甘蔗胁迫诱导表达基因ScCBF1的功能分析

摘要

以甘蔗苗为材料研究了甘蔗CBF1转录激活因子ScCBF1在水杨酸(SA)、茉莉酸甲酯(MeJA)以及重金属镉(CdCl2)和铜(CuCl2)胁迫下的表达情况;将ScCBF1的原核表达载体pGEX-6P-1-ScCBF1转化大肠杆菌(Escherichia coli)Rosetta(DE3),检测其在NaCl、PEG8000胁迫下的生长情况.结果表明:ScCBF1在MeJA、SA、CdCl2以及CuCl2逆境胁迫下表达下调;在500 mmolL-1 NaCl胁迫下,含有重组质粒的细胞生长速度显著减缓,不同浓度NaCl胁迫下的平板胁迫结果进一步说明了ScCBF1基因不具耐盐性;在15%PEG8000胁迫下,含有重组质粒细胞的生长速度明显高于对照,不同浓度PEG8000胁迫下的平板胁迫结果说明了ScCBF1基因在应答干旱胁迫中具有抗逆性.构建了ScCBF1的植物表达载体pCAMBIA1301-ScCBF1并通过农杆菌侵染在本氏烟叶片中瞬时表达,在4℃低温胁迫下,T0代烟草植株长势显著优于对照.%To investigate the functions of ScCBF1 in alleviating salicylic acid ( SA) , methyl jasmonate ( MeJA) , heavy metal cad-mium ( Cd) and copper ( Cu) stress, prokaryotic expression vector pGEX-6P-1-ScCBF1 was transformed into Rosetta ( DE3) strain ( Escherichia coli) in sugarcane seedlings, then the growth rate of transformed cell lines was investigated under NaCl and PEG8000 stress. The results showed that ScCBF1 was significantly down-regulated under the treatments of SA, MeJA, CdCl2 or CuCl2 , respec-tively. With 500 mmolL-1 NaCl, growth rates of cells containing the recombinant plasmid significantly slowed down. Further spot assay under different concentrations of NaCl confirmed that ScCBF1 was susceptible to NaCl. The growth of Rosetta/pGEX-6P-1-Sc-CBF1 cells was faster in LB liquid medium containing 15% PEG8000 compared to that of the control. Spot assay also revealed that ScCBF1 was resistant to drought stress. Moreover, the over expression vector of pCAMBIA-1301-ScCBF1 was constructed successful-ly and then was transformed into the leaves of Nicotiana benthamiana by Agrobacterium-mediated method. Transient expression of Sc-CBF1 in the tobacco plants confirmed that T0 generation plants with expressed ScCBF1 was more resistant to cold than the control under 4 ℃.