Submitted to: Phytopathology
Publication Type: Abstract Only
Publication Acceptance Date: 3/17/2014
Publication Date: 11/1/2014
Citation: Steward, J.E., Abdo, Z., Glenn, A.E. 2014. Gene clusters FDB1 and FDB2 in Fusarium verticillioides were acquired through multiple horizontal gene transfer events. Phytopathology. 104(Suppl.3):S3.114
Technical Abstract: The corn pathogen Fusarium verticillioides is of significant importance because of its deleterious effects on plant and animal health and on the quality of their products due to mycotoxin contamination. The fungus is known to metabolize antimicrobial compounds produced by corn using genes within two gene clusters, FDB1 and FDB2. Preliminary phylogenetic and genomic synteny data show that the two clusters share an evolutionary history, though not driven by gene duplication and divergence, but rather through horizontal gene transfer (HGT) events between known corn pathogens. We hypothesize that host preference and associated exposure to phytochemicals are driving factors in the evolution of these genomes. Results suggest that F. verticillioides acquired the FDB1 cluster via HGT from Colletotrichum graminicola with near perfect synteny conservation. A separate HGT event is postulated whereby Aspergillus kawachii (or its progenitor) also acquired the FDB1 cluster from C. graminicola but with gene rearrangements. Phylogenetic and synteny data also support that the A. kawachii gene cluster was transferred to F. verticillioides to constitute the FDB2 cluster. Thus, the data suggest that F. verticillioides acquired both clusters from two different fungi by HGT, that the FDB2 genes are themselves derived in part from the FDB1 genes via an earlier, intermediary HGT event involving Aspergillus, and that C. graminicola is the progenitor of all the common FDB1 and FDB2 genes.