利用转录组测序分析与华重楼种子休眠解除相关差异基因

Analysis of differential genes related to dormancy release of Paris polyphylla var. chinensis seeds by transcriptome sequencing

为探究华重楼种子休眠解除过程中差异基因的表达情况及相关代谢通路,以华重楼休眠解除前后种胚为材料,利用新一代高通量测序手段对供试样品进行转录组测序并进行系统生物信息学分析。从cDNA文库中分别获得62 882 650,62 263 366个clean reads,共得到69 248个差异表达基因,上调的表达基因有56 426个,下调的表达基因有12 822个。共有138 267个差异表达基因被GO功能注释到生物进程、分子功能和细胞组分3个大类58个亚类,注释的差异表达基因与代谢过程、生物调控、细胞组分合成和酶催化活性等密切相关。对58 722个差异表达基因进行pathway显著性富集分析,共发现139个代谢通路,休眠前后的DEGs主要富集在碳代谢、次生代谢产物生物合成和多糖代谢等途径。基于KEGG数据库中注释结果,共发现16条与华重楼休眠解除相关的代谢通路。华重楼种子发育与休眠解除过程中大量与种胚形态建成、多糖分解及蛋白质合成的差异基因参与表达,涉及到多个代谢途径的相互作用,构成复杂的休眠解除调控网络。

The study aims at exploring the expression of differential genes and related metabolic pathways in the process of seed dormancy release. The dormant embryo and the dormant released embryo of Paris polyphylla var. chinensis were used as the test materials, a new generation high-throughput sequencing methods to sequence the transcriptome of the samples was used to carry out systematic bioinformatics analysis. We obtained 62 882 650 and 62 263 366 clean reads from the DNA libraries of the samples before and after dormancy breaking. A total of 69 248 differentially expressed genes(DEGs) were obtained, 56 426 up-regulated genes and 12 822 down-regulated genes. There are 138 267 differentially expressed genes in the process of embryo dormancy release, which were annotated by GO function to 58 subclasses of biological processes, molecular functions and cell components. The annotated differentially expressed genes were closely related to metabolic processes, biological regulation, cell component synthesis and enzyme catalytic activity. We found 139 metabolic pathways through pathway analysis of 58 722 differentially expressed genes. Before and after dormancy, DEGs were mainly enriched in carbon metabolism, secondary metabolite biosynthesis and polysaccharide metabolism. Based on the annotation results in KEGG database, we found 16 metabolic pathways related to the dormancy release of P. polyhoylla var. chinensis. A large number of differentially expressed genes were involved in embryo morphogenesis, polysaccharide decomposition and protein synthesis during seed development and dormancy release. It involves the interaction of multiple metabolic pathways and constitutes a complex regulation network for dormancy relief.