Mechanisms of genomic, genetic, and phenotypic divergence in the Magnaporthaceae

Magnaporthaceae 基因组、遗传和表型分化的机制

• 批准号: 93324-2010
• 负责人: Kohn, Linda
• 金额: $ 4.44万
• 依托单位: University of Toronto
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2012
• 资助国家: 加拿大
• 起止时间: 2012-01-01 至 2013-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=513570
• 关键词: Mechanisms; genomic; genetic; phenotypic; divergence

How do fungal populations adapt to infect new hosts or evolve new species? Either reconstructed statistically from genomic DNA and protein sequences, or observed in real time in the course of experimental evolution in the laboratory, we prove two key Darwinian concepts: natural selection on new variants (mutations) with those conveying adaptation (higher fitness) increasing in frequency in populations, and persistence of adaptive genotypes when hybrids between different adaptations have poorer fitness than their parents. The novel aspect is that we identify the genes in which mutations occur and the effects, in response to any stress we choose, of specific mutations, from the effect of a gene product to all ripple effects throughout the whole genome. Other speciation laboratories study existing species that evolved in events we cannot observe or reconstruct because they occurred millions of years ago. From one cell, in just 3 months, we incited speciation in 12 lab populations of baking/brewing/wine yeast. Using next-generation genome sequencing, population genomics, genetics, and transcriptomics, we have found 12 key mutations in four of the populations adapted to one of two stress environments, high salt or low glucose. Three of these mutations are in global regulators of gene expression with broad ripple effects. These same variants are found in wild vineyard yeast, not just in the lab. We propose to determine their importance in the wild in relation to how yeast uses food to produce energy. We are also using whole genomes to study an important group of plant-disease fungi, including Magnaporthe, cause of blast, the most important disease of rice worldwide, and Gaeumannomyces, cause of take all of wheat and other grains worldwide, including Canada. The objectives are to identify the genes and their variants caused by mutation that have caused diversification in these genera, specifically ability to change hosts and nutritionally exploit different grasses, including turf and cereal species. We hope to increase our ability to improve these crop species and to predict the direction of evolutionary change (in a changing world) in order to better manage disease.

真菌种群如何适应感染新宿主或进化新物种？无论是从基因组DNA和蛋白质序列的统计重建，或在实验室的实验进化过程中观察到的真实的时间，我们证明了两个关键的达尔文的概念：自然选择的新的变种（突变）与那些传达适应（更高的健身）在人口中的频率增加，和适应基因型的持久性时，不同的适应之间的杂种比他们的父母有较差的健身。新的方面是，我们确定了发生突变的基因，以及特定突变对我们选择的任何压力的反应，从基因产物的影响到整个基因组的所有涟漪反应。 其他物种形成实验室研究的是在我们无法观察或重建的事件中进化的现有物种，因为它们发生在数百万年前。 从一个细胞，在短短3个月内，我们在12个实验室群体的烘焙/酿造/葡萄酒酵母中激发了物种形成。利用下一代基因组测序、群体基因组学、遗传学和转录组学，我们在四个适应高盐或低糖两种应激环境之一的群体中发现了12个关键突变。其中三个突变位于基因表达的全球调节因子中，具有广泛的涟漪反应。这些相同的变体在野生葡萄园酵母中发现，而不仅仅是在实验室中。 我们建议确定它们在野外的重要性，与酵母如何利用食物产生能量有关。 我们还利用全基因组研究一组重要的植物病害真菌，包括稻瘟病菌（Magnaporthe），这是全世界最重要的水稻病害，以及全世界包括加拿大在内的所有小麦和其他谷物的病原体。 其目的是确定基因及其变异引起的突变，导致这些属的多样化，特别是改变主机和营养利用不同的草，包括草坪和谷物物种的能力。 我们希望提高我们改进这些作物品种的能力，并预测进化变化的方向（在不断变化的世界中），以便更好地管理疾病。