Lae1 regulates expression of multiple secondary metabolite gene clusters in Fusarium verticillioides

National Center for Agricultural Utilization Research, Peoria, IL, United States.
Fungal Genetics and Biology (Impact Factor: 2.59). 06/2012; 49(8):602-12. DOI: 10.1016/j.fgb.2012.06.003
Source: PubMed


The filamentous fungus Fusarium verticillioides can cause disease of maize and is capable of producing fumonisins, a family of toxic secondary metabolites linked to esophageal cancer and neural tube defects in humans and lung edema in swine and leukoencephalomalacia in equines. The expression of fumonisin biosynthetic genes is influenced by broad-domain transcription factors (global regulators) and Fum21, a pathway-specific transcription factor. LaeA is a global regulator that in Aspergillus nidulans, affects the expression of multiple secondary metabolite gene clusters by modifying heterochromatin structure. Here, we employed gene deletion analysis to assess the effect of loss of a F. verticillioides laeA orthologue, LAE1, on genome-wide gene expression and secondary metabolite production. Loss of Lae1 resulted in reduced expression of gene clusters responsible for synthesis of the secondary metabolites bikaverin, fumonisins, fusaric acid and fusarins as well as two clusters for which the corresponding secondary metabolite is unknown. Analysis of secondary metabolites revealed that, in contrast to a previously described Fusarium fujikuroi lae1 mutant, bikaverin production is reduced. Fumonisin production is unchanged in the F. verticillioides lae1 mutant. Complementation of the F. verticillioides mutant resulted in increased fumonisin production.

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Available from: Philipp Wiemann, Aug 11, 2014
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    • "Roche NimbleGen (Iceland) conducted microarray hybridizations , data acquisition, and initial analysis. Microarrays were designed based on genomic and EST datasets as previously described[25,26]. Normalized data were compared using DNAS- TAR ArrayStar v5.0 analysis software (Madison, WI, USA). "
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    ABSTRACT: Microbes encounter a broad spectrum of antimicrobial compounds in their environments and often possess metabolic strategies to detoxify such xenobiotics. We have previously shown that Fusarium verticillioides, a fungal pathogen of maize known for its production of fumonisin mycotoxins, possesses two unlinked loci, FDB1 and FDB2, necessary for detoxification of antimicrobial compounds produced by maize, including the γ-lactam 2-benzoxazolinone (BOA). In support of these earlier studies, microarray analysis of F. verticillioides exposed to BOA identified the induction of multiple genes at FDB1 and FDB2, indicating the loci consist of gene clusters. One of the FDB1 cluster genes encoded a protein having domain homology to the metallo-β-lactamase (MBL) superfamily. Deletion of this gene (MBL1) rendered F. verticillioides incapable of metabolizing BOA and thus unable to grow on BOA-amended media. Deletion of other FDB1 cluster genes, in particular AMD1 and DLH1, did not affect BOA degradation. Phylogenetic analyses and topology testing of the FDB1 and FDB2 cluster genes suggested two horizontal transfer events among fungi, one being transfer of FDB1 from Fusarium to Colletotrichum, and the second being transfer of the FDB2 cluster from Fusarium to Aspergillus. Together, the results suggest that plant-derived xenobiotics have exerted evolutionary pressure on these fungi, leading to horizontal transfer of genes that enhance fitness or virulence.
    Full-text · Article · Jan 2016 · PLoS ONE
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    • "Analysis of SMs in the F . verticillioides LAE1 mutant revealed differences of regulation from that of in F . fujikuroi LAE1 mutant ( Wiemann et al . , 2010 ) as bikaverin production was reduced , but the amount of fumonisin B1 ( FB1 ) ( Figure 3 ) remained unchanged ( Butchko et al . , 2012 ) . Nitrogen limitation have appeared to be an essential stimulus for the activation of virulence functions in phytopathogenic fungi . The ability to metabolize a wide variety of nitrogen sources enables fungi to colonize different environmental niches and survive nutrient limitations ( Tudzynski , 2014 ) . Amino acids are required for "
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