Characterization of OfWRKY3, a transcription factor that positively regulates the carotenoid cleavage dioxygenase gene OfCCD4 in Osmanthus fragrans.
The sweet osmanthus carotenoid cleavage dioxygenase 4 (OfCCD4) cleaves carotenoids such as β-carotene and zeaxanthin to yield β-ionone. OfCCD4 is a member of the CCD gene family, and its promoter contains a W-box palindrome with two reversely oriented TGAC repeats, which are the proposed binding sites of WRKY transcription factors. We isolated three WRKY cDNAs from the petal of Osmanthus fragrans. One of them, OfWRKY3, encodes a protein containing two WRKY domains and two zinc finger motifs. OfWRKY3 and OfCCD4 had nearly identical expression profile in petals of 'Dangui' and 'Yingui' at different flowering stages and showed similar expression patterns in petals treated by salicylic acid, jasmonic acid and abscisic acid. Activation of OfCCD4pro:GUS by OfWRKY3 was detected in coinfiltrated tobacco leaves and very weak GUS activity was detected in control tissues, indicating that OfWRKY3 can interact with the OfCCD4 promoter. Yeast one-hybrid and electrophoretic mobility shift assay showed that OfWRKY3 was able to bind to the W-box palindrome motif present in the OfCCD4 promoter. These results suggest that OfWRKY3 is a positive regulator of the OfCCD4 gene, and might partly account for the biosynthesis of β-ionone in sweet osmanthus.
School of Life Sciences, State Key Laboratory of Cotton Biology, Key Laboratory of Plant Stress Biology, Laboratory of Plant Germplasm and Genetic Engineering, Henan University, Kaifeng, 475004, Henan, China.
Yuanji
Y
Han
School of Life Sciences, State Key Laboratory of Cotton Biology, Key Laboratory of Plant Stress Biology, Laboratory of Plant Germplasm and Genetic Engineering, Henan University, Kaifeng, 475004, Henan, China.
Miao
M
Wu
School of Life Sciences, State Key Laboratory of Cotton Biology, Key Laboratory of Plant Stress Biology, Laboratory of Plant Germplasm and Genetic Engineering, Henan University, Kaifeng, 475004, Henan, China.
Liya
L
Cao
School of Life Sciences, State Key Laboratory of Cotton Biology, Key Laboratory of Plant Stress Biology, Laboratory of Plant Germplasm and Genetic Engineering, Henan University, Kaifeng, 475004, Henan, China.
Wangjun
W
Yuan
School of Life Sciences, State Key Laboratory of Cotton Biology, Key Laboratory of Plant Stress Biology, Laboratory of Plant Germplasm and Genetic Engineering, Henan University, Kaifeng, 475004, Henan, China.
Meifang
M
Dong
School of Life Sciences, State Key Laboratory of Cotton Biology, Key Laboratory of Plant Stress Biology, Laboratory of Plant Germplasm and Genetic Engineering, Henan University, Kaifeng, 475004, Henan, China.
Xiaohui
X
Wang
School of Life Sciences, State Key Laboratory of Cotton Biology, Key Laboratory of Plant Stress Biology, Laboratory of Plant Germplasm and Genetic Engineering, Henan University, Kaifeng, 475004, Henan, China.
Weicai
W
Chen
School of Life Sciences, State Key Laboratory of Cotton Biology, Key Laboratory of Plant Stress Biology, Laboratory of Plant Germplasm and Genetic Engineering, Henan University, Kaifeng, 475004, Henan, China. fudeshang@henu.edu.cn.
Fude
F
Shang
D000595:Amino Acid Sequence; D001483:Base Sequence; D002338:Carotenoids / Q000378:metabolism*; D002467:Cell Nucleus / Q000378:metabolism; D018076:DNA, Complementary / Q000235:genetics / Q000302:isolation & purification; D018744:DNA, Plant / Q000235:genetics; D049308:Dioxygenases / Q000235:genetics* / Q000378:metabolism; D035264:Flowers / Q000235:genetics; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D029592:Oleaceae / Q000201:enzymology* / Q000235:genetics*; D018515:Plant Leaves / Q000235:genetics; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D021381:Protein Transport; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D014026:Nicotiana / Q000235:genetics; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D015854:Up-Regulation / Q000235:genetics
D018076:DNA, Complementary; D018744:DNA, Plant; D010940:Plant Proteins; D012333:RNA, Messenger; D014157:Transcription Factors; D002338:Carotenoids; D049308:Dioxygenases
Carotenoid cleavage dioxygenase; Osmanthus fragrans; WRKY transcription factor