Whole-exome sequencing and genome-wide evolutionary analyses identify novel candidate genes associated with infrared perception in pit vipers
Whole-exome sequencing and genome-wide evolutionary analyses identify novel candidate genes associated with infrared perception in pit vipers
复制标题
全外显子组测序和全基因组进化分析确定了与坑毒蛇红外感知相关的新候选基因
DOI：
10.1038/s41598-020-69843-w
复制
发表时间：
2020
影响因子：
4.6
通讯作者：
Zhang Peng
中科院分区：
文献类型：
--
作者：
Tu Na;Liang Dan;Zhang Peng
蝮蛇拥有独特的热感觉系统，由面部凹陷组成，使它们能够探测到环境中微小的温度波动。生物学家长期以来一直试图阐明坑蛇红外感知的遗传基础。早期的研究表明，trpa1基因是与坑蛇红外探测相关的热传感器。然而，trpa1以外的基因是否也参与了坑蛇的红外感知仍然未知。在这里，我们对10种蛇的整个外显子组进行了测序，并进行了全基因组进化分析，以寻找可能参与坑蛇红外感知的新的候选基因。我们采用分支长度比较和选择压力改变分析来确定在毒蛇祖先谱系中特异性经历加速进化的基因。共鉴定出47个基因。这些基因在离子跨膜转运、膜电位稳定和温度门控活性功能类别中显著富集。本研究还研究了这些候选基因在相关神经组织（三叉神经节、背根神经节、中脑和大脑）中的表达水平。我们进一步选择了其中一个候选基因，钾通道基因kcnk4，作为例子来讨论它在坑蛇红外感知中的可能作用。我们的研究首次通过比较进化分析对坑蛇红外感知相关基因进行了全基因组调查，并为未来的功能研究揭示了有价值的候选基因。
Pit vipers possess a unique thermal sensory system consisting of facial pits that allow them to detect minute temperature fluctuations within their environments. Biologists have long attempted to elucidate the genetic basis underlying the infrared perception of pit vipers. Early studies have shown that theTRPA1gene is the thermal sensor associated with infrared detection in pit vipers. However, whether genes other thanTRPA1are also involved in the infrared perception of pit vipers remains unknown. Here, we sequenced the whole exomes of ten snake species and performed genome-wide evolutionary analyses to search for novel candidate genes that might be involved in the infrared perception of pit vipers. We applied both branch-length-comparison and selection-pressure-alteration analyses to identify genes that specifically underwent accelerated evolution in the ancestral lineage of pit vipers. A total of 47 genes were identified. These genes were significantly enriched in the ion transmembrane transporter, stabilization of membrane potential, and temperature gating activity functional categories. The expression levels of these candidate genes in relevant nerve tissues (trigeminal ganglion, dorsal root ganglion, midbrain, and cerebrum) were also investigated in this study. We further chose one of our candidate genes, the potassium channel geneKCNK4, as an example to discuss its possible role in the infrared perception of pit vipers. Our study provides the first genome-wide survey of infrared perception-related genes in pit vipers via comparative evolutionary analyses and reveals valuable candidate genes for future functional studies.