Lobes or Gills, Exploring the Origin of Insect Wings

叶或鳃，探索昆虫翅膀的起源

• 批准号: 1557936
• 负责人: Yoshinori Tomoyasu
• 金额: $ 53.18万
• 依托单位: Miami University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-05-01 至 2020-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1557936&HistoricalAwards=false
• 关键词: Lobes; Gills; Exploring; Origin; Insect

The world is full of a fascinating diversity of life. Understanding the mechanism that has driven (and continues to drive) this amazing diversity is important, not only for science, but also for life itself. Knowledge of the history of life affects our way of thinking, our culture, and our society. Only recently, scientists have finally begun to understand how new body structures (novel structures) emerge during evolution. This project uses a core example of this novelty to explore a century-long question; where did the insect wing come from? Acquisition of wings has allowed the tremendously successful expansion of insects over the globe. However, the origin of insect wings remains a mystery and is regarded as a chief conundrum in biology. Through molecular and developmental analyses, wing-related tissues will be identified from a wide set of insects and other arthropods, which will allow for a reconstruction of the evolutionary history of insect wings. Gaining a comprehensive view of insect wing evolution will in turn advance our knowledge of the developmental basis underlying the development of new structures in general. The research will also further establish several organisms as alternative models for further genetic studies. In addition, this project will enhance undergraduate science education through establishing an infrastructure for student-oriented crowdsourcing efforts allowing researchers and students to publicly share the results of their gene disruption analyses and thus facilitate collaboration opportunities.Over a century of debates and observations have culminated into two prominent hypotheses on the insect wing origin. One hypothesis, termed the paranotal hypothesis, connects the origin to the lateral extension of the dorsal thorax, the paranotal lobe. The second hypothesis, the exite hypothesis, connects the origin to the proximal leg segments and the branches (exites) stemming from these segments. Despite accumulating efforts to unveil the origin of insect wings, neither hypothesis has been able to surpass the other. A previous analysis in the Tomoyasu laboratory using Tribolium beetles has led to a combinational wing origin hypothesis, which states that insect wings have a dual origin, and that the merger of two unrelated tissues has been a key step in developing this morphologically novel structure during evolution. Further evidence for this hypothesis will be explored via (i) elucidating how the two tissues merge to form a complete wing structure in Tribolium, and (ii) identifying wing (serial) homologs from three additional species (a diving beetle, a cockroach, and a crustacean) to gain support of the hypothesis from a wider taxonomic breadth. RNA interference and expression analyses, along with CRISPR/Cas9-based genome editing techniques, will be used to identify and follow the development of wing-related tissues in these organisms. The morphological comparison of the identified wing (serial) homologs in these organisms with those of Tribolium, as well as with the proposed wing origins will allow for the construction of a more complete history of the evolution of insect wings.

世界上充满了令人着迷的生物多样性。了解驱动（并继续驱动）这种惊人多样性的机制不仅对科学很重要，对生命本身也很重要。对生命历史的了解影响着我们的思维方式、文化和社会。直到最近，科学家才终于开始了解新的身体结构（新结构）是如何在进化过程中出现的。这个项目使用这种新奇的一个核心例子来探索一个长达一个世纪的问题；昆虫的翅膀是从哪里来的？获得翅膀使得昆虫在全球范围内的扩张非常成功。然而，昆虫翅膀的起源仍然是一个谜，被认为是生物学上的一个主要难题。通过分子和发育分析，将从广泛的昆虫和其他节肢动物中识别出与翅膀相关的组织，这将允许重建昆虫翅膀的进化史。获得昆虫翅膀进化的全面观点将反过来促进我们对新结构发展背后的发展基础的了解。这项研究还将进一步建立一些生物作为进一步遗传研究的替代模型。此外，该项目将通过建立以学生为导向的众包基础设施来加强本科科学教育，使研究人员和学生能够公开分享他们的基因破坏分析结果，从而促进合作机会。一个多世纪以来的争论和观察最终形成了关于昆虫翅膀起源的两个重要假设。一种假说，被称为偏执狂假说，将起源与胸背外侧延伸，即偏执狂叶联系起来。第二种假说，即出口假说，将起源与近段腿和分支（出口）联系起来。尽管人们不断努力揭开昆虫翅膀的起源，但两种假说都无法超越对方。Tomoyasu实验室先前对Tribolium甲虫进行的分析得出了一个组合翅膀起源假说，该假说认为昆虫的翅膀有双重起源，两个不相关组织的合并是进化过程中发展这种形态新颖结构的关键一步。这一假设的进一步证据将通过(i)阐明这两个组织如何合并形成一个完整的翅膀结构，以及（ii）从另外三个物种（潜水甲虫，蟑螂和甲壳类动物）中识别翅膀（序列）同源物来从更广泛的分类宽度上支持这一假设。RNA干扰和表达分析，以及基于CRISPR/ cas9的基因组编辑技术，将用于识别和跟踪这些生物中翅膀相关组织的发育。将这些生物中已识别的翅膀（系列）同系物与Tribolium的翅膀进行形态学比较，并与提出的翅膀起源进行比较，将有助于构建更完整的昆虫翅膀进化历史。