海岛棉GbMFT2基因能提高烟草的耐盐能力  

Gossypium barbadense GbMFT2 Can Improve Salt-Resistant Capability in Tobacco

作　　者：李超[1] 蔡大润[1] 顾超[1] 黄先忠[1,2] 

机构地区：[1]石河子大学生命科学学院,农业生物技术重点实验室,石河子832003 [2]美国佐治亚大学,植物基因组图谱实验室,雅典30605

出　　处：《分子植物育种》2015年第5期1009-1016,共8页Molecular Plant Breeding

基　　金：国家自然科学基金(31360366);新世纪优秀人才支持计划项目(NCET-12-1072);新疆研究生创新项目(XJGRI2013063)共同资助

摘　　要：MOTHER OF FT AND TFL1(MFT)属于磷脂酰乙醇胺结合蛋白(phosphatidyl ethanolamine-binding protein,PEBP)家族,该家族在被子植物中主要起着促进或抑制开花和控制株型的作用。本课题组前期从海岛棉(Gossypium barbadense)中克隆了一个MFT-like同源基因GbMFT2,发现其在种子中表达量较高,并且受ABA诱导。为了进一步探究该基因的功能,本研究首先检测了200 mmol/L Na Cl胁迫海岛棉0、1 h、3 h、6 h、12 h后基因的表达量,表明在盐诱导1 h GbMFT2基因的表达量最高。然后构建了过量表达载体p35S:GbMFT2,并通过农杆菌介导的叶盘法将其转化到普通烟草(Nicotiana tabacum cv.NC89)中,半定量RT-PCR表明GbMFT2基因在烟草中异位表达成功。利用0、100 mmol/L、200 mmol/L、300 mmol/L、400 mmol/L和500 mmol/L Na Cl胁迫不同的转基因株系,表明转基因烟草比野生型烟草更耐盐。再分别测量300 mmol/L Na Cl处理前后的野生型烟草和转基因烟草的脯氨酸含量、POD活性,发现处理后的野生型烟草的脯氨酸含量、POD活性均明显降低,而转基因烟草株系中的脯氨酸含量、POD活性均有明显的提升。研究结果表明,GbMFT2基因能够响应盐胁迫,并增加烟草的耐盐性。本研究可为研究植物MFT-like基因的功能提供了新思路,也为进一步解析棉花发育基因的功能提供了研究基础。MOTHER OF FT AND TFL1（MFT） belongs to phosphatidyl ethanolamine-binding protein（PEBP）family. The PEBP family plays an important role in promoting or inhibiting flowering, as well as plants architecture control. A homologous gene named GbMFT2 has been cloned from Gossypium barbadense by our group previously, which has been proved to be expressed highly in seeds and the expression of GbMFT2 can be induced by ABA. To study the function of GbMFT2 further, expression levels of GbMFT2 in Gossypium barbadense, which was treated with 200 mmol/L Na Cl for 0, 1 h, 3 h, 6 h and 12 h, were detected in this study firstly. The result indicated that expression of GbMFT2 was induced by salt, and with a maximum after 1 h treatment. Then we constructed an overexpression vector of p35S：GbMFT2 under the Ca MV35 S promoter, and transformed it into Nicotiana tabacum cv. NC89 by Agrobacterium tumefaciens-mediated leaf-disc method.Semi-quantitative RT-PCR analysis indicated that GbMFT2 expressed in transgenic tobacco lines successfully.Different transgenic lines treated by 0, 100 mmol/L, 200 mmol/L, 300 mmol/L, 400 mmol/L and 500 mmol/L Na Cl showed higher salt tolerance than wild-type tobacco. The proline content and POD activity in wild-type and transgenic tobaccos were determined before and after 300 mmol/L Na Cl treatment, respectively. The results indicated that both of proline content and POD activity were declined obviously in wild-type tobacco after salt stress, whereas the two physiological symptoms were both increased in transgenic tobacco lines. In summary, the results proved that GbMFT2 could response to salt stress and increase the salt tolerance of tobacco. This study provided a new idea to explore the function of MFT-like genes, and played a foundation for further analysis of the functions of flowering development genes in cotton.

关 键 词：MFT-like GbMFT2基因 烟草转化 耐盐 海岛棉 

分 类 号：S572[农业科学—烟草工业]