花生AhSOS2基因的克隆及功能初探  

Cloning and Functional Characterization of Peanut Gene AhSOS2

作　　者：张国嘉[1,2] 侯蕾[2] 王庆国[2] 徐建第 李臻[2] 刘晓[2] 戴绍军[1] 刘炜[2] 

机构地区：[1]东北林业大学盐碱地生物资源环境研究中心/东北油田盐碱植被恢复与重建教育部重点实验室,黑龙江哈尔滨150040 [2]山东省农业科学院生物技术研究中心/山东省作物遗传改良与生态生理重点实验室,山东济南250100 [3]山东省水稻研究所,山东济南250100

出　　处：《作物学报》2014年第3期405-415,共11页Acta Agronomica Sinica

基　　金：国家转基因生物新品种培育重大专项(2009ZX08001-010B);山东省农业良种工程(2012–2014)资助

摘　　要：SOS2(Salt Overly Sensitive 2)作为植物中一类重要的耐盐相关基因,在调控细胞内离子平衡及参与植物对盐害的响应及适应过程中具有重要作用。本研究通过RACE的方法,从花生叶片中分离到一长1462 bp、包含1341 bp开放阅读框(ORF)的cDNA片段,生物信息学分析显示,该基因属SOS2类基因,被命名为AhSOS2(GenBank登录号为HG797656),编码446个氨基酸,为丝氨酸/苏氨酸蛋白激酶。对基因表达特性的荧光定量PCR分析显示,AhSOS2在花生中为组成型表达;且受盐胁迫及干旱诱导。经250 mmol L–1 NaCl处理后,该基因在花生幼苗茎中被诱导表达,表达量约是对照茎中的30倍;而在30%PEG-6000模拟干旱处理下,该基因在花生幼苗叶中表达量也明显升高。综合以上结果,显示AhSOS2可能参与并调控花生对逆境的抗性及耐受性。目前,已成功构建了AhSOS2的植物双元表达载体pCAMBIA1301P-AhSOS2并获得转基因植株,初步功能分析显示,过表达AhSOS2基因的转基因水稻对盐胁迫的耐受性提高。预期这方面的工作对于解析花生对盐害、干旱等逆境的适应及防御机制,进而指导花生抗性育种及品质改良具有重要意义。SOS2 （Salt Overly Sensitive 2） is a kind of important salt tolerance genes, which is involved in mediating the intracellular ion balance and plays an important role in the response of plants to salt damage and adaptation. In this study, a 1462 bp full-length cDNA, including a 1341 bp open reading frame, was isolated and harvested by RACE method. As the gene showed more than 70% homologous to members of SOS2 subfamily in other plants by bioinformatics analysis, it is then named as AhSOS2 （GenBank accession numberHG797656）. Its coding protein AhSOS2 has 446 amino acids, and is a member of serine/threonine protein kinases. Quantitative real-time PCR （qRT-PCR） analysis showed that AhSOS2 was expressed constitutively in peanut tissues, and could be induced to express higher under salt and drought treatments. When treated with 250 mmol L-1 NaCl, the gene expression level increased dramatically to about 30 times higher than that of control in the stems of peanut seedlings, while the expression level of AhSOS2 increased markedly in the leaves of peanut seedlings when treated by drought stress that imitated by 30% PEG-6000.AhSOS2 is supposed to participate in stress resistance and tolerance in peanut. The expression binary vector of pCAMBIA1301P-AhSOS2 was constructed and the transgenic rice plants were obtained. The primary functional verification showed that the ability of salt tolerance and adaptation was enhanced in AhSOS2 overexpression rice. The above research is expected to uncover the adversity defense mechanisms of peanut grown under stress conditions, and further guide the resistance breeding and quality improvement of peanut.

关 键 词：花生 SOS2类基因AhSOS2 荧光定量PCR 表达特性 抗逆 品质改良 

分 类 号：S565.2[农业科学—作物学]