Sperm, speciation and gene drives in evolution

进化中的精子、物种形成和基因驱动

• 批准号: RGPIN-2018-05098
• 负责人: Cutter, Asher
• 金额: $ 5.68万
• 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: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=648452
• 关键词: Sperm; speciation; gene; drives; evolution

Two of the fundamental features of the living world are seemingly invisible in everyday experience: evolutionary change and the DNA of our genomes. But in the lab, rapidly developing animals like the ‘elegant roundworm' C. elegans let us observe real evolution across scores of generations in just weeks. Moreover, the genomic biotechnology revolution of the past decade lets us access root causes of differences between individuals and species, so we can capture a complete genetic snapshot of evolution. What happens when we combine experimental evolution with genome sequencing is biological cinematography: by collecting genomic information over time, we record a genomic ‘movie'. This research aims to record and analyze movies of evolutionary genomic change for C. elegans to test and understand 1) dynamics of new ‘CRISPR/Cas9 gene drive' biotechnology for genetic engineering biocontrol and 2) genomic causes of incompatibility between species that keeps gene pools separate. In parallel, 3) we conduct experiments to understand rapid evolution of a special cell type, sperm cells, that we discovered to cause reproductive barriers between species. By integrating whole-genome analysis with evolution experiments and mechanistic studies, this research makes tangible the abstract foundations of the living world to help explain the origins and maintenance of biodiversity.******1. Gene Drive Evolution: New CRISPR/Cas9 gene drive biotech provides an innovative means to fight pest species by engineering their populations for biocontrol, to thwart environmental degradation and improve public health. But release of gene drives into nature presents serious ethical, practical, and environmental concerns. This research will test predictions about gene drive spread across dozens of generations in realistic lab circumstances using C. elegans as an ideal and low-risk model. This real-time study of evolution is crucial to developing evidence-based policy and procedures.***2. Speciation Genomics: What genomic changes keep one group of individuals separate from another to create and maintain biodiversity? We use an experimental evolutionary genomics approach, hybridizing two closely-related nematode roundworm species. We then use evolutionary genomic ‘movie-making' to home in on genes that diverged and test how they disrupt genetic networks and developmental programs in hybrids to cause gonad and embryonic defects, yet facilitate proper function within pure species.***3. Sperm Evolution: We discovered a fascinating new way that genetic systems can evolve mismatches: sperm cell migration into the body cavity that causes female sterility and death. We are using this convenient cellular microcosm to explore evolutionary cell biology using high-powered microscopy and genetic editing to understand the general evolutionary processes that shape the morphology and behavior of such fundamental cells as gametes.

生命世界的两个基本特征在日常生活中似乎是看不见的：进化变化和我们基因组的DNA。但在实验室里，像“优雅的蛔虫”秀丽隐杆线虫这样快速发育的动物让我们在短短几周内就能观察到几十代人的真正进化。此外，过去十年的基因组生物技术革命让我们了解了个体和物种之间差异的根本原因，因此我们可以捕捉到进化的完整基因快照。当我们将实验进化与基因组测序结合起来时，会发生的事情就是生物摄影：通过收集基因组信息，我们记录了一部基因组“电影”。本研究旨在记录和分析秀丽隐杆线虫的进化基因组变化，以测试和了解1)用于基因工程生物防治的新型“CRISPR/Cas9基因驱动”生物技术的动力学和2)物种之间不相容的基因组原因，使基因库分离。与此同时，我们进行实验来了解一种特殊细胞类型——精子细胞的快速进化，我们发现它会导致物种之间的繁殖障碍。通过将全基因组分析与进化实验和机制研究相结合，本研究使生命世界的抽象基础具体化，以帮助解释生物多样性的起源和维持。******1。基因驱动进化：新的CRISPR/Cas9基因驱动生物技术提供了一种创新的手段，通过改造害虫种群进行生物防治，阻止环境退化，改善公众健康。但是，将基因驱动释放到自然中会引起严重的伦理、实践和环境问题。这项研究将以秀丽隐杆线虫作为理想的低风险模型，在现实的实验室环境中测试关于基因驱动在几十代之间传播的预测。这种实时进化研究对于制定基于证据的政策和程序至关重要。***2。物种形成基因组学：什么样的基因组变化使一组个体与另一组个体区分开来，从而创造和维持生物多样性？我们使用实验进化基因组学方法，杂交两个密切相关的线虫蛔虫物种。然后，我们使用进化基因组“电影制作”来定位分化的基因，并测试它们如何破坏杂交基因网络和发育程序，从而导致性腺和胚胎缺陷，同时促进纯物种的正常功能。精子进化：我们发现了一种令人着迷的新方式，遗传系统可以进化出不匹配：精子细胞迁移到体腔，导致女性不育和死亡。我们正在使用这种方便的细胞微观世界来探索进化细胞生物学，使用高倍显微镜和基因编辑来了解塑造配子等基本细胞形态和行为的一般进化过程。