|Kistler, H - Corby|
Submitted to: National Fusarium Head Blight Forum Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: 12/13/2003
Publication Date: 12/13/2003
Citation: Seong, K., Zhao, X., Tracy, M., Trail, F., Kistler, H.C., Xu, J. 2003. Identifying virulence factors in Fusarium graminearum using forward and reverse genetics [abstract]. National Fusarium Head Blight Forum Proceedings, December 12-15, 2003, Bloomington, Minnesota. p. 176. Interpretive Summary:
Technical Abstract: Fusarium head blight or scab caused by Fusarium graminearum is a destructive disease on wheat and barley. Infested cereals are reduced in yield and contaminated with harmful mycotoxins. A molecular approach to the study of F. graminearum is critical because there are no effective fungicides and highly resistant plant varieties for controlling scab. Our goal is to determine molecular mechanisms of fungal pathogenesis in F. graminearum. In the past few years, we have generated over 9,000 REMI (restriction-enzyme mediated integration) transformants and identified 14 mutants defective in plant infection. One objective of this research is to generate randomly tagged mutant populations and characterize the genes disrupted in these REMI mutants that are reduced in virulence or are nonpathogenic. Genes that have been recovered to date include the HMG-CoA reductase and cystathionine beta-lyase genes. Further characterization of these genes will be discussed. We also have generated over 10,000 ESTs and 10x coverage of F. graminearum genome sequence in collaboration with the Whitehead Genome Research Institute at MIT. As a pilot test for large scale functional analyses in F. graminearum, over 15 candidate genes have been selected for targeted gene disruption or replacement. These genes are either homologous to known fungal virulence factors or predicted to be involved in various fungal developmental processes or secondary metabolism, such as polyketide synthases and signaling components. Phenotypes of mutants deleted of specific genes will be presented. Overall, both reverse and forward genetic approaches were found to be useful for identifying genes important for F. graminearum pathogenesis. The creation of a mutant population and functional analysis approaches developed in these studies will be useful resources for pursuing systematic characterization of F. graminearum-wheat interactions at the genome level.