LsICE1基因表达及调控转基因水稻抗冷通路研究

Expression of LsICE1 Gene and Its Regulation Function of Cold Responsive Signalling Pathway in Transgenic Rice

LsICE1基因是从生菜中分离的一个低温胁迫转录因子,过表达LsICE1基因的转基因水稻提高了抗寒能力。LsICE1基因在生菜的根、茎、叶中为组成型表达,其中叶的表达量较强。LsICE1基因的表达水平能被冷、ABA和NaCl处理所上调,但不被脱水处理上调。卡方测验表明,转基因T1水稻潮霉素抗性发生了3∶1抗性分离模式,大多数转基因植株中LsICE1基因是以单拷贝、单位点整合到水稻基因组中。Southern和Northern杂交检测结果表明,3个抗冷的转基因株系中LsICE1基因均是以单拷贝、单位点整合到水稻基因组中,并正常表达。冷胁迫下,LsICE1基因的超表达对水稻的OsDREB1A基因影响较大,表明LsICE1基因对转基因水稻抗寒性影响依赖OsDREB1冷反应通路。

LslCE1 gene, a cold stress transcription factor, was isolated from lettuce, and overexpression of LslCE1 gene improved low temperature stress tolerant capacities in transgenic rice lines. LslCE1 was expressed constitutively in the examined tissues, such as the roots, stems and leaves, and LslCE1 gene mRNA levels were dominant in leaves of lettuce seedling. The expression levels of LslCE1 were upregulated by cold, ABA, NaC1 treatments, but not by the dehydration treatment, x2test showed that the transgenic T1 rice plants presented hygromycin resistant segregation model for 3：1 ratio, suggesting that LslCE1 gene was integrated into the genome of most of To transgenic plants by single copy mode. The Southern and Northern blot analysises showed that LslCE1 gene had been integrated into the genome of three cold- resitant To transgenie lines, and expressed normally. After cold stress, overexpression of LslCE1 gene had significant effect on the expression of OsDREB1A, suggesting that the function of LslCE1 in cold stress was dependent of the OsDREB1 cold responsive signalling pathway in transgenic rice.