Submitted to: American Phytopathological Society
Publication Type: Abstract Only
Publication Acceptance Date: May 1, 2005
Publication Date: July 30, 2005
Citation: Alexander, N.J., Mc Cormick, S.P., Larson, T.M., Proctor, R.H., Desjardins, A.E. 2005. Genetic control of trichothecene biosynthesis in fusarium. American Phytopathological Society. 95(6):S124. Technical Abstract: The biosynthesis of trichothecenes involves a complex pathway that begins with the sesquiterpene hydrocarbon trichodiene and consists of multiple oxygenation, cyclization, and esterification steps. Twelve genes required for trichothecene biosynthesis in Fusarium are clustered within a 26-kb segment of DNA. However, several other biosynthetic and regulatory genes are located elsewhere in the genome. While many of the gene functions have been determined by mutational disruption, a few have been elucidated by a transgenic expression system. The regulation of trichothecene biosynthesis is not well understood. Two genes, Tri10 and Tri6, required for Tri gene expression and a third gene, Tri15, required for suppression of these genes, have been identified. Tri6 encodes a transcriptional factor that binds to specific nucleotide motifs within the promoters of other Tri genes, while Tri10 and Tri15 encode proteins whose method of regulation of gene expression is not known. Since trichothecene production by F. graminearum is necessary for virulence on wheat, elucidation of factors that regulate this production may lead to novel methods for the control of wheat head blight.