雌、雄弓背青鳉(Oryzias curvinotus)肝脏转录组比较分析

COMPARATIVE TRANSCRIPTOME ANALYSIS OF MALE AND FEMALE LIVER OF ORYZIAS CURVINOTUS

为发掘弓背青鳉(Oryzias curvinotus)肝脏功能基因、开发环境检测标记基因,本研究采用RNA-Seq技术分别测定了性成熟雌、雄弓背青鳉肝脏转录组,并获得80095044和87043984条clean reads,合并拼接出49912个unigenes(N50=2394bp)。基因表达差异分析显示在雌、雄弓背青鳉肝脏组织中存在571个差异基因(DEGs),其中364个在雄鱼中高表达,207个在雌鱼中高表达。GO和KEGG分析表明差异基因主要参与激素合成、免疫反应、氧化还原反应及卵黄发生等生物学过程。进一步,在转录组中筛选到了多个环境雌激素相关标记基因(vtgs,chgs,er,cyp450等),且这些基因在雌鱼肝脏中的表达水平显著高于雄鱼。研究结果丰富了弓背青鳉的基因资源,为研究基因功能提供了数据,也有助于进一步研究鱼类肝脏在不同性别之间的功能。

Oryzias curvinotus is distributed mainly along the coast of the South China Sea.To date,there are no genomic or transcriptomic studies on O.curvinotus.We constructed hepatic transcriptomes of male and female O.curvinotus using Illumina sequencing and identified genes that may be involved in protein synthesis,cell metabolism,and immunity.In total,80095044 and 87043984 clean reads were obtained from the female and male liver,respectively.Reads were assembled into 49912 unigenes in N50 value of 2394bp.Gene expression patterns in the male and female livers were compared,and 571 differentially expressed genes(DEGs)were identified.Of these genes,364 were up-regulated in the male and 207 in the female.RT-qPCR analysis of 12 selected genes showed patterns consistent with the transcriptome results.GO and KEGG analysis showed that the differential genes were mainly involved in the biological processes of hormone synthesis,immune response,redox reaction,and vitellogenesis etc.Furthermore,multiple environmental estrogen-marker genes(vtgs,chgs,er,cyp450,etc.)were screened in the transcriptome of the liver of medaka,and the expression level in the female liver was significantly higher than that in the male’s.The results enrich the genetic resources of the O.curvinotus,provide data for the study of gene function,and contribute to the further study of the function of fish livers between different genders.