AGRICULTURAL PRACTICES, ECOLOGICAL AND VARIETAL EFFECTS ON AFLATOXINS AND OTHER MYCOTOXINS IN CORN
Location: Biological Control of Pests Research Unit
Title: FvVE1 Regulates Biosynthesis of the Mycotixins and Fumonisins and Fusarims verticillioides
Submitted to: Journal of Agriculture and Food Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: April 6, 2009
Publication Date: April 22, 2009
Citation: Myung, K., Li, S., Butchko, R.A., Busman, M., Proctor, R., Abbas, H.K., Calvo, A.M. 2009. FvVE1 Regulates Biosynthesis of the Mycotixins and Fumonisins and Fusarims verticillioides. Journal of Agriculture and Food Chemistry. 57(11):5089-94
Interpretive Summary: A mold named Fusarium verticillioides causes a disease in corn called Fusarium ear rot and produces potent toxins such as fumonisins and others. Corn is often contaminated with mold and toxins that cause economic losses for corn growers, especially in the Mid-South. This study reports a strategy to control toxins produced by this mold (Fusarium verticillioides) by deleting the gene FvVE1 which is crucial to production of toxins by the mold. This research will enable scientists and the corn industry to find ways to use this technology to stop the mold from producing these compounds in corn and other products. This gene is present in other molds, including Aspergillus, which produces the most dangerous toxin in corn called aflatoxin. Therefore, this study has implications that may be useful to control a variety of important toxins that cause disease in animals and human and large economic losses, especially in the Mid-South region.
The veA homologous genes positively regulate sterigmatocystin in Aspergillus nidulans and aflatoxin production in A. parasiticus and A. flavus. Whether veA homologs have a role in regulating secondary metabolism in other fungal genera is unknown. In this study, we examined the role of the veA homologous gene FvVE1 on the production of two different toxins in the important plant pathogen F. verticillioides. We found that deletion of FvVE1 completely suppressed fumonisin production on two natural substrates, corn and rice, while it only reduced fumonisin production in the complex liquid medium GYAM. Deletion of FvVE1 also reduced the yield of bikaverin in GYAM, though an increase in bikaverin production was detected on the natural corn media. These effects of FvVE1 deletion on toxin production were found to be the same in two separate mating types. Complemented strains restored the production of both fumonisins and bikaverin to wild-type levels. Our results strongly suggest that FvVE1 differentially regulates fumonisin and bikaverin biosynthesis in a medium-dependent manner.