Home • Ustilago maydis 521 v2.0
Corn smut (Ustilago maydis), on a maize plant. Image by Jamain used
under the <a
Commons</a> Attribution-Share Alike license via <a
Corn smut (Ustilago maydis), on a maize plant. Image by Jamain used under the Creative Commons Attribution-Share Alike license via Wikimedia Commons

The genome sequence and gene models of Ustilago maydis 521 were not determined by the Joint Genome Institute (JGI), but were provided by Gertrud Mannhaupt and Ulrich Güldener in collaboration with the group of Regine Kahmann in Nov 16, 2017. In order to allow comparative analyses with other fungal genomes sequenced by the JGI, a copy of this genome is incorporated into Mycocosm. JGI tools were used to automatically annotate predicted proteins. Note that this is an updated annotation of the U. maydis version deposited in NCBI, which is also available in MycoCosm.

From the NCBI genome page:

Ustilago maydis, also known as Ustilago zeae, is a basidiomycete fungus that usually exists as a filamentous mycelium in nature. Unlike typical basidiomycetes, it does not have a real fruiting body. During its life cycle it produces a large sac containing resting, diploid teliospores. These spores germinate and form haploid basidiospores by meiosis. Haploid hyphae of opposite mating type can fuse and form a filamentous, dikaryotic cell type. The haploid Ustilago maydis genome is approximately 20.5 Mb, organized in 23 chromosomes. Ustilago maydis is the causal agent of corn smut disease. This fungal pathogen infects growing maize and teosinte plants, leading to the formation of large tumor-like masses filled with spores, stunted plant growth, and reduced crop yield. Corn smut disease causes severe damage and losses of corn, one of the world's major cereal crops, every year. However, in Mexico and Central America, corn smut is considered a culinary delicacy (huitlacoche). Ustilago maydis is an excellent model system for studying host-pathogen interactions, and it has been studied for more than 100 years by plant pathologists. This organism can be cultured easily under laboratory conditions on young corn plants and on synthetic media, where it grows as a single-celled yeast. It is amenable to molecular manipulations, such as transformation and homologous gene replacement. Molecular genetic research with Ustilago maydis focuses on signaling pathways that influence virulence, the role of mating in pathogenesis, and recombination (the Holliday junction, a DNA recombinant structure, was first observed in this species). Recently, the fungus has emerged as an excellent experimental model for the molecular genetic analysis of phytopathogenesis, particularly in the characterization of infection-specific morphogenesis in response to signals from host plants. Ustilago maydis also serves as an important model for other basidiomycete plant pathogens that are more difficult to work with in the laboratory, such as the rust and bunt fungi. The genomic sequence of Ustilago maydis will be valuable in comparative analyses with other fungal genomes, especially for understanding the host range of fungal phytopathogens. It will also aid in identifying molecular targets for the development of antifungal drugs. The analysis of Ustilago maydis will provide a framework for studying the hundreds of other Ustilago species that attack important crops, such as barley, wheat, sorghum, and sugarcane.

Genome Reference(s)