Xue Hua, Yang Yu-Tao, Wu Chang-Ai, Yang Guo-Dong, Zhang Meng-Meng, Zheng Cheng-Chao
College of Life Sciences, Shandong Agricultural University, 61 Daizong Street, Taian, Shandong, 271018, People's Republic of China.
Theor Appl Genet. 2005 Feb;110(4):620-7. doi: 10.1007/s00122-004-1880-9. Epub 2005 Jan 20.
Nuclear matrix attachment regions (MARs) are thought to influence the expression of the flanking genes. TM2, a new DNA fragment isolated from tobacco, can bind with the rice nuclear matrix in vitro. In this study, we investigated the effect of TM2 on transgene expression under the control of three different promoters in stably transformed rice calli and plants. The presence of TM2 flanking the transgene increased the expression of constructs based on the constitutive CaMV 35S and maize ubiquitin gene promoters in both resistant calli and transformed plants. The GUS expression directed by the photosynthetic-tissue-specific PNZIP promoter was also increased in photosynthetic tissues of transformants. However, TM2 did not change the gene expression pattern controlled by the PNZIP promoter. The effect of TM2 in transgenic plants was stronger than that in transgenic calli based on all three promoters. Our results indicate that TM2, as a novel strong MAR, can be used to increase the transgene expression levels in the whole plant or in particular tissues of monocotyledons.
核基质附着区（MARs）被认为会影响侧翼基因的表达。TM2是从烟草中分离出的一个新的DNA片段，它在体外能与水稻核基质结合。在本研究中，我们调查了TM2对稳定转化的水稻愈伤组织和植株中三种不同启动子控制下的转基因表达的影响。转基因侧翼存在TM2会增加基于组成型花椰菜花叶病毒35S和玉米泛素基因启动子构建体在抗性愈伤组织和转化植株中的表达。由光合组织特异性PNZIP启动子指导的GUS表达在转化体的光合组织中也有所增加。然而，TM2并没有改变由PNZIP启动子控制的基因表达模式。基于所有三种启动子，TM2在转基因植株中的作用比在转基因愈伤组织中更强。我们的结果表明，TM2作为一种新型的强MAR，可用于提高单子叶植物全株或特定组织中的转基因表达水平。
