启动子对外源基因在转基因植物中表达的影响  

Directed Duplication of CaMV35S Promoter Influerues the Expression of the Foreign Genes in Transgenic Plants

作　　者：晏小兰 邱国华[1] 李宝健[1] 徐增富[1] 

机构地区：[1]中山大学生物工程研究中心 [2]广州市教育学院生物学系

出　　处：《中山大学学报（自然科学版）》1995年第2期60-67,共8页Acta Scientiarum Naturalium Universitatis Sunyatseni

摘　　要：将来自ｐＢＩ１２１质粒的ＣａＭＶ３５Ｓ启动子片段插入到ｐＢＩ１２１的ＣａＭＶ３５Ｓ启动子与ＧＵＳ基因之间，构建了串联的ＣａＭＶ３５Ｓ启动子载体ｐＬＢ３８．通过三亲交配，将ｐＢＩ１２１及ｐＬＢ３８分别转移到含ｐＧｖ３８５０的农杆菌中，成为适合本研究的双元载体。以叶圆盘转化法将外源基因转入烟草，获得了２种转基因植株。经ＤＮＡ分子杂交、ＮＰＴⅡ点分析、ＧＵＳ荧光定性及定量分析，证明外源基因已整合进烟草基因组并获得表达。ｐＬＢ３８的ＧＵＳ表达量为ｎＢｌ１２１的３～４倍，这表明启动子数目的不同会直接影响其启动基因的表达水平。The mediated vector pLB38 was constructed by insertion the 800 bp fragment of CaMV35S promoter from the plasmid pBI 121 into the BamH I site between the CaMV 35S pro- moter and GUS gene of the pBI121 and screening the recombinants containing the directed dupli- cate of CaMV35S promoter with Xba I digest.The plasmid pBI121 and pLB38 were introduced into the Agrobacterium tumefaciens containing Ti plasmid pGV 3850 by triparental-mating tech- nique with the aid of helper plasmid pGJ23. The foreign genes in pLB38 and pBI121 were transferred into the tobcco plants using the leaf -disk co-cultivated method and two kinds transgenic plants were obtained. DNA / DNA dot blot and Southern blot with α-32P labelled probe containing 3kb fragment of CaMV 35S-GUS comfirmed that foreign genes were transferred and integrated into the trans- genic tobacco plant genome,The identification of the product of NPT II gene with NPT II dot as- say,GUS gene with GUS fluorescent assay proved that the foreign NPT II and GUS gene were expressed in transgenic plants.And the GUS activity in pLB38-transformed plants in which the GUS gene was controlled by two directed CaMV35S promoters was three-to four-fold higher than that in the pBI121-transformed plants in which the GUS gene is controlled by single CaMV35S promoter.These results suggested that the promoter number has effect on the expres- sion level of genes controlledy by these promoters.

关 键 词：启动子 基因表达 外源基因 转基因植物 基因工程 

分 类 号：Q78[生物学—分子生物学]