Institute of Evolution and Ecology, International Research Centre of Ecology and Environment, College of Life Sciences, Central China Normal University, Wuhan, 430079, China.
College of Life Science, Zhengzhou Normal University, Zhengzhou, 450044, China.
BMC Genomics. 2019 Jul 8;20(1):562. doi: 10.1186/s12864-019-5931-7.
The production of foam nests is one of the strategies that has evolved to allow some anuran species to protect their eggs and larvae. Despite considerable knowledge of the biochemical components of and construction behavior leading to anuran foam nests, little is known about the molecular basis of foam nest construction. Rhacophorus omeimontis presents an arboreal foam-nesting strategy during the breeding season. To better understand the molecular mechanism of foam nest production, transcriptome sequencing was performed using the oviduct of female R. omeimontis during the period when foam nest production began and the period when foam nest production was finished.
The transcriptomes of six oviduct samples of R. omeimontis were obtained using Illumina sequencing. A total of 84,917 unigenes were obtained, and 433 genes (270 upregulated and 163 downregulated) were differentially expressed between the two periods. These differentially expressed genes (DEGs) were mainly enriched in extracellular space and extracellular region based on Gene Ontology (GO) enrichment analysis and in the pathways of two-component system, cell adhesion molecules, steroid hormone biosynthesis and neuroactive ligand-receptor interaction based on Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. Specifically, genes encoding lectins, surfactant proteins and immunity components were highly expressed when the foam nest construction began, indicating that the constituents of foam nests in R. omeimontis were likely a mixture of surfactant, lectins and immune defense proteins. During the period when foam nest production was finished, genes related to lipid metabolism, steroid hormone and immune defense were highly expressed, indicating their important roles in regulating the process of foam nesting.
Our study provides a rich list of potential genes involved in the production of foam nests in R. omeimontis. These results provide insights into the molecular mechanisms underlying the process of foam nest construction and will facilitate further studies of R. omeimontis.
泡沫巢的产生是某些蛙类物种保护其卵和幼虫的策略之一。尽管人们对蛙类泡沫巢的生化成分和构建行为有了相当多的了解，但对泡沫巢构建的分子基础知之甚少。疣螈呈现出繁殖季节的树栖泡沫筑巢策略。为了更好地理解泡沫巢产生的分子机制，我们对处于泡沫巢产生开始和结束两个时期的雌性疣螈输卵管进行了转录组测序。
使用 Illumina 测序获得了六个疣螈输卵管样本的转录组。共获得了 84917 个 unigenes，其中有 433 个基因（270 个上调，163 个下调）在两个时期之间存在差异表达。这些差异表达基因（DEGs）主要富集在基因本体论（GO）富集分析中的细胞外空间和细胞外区域以及京都基因与基因组百科全书（KEGG）富集分析中的双组分系统、细胞黏附分子、甾体激素生物合成和神经活性配体-受体相互作用途径。具体而言，当泡沫巢构建开始时，编码凝集素、表面活性剂蛋白和免疫成分的基因高度表达，表明疣螈泡沫巢的成分可能是表面活性剂、凝集素和免疫防御蛋白的混合物。在泡沫巢产生结束时，与脂质代谢、甾体激素和免疫防御相关的基因高度表达，表明它们在调节泡沫筑巢过程中起着重要作用。
我们的研究为疣螈泡沫巢产生过程中涉及的潜在基因提供了丰富的列表。这些结果为泡沫巢构建过程的分子机制提供了深入的了解，并将促进对疣螈的进一步研究。
