, Ocean University of China, Qingdao 266404, China.
Microbiological Research
|March 4, 2026
Summary
The RhoD protein is crucial for Aspergillus flavus growth, aflatoxin production, and pathogenicity. Its absence impairs key fungal development and virulence factors, offering targets for controlling this food safety threat.
Area of Science:
- Mycology
- Molecular Biology
- Plant Pathology
Background:
- Aspergillus flavus is an opportunistic pathogen producing carcinogenic aflatoxins, threatening food safety, agriculture, and public health.
- Aflatoxins pose significant risks, necessitating research into the molecular mechanisms governing A. flavus growth and toxin production.
Purpose of the Study:
- To investigate the role of RhoD, a molecular switch, and its guanine nucleotide exchange factor Bud3 in Aspergillus flavus.
- To elucidate the impact of RhoD on aflatoxin biosynthesis, pathogenicity, and cellular processes in A. flavus.
Main Methods:
- Genetic analysis involving gene deletion mutants (ΔrhoD, Δbud3).
- Multi-omics analysis (gene expression, metabolomics) and indicator assays.
- Phenotypic characterization including conidia formation, sclerotia production, and pathogenicity assays in peanut and corn.
Main Results:
- Loss of rhoD or bud3 resulted in defective conidia formation, no sclerotia, reduced aflatoxin biosynthesis, and decreased pathogenicity.
- ΔrhoD mutant showed downregulated aflatoxin biosynthetic genes and reduced precursor metabolites.
- RhoD influences organic acid secretion, ROS homeostasis, lipid metabolism, cell wall integrity, and response to external stimuli.
Conclusions:
- RhoD plays a vital role in Aspergillus flavus growth, aflatoxin production, and pathogenicity.
- Understanding RhoD's function provides insights for developing strategies to control A. flavus and mitigate aflatoxin contamination.
- RhoD's involvement in cell wall integrity and response mechanisms highlights its importance in fungal pathogenesis.
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