RNAi抑制萝卜过氧化物酶基因的效果受光照影响  

Effect of Light on RNAi Silencing of Peroxidase in Chinese Red Radish

作　　者：王丽[1] 王曦烨[1] 彭方林[1] 李日辉[1] 李迎迎[1] 袁园园[1] 王林嵩[1] 

机构地区：[1]河南师范大学生命科学学院,河南新乡453007

出　　处：《中国生物化学与分子生物学报》2015年第4期391-396,共6页Chinese Journal of Biochemistry and Molecular Biology

基　　金：河南省教育厅科学技术研究重点项目(No.12A180017)资助~~

摘　　要：农杆菌介导的RNAi技术已广泛应用于研究植物基因的功能.本实验应用小块萝卜肉质根体外培养,探讨光照对干扰萝卜过氧化物酶基因Rsprx1表达的影响.结果表明,干扰萝卜过氧化物酶基因Rsprx1表达后,抑制组中过氧化物酶活性显著低于对照组,光照减弱RNAi的抑制作用;抑制作用始于浸染后4 h,过氧化物酶活性减低时,花青素含量增加,但光照增加花青素含量;HPLC结果显示,与对照组比,抑制组中花青素苷种类和含量有较大差异;花青素合成相关基因(Rs CHS、Rs DFR和Rs LDOX)的mRNA水平在处理后明显上调.此外,过氧化氢酶活性和H2O2含量相应升高.由此表明,光照可影响农杆菌介导的RNAi效果,干扰萝卜过氧化物酶基因Rsprx1表达可以通过影响花青素合成相关基因的表达和过氧化氢含量,从而影响花青素代谢.RNA interference（RNAi） using Agrobacterium rhizogen-mediated transformation has been used to study gene function in plants.In the present study,the influence of light on the silencing of peroxidase（POD） gene Rsprx1 in Chinese red radish was investigated.The results from fleshy root tissue culture system showed that inhibiting Rsprx1 expression in root tissues following RNAi significantly reduced the POD activity as compared to the control.Such inhibitory effect was weakened by light at 4hours after transformation.The anthocyanidin content was increased as the POD activity declined,and continued to accumulate in light.The HPLC chromatograms revealed differences in the component and concentration of anthocyanidin between Rsprx1-RNAi root tissue and the control.The relative expression levels of anthocyanin biosynthesis genes,such as chalcone synthase（CHS）,dihydroflavonol 4-reductase（DFR）,leucoanthocyanidin dioxygenase（LDOX） were up-regulated in Rsprx1-RNAi root tissues.In addition,the catalase activity and hydrogen peroxide content were increased.We concluded that light affected the transformation efficiency of Agrobacterium rhizogenes-mediated RNAi.Down-regulating Rs Prx1 transcript level can affect anthocyanidin metabolism through changing the expression level of anthocyanin biosynthesis genes and the content of hydrogen peroxide.

关 键 词：过氧化物酶 花青素 RNA干扰 光照 次生代谢 

分 类 号：Q554.6[生物学—生物化学]