Determinants of Hybrid Fitness and Genome Plasticity

这个项目将促进对杂交生物的理解，它结合了来自两个不同物种的基因组。杂交品种可以表现出新的和令人满意的性状，在某些环境中表现得比亲本物种中的任何一个都好。由于这种所谓的“杂交活力”，杂交酵母在农业中非常重要，而且杂交酵母专门执行许多工业上重要的发酵过程。更好地了解杂交将使改良作物和发酵微生物的育种和工程更有效。尽管这很重要，但杂交基因组还没有被很好地理解，所以这个项目有可能产生很大的影响。除了其科学影响外，该项目还提供了许多培训机会。由本科生研究人员组成的多元化团队将执行大部分实验，博士后研究员和研究生将接受尖端基因组学技术的培训。对公众的宣传将包括酵母生物学、发酵和基因组进化方面的教育，该项目将吸引业余爱好者和专业酿酒商参与酵母遗传学，帮助他们发现新的杂交酵母。这个项目将探索杂交基因组学中一些悬而未决的问题。它将发现杂种如何能够适应新的环境，并通过三种潜在的机制发展新的性状：消除遗传冲突，利用遗传变异，利用转座子入侵。使用自然衍生的杂交体来研究这些假设可能很困难，因为它们的生长环境历史在很大程度上是未知的。本项目将采用酵母实验进化方法来探索和理解这些问题。混血儿将在实验室中被创造出来，并在新的环境中进化。通过对“进化的”基因组进行测序，将识别出在种群中出现并达到高频率的新突变。实验将确定基因组重排、点突变和转位对杂交适应的相对贡献。然后将与从工业和自然发酵中分离出来的混合啤酒进行比较，其中一些将由酿酒师收集作为该项目的一部分。总之，该项目将有助于更好地了解杂交活力和适应性的重要分子机制。该奖项由分子和细胞生物科学部的遗传机制项目和化学、生物工程、环境和运输系统部的环境可持续性项目共同支持。

This project will advance understanding of hybrid organisms, which combine genomes from two different species. Hybrids can demonstrate new and desirable traits, performing better in some environments than either of the parent species. Because of this so-called 'hybrid vigor,' hybrids are very important in agriculture, and hybrid yeast specifically carry out many industrially important fermentation processes. Better understanding of hybrids will allow more effective breeding and engineering of improved crops and fermentation microorganisms. Despite this importance, hybrid genomes are not well understood, so this project has the potential to have high impact. In addition to its scientific impact, the project presents numerous training opportunities. A diverse team of undergraduate researchers will perform a significant portion of the experiments, and a postdoctoral fellow and graduate student will be trained in cutting edge genomics techniques. Outreach to the public will include education on yeast biology, fermentation and genome evolution, and the project will engage hobbyist and professional brewers in yeast genetics by enlisting their help to discover new hybrid yeasts.This project will explore a number of open questions in hybrid genomics. It will discover how hybrids are able to adapt to new environments and develop new traits via three potential mechanisms: eliminating genetic conflicts, leveraging genetic variation, and taking advantage of transposon invasion. Studying these hypotheses using naturally derived hybrids can be difficult because their history of growth environments is largely unknown. This project will apply a yeast experimental evolution approach to explore and understand these questions. Hybrids will be created in the lab and evolved under new environments. By sequencing the 'evolved' genomes, new mutations will be identified that have arisen in the population and achieved high frequency. Experiments will determine the relative contribution of genome rearrangements, point mutations, and transpositions to hybrid adaptation. Comparison will then be undertaken with hybrids isolated from industrial and natural fermentations, some of which will be collected by brewers as part of this project. All together, the project will lead to better understanding of the molecular mechanisms important for hybrid vigor and adaptation.This award is supported jointly by the Genetic Mechanisms program in the Division of Molecular and Cellular Biosciences and by the Environmental Sustainability program in the Division of Chemical, Bioengineering, Environmental and Transport Systems.