National Key Facility of Crop Gene Resources and Genetic Improvement/Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, People's Republic of China.
Plant Cell Rep. 2012 Dec;31(12):2229-38. doi: 10.1007/s00299-012-1332-y. Epub 2012 Aug 22.
Seven kinds of transgenic tobacco plants transformed with combinations of three FBE genes were obtained. The transgenic plants transformed with Ta1-SST + Ta6-SFT genes appeared to have the highest fructan or soluble sugar content and the strongest salt tolerance. Fructan is thought to be one of the important regulators involved in plant tolerance to various abiotic stresses. In this study, wheat-derived genes, Ta1-SST, Ta6-SFT, and Ta1-FFT, encoding fructan biosynthesis enzymes (FBE) were isolated and cloned into vectors modified pBI121 or pZP211. Seven different combinations of the three target genes were transformed into tobacco plants through an Agrobacterium-mediated approach, and transgenic tobacco plants were identified by PCR, ELISA, and Southern blotting. Compared with tobacco plants transformed with other six combinations of the three target genes and with wild-type plants, the transgenic plants transformed with Ta1-SST + Ta6-SFT genes contained the highest fructan and soluble sugar content. All seven types of transgenic tobacco plants displayed a much higher level of tolerance to drought, low temperature, and high salinity compared with the wild type. Differences of drought and low temperature tolerance between the transgenic plants containing a single FBE gene and those harboring two or three FBE genes were not significant, but the salt tolerance level of the transgenic plants with different FBE gene combinations from high to low was: Ta1-SST + Ta6-SFT > Ta1-SST + Ta6-SFT + Ta1-FFT > Ta1-SST + Ta1-FFT > Ta1-SFT + Ta1-FFT > single FBE gene. These results indicated that the tolerances of the transgenic tobacco plants to various abiotic stresses were associated with the transformed target gene combinations and the contents of fructan and soluble sugar contained in the transgenic plants.
获得了 7 种转有三种 FBE 基因组合的转基因烟草植株。转 Ta1-SST + Ta6-SFT 基因的转基因植株的果聚糖或可溶性糖含量最高，耐盐性最强。果聚糖被认为是参与植物耐受各种非生物胁迫的重要调节因子之一。在本研究中，从小麦中分离并克隆了编码果糖合成酶（FBE）的 Ta1-SST、Ta6-SFT 和 Ta1-FFT 基因，这些基因被导入到经过修饰的 pBI121 或 pZP211 载体中。通过农杆菌介导的方法将这三种目的基因的七种不同组合转化到烟草植株中，通过 PCR、ELISA 和 Southern 印迹法鉴定转化的烟草植株。与转其他六种目的基因组合和野生型烟草植株的烟草植株相比，转 Ta1-SST + Ta6-SFT 基因的烟草植株的果聚糖和可溶性糖含量最高。与野生型相比，七种类型的转基因烟草植株对干旱、低温和高盐的耐受性均明显提高。含有单个 FBE 基因的转基因植株与含有两个或三个 FBE 基因的转基因植株之间的耐旱性和耐寒性差异不显著，但不同 FBE 基因组合的转基因植株的耐盐性水平从高到低依次为：Ta1-SST + Ta6-SFT > Ta1-SST + Ta6-SFT + Ta1-FFT > Ta1-SST + Ta1-FFT > Ta1-SFT + Ta1-FFT > 单个 FBE 基因。这些结果表明，转基因烟草植株对各种非生物胁迫的耐受性与转化的目的基因组合以及转基因植株中果聚糖和可溶性糖的含量有关。
