甘蓝型油菜叶片白化分子机理研究  

Molecular Mechanisms of Albino Leaves in Brassica napus

作　　者：叶沈华 马晓伟 杨杰 李嘉欣 赵伦 易斌 马朝芝 涂金星[1] 沈金雄[1] 傅廷栋[1] 文静[1] YE Shen-hua;MA Xiao-wei;YANG Jie;LI Jia-xin;ZHAO Lun;YI Bin;MA Chao-zhi;TU Jin-xing;SHEN Jin-xiong;FU Ting-dong;WEN Jing(College of Plant Science and Technology of Huazhong Agricultural University,National Research Center of Rapeseed Engineering and Technology,Wuhan 430070)

机构地区：[1]华中农业大学植物科学技术学院,国家油菜工程技术研究中心,武汉430070

出　　处：《植物遗传资源学报》2023年第3期875-888,共14页Journal of Plant Genetic Resources

基　　金：国家现代农业产业技术体系(CARS-12);国家重点研发计划项目(2017YFD0101702)。

摘　　要：叶色突变体是研究色素代谢和叶绿体发育机制的重要种质资源。为解析甘蓝型油菜温度敏感型白叶突变体形成的分子机制,本研究对两个甘蓝型油菜人工合成种姊妹系绿叶株系G7097和白叶株系W7105进行了生理指标测定和转录组分析。在冬季低温条件下,W7105白叶的叶绿素和类胡萝卜素含量显著减少,叶绿体发育异常。与绿叶相比,白叶的净光合速率(Pn)显著降低,细胞间CO_(2)浓度(Ci)显著升高。在3个不同发育时期摘取G7097和W7105叶片进行转录组测序,共检测到1532个与叶色相关的差异表达基因(DEGs),包括540个上调的差异表达基因和992个下调的差异表达基因。GO和KEGG富集分析结果显示,W7105白化叶片中上调的差异表达基因显著富集在蛋白酶体、翻译过程、碳水化合物和能量代谢途径;而下调的差异表达基因则与叶绿体、光合作用和电子传递链显著相关。参与叶绿素和类胡萝卜素生物合成的多个基因在W7105白叶中下调表达,证实白化叶片中叶绿素和类胡萝卜素代谢也受到了影响。研究结果为进一步定位和克隆甘蓝型油菜叶片白化关键基因以及阐述油菜白叶形成的分子机制提供了一定参考。Leaf-color mutants are crucial germplasms for deciphering the mechanisms of pigment metabolism and chloroplast development.In this study,to uncover the mechanisms of temperature-sensitive albino phenotype in Brassica napus,the physiological assessment and transcriptome analysis were performed in two resynthesized B.napus inbred lines,the white-leaf line W7105 and its green-leaf sibling line G7097.Under low temperature in field conditions,in albino leaves of W7105,the chlorophyll and carotenoid content were dramatically decreased and chloroplast structure was abnormal.Compared with green leaves,albino leaves showed significantly lower net photosynthetic rate(Pn)and significantly higher intercellular CO_(2) concentration(Ci).Transcriptome analysis of leaves at three different developing stages was performed in G7097 and W7105 lines.After pairwise comparisons,a total of 1532 differentially expressed genes(DEGs)associated with leaf color phenotype were identified,including 540 and 992 genes that were up-regulated and down-regulated,respectively.GO and KEGG enrichment analysis showed that the up-regulated DEGs in albino leaves of W7105 were significantly enriched in proteasome,translation process,carbohydrate and energy metabolism pathways;while the down-regulated DEGs were significantly enriched in chloroplasts,photosynthesis and electron transport chain.Moreover,several DEGs in chlorophyll and carotenoid biosynthesis were significantly downregulated in albino leaves,suggesting that chlorophyll and carotenoid metabolisms were also impaired.Collectively,these findings provide references for further delimiting the candidate genes and uncovering the molecular mechanisms of albino leaves in B.napus.

关 键 词：白化 甘蓝型油菜 叶色 叶绿体发育 转录组 

分 类 号：S565.4[农业科学—作物学]