ARS | Publication request: Altered expression of polyketide biosynthetic gene clusters in fumonisin-deficient mutants of Fusarium verticillioides

Submitted to: Meeting Abstract
Publication Type: Abstract
Publication Acceptance Date: June 17, 2008
Publication Date: July 4, 2008
Citation: Butchko, R.A., Brown, D.W., Proctor, R., Busman, M., Woloshuk, C.P., Bluhm, B.H., Kim, H. 2008. Altered expression of polyketide biosynthetic gene clusters in fumonisin-deficient mutants of Fusarium verticillioides [abstract]. Gordon Research Conference on Cellular and Molecular Fungal Biology.

Technical Abstract: Fusarium verticillioides is a pathogen of maize and produces fumonisins, a group of polyketide derived secondary metabolites. Fumonisins cause diseases in animals, and they have been correlated epidemiologically with esophageal cancer and birth defects in humans. Fumonisin biosynthetic genes are clustered on chromosome I, and their expression is co-regulated. In addition to a regulatory gene located in the cluster, genes elsewhere in the genome have been shown to affect fumonisin production. The availability of the F. verticillioides genome sequence has facilitated the identification of 14 polyketide synthase (PKS) genes in addition to the fumonisin biosynthetic PKS gene FUM1. The roles of most of these PKS genes have yet to be determined. DNA microarray experiments have revealed co-expression of some of the PKS genes with their flanking genes, suggesting that the PKS and flanking genes are polyketide biosynthetic gene clusters. Here, microarray analysis revealed that some of the PKS genes are differentially expressed in fumonisin-deficient mutants and wild-type F. verticillioides. These results are being used to identify the metabolite(s) synthesized by the enzymes encoded by the gene clusters and to elucidate the biological role of the metabolites.