Ustilago maydis is the dimorphic fungal pathogen that causes corn smut disease. The purpose of this research was to identify novel genes important for disease development by analyzing a collection of filamentation suppressor mutants, characterizing the morphologically regulated gene termed uhf1 (upregulated in hyphal form), and amplifying cap1 (cyclase associated protein) from U. maydis for future functional studies. Using molecular complementation, a total of 29 filamentation suppressor mutants were evaluated for filamentous growth. While a few strains were recalcitrant to standard methodologies, 20 strains were complemented either by ubc1, ubc2, ubc3, ubc4, ubc5, or hgl1. Gene disruption was used to investigate the role of uhf1 on morphology, mating, and pathogenicity. Studies indicated that uhf1 is necessary for maintaining a wild-type morphology, pigmentation, and growth rate, but is not essential for mating, gall production, or teliospore development. Polymerase Chain Reaction (PCR) was employed to amplify cap1 from U. maydis.
