摘要
To compare the transformation effects of two different forms （cDNA in monocotyledonous plant Echinochloa crusgalli, DNA in monocotyledonous plant Zea mays） of phosphoenolpyruvate carboxylase （PEPC） gene （Ppc） on the growth of transgenic dicotyledonous plant, Agrobacterium-mediated transformation of Ppc genes into Nicotiana tabacum were carried out. Transgenic leaf plates and differentiated seedling leaves were verified by GUS histochemistry, PCR, and RT-PCR. Results showed that transgenic N. tabacum with Ppc-cDNA of E. crusgalli had relatively strong differentiation ability. However, N. tabacum after transformation of complete DNA sequence of Ppc genes in Z mays had relatively poor ability of growth. The differentiated green seedlings had the phenomenon of yellowing; and photosynthesis ability of leaves was poor. This might be caused by the misidentification and wrong splicing in transcription. This indicated that the expression rate of monocotyledonous complete DNA might be reduced in the monocotyledonous cells with relatively far genetic distances. Detection results of showed that Pn in most transgenic N. tabacum with Ppc-cDNA of E. crusgalli was was higher than that in control, which preliminarily proved that PEPC of monocotyledonous plant E. crusgalli had certain regulatory effects on photosynthesis of N. tabacum.
为比较单子叶植物2种不同形式(cDNA和DNA)的磷酸烯醇式丙酮酸羧化酶(phosphoenolpyruvate earboxylase,PEPC)基因(Ppc)对双子叶植物的转化效果,本研究将单子叶植物稗草(Echinochloa crusgalli)Ppc基因的cDNA和玉米(Zea mays)Ppc基因的DNA全长通过农杆菌介导对双子叶植物烟草(Nicotiana tabacum)进行了遗传转化:对转化叶盘和分化苗幼叶进行的GUS组织化学染色、PCR、RT-PCR检测结果证明,2种形式的Ppe基因均转入了烟草中:对分化幼苗进一步的培养观察结果发现:转Ppc基因cDNA的烟草分化苗生长发育正常,而转Ppc基因DNA的分化幼苗在培养过程中叶片白化现象严重,未完成正常生长发育过程,可能是由于完整基因DNA在异源细胞中在转录过程中发生了不正确的起始或锚误的拼接,导致基因表达异常。由此推测遗传距离较大的物种间转移DNA基因序列全长可能会降低正常表达率,而转稗草Ppc基因cDNA的大部分烟草植株的Pn高于对照,结果证明单子叶稗草根型PEPC酶对烟草的光合作用具有一定的调节作用。
基金
Supported by the Innovation Project of Chinese Academy of Agricultural Sciences~~
