《植物生理学报》 2016, 52(10): 1537-1545

茄子MnSOD基因的克隆及表达分析

徐龙, 陈火英, 蒋明敏, 刘杨^*

上海交通大学农业与生物学院, 上海200240

通信作者：刘；E-mail: liuyangtl@sjtu.edu.cn

摘　要：

以茄子品种‘禾线’为材料, 采用同源克隆方法从茄子中克隆获得一个MnSOD基因, 其开放阅读框全长为687 bp, 编码228个氨基酸, 将其命名为SmMnSOD。序列分析表明, SmMnSOD与辣椒MnSOD序列相似性达到91%, 与番茄MnSOD序列相似性达到84%。预测该蛋白质分子量为25.63 kDa, 蛋白等电点为8.46。亚细胞定位结果显示, MnSOD蛋白定位于线粒体。实时荧光定量PCR表明, SmMnSOD在不同组织器官中均有表达, 但在叶片中表达量最多, 其次为花瓣和根, 果肉中最少。在NaCl胁迫下, SmMnSOD表达量呈现先上升后下降趋势; 聚乙二醇胁迫抑制了SmMnSOD的表达; 外源脱落酸胁迫下, SmMnSOD的表达量是波动变化的; 低温胁迫极显著地抑制了SmMnSOD的表达。实验结果证明, SmMnSOD主要在茄子叶片、花瓣和根中表达, 在线粒体中发挥功效, 可能与茄子抵御渗透性胁迫和干旱胁迫相关。

关键词：茄子; MnSOD; 基因克隆; 亚细胞定位; 实时荧光定量PCR

收稿：2016-06-02   修定：2016-09-26

资助：国家自然科学基金(31301770和31471870)和上海市科技兴农项目[沪农科种字(2013)第5号]。

Cloning and expression analysis of MnSOD from Solanum melongena

XU Long, CHEN Huo-Ying, JIANG Ming-Min, LIU Yang^*

School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China

Corresponding author: LIU Yang; E-mail: liuyangtl@sjtu.edu.cn

Abstract:

A cDNA of MnSOD gene was cloned from Solanum melongena using homology-based cloning method. The full open reading frame length of SmMnSOD is 687 bp, encoding a MnSOD precursor of 228 amino acids. Sequence analysis shows that 91% identity with MnSOD in pepper and 84% with tomato. The molecular weight of this protein was 25.63 kDa and protein isoelectric point is at pI 8.46. The result of subcellular localization indicated that MnSOD protein was located in mitochondrion. The results of real time PCR indicated that the expression level of SmMnSOD was the highest in leaves, followed by petals and roots, and the least in sarcocarp. The expression of SmMnSOD under stress of NaCl was up-regulated firstly and then declined. Polyethylene glycol (PEG) down-regulated the expression of SmMnSOD. The expression of SmMnSOD was fluctuating due to the effect of abscisic acid (ABA). Under low temperature stress, the expression of SmMnSOD was significantly inhibited. In conclusion, SmMnSOD was mainly expressed in the leaves, petals and roots of eggplant, and played a function in the mitochondrion. It may be related to the resistance to osmotic stress and drought stress in eggplant.

Key words: eggplant (Solanum melongena); MnSOD; gene cloning; subcellular localization; real time PCR