Background Schistosoma japonicum is a parasitic flatworm that causes human schistosomiasis, which is a significant cause of morbidity in China, the Philippines and Indonesia.Oncomelania hupensis (Gastropoda: Pomatiops...Background Schistosoma japonicum is a parasitic flatworm that causes human schistosomiasis, which is a significant cause of morbidity in China, the Philippines and Indonesia.Oncomelania hupensis (Gastropoda: Pomatiopsidae) is the unique intermediate host ofS. japonicum. A complete genome sequence ofO. hupensis will enable the fundamental understanding of snail biology as well as its co-evolution with theS. japonicum parasite. Assembling a high-quality reference genome ofO. hupehensis will provide data for further research on the snail biology and controlling the spread ofS. japonicum.Methods The draft genome was de novo assembly using the long-read sequencing technology (PacBio Sequel II) and corrected with Illumina sequencing data. Then, using Hi-C sequencing data, the genome was assembled at the chromosomal level. CAFE was used to do analysis of contraction and expansion of the gene family and CodeML module in PAML was used for positive selection analysis in protein coding sequences.Results A total length of 1.46 Gb high-qualityO. hupensis genome with 17 unique full-length chromosomes (2n = 34) of the individual including a contig N50 of 1.35 Mb and a scaffold N50 of 75.08 Mb. Additionally, 95.03% of these contig sequences were anchored in 17 chromosomes. After scanning the assembled genome, a total of 30,604 protein-coding genes were predicted. Among them, 86.67% were functionally annotated. Further phylogenetic analysis revealed thatO. hupensis was separated from a common ancestor ofPomacea canaliculata andBellamya purificata approximately 170 million years ago. Comparing the genome ofO. hupensis with its most recent common ancestor, it showed 266 significantly expanded and 58 significantly contracted gene families (P < 0.05). Functional enrichment of the expanded gene families indicated that they were mainly involved with intracellular, DNA-mediated transposition, DNA integration and transposase activity.Conclusions Integrated use of multiple sequencing technologies, we have successfully constructed the genome at the chromosomal-level ofO. hupensis. These data will not only provide the compressive genomic information, but also benefit future work on population genetics of this snail as well as evolutional studies betweenS. japonicum and the snail host.展开更多
目的建立一种快速检测日本血吸虫感染性钉螺的方法。方法采用环介导等温扩增技术(LAMP)以日本血吸虫的特异基因为靶序列,利用Primer Explorer V3软件设计扩增靶基因的4条LAMP引物,酚氯仿法提取感染性钉螺中的日本血吸虫DNA,取适量模板DN...目的建立一种快速检测日本血吸虫感染性钉螺的方法。方法采用环介导等温扩增技术(LAMP)以日本血吸虫的特异基因为靶序列,利用Primer Explorer V3软件设计扩增靶基因的4条LAMP引物,酚氯仿法提取感染性钉螺中的日本血吸虫DNA,取适量模板DNA加入LAMP反应体系进行对日本血吸虫靶基因扩增,经肉眼观察、SYBR Green I染色电泳及测DNA序列来判定扩增产物。在99个阴性钉螺中各加入1个阳性钉螺,其中每个阳性钉螺分别感染日本血吸虫毛蚴数量分别为10、8、6、4、2、1条。结果感染性钉螺检测管经显色呈绿色为阳性,阴性钉螺呈棕色;日本血吸虫的特异基因经LAMP扩增后电泳呈现LAMP特征性梯状条带,阴性钉螺及感染肝吸虫不出现LAMP特征性梯状条带;扩增产物经酶切及序列分析显示为目的基因;在100个钉螺中只要有2条日本血吸虫毛蚴感染便可检出。结论环介导等温扩增技术(LAMP)可快速有效检测日本血吸虫感染性钉螺,有望为疫区日本血吸虫感染性钉螺高效快速检测提供一种新方法 。展开更多
基金supported by National Key Research and Development Program of China(No.2021YFC2300800,2021YFC2300803).
文摘Background Schistosoma japonicum is a parasitic flatworm that causes human schistosomiasis, which is a significant cause of morbidity in China, the Philippines and Indonesia.Oncomelania hupensis (Gastropoda: Pomatiopsidae) is the unique intermediate host ofS. japonicum. A complete genome sequence ofO. hupensis will enable the fundamental understanding of snail biology as well as its co-evolution with theS. japonicum parasite. Assembling a high-quality reference genome ofO. hupehensis will provide data for further research on the snail biology and controlling the spread ofS. japonicum.Methods The draft genome was de novo assembly using the long-read sequencing technology (PacBio Sequel II) and corrected with Illumina sequencing data. Then, using Hi-C sequencing data, the genome was assembled at the chromosomal level. CAFE was used to do analysis of contraction and expansion of the gene family and CodeML module in PAML was used for positive selection analysis in protein coding sequences.Results A total length of 1.46 Gb high-qualityO. hupensis genome with 17 unique full-length chromosomes (2n = 34) of the individual including a contig N50 of 1.35 Mb and a scaffold N50 of 75.08 Mb. Additionally, 95.03% of these contig sequences were anchored in 17 chromosomes. After scanning the assembled genome, a total of 30,604 protein-coding genes were predicted. Among them, 86.67% were functionally annotated. Further phylogenetic analysis revealed thatO. hupensis was separated from a common ancestor ofPomacea canaliculata andBellamya purificata approximately 170 million years ago. Comparing the genome ofO. hupensis with its most recent common ancestor, it showed 266 significantly expanded and 58 significantly contracted gene families (P < 0.05). Functional enrichment of the expanded gene families indicated that they were mainly involved with intracellular, DNA-mediated transposition, DNA integration and transposase activity.Conclusions Integrated use of multiple sequencing technologies, we have successfully constructed the genome at the chromosomal-level ofO. hupensis. These data will not only provide the compressive genomic information, but also benefit future work on population genetics of this snail as well as evolutional studies betweenS. japonicum and the snail host.
文摘目的建立一种快速检测日本血吸虫感染性钉螺的方法。方法采用环介导等温扩增技术(LAMP)以日本血吸虫的特异基因为靶序列,利用Primer Explorer V3软件设计扩增靶基因的4条LAMP引物,酚氯仿法提取感染性钉螺中的日本血吸虫DNA,取适量模板DNA加入LAMP反应体系进行对日本血吸虫靶基因扩增,经肉眼观察、SYBR Green I染色电泳及测DNA序列来判定扩增产物。在99个阴性钉螺中各加入1个阳性钉螺,其中每个阳性钉螺分别感染日本血吸虫毛蚴数量分别为10、8、6、4、2、1条。结果感染性钉螺检测管经显色呈绿色为阳性,阴性钉螺呈棕色;日本血吸虫的特异基因经LAMP扩增后电泳呈现LAMP特征性梯状条带,阴性钉螺及感染肝吸虫不出现LAMP特征性梯状条带;扩增产物经酶切及序列分析显示为目的基因;在100个钉螺中只要有2条日本血吸虫毛蚴感染便可检出。结论环介导等温扩增技术(LAMP)可快速有效检测日本血吸虫感染性钉螺,有望为疫区日本血吸虫感染性钉螺高效快速检测提供一种新方法 。
