新疆两种亚麻籽转录组分析及籽油香气差异基因挖掘

Transcriptome Analysis of Two Flaxseed Cultivars Grown in Xinjiang and Mining of Differentially Expressed Genes Related to Flaxseed Oil Aroma

为丰富亚麻籽转录组数据信息,在分子水平上探究不同品种亚麻籽所得亚麻籽油的香气差异原因,本研究选择2种新疆特色亚麻籽(伊亚-3号和天亚-6号),通过Illumina高通量测序平台对其进行转录组测序,并通过多种生物信息学方法对数据进行统计分析。结果表明:共获得61 995 756条高质量的clean reads,将测序数据进行de novo组装得到33 218个unigene;非冗余蛋白(Non-Redundant Protein,NR)数据库注释发现亚麻籽转录组与麻风树相似序列最高,有17 269个unigene在直系同源群集(Cluster of Orthologous Group,COG)数据库中注释到,分为细胞过程和信号、信息存储与处理、代谢3大类22个分支;两组样品分析显示有1 658个显著性差异表达基因(differentially expressed genes,DEGs),伊亚-3号相较于天亚-6号亚麻籽样品共有825个基因上调表达,833个基因下调表达,将DEGs在基因本体数据库中注释显示,两个品种在生物过程、细胞组分和分子功能3大类分布。注释到京都基因与基因组百科全书数据库的380个DEGs,主要富集到脂肪酸代谢等代谢途径,且脂肪酸代谢通路中可注释到17个DEGs,其中不饱和脂肪酸代谢通路中可注释到8个DEGs。本研究可为新疆不同品种亚麻籽油的香气差异分析提供理论依据和技术支撑。

This study was executed in order to enrich the transcriptome information of flaxseeds and explore the reasons for the difference in the aroma of flaxseed oils from different cultivars at the molecular level. Two specialty flaxseed cultivars(Yiya-3 and Tianya-6) in Xinjiang were selected to perform transcriptome sequencing analysis using the Illumina highthroughput sequencing platform and a variety of bioinformatic methods. The results showed that a total of 61 995 756 highquality clean reads were obtained. Further, a total of 33 218 unigenes were obtained after de novo assembling of the sequence data. Non-Redundant Protein(NR) database annotations revealed that the flaxseed transcriptome had the highest sequence similarity to Jatropha curcas, and 17 269 unigenes were annotated in the Cluster of Orthologous Group(COG) database,which were divided into 22 branches in three categories, including cellular processes and signals, information storage and processing, and metabolism. There were 1 658 significant differentially expressed genes(DEGs) identified between the two cultivars. Compared to Tianya-6, 825 genes were up-regulated and 833 genes were down-regulated in Yiya-3.The annotation of the DEGs in the Gene Ontology(GO) database showed that they were distributed in three categories:biological processes, cellular components and molecular functions. The 380 DEGs annotated in the Kyoto Encyclopedia of Genes and Genomes(KEGG) database were mainly enriched in fatty acid metabolism and other metabolic pathways, and 17 DEGs could be annotated in the fatty acid metabolism pathway, with eight being annotated in the unsaturated fatty acid metabolism pathway. This study provides a theoretical basis and technical support for the analysis of the difference in the aroma of flaxseed oils from different cultivars in Xinjiang.