电鲶基因组解析与强电鱼释放高压电的分子机制研究

Most of the extant fishes use bite as the manner of prey and defense, but strongly electric fishes could finish these processes through instantaneously discharge high-voltage electricity. However, the molecular and genetic basics of strongly electric fishes discharge high-voltage electricity and their adaptation evolution are still unclear. In this project, we will analyze the electric catfish (Malapterurus electricus) genome as the penetration point, use comparative genomics strategies systematically study the evolvement process of strongly electric fishes form electric organ and discharge high-voltage electricity. Meanwhile, we will study the dynamic process of population history, the relative evolution rate of species, and the genetic basics behind the phenotype changes (the disappearance of scales, the degeneration of teeth and vision) in strongly electric fishes. Our project will not only helps the understanding of the novelty and evolvement in complex traits of animals, but also provides new ideals in the development of bio-electricity tools and equipments by the inspiration from the strongly electric fishes.

现存的绝大多数鱼类都是利用撕咬的方式进行捕食和防御，而强电鱼（strongly electric fish）却能够通过瞬间释放超过上百伏的高压电来完成这一过程。然而，到目前为止我们对于强电鱼类释放超强高压电的分子机理以及其适应性进化的遗传基础仍然知之甚少。本项目将以解析强电鱼电鲶（Malapterurus electricus）的基因组为切入点，利用比较基因组学的手段系统性地探究强电鱼在漫长的进化过程中演化出电器官并释放高压电的分子基础。同时，我们将探究强电鱼群体的历史动态变化过程、物种相对进化速率以及长期适应过程中所发生的表型变化（鳞片的消失、牙齿和视力的退化）背后的遗传基础。本项目的开展不仅为我们进一步了解动物复杂性状的创新和演化提供帮助，而且为我们未来以强电鱼类为灵感的生物电工具和装备的开发提供新思路。

强电鱼演化出了独特的电器官用于捕食和防御。然而，到目前为止我们对强电鱼的系统发育关系和放电的潜在遗传基础知之甚少。在本项目中，我们对三个已知的强电鱼类进行了染色体水平的基因组组装。比较基因组学分析表明了三种强电鱼与其他鱼类的系统发育关系及它们电器官的独立起源。此外，我们发现个别离子通道相关的基因在某些电鱼基因组中发生了氨基酸突变。三种电鱼多个不同组织器官的转录组比较分析发现，电器官可能由骨骼肌演化而来及一些基因在三种电鱼间发生了相似的基因表达谱变化。到目前为止，我们已经发表了1篇与本项目有关的科研论文，还有1篇文章正在投稿阶段。该研究不仅为我们理解电鱼的演化及释放强电的潜在遗传基础提供帮助，更为领域内进行系统性的电鱼研究提供重要的基因组资源。