核糖体小亚基V4和V9区引物扩增大亚湾真核浮游生物的比较研究

Comparison of eukaryotic plankton compositions using 18S rRNA gene V4and V9 primers amplification in Daya Bay

对大亚湾水体的环境DNA分别进行18S rDNA的V4和V9区的引物扩增,通过高通量测序技术进行测序,并比较分析二者浮游真核生物基因多样性和相对丰度。18S rDNA V4区引物扩增共检测出浮游动物56纲,101目,浮游植物52纲,69目;18S rDNA V9区引物扩增共检测出浮游动物47纲,81目,浮游植物56纲,101目。两对引物对浮游真核生物扩增都具有较高覆盖度,在纲级别上二者的结果相近:颚足纲(Maxillopoda)是浮游动物优势类群;甲藻纲(Dinophyceae)、圆筛藻纲(Coscinodiscophyceae)、小豆藻纲(Mamiellophyceae)是浮游植物优势类群,其中甲藻纲多样性与丰度的结果相近,而18S rDNA V9区引物扩增得到的圆筛藻纲丰度高于18S rDNA V4区引物。分析结果表明,18S rDNAV4区引物扩增的浮游动物多样性比18SrDNAV9区引物高,而18SrDNAV9区引物扩增的浮游植物多样性比18S rDNA V4区引物高。同时,通过高通量测序技术首次确定大亚湾海区大量存在着寄生型甲藻(Syndiniales),小豆藻目(Mamiellales)。

We compared the genetic diversity and relative abundance of eukaryotic plankton in Daya Bay using two genetic markers(18S rRNA V4 and V9 regions) to amplify the eDNA and high-throughput sequencing technology. 56 classes, 101 orders of zooplankton and 52 classes, 69 orders of phytoplankton were detected using 18S rDNA V4 markers. And 47 classes, 81 orders of zooplankton and 56 classes, 101 orders of phytoplankton were detected using 18S rDNA V9 markers. Both 18S rDNA V4 and V9regions results performed well to coverage communities and provided similar eukaryotic plankton distribution patterns at class taxonomic level. Maxillopoda is the dominant group of zooplankton, while Dinophyceae, Coscinodiscophyceae and Mamiellophyceae are the dominant groups of phytoplankton. Especially, two genetic markers amplification results present the similar diversity and relative abundance of Dinophyceae at order taxonomic level. The results of 18S rDNA V9 region presented higher abundance of Coscinodiscophyceae than that of V4. The results showed that the diversity of zooplankton amplification by 18S rDNA V4 primers was higher than that of 18S rDNA V9 primers, while that of phytoplankton amplification by 18S rDNA V9primers was higher than that of 18S rDNA V4 primers. In this study, we first report high abundance parasitic Syndiniales and Mamiellales in Daya Bay.