Characterization of a DRE-binding transcription factor from a halophyte Atriplex hortensis

• Published in: Theoretical and applied genetics 2003-06, Vol.107 (1), p.155-161
• Main Authors: SHEN, Yi-Guo, ZHANG, Wan-Ke, YAN, Dong-Qing, DU, Bao-Xing, ZHANG, Jin-Song, QIANG LIU, CHEN, Shou-Yi
• Format: Article
• Language: English
• Subjects: Adaptation, Physiological - genetics; Amino Acid Sequence; Arabidopsis; Arabidopsis Proteins; Atriplex - genetics; Biological and medical sciences; Cloning; Dehydrogenases; DNA, Plant - genetics; DNA-Binding Proteins - genetics; Fundamental and applied biological sciences. Psychology; Gene Expression Regulation, Plant; Gene Library; Genes; Genes, Reporter - physiology; Homeodomain Proteins - genetics; Molecular and cellular biology; Molecular Sequence Data; Nicotiana - genetics; Nicotiana - metabolism; Nuclear Proteins - genetics; Plant Leaves - genetics; Plant Leaves - metabolism; Plant Proteins - genetics; Plants, Genetically Modified; Plasmids; Proteins; Saccharomyces cerevisiae; Salinity; Seeds - genetics; Seeds - metabolism; Sequence Homology, Amino Acid; Transcription factors; Transcription Factors - genetics; Transcription Factors - metabolism; Transcriptional Activation; Two-Hybrid System Techniques; Yeast
• ISSN: 0040-5752; 1432-2242
• DOI: 10.1007/s00122-003-1226-z

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.