英文摘要: | Fungi comprise one of the most successful groups of life on Earth. They inhabit most of the world's environments, where they perform numerous functions (e.g., nutrient cycling, foundations of food webs, etc.) that are central to healthy ecosystems. Importantly, fungi interact with all other forms of life, including plants, animals and bacteria -- in associations that range from beneficial to antagonistic. Zygomycete fungi, the focus of this research project, are an ancient group in which most of the morphological and ecological traits associated with Kingdom Fungi first arose, but their evolutionary history and ecological associations have not yet been well resolved. This project will reconstruct the genealogical relationships of this earliest branch in fungal evolutionary history, resolve the origins of symbiotic relationships between plants and zygomycetes, reveal how complex body plans evolved in the group, elucidate mechanisms of mating genetics between organisms with complex and differing life cycles, and develop genomic barcodes to facilitate identification of unknown fungi. The results of this research will contribute to many scientific disciplines and to society. Expanding and maintaining expertise on these fungi is critical for the field of biology, human health and productivity, and safe food production. This project includes training of the next generation of mycologists, dissemination of information on basic fungal biology, development of teaching resources, expansion of biological database and web resources, development of research materials including strain cultures and genomes for the wider scientific community, and broadening of participation of underrepresented groups in STEM disciplines.
Zygomycetes are filamentous fungi that lack flagella and that produce simple but defined reproductive structures. An initial analysis of zygomycete genomes support the hypothesis that the group is a pivotal transition point between certain flagellated Fungi and their specific life histories, and what became the dominant eukaryotic terrestrial clade of Fungi (the fleshy fungi, e.g., mushrooms). Because the zygomycetes are the first terrestrial fungi that exhibit fruiting bodies, understanding how these structures evolved will provide a basis for understanding the origins of complex morphogenesis (e.g., multicellularity) in the Fungi, as well as the evolution of complex life histories. Zygomycetes also display a diversity of ecological relationships with plants (mycorrhizae), animals (pathogens) and bacteria (endosymbionts). Resolving the phylogenetic origins of these interactions will provide an evolutionary framework for elucidating molecular and biochemical mechanisms that govern these interactions, and in doing so, will have direct impacts on research into natural and managed ecosystems and human welfare. This research will also refine molecular environmental sampling techniques, resulting in a more accurate census of zygomycete biodiversity, especially in soil ecosystems. By gathering orders of magnitude more genome-scale data and integrating it with biochemical, morphological, subcellular, and fossil data layers, this elusive region of the fungal genealogy of life will be illuminated and will provide a foundation for broad scale biological research. |