Evolutionary Basis of High-Frequency Hearing in the Cochleae of Echolocators Revealed by Comparative Genomics
Evolutionary Basis of High-Frequency Hearing in the Cochleae of Echolocators Revealed by Comparative Genomics
复制标题
比较基因组学揭示回声定位器耳蜗高频听力的进化基础
DOI：
10.1093/gbe/evz250
复制
发表时间：
2020-01-01
影响因子：
3.3
通讯作者：
Feng，Jiang
中科院分区：
文献类型：
--
作者：
Wang，Hui;Zhao，Hanbo;Feng，Jiang
高频听觉对于回声定位蝙蝠和鲸鱼的生存都很重要，但我们对其遗传基础的理解是分散和分段的。在这项研究中，我们将RNA-Seq和比较基因组分析相结合，以深入了解耳蜗的综合基因表达谱和听力相关基因的适应性进化。在不同种类的回声定位蝙蝠和齿鲸中，共有144个基因被发现处于正选择状态，其中34个被确定与听觉行为或听觉过程有关。随后，发现与这些基因相关的多种生理过程在回声定位蝙蝠和齿鲸中适应性进化，包括耳蜗骨骼发育，抗氧化活性，离子平衡和稳态过程沿着信号转导。此外，丰富的收敛/平行的基因和网站之间检测到不同对回声定位器的物种，但是，没有特定的听觉相关的生理途径，他们丰富和几乎所有的收敛/平行信号是选择性中性的，如前所述。值得注意的是，TECPR 2中的两个适应性平行进化位点被证明是正选择的，表明它们在喉回声定位蝙蝠回声定位和高频听觉进化中的功能重要性。这项研究加深了我们对回声定位蝙蝠和齿鲸耳蜗高频听觉的遗传基础的理解。
Abstract High-frequency hearing is important for the survival of both echolocating bats and whales, but our understanding of its genetic basis is scattered and segmented. In this study, we combined RNA-Seq and comparative genomic analyses to obtain insights into the comprehensive gene expression profile of the cochlea and the adaptive evolution of hearing-related genes. A total of 144 genes were found to have been under positive selection in various species of echolocating bats and toothed whales, 34 of which were identified to be related to hearing behavior or auditory processes. Subsequently, multiple physiological processes associated with those genes were found to have adaptively evolved in echolocating bats and toothed whales, including cochlear bony development, antioxidant activity, ion balance, and homeostatic processes, along with signal transduction. In addition, abundant convergent/parallel genes and sites were detected between different pairs of echolocator species; however, no specific hearing-related physiological pathways were enriched by them and almost all of the convergent/parallel signals were selectively neutral, as previously reported. Notably, two adaptive parallel evolved sites in TECPR2 were shown to have been under positive selection, indicating their functional importance for the evolution of echolocation and high-frequency hearing in laryngeal echolocating bats. This study deepens our understanding of the genetic bases underlying high-frequency hearing in the cochlea of echolocating bats and toothed whales.