葡萄VvMET1-1基因在葡萄和拟南芥中的功能研究

Functional Studies of VvMET1-1 Gene in Grapevine and Arabidopsis thaliana

DNA甲基化修饰对于植物的生长发育十分重要,而MET1是植物中重要的甲基转移酶,能维持植物的CG位点甲基化修饰。为了研究葡萄MET1基因的功能及对植物发育的影响,将葡萄VvMET1-1基因转入葡萄胚性愈伤组织和拟南芥中进行研究。本研究选择35S::VvMET1-1-GFP表达载体转入葡萄胚性愈伤组织后检测到明显的GFP信号,且该胚性愈伤组织能被成功诱导为体细胞胚,表明VvMET1-1首次被成功转入葡萄胚性愈伤组织中并且不影响胚性愈伤组织的发育和分化。VvMET1-1被转入拟南芥中发现,该基因能影响拟南芥叶片的长度和宽度,但是不影响植株形态和种子发育;转录组数据分析表明,许多逆境胁迫、生长素、种子萌发、果实成熟、脱落酸和茉莉酸合成相关的基因差异表达;甲基化组结果显示,拟南芥过表达VvMET1-1后CG和CHH位点甲基化水平分别发生了明显的上调和下调,且DNA甲基化差异区(DMR)的类型主要是CG和CHH型,因此推测VvMET1-1可能通过调控DNA甲基化水平的变化影响下游基因的表达,进而调控拟南芥的生长发育。

DNA methylation modification is important for plant growth and development,and MET1 is an important methyltransferase that maintains CG site methylation modification in plants.To investigate the function of grape MET1 gene and its effect on plant development,grape VvMET1-1 gene was transferred into grape embryogenic callus and Arabidopsis thaliana.In this study,after transferring 35S::VvMET1-1-GFP expression vector into grape embryogenic callus,obvious GFP signal was detected,and embryogenic callus could be successfully induced into somatic embryo,indicating that VvMET1-1 has been successfully transferred into grape embryogenic callus for the first time without affecting the development and differentiation of embryogenic callus.VvMET1-1 was transferred to Arabidopsis thaliana and found to affect leaf length and width,but not plant morphology or seed development.Transcriptome data analysis showed that many genes,such as stress,auxin,seed germination,fruit ripening,abscisic acid and jasmonic acid synthesis related to genes,were differentially expressed.Methylation analysis indicated that the methylation levels of CG and CHH were significantly up-regulated and down-regulated,and the anchored genes mainly occurred in the methylated regions of CG and CHH sequences.Therefore,it is speculated that VvMET1-1 may affect the expression of downstream genes through methylation levels changes,and thus regulate growth and development of Arabidopsis thaliana.