Shen Yi-Guo, Zhang Wan-Ke, Yan Dong-Qing, Du Bao-Xing, Zhang Jin-Song, Liu Qiang, Chen Shou-Yi
Plant Biotechnology Laboratory, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, PR China.
Theor Appl Genet. 2003 Jun;107(1):155-61. doi: 10.1007/s00122-003-1226-z. Epub 2003 Apr 1.
Environmental stresses, such as salinity, drought and cold, can induce the expression of a large amount of genes. Among these are many transcription factors that regulate the expression of downstream genes by specifically binding to cis-elements or forming transcriptional complexes with other proteins. In the present study, a DREB-like transcription factor gene, named AhDREB1, was isolated from a halophyte Atriplex hortensis. AhDREB1 encoded a protein containing a conserved EREBP/AP2 domain featuring the DREB family. In yeast one-hybrid analysis AhDREB1 protein was specifically bound to DRE elements and activated the expression of the reporter genes of HIS3 and LacZ. The AhDREB1 gene was expressed in roots, stems and leaves of A. hortensis. Salinity induced its expression in roots, but not in other organs. Overexpression of AhDREB1 in transgenic tobacco led to the accumulation of its putative downstream genes. The performance of the transgenic lines was also tested under stressed conditions and two lines were found to be stress-tolerant. These results suggest that the AhDREB1 protein functions as a DRE-binding transcription factor and play roles in the stress-tolerant response of A. hortensis.
环境胁迫，如盐度、干旱和寒冷，可诱导大量基因的表达。其中有许多转录因子，它们通过与顺式元件特异性结合或与其他蛋白质形成转录复合物来调节下游基因的表达。在本研究中，从盐生植物滨藜中分离出一个类DREB转录因子基因，命名为AhDREB1。AhDREB1编码一种含有保守的EREBP/AP2结构域的蛋白质，具有DREB家族的特征。在酵母单杂交分析中，AhDREB1蛋白特异性结合DRE元件并激活HIS3和LacZ报告基因的表达。AhDREB1基因在滨藜的根、茎和叶中表达。盐度诱导其在根中表达，但在其他器官中不表达。AhDREB1在转基因烟草中的过表达导致其假定的下游基因积累。还在胁迫条件下测试了转基因株系的性能，发现有两个株系具有耐胁迫性。这些结果表明，AhDREB1蛋白作为一种DRE结合转录因子发挥作用，并在滨藜的耐胁迫反应中起作用。
