title: Overexpression of two chrysanthemum DgDREB1 group genes causing delayed flowering or dwarfism in Arabidopsis.
abstract: We isolated 13 DREB1 (dehydration responsive element binding factor 1) genes from chrysanthemum and further divided them into three groups, DgDREB1A, DgDREB1B and DgDREB1C, based on the phylogenetic analysis. Each group showed their unique expression patterns under cold, dehydration and salt stress conditions. Arabidopsis plants overexpressing DgDREB1A (1A plants) exhibited significantly stronger tolerance to freezing and drought than those overexpressing DgDREB1B (1B plants) and the control plants. In addition, 1A plants showed delayed flowering, but not dwarfism; while 1B plants showed dwarfism, but not delayed flowering. In 1A plants, the expression of three stress-related DREB1-downstream genes, COR47, COR15A, and RD29A, was strongly induced while the expression of CO and FT, two photoperiod responsive flowering-time genes, was inhibited. In 1B plants, the expression of GA2ox7, a GA-deactivation enzyme gene, was dramatically enhanced. The results above strongly suggest that members from different DgDREB1 groups may have distinct effects on plant development: DgDREB1A may be involved in photoperiod-related flowering-time determination and DgDREB1B in GA-mediated plant development.
authors: Department of Ornamental Horticulture, China Agricultural University, Beijing, China.
authors: Zheng
authors: Z
authors: Tong
authors: Bo
authors: B
authors: Hong
authors: Yingjie
authors: Y
authors: Yang
authors: Qiuhua
authors: Q
authors: Li
authors: Nan
authors: N
authors: Ma
authors: Chao
authors: C
authors: Ma
authors: Junping
authors: J
authors: Gao
mesh_terms: D017360:Arabidopsis / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics*; D031202:Chrysanthemum / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D017931:DNA Primers; D018076:DNA, Complementary / Q000235:genetics; D018744:DNA, Plant / Q000235:genetics; D035264:Flowers / Q000254:growth & development*; D018506:Gene Expression Regulation, Plant; D010935:Plant Diseases / Q000235:genetics; D010940:Plant Proteins / Q000235:genetics; D030821:Plants, Genetically Modified / Q000235:genetics; D014157:Transcription Factors / Q000235:genetics*
chemical_list: D029681:Arabidopsis Proteins; D017931:DNA Primers; D018076:DNA, Complementary; D018744:DNA, Plant; C114578:DREB1A protein, Arabidopsis; D010940:Plant Proteins; D014157:Transcription Factors