转录因子OsHOX4过量表达及T1代转基因植株中纯合系鉴定

Overexpression of Transcription Factor Oshox4 from Rice and Deter-mination of Homozygosis Plants in T_1 Generation

OsHOX4基因是属于水稻植物同源结构域(HD-Zip)转录因子家族的一个成员。本研究利用农杆菌介导法将OsHOX4基因转入籼稻(Oryza sativa ssp.indica)IR64中,获得54株过量表达植株。我们利用southern杂交分析确定了各个株系的拷贝数后,利用TAIL-PCR方法对4个不同的单拷贝株系进行了研究,并在其中找出T-DNA在3个单拷贝株系染色体上的插入位点(分别为染色体5,8,10)。根据T-DNA在各个株系的插入位点分别设计特异性引物,从T1代转基因株系里鉴定出纯合的植株。我们观察到OsHOX4过量表达植株的分蘖数明显高于野生型,株高比野生型明显的变矮,在同一个株系的纯合和杂合的转基因植株表型也有很大的差异。在TAIL-PCR分析基础上,为从T1代转基因作物中鉴定出纯合的植株提供了方法和理论依据。

OsHOX4 gene is a member of plant homeodomain-leucine zipper （HD-Zip） family of transcription factors. In this study, OsHOX4 gene was introduced into rice IR64 variety with Agrobacterium tumefaciens-mediated transformation, and obtained 54 OsHOX4 over expressed independent lines. After the copy numbers of these transgenic plants were confirmed with southern blotting analysis, four independent single copy lines were analyzed with the TAIL-PCR technique, and from them T-DNA insert positions in the chromosome of three lines were identified （in chromosome 10, 5, 8 respectively）. Depending on T-DNA insert position in chromosome of each transgenic single copy line, specific primers were designed, and homozygous plants from T1 transgenic lines were easily identified. We observed that the tiller number of OsHOX4 over expressed transgenic plants is higher than that of wild type, but plant height is shorter than that of wild type, and between homozygous transgenic plants and heterozygous transgenic plants in same line, there are also big phenotype differences. Depending on TAIL-PCR technique, our research provides a easy method and a theoretical basis for the determination ofhomozygous plants from T1 generation transgenic plants.