Submitted to: American Phytopathological Society Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: July 31, 2002
Publication Date: N/A
Technical Abstract: Gibberella moniliformis (anamorph Fusarium verticillioides) is one of the most common ear and stalk rot pathogens of maize and can produce carcinogenic mycotoxins called fumonisins. Previous meiotic analyses of G. moniliformis identified three tightly linked fumonisin biosynthetic loci: the Fum1 locus confers ability to produce fumonisins and the Fum2 and Fum3 loci confer ability to hydroxylate fumonisins at carbons 10 and 5, respectively. The goal of this study was to determine whether these meiotically defined Fum loci correspond to any of the 15 molecularly defined FUM genes in a recently identified fumonisin biosynthetic gene cluster. Linkage and transformation-mediated complementation analyses revealed that Fum1 and FUM5, which encodes a polyketide synthase, are the same gene, now designated FUM1. In addition, Fum2-defective strains and a disruption mutant of FUM12, which encodes a putative hydroxylase, have the same fumonisin production phenotype. Therefore, Fum2 and FUM12 are most likely the same gene, now designated FUM2. These results indicate that the Fum loci are located within the fumonisin gene cluster.