基于WGCNA发掘烟草叶片色素代谢途径调控关键转录因子  

Identification of regulatory genes related to pigment synthesis and metabolism by weighted gene correlation network analysis in tobacco leaves

作　　者：冯雨晴 李玉静 赵园园 史宏志[1] FENG Yuqing;LI Yujing;ZHAO Yuanyuan;SHI Hongzhi(College of Tobacco Science Research Center for Tobacco Harm Reduction Tobacco Cultivation Key Laboratory of China Tobacco,Henan Agricultural University,Zhengzhou 450002,China)

机构地区：[1]河南农业大学烟草学院、烟草农业减害研究中心、烟草行业烟草栽培重点实验室,郑州450002

出　　处：《中国烟草学报》2023年第4期54-65,共12页Acta Tabacaria Sinica

基　　金：烟草硝酸盐积累机理及降低硝酸盐含量调节技术研究(TP2019-C4);洱源基地烟叶绿色高效生产技术体系研究与应用(2021450000340021)。

摘　　要：【背景和目的】叶色是影响烟草光合作用及产量的重要性状,为解析烟草不同叶色形成的机制。【方法】以白化突变体(Al)、浅绿突变体(SG)、深绿突变体(DG)和野生型烟草“中烟100”(WT)为材料,进行色素含量测定和转录组研究,并对不同样本间的基因进行加权基因共表达网络分析(weighted gene co-expression network analysis,WGCNA)。【结果】Al和SG两种突变体叶片中叶绿素和类胡萝卜素含量显著低于WT,而深绿突变体叶片中叶绿素和类胡萝卜素含量高于WT。通过WGCNA分析得到了2个与烟草色素含量密切相关的基因共表达模块(darkred模块与色素含量显著正相关,darkolivegreen2模块与色素含量显著负相关)。GO和KEGG富集分析表明,特异性模块可以富集到有生物学意义的富集结果,如光合作用-天线蛋白、核糖体、植物激素信号转导和植物MAPK信号途径等代谢通路。通过计算基因的模块关系值MM,分析挖掘到darkolivegreen2模块中可能与色素含量相关的ERF118转录因子,darkred模块中可能与色素含量相关的ARF1、DIVARICATA、TGA1、WRKY21、AP2和MYC2等转录因子。【结论】转录因子通过调控叶绿体发育和叶绿素代谢影响烟叶色素含量,以上结果为研究烟草叶绿素代谢通路转录调控机制提供了理论基础,为进一步研究不同叶色形成机制提供了线索。[Background]Leaf color is a essential trait closely correlated with the photosynthesis and productivity of tobacco,which is of great importance to understand the formation mechanism of leaf color for regulating photosynthesis and yield of tobacco leaves.[Methods]A stable albino leaf mutant(Al),slight-green leaf mutant(SG)and dark-green leaf mutant(DG)were obtained from the flue-cured tobacco(Nicotiana tabacum L.)cultivar'Zhongyan 100'(ZY100)by mutagenesis with ethyl methanesulfonate(EMS).The differences between the Chl mutants and their wild-type(WT)were analyzed in terms of pigment contents and RNA sequencing(RNA-seq).[Results]Two specific modules were identified in tobacco by weighted gene co-expression network(WGCNA)analysis,in which darkolivegreen2 module was significantly negatively correlated to pigment content,while darkred module was positively significantly correlated to pigment content.GO and KEGG analysis showed that specific modules were significantly enriched in the metabolic process of photosynthetic-antenna protein,ribosome,plant hormone signal transduction,plant MAPK signal pathway and so on.By calculating gene module membership in the networks,the transcription factors that are related to pigment content such as ERF118 in darkolivegreen2 module and ARF1,DIVARICATA,TGA1,WRKY21,AP2,MYC2 in darkred module were identified.[Conclusion]Transcription factors affected the pigment content of leaf by regulating chloroplast development and chlorophyll metabolism.These results provide new candidate genes for studying the transcriptional regulatory mechanism of tobacco chlorophyll metabolic pathway,and offer a clue for further exploration of the formation mechanism of leaf color.

关 键 词：烟草 叶色突变体 加权基因共表达网络 转录因子 

分 类 号：S572[农业科学—烟草工业]