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不可见的：进化变化和我们基因组的DNA。但在实验室里，像“优雅蛔虫”C。秀丽线虫让我们在短短几周内观察到几十代人之间真实的进化。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。当我们将联合收割机实验进化与基因组测序结合起来时，所发生的事情就是生物电影摄影：通过随时间收集基因组信息，我们记录了一部基因组“电影”。本研究旨在记录和分析C. elegans来测试和理解1）用于基因工程生物控制的新的“CRISPR/Cas9基因驱动”生物技术的动态，以及2）保持基因库分离的物种之间不相容的基因组原因。与此同时，3）我们进行实验，以了解一种特殊的细胞类型，精子细胞的快速进化，我们发现它会导致物种之间的生殖障碍。通过将全基因组分析与进化实验和机制研究相结合，这项研究使生物世界的抽象基础变得有形，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，通过设计其种群进行生物控制来对抗害虫物种，以阻止环境退化并改善公共健康。但是，将基因驱动器释放到自然界会带来严重的伦理、实践和环境问题。这项研究将使用C. elegans作为一个理想的低风险模型。这种对进化的实时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分开，以创造和维持生物多样性？我们使用实验进化基因组学的方法，杂交两个密切相关的线虫蛔虫物种。然后，我们使用进化的基因组“电影制作”来定位那些分化的基因，并测试它们如何破坏杂交后代的遗传网络和发育程序，从而导致性腺和胚胎缺陷，但又有助于纯物种的正常功能。3.精子进化：我们发现了一种令人着迷的新方式，即遗传系统可以进化出不匹配：精子细胞迁移到体腔中，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的形态和行为的一般进化过程。