Cotton GhDREB1 increases plant tolerance to low temperature and is negatively regulated by gibberellic acid.
The transcription factors C-repeat binding factors/dehydration-responsive element binding proteins (CBFs/DREBs) control the expression of many stress-inducible genes in Arabidopsis. A cDNA clone, designated GhDREB1, was isolated from cotton (Gossypium hirsutum) by cDNA library screening. Northern blot analysis indicated that mRNA accumulation of GhDREB1 was induced by low temperatures and salt stress, but was not induced by abscisic acid (ABA) or drought stress in cotton seedlings. Transgenic tobacco (Nicotiana tabacum) plants overexpressing GhDREB1 displayed stronger chilling tolerance than wild-type plants. Their leaf chlorophyll fluorescence, net photosynthetic rate and proline concentrations were higher than those of control plants during low-temperature treatment. However, under normal growth conditions, the transgenic tobacco plants exhibited retarded growth and delayed flowering. Interestingly, GhDREB1 transcripts in cotton seedlings were negatively regulated by gibberellic acid (GA(3)) treatment. Analysis of the promoter of the GhDREB1 gene revealed the presence of one low-temperature and four gibberellin-responsive elements. Green fluorescent protein (GFP) signal intensity or beta-glucuronidase (GUS) activity driven by the GhDREB1 promoter was clearly enhanced by low temperature but repressed by GA(3). These results suggest that GhDREB1 functions as a transcription factor and plays an important role in improving cold tolerance, and also affects plant growth and development via GA(3).
Shan
Da-Peng
DP
Huang
Jin-Guang
JG
Yang
Yu-Tao
YT
State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, Shandong 271018, China.
Guo
Ying-Hui
YH
State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, Shandong 271018, China.
Wu
Chang-Ai
CA
State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, Shandong 271018, China.
Yang
Guo-Dong
GD
State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, Shandong 271018, China.
Gao
Zheng
Z
State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, Shandong 271018, China.
Zheng
Cheng-Chao
CC
State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Taian, Shandong 271018, China.
D000595:Amino Acid Sequence; D002467:Cell Nucleus / Q000378:metabolism; D003080:Cold Temperature; D035264:Flowers / Q000235:genetics / Q000254:growth & development; D018506:Gene Expression Regulation, Plant / Q000187:drug effects*; D015723:Gene Library; D005875:Gibberellins / Q000494:pharmacology*; D003368:Gossypium / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D030821:Plants, Genetically Modified / Q000254:growth & development / Q000502:physiology; D011401:Promoter Regions, Genetic; D016415:Sequence Alignment; D014026:Nicotiana / Q000235:genetics / Q000254:growth & development; D014157:Transcription Factors / Q000737:chemistry / Q000235:genetics / Q000502:physiology*