EBR1 genomic expansion and its role in virulence of Fusarium species. (12th December 2013)

• Record Type: Journal Article
• Authors: Jonkers, Wilfried; Xayamongkhon, Henry; Haas, Matthew; Olivain, Chantal; van der Does, H. Charlotte; Broz, Karen; Rep, Martijn; Alabouvette, Claude; Steinberg, Christian; Kistler, H. Corby
• Is Part Of: Environmental microbiology. Volume 16:Number 7(2014:Jul.)
• Page Start: 1982
• Page End: 2003
• Publication Date: 2013-12-12
• Subjects: Microbial ecology -- Periodicals; Environmental Microbiology -- Periodicals; 579.17
• DOI: 10.1111/1462-2920.12331
• Languages: English
• ISSNs: 1462-2912

Abstract

<abstract abstract-type="main"> <title>Summary</title> <p>Genome sequencing of <italic>F</italic><italic>usarium oxysporum</italic> revealed that pathogenic forms of this fungus harbour supernumerary chromosomes with a wide variety of genes, many of which likely encode traits required for pathogenicity or niche specialization. Specific transcription factor gene families are expanded on these chromosomes including the <italic>EBR1</italic> family (Enhanced Branching). The significance of the <italic>EBR1</italic> family expansion on supernumerary chromosomes and whether <italic>EBR1</italic> paralogues are functional is currently unknown. <italic>EBR1</italic> is found as a single copy in <italic>F</italic>.<italic> graminearum</italic> and other fungi but as multiple paralogues in pathogenic <italic>F</italic><italic>. oxysporum</italic> strains. These paralogues exhibit sequence and copy number variation among different host‐specific strains and even between more closely related strains. Relative expression of the <italic>EBR1</italic> paralogues depends on growth conditions and on the presence of the single <italic>EBR1</italic> gene in the core genome. Deletion of <italic>EBR1</italic> in the core genome in different <italic>F</italic><italic>. oxysporum</italic> strains resulted in impaired growth, reduced pathogenicity and slightly reduced biocontrol capacities. To identify genes regulated by <italic>EBR1</italic>, the transcriptomes of wild‐type and Δ<italic>ebr1</italic> strains were compared for both <italic>F</italic><italic>. oxysporum</italic> and <italic>F</italic><italic>. graminearum</italic>. These studies showed that in both species, <italic>EBR1</italic> regulates genes involved in general metabolism as well as virulence.</p> </abstract>