Location: Toxicology & Mycotoxin ResearchTitle: Genome-wide identification of horizontal gene transfer in Fusarium verticillioides
|GAO, SHAN - University Of Georgia|
|WISECAVER, JENNIFER - Vanderbilt University|
|ZHANG, YONG - University Of Massachusetts|
|MA, LI-JUN - University Of Massachusetts|
|ROKAS, ANTONIS - Vanderbilt University|
|Glenn, Anthony - Tony|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 12/8/2016
Publication Date: 3/14/2017
Citation: Gao, S., Wisecaver, J.H., Zhang, Y., Ma, L., Rokas, A., Gold, S.E., Glenn, A.E. 2017. Genome-wide identification of horizontal gene transfer in Fusarium verticillioides. Meeting Abstract. Meeting Book only.
Interpretive Summary: Organisms are able to acquire genetic information from their surroundings and other species with which they make contact. This is called horizontal gene transfer or HGT. This work devised and used a computer pipeline to identify genes with signatures of HGT in the mycotoxigenic corn pathogen, Fusarium verticillioides (Fv). The focus here was on genes likely acquired from bacteria. One hundred and seventeen genes were identified as strong candidates for acquisition by Fv from bacteria. A number of these genes fall into several discrete metabolic pathways. One gene, FVEG_09873, is unique in fungi and appears to be inherited from Proteobacteria. A second gene, FVEG_10494, is also likely of bacterial origin and may be involved in nitrogen metabolism. Deletion mutants of FVEG_10494 are being analyzed for its role in the biology of the fungus.
Technical Abstract: Horizontal gene transfer (HGT), the exchange and stable integration of genetic material between different lineages, breaks species boundaries and generates new biological diversity. In eukaryotes, despite potential barriers, like the nuclear envelope and multicellularity, HGT may be facilitated by the intimate contact between organisms and other strategies. Intrigued by the potential role of HGT in the evolution and adaptation of the maize pathogen Fusarium verticillioides (Fv), we applied a phylogenomic pipeline to identify potential HGT candidates in the genome of Fv. From an initial output of 1801 genes, manual curation revealed 117 strong HGT candidates, which tend to be intronless, non-plastid-derived, and bacteria-acquired. Functional category analysis suggested several enriched metabolic pathways (e.g. lysine biosynthesis and nitrogen metabolism) compared to the general frequency of such genes within the Fv genome. Interestingly, among the five candidates that were categorized as being involved in lysine biosynthesis, FVEG_09873 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, further supporting the bacterial origin of this candidate. Another promising HGT candidate acquired from bacteria is FVEG_10494 that encodes a putative class-III aminotransferase, functioning in nitrogen metabolism. Additional analyses will focus on other HGT candidates having limited fungal distribution. Transcriptional profiling and functional characterization are underway to determine the significance of select HGT candidates on the fitness, virulence, and physiological responses of Fv.