Becoming a fungus: comparative phylogenomic studies of evolution of hyphal growth and absorptive nutrition in fungi

成为真菌：真菌菌丝生长和吸收性营养进化的比较系统发育学研究

• 批准号: 138427-2011
• 负责人: Berbee, Mary
• 金额: $ 3.35万
• 依托单位: University of British Columbia
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2014
• 资助国家: 加拿大
• 起止时间: 2014-01-01 至 2015-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=545532
• 关键词: Becoming; fungus; comparative; phylogenomic; studies

Fungi can cause plant diseases, serve as mycorrhizal partners, and decompose litter and woody debris, all because of the tubular hyphae (filaments of cells, surrounded by a cell wall) that make up their bodies. Hyphae poke and penetrate into substrates while secreting digestive enzymes across their complex cell walls. The enzymes digest organic compounds into simple, diffusible molecules, which fungi absorb to fuel their growth, making fungi the most important terrestrial eukaryotic saprotrophs. However, phylogenetic evidence shows fungi and animals share a common ancestor and the earliest fungi were unicellular not hyphal; wall-less and probably phagotrophic instead of ingesting nutrients across a cell wall; and aquatic and with a flagellated stage rather than terrestrial. Reconstructing evolution of hyphal construction, secreted digestive enzymes, and terrestrial growth, are main themes of the proposed research. We will take advantage of seven new genome sequences for early-diverging fungi, the result of our successful community sequencing proposal to the US Joint Genome Institute. We will test whether ancestral fungi were unicellular or hyphal based on patterns in phylogenetic trees. We will compare the well-studied genes for hyphal growth from Ascomycota with those of early-diverging fungi where they have never been analyzed. Combining the genomic sequences with the new data from additional fungal groups, we will use phylogenetic analysis of conserved genes for digesting plant materials such as cellulose or for digesting animal tissue to infer when and where the ability to breakdown plant products evolved in the fungi. This analysis has the potential to reveal new groups of enzymes with industrial applications. Combining my continuing interest in the Ascomycota and molecular clocks, we will also analyze the record of dispersed fungal spore fossils to help establish minimum ages of important diversifications. This research will contribute to training ~4 Ph.D. students to apply methods of molecular biology to questions of broad interest in fungal evolutionary biology.

真菌可以引起植物疾病，作为菌根伙伴，分解枯枝落叶和木质残体，这一切都是因为构成它们身体的管状菌丝（细胞丝，被细胞壁包围）。菌丝刺穿并渗透到基质中，同时在其复杂的细胞壁上分泌消化酶。这些酶将有机化合物消化成简单的、可扩散的分子，真菌吸收这些分子来为其生长提供燃料，使真菌成为最重要的陆地真核腐养生物。然而，系统发育证据表明真菌和动物有着共同的祖先，最早的真菌是单细胞的而不是菌丝;无壁的，可能是吞噬营养的而不是细胞壁上的营养物质;水生的，有鞭毛的阶段而不是陆生的。重建菌丝结构，分泌的消化酶和陆地生长的进化，是拟议的研究的主题。我们将利用七个新的基因组序列的早期分歧的真菌，结果我们成功的社区测序建议，美国联合基因组研究所。我们将测试是否祖先真菌是单细胞或菌丝的基础上模式的系统发育树。我们将比较子囊菌门菌丝生长的基因和早期分歧真菌的基因，这些基因从未被分析过。将基因组序列与来自其他真菌组的新数据相结合，我们将使用用于消化植物材料（如纤维素）或消化动物组织的保守基因的系统发育分析来推断何时何地分解真菌中进化的植物产物的能力。这种分析有可能揭示具有工业应用的新酶群。 结合我对子囊菌门和分子钟的持续兴趣，我们还将分析分散的真菌孢子化石的记录，以帮助建立重要多样性的最低年龄。本研究将有助于培养~4位博士。学生应用分子生物学的方法在真菌进化生物学的广泛兴趣的问题。