Evolutionary Ecology of Genetic Systems

遗传系统的进化生态学

• 批准号: RGPIN-2020-05652
• 负责人: Husband, Brian
• 金额: $ 4.74万
• 依托单位: University of Guelph
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=717787
• 关键词: Evolutionary; Ecology; Genetic; Systems

My research program explores the ecology and genetics of plant populations, both wild and domesticated. These attributes of living things are fundamental to understanding changes in abundance and genetic diversity in organisms, and necessary for building sustainable food sources, managing impacts of invasive species, and conserving species at risk. My research team pursues this goal by focusing on reproductive systems, which control the quantity and quality of sperm and eggs, patterns of mating, and ultimately the transmission of genetic variation from one generation to the next. In this proposal, I focus on one aspect of reproduction, whole genome duplication, a process by which organisms produce offspring with double the chromosome number, which leads to new species (called polyploids) with as many as 86 copies of every chromosome in each cell. This phenomenon is widespread in wild plants and animals (even humans!). It is also a feature of some cancer tissues and is used as a genetic tool for breeding bigger and better crops (watermelon, strawberries, potatoes, poplar) and ornamental plants. Unfortunately, our understanding of the causes and impacts of whole genome duplication are limited, which prevents us from fully understanding factors regulating biological diversity and managing the effects of polyploidy on health and food security. To address this knowledge gap, we propose to study the mechanisms by which new polyploids form and establish, explore why polyploids arise in some organisms and not others, and predict the effects of whole genome duplication on the function of organisms and their interaction with other species. Our research will initially focus on production of unreduced gametes, whereby errors in gamete formation give rise to sperm and eggs with twice the normal number of chromosomes. Using several species, we will investigate unreduced gamete production along environmental gradients (elevation) and in growth chambers to determine the role that environmental change and stress can play in causing these errors, which give rise to polyploid offspring. We will also study the impacts of whole genome duplication by identifying independent polyploid origins in wild species and synthesizing new polyploids from a variety of genetic backgrounds in the lab, and then evaluating their performance at morphological, physiological and genetic levels. Using apples, we will then examine the potential interactions between related domestic and wild species that differ in their ploidy levels. In this species, the potential for hybridization and gene escape from domestic apple into native apples is an example of the risks associated with these interactions. Through this research, I expect to advance the methods by which we study whole genome duplication using flow cytometry and genetic markers and improve our ability to both understand the importance of this process to biological diversity and manage it for the benefit of society.

我的研究项目探索野生和驯化植物种群的生态学和遗传学。生物的这些属性是了解生物丰度和遗传多样性变化的基础，对于建立可持续的食物来源、管理入侵物种的影响和保护濒危物种是必要的。我的研究团队通过专注于生殖系统来追求这一目标，生殖系统控制着精子和卵子的数量和质量，交配模式，并最终控制遗传变异从一代传到下一代。 在这项提议中，我将重点放在生殖的一个方面--全基因组复制，即有机体产生的后代的染色体数量增加一倍，从而产生新物种(称为多倍体)，每个细胞中的每条染色体都有多达86个拷贝。这种现象在野生动植物(甚至人类！)中普遍存在。它也是一些癌症组织的特征，被用作培育更大更好的作物(西瓜、草莓、土豆、杨树)和观赏植物的遗传工具。不幸的是，我们对全基因组复制的原因和影响的了解有限，这阻碍了我们充分了解调节生物多样性的因素和管理多倍体对健康和粮食安全的影响。 为了解决这一认识差距，我们建议研究新的多倍体形成和建立的机制，探索为什么多倍体在一些生物体中出现而不是在另一些生物体中出现，并预测全基因组复制对生物体功能的影响以及它们与其他物种的相互作用。我们的研究最初将集中在未减少配子的产生上，配子形成中的错误会导致精子和卵子的染色体数量是正常的两倍。利用几个物种，我们将研究环境梯度(海拔)和生长室中未减少的配子产生，以确定环境变化和压力在导致这些错误中所起的作用，这些错误会导致多倍体后代。我们还将在实验室中通过鉴定野生物种中独立的多倍体起源和从各种遗传背景合成新的多倍体，然后在形态、生理和遗传水平上评估它们的表现，来研究全基因组复制的影响。然后，我们将使用苹果来研究不同倍性水平的相关家养物种和野生物种之间的潜在相互作用。在该物种中，从本地苹果到本地苹果的杂交和基因逃逸的可能性是与这些相互作用相关的风险的一个例子。 通过这项研究，我希望推动我们利用流式细胞术和遗传标记研究全基因组复制的方法，并提高我们理解这一过程对生物多样性的重要性并为社会造福的能力。