APS Homepage

Poster: Molecular & Cellular Plant-Microbe Interactions: MPMI


Global Analysis of Horizontal Gene Transfer in Fusarium verticillioides
S. GAO (1), J. Wisecaver (2), Y. Zhang (3), L. Ma (3), A. Rokas (2), S. Gold (4), A. Glenn (4) (1) Department of Plant Pathology, University of Georgia, U.S.A.; (2) Department of Biological Sciences, Vanderbilt University, U.S.A.; (3) Department of Bioche

The co-occurrence of microbes within plants and other specialized niches may facilitate horizontal gene transfer (HGT) affecting host-pathogen interactions. We recently identified fungal-to-fungal HGTs involving metabolic gene clusters. For a global analysis of HGTs in the maize pathogen Fusarium verticillioides (Fv), we used a phylogenomic pipeline to identify potential candidates. From an initial output of 1801 genes, manual curation revealed 117 strong HGT candidates acquired mostly from bacteria. Preliminary evaluation suggested several enriched metabolic pathways (e.g. lysine biosynthesis and nitrogen metabolism) compared to the frequency of such genes within the Fv genome. Interestingly, among the five candidates that were categorized as being involved in lysine biosynthesis, FVEG_09873 appears only in Fv and has no orthologs in other fungi. This gene was acquired from plant-associated Proteobacteria and putatively encodes a diaminopimelate epimerase in the diaminopimelic acid pathway employed by most bacteria but not commonly found in fungi. Another promising HGT candidate acquired from bacteria is FVEG_10494 that encodes a putative class-III aminotransferase, functioning in nitrogen metabolism. It is highly expressed when Fv is exposed to nitric oxide. Additional analyses will focus on other HGT candidates having limited fungal distribution. Functional characterization is underway to determine the significance of select HGT candidates in fungal adaptation.