转PSAG12-BAS1基因抑制烟草叶片的衰老  

PSAG12-BAS1 Gene Transformed into Tobacco(Nicotiana tabacum) for Inhibition of Leaf Senescence

作　　者：姚新转 吕立堂[1,2] 赵德刚[1,2] YAO Xin-Zhuan LV Li-Tang ZHAO De-Gangla(Institute of Agro-Bioengineering, College of Life Sciences, Guizhou University, Guiyang 550025, China The Key Laboratory of Plant Resources Conservation and Germplasm Innovation in Mountainous Region, Ministry of Education, Guizhou University, Guiyang 550025, China)

机构地区：[1]贵州大学生命科学学院/农业生物工程研究院,贵阳550025 [2]贵州大学山地植物资源保护与种质创新省部共建教育部重点实验室,贵阳550025

出　　处：《农业生物技术学报》2016年第12期1831-1838,共8页Journal of Agricultural Biotechnology

基　　金：国家自然科学基金(No.31160149);国家转基因生物新品种培育科技重大专项(No.2014ZX08010-003);外源基因删除技术及其在转基因生物新品种培育中的应用(No.2016ZX08010003-009);高产优质香糯新组合选育及配套栽培技术研究(黔科合NZ字[2012]3009号)

摘　　要：衰老被认为是烟草（Nicotiana tabacum）叶片发育的最后阶段,伴随着叶绿素,脂类等降解,严重影响了光合产物的积累,导致作物产量降低、品质下降。因此,利用转基因技术使烟草在生长期间衰老延迟,光合产物量增加,从而增加产量,同时在收获之后,延缓衰老的叶片,可以维持烟草的新鲜程度,解决储存及运输问题。本研究利用农杆菌（Agrobacterium tumefaciens）介导的遗传转化法将含有衰老相关基因12（senescence-associated gene 12,SAG12）启动子驱动光敏色素B激活标签的抑制蛋白1（phy B activationtagged suppressor1,BAS1）基因表达的元件导入烟草中,经抗性筛选和PCR鉴定,共获得45株转基因植株,其中有8株转基因烟草叶片具有衰老延缓现象。在叶片开始衰老时对野生型和转BAS1基因烟草叶片叶绿素含量、保护酶活性检测以及植物生长期状态进行观察测定,结果表明,转BAS1烟草植株叶绿素含量从顶端到基部均高于野生型;野生型和转BAS1基因烟草超氧化物歧化酶（super-oxide dismutase,SOD）活性和丙二醛（malondialdehyde,MDA）含量分析表明,转BAS1烟草植株中SOD活性比野生型高了31.98%,MDA含量比野生型降低了48.28%,通过对烟草生长发育过程观察,转基因烟草比野生型烟草衰老延缓10-15 d。在烟草叶片开始衰老时测定野生型和转BAS1基因植物细胞分裂素含量,结果发现,野生型烟草细胞分裂素的含量比转基因烟草降低了40.2%,上述结果说明,转BAS1基因延缓了烟草叶片的衰老,与细胞分裂素含量、保护性酶活性提高以及衰老性启动子启动有关。本研究为进一步研究SAG12-BAS1基因功能机制提供理论依据,同时该基因为创制转基因抗衰老材料提供了基础。Senescence, regarded as the last stage of tobacco leaf development, seriously affects the accumulation of the photosynthetic products along with degradation of chlorophyll and lipid, resulting in the decrease of the yield and the quality of the crop. Transgenic technology is an important technical means to cultivate new varieties with high yield and resistance, which is helpful to increase the yield of the unit area of the tobacco（Nicotiana tabacum）. During the growth of tobacco, the delay of senescence can increase the amount of photosynthetic products, which could increase the yield of crop. After harvesting, senescence delay of the leaves can keep the freshness of tobacco, so as to solve the problem of storage and transportation.Therefore, research on leaf senescence regulation has a very important significance in agricultural production.In this work, the Agrobacterium- mediated transformation method were adopted to introduce BAS1（phy B activation- tagged suppressor 1） gene driven by the SAG12 promoter into tobacco and 45 SAG12- BAS1 trangenic plants were obtained according to the result of resistance screening and PCR identification. Among these transgenic plants, eight transgenic tobacco plants showed that their leaves senility were delayed. Leaf chlorophyll content, protective enzyme activity and plant growth phase were observed and measured on the wild type and transgenic SAG12- BAS1 tobacco leaves during leaf senescence. The results showed that the chlorophyll content of transgenic SAG12-BAS1 tobacco plants was higher than that of the wild type from the top to the base. The results of content analysis of super-oxide dismutase（SOD） and malondialdehyde（MDA）investigated between the wild type and transgenic SAG12- BAS1 tobacco demonstrated that SOD activity in transgenic SAG12- BAS1 tobacco plants was 31.98 % higher than that of wild type and the content of MDA was 48.28% lower than that of the wild type. The conclusion that the senescence of transgenic tobacco delayed for 10-15 d than that of

关 键 词：衰老特异启动子-光敏色素B激活标签的抑制蛋白1基因(PSAG12-BAS1) 细胞分裂素 叶绿素含量 保护性酶活 延缓衰老 

分 类 号：S572[农业科学—烟草工业]