Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: August 3, 2011
Publication Date: September 4, 2012
Citation: McCormick, S.P., Alexander, N.J., Proctor, R. 2012. Trichothecene triangle: toxins, genes, and plant disease. In: Gang, D.R. editor. Phytochemicals, Plant Growth, and the Environment. New York, NY: Springer Science+Business Media. p. 1-17. Technical Abstract: Trichothecenes are a family of sesquiterpene epoxides that inhibit eukaryotic protein synthesis. These mycotoxins are produced in Fusarium-infested grains such as corn, wheat, and barley, and ingestion of contaminated grain can result in a variety of symptoms including diarrhea, hemorrhaging and feed refusal. Biochemical and genetic investigations have characterized the genes controlling trichothecene biosynthesis. In Fusarium, trichothecene genes have been mapped to three loci including a 26 kb cluster of twelve genes. Production of trichothecenes by Fusarium graminearum has been shown to be an important virulence factor in wheat head scab. Strains of F. graminearum have been categorized into three different chemotypes, nivalenol (NIV), 3-acetyldeoxynivalenol (3ADON), and 15-acetyldeoxynivalenol (15ADON), based on polymorphisms seen using specific PCR primers. Although 15ADON strains predominate in North America, there has been a recent emergence of 3ADON and NIV-producing strains. The genetic basis for these chemotypes has been elucidated with sequence analysis, genetic engineering and heterologous expression of trichothecene biosynthetic genes.