不同种植密度下两个不同耐密植性甘蓝型油菜的转录组比较分析

Transcriptome Comparative Analysis of Two Brassica napus Varieties With Differences in Dense Plant Tolerance Under Different Planting Densities

合理密植是提高甘蓝型油菜(Brassica napus)产量的重要途径。为探讨油菜对密植的分子响应,本研究以耐密植和不耐密植甘蓝型油菜品种为研究对象,在常规密度和高密度种植条件下对其上位叶和下位叶进行转录组测序。经比较分析,在两品种的上位叶和下位叶样品分别筛选出共有差异表达基因94个和407个,这些基因在两个品种中的表达都随着种植密度不同而表现出差异。通过加权共表达基因网络分析(weighted gene coexpression network analysis,WGCNA)筛选出与耐密植油菜显著正相关的blue和purple模块,对其进行GO富集分析,并从核心基因中筛选出12个核心转录因子(包括EIN3/EIL1、HD-ZIP、bHLH、TCP、NAC和ERF)和1个蓝光受体基因CRY2。功能注释显示多个核心基因对应的拟南芥(Arabidopsis thaliana)同源基因参与避荫反应。本研究可为甘蓝型油菜耐密植性改良提供数据参考和候选基因资源。

For rapeseed(Brassica napus),the ideal plant density is important for yield improvement.To explore density responses of rapeseed,this study focused on a transcriptome analysis of upper and lower leaves of density-tolerance rapeseed varieties and non density-tolerance rapeseed varieties under normal and high plant densities.After comparative analysis,94 differentially expressed genes in the upper leaves and 407 differentially expressed genes in the lower leaves of both varieties were selected.The expression of these genes in both varieties showed differences under different planting densities.Through weighted gene coexpression network analysis(WGCNA)analysis,blue and purple modules significantly positively correlated with density tolerant rapeseed were screened.GO enrichment ana-lysis was performed on the genes in the modules,and 12 core transcription factors(including EIN3/EIL1,HD-ZIP,bHLH,NAC,ERF,and TCP)and 1 blue light receptor gene CRY2 were selected from hub genes.Functional annotation showed that multiple core genes corresponding to Arabidopsis thaliana homo-logous genes participated in shade avoidance response.This study can provide data reference and candidate gene resources for improving the density tolerance of rapeseed.