基于单分子实时测序的油莎豆全长转录组分析

Single-molecule real-time(SMRT)-based full-length transcriptome analysis of tigernut(Cyperus esculentus L.)

油莎豆以其适应性广、产量和含油量高而成为我国的新型油料作物。为解析油莎豆的遗传基础,服务于育种和分子生物学研究,采用单分子实时测序技术构建了油莎豆高质量的全长转录组,混合样本的组织来源包括块茎、匍匐茎、根、芽、叶片、叶鞘、花、花茎等。研究基于23.20 Gb高质量的原始数据提取获得环形一致序列319568条,其平均长度和测序深度分别为2101 bp和43×;通过聚类、校正和去冗余最终得到高质量的序列57849条,合计121.79 Mb;转录组的完整性约为79.58%,其中约有76.20%的为全长转录本;通过比对NR、Swissprot、GO、KOG、eggNOG、Pfam、KEGG等数据库,共获得52424条序列的注释信息,注释比例约为90.62%;此外,研究还预测获得3759条lncRNA、43060个SSR位点以及2300条转录因子序列。这些结果不仅增加了我们对油莎豆遗传特性的认知,同时还为下一步开展基因表达谱分析、功能基因的挖掘与利用等奠定了坚实的基础。

As a novel type of oil crop in China,tigernut(Cyperus esculentus L.)is planted for its wide adaptation,high yield and high oil content in tuber.To investigate genetic basis and to facilitate breeding and molecular biology research,a high quality full-length transcriptome was constructed based on single-molecule real-time(SMRT)sequencing.The library was derived from mixed sample of tuber,stolon,root,shoot apex,blade,sheath,flower,and floral axis.After filtering,a total of 23.20 Gb high quality data was obtained,and 319568 circular consensus sequences with an average of 2101 bp and full passes of 43 were extracted.Finally,57849 high quality transcripts,composing 121.79 Mb,were obtained after clustering,polishing and redundancy removing.The completeness of this transcriptome library was established to be 79.58%.And approximately 76.20%of the total transcripts are full-length.The BLAST search against 7 main databases including NR,Swissprot,GO,KOG,eggNOG,Pfam,and KEGG resulted in annotation of 52424 transcripts,amounting for about 90.62%of the total transcripts.Additionally,the analyses also resulted in annotation of 3759 lncRNA,43060 SSR,and 2300 transcription factor-encoding sequences.These results improved knowledges on genetic information of tigernut,and provided valuable resource for futher expression profiling and utilization of functional genes.