摘要
植物在逆境下能合成甜菜碱,其中磷酸乙醇胺N-甲基转移酶(PEAMT)和胆碱单加氧酶(CMO)是甜菜碱合成过程中的关键酶。将盐角草SePEAMT基因、SeCMO基因以及烟草的核基质结合区序列(Mar)利用Cre/loxP重组系统构建到同一表达载体上,得到植物表达载体pYLTAC747N-Mar-SePEAMT-SeCMO-Mar。该载体用电击转化法转入农杆菌EHA105中,通过农杆菌介导法转化烟草,经PCR检测确定转基因植株。在含250mM NaCl的MS培养基上培养35天后,转基因植株生根而野生型植株不能生根;转基因烟草植株甜菜碱积累量显著高于野生型植株,约是野生型植株的5.6～7.7倍;转基因植株与野生型相比,相对电导率显著降低,叶绿素含量明显升高。以上结果表明共表达SePEAMT和SeCMO能有效提高烟草甜菜碱表达量从而提高烟草的耐盐性。
In plants, betaine is synthesized upon abiotic stress, in which phosphoethanolamine N-methyltransferase（PEAMT） and choline monooxygenase（CMO） are key enzymes. A plant expression vector pYLTAC747N-Mar-SePEAMT-SeCOM-Mar, which includes SePEAMT gene and SeCMO gene cloned from Salicornia europaea, and the matrix attachment region （Mar） isolated from tobacco, was obtained based on Cre/ LoxP recombination system. The resultant plasmid was transferred into Agrobacterium tumefaeiens EHA105 by the electroporation method, then transferred into tobacco （Nictiana tabacum L. cv. 89） via Agrobaeterium-mediated method. PCR analysis showed that genes were transformed successfully into the transgenic plants. In the condition of NaCl stress for 35d, the transgenic plants could root while the wild-type plants could not. The glycine betaine content of transgenic plants was significantly higher than wild type plants, and the glycine betaine content of transgenic plants was about 5.6-7.7 fold of wild plants. Transgenic plants exhibit significantly lower relative conductivity and higher content of chlorophyll. The data suggest that co-expression of SePEAMT and SeCMO might increase the glycine betaine content and improve the salinity tolerance of engineered plants.
出处
《中国农学通报》
CSCD
北大核心
2010年第9期55-59,共5页
Chinese Agricultural Science Bulletin
基金
辽宁省科技攻关"农业生物技术"(2006208001)
