Comparative genomics provides a powerful window into ways that nature molds a genome over time. This project builds on previous work supported by the NSF-USDA Microbial Genome Sequencing Program which characterized the genome of the rice blast fungus, Magnaporthe oryzae. The current grant will support comparative analysis of the genome of M. oryzae with its close relatives, Gaeumannomyces graminis var tritici and Magnaporthe poae. G. graminis is the destructive agent of "take-all" disease of domesticated and wild grasses, including wheat, barley, rye and oats. It is also common on turf grasses and can be mistaken for "summer patch" caused by M. poae. Both fungi infect roots through the formation of a specialized structure called a hyphopodia. In contrast, M. oryzae, infects leaf tissue through the formation of an appressorium. The asexual spore states of these fungi also differ. The project objectives are to generate 7X draft genome assemblies for G. graminis var. tritici and M. poae, to generate ESTs from cDNA pools derived from G. graminis var. tritici and M. oryzae using 454 sequencing, to provide a public database for each genome complete with automated gene predictions and annotations and to create a user-friendly genome browser to enable phylogenomic analyses between G. graminis var. tritici, M. poae, and M. oryzae. Comparative genome analyses will enable rigorous evaluation of the genetic and evolutionary basis of structure-functional relationships associated with their different developmental patterns and different disease pathologies caused by these three fungi.
It has been estimated that enough rice is lost to the rice blast fungus to feed tens of millions of people each year. The broader impact of this work is that understanding genome-scale patterns of descent in fungi closely related to rice blast and important plant pathogens in their own right, will reveal important clues to some fundamental recurrent issues in fungal biology, evolution and ecology, such as asexual growth, development and pathological adaptation. This project will have broader impact by providing opportunities for the Magnaporthe and Gaeumannomyces research communities to share their collective expertise and by providing meaningful research experiences for undergraduate students.
