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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    • "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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    • "[10], [11], and later on shown to be also required for the biosynthesis of secondary metabolites in the industrially applied fungus Penicillium chrysogenum (e.g. penicillin) and the phytopathogenic fungi Fusarium fujikuroi, F. verticillioides and Cochliobolus heterostrophus, respectively [12]–[15]. Further evidence emerged that LaeA also controls numerous developmental events in fungi, such as conidiation and fruiting body formation [12]–[14]. In plant and human pathogenic fungi, LaeA has also been demonstrated to be a virulence factor [13], [14], [16], [17]. "
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    PLoS ONE 06/2013; 8(6):e67144. DOI:10.1371/journal.pone.0067144 · 3.23 Impact Factor
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    • "Table S2 gives a list of the secondary metabolism clusters up-regulated during incompatibility. Also up-regulated was the ortholog of the Lae1 secondary metabolism regulator characterized in several fungal species (Butchko et al. 2012). "
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