《植物生理学报》 2015, 51(4): 481-487

玉米NADP⁺-异柠檬酸脱氢酶基因克隆和特征分析

袁进成*, 宋晋辉*, 瓮巧云, 马海莲, 王凌云, 刘颖慧**

河北北方学院农林科技学院, 河北张家口075000

通信作者： 刘颖慧；E-mail: leely519@126.com；Tel: 0313-4029309

摘　要：

异柠檬酸脱氢酶(IDH)是三羧酸循环中最关键和最有意义的限速酶, 在生物体的三羧酸循环代谢反应中起重要的作用。我们从玉米中克隆了一个新的异柠檬酸脱氢酶基因, 命名为ZmIDH2并对其特征进行初步研究。ZmIDH2基因全长1 643 bp, 开放阅读框1 236 bp, 编码412个氨基酸, 同时克隆了IDH2基因组DNA, 全长3 463 bp, 具有11个内含子和12个外显子。进化树分析表明该基因在生物进化中高度保守, 与植物的细胞质IDH2基因的亲缘关系较近。半定量RT-PCR结果显示ZmIDH2基因在玉米中是组成型表达的, 在根和幼胚中的表达量较高。胁迫处理玉米植株, 表明在干旱和高盐条件下ZmIDH2基因表达量明显提高, ZmIDH2酶活性也受盐和干旱诱导。

关键词：异柠檬酸脱氢酶基因; 玉米; 克隆; 特征; 胁迫

收稿：2014-12-29   修定：2015-02-15

资助：国家自然科学基金(31101155)、“十二五”农村领域国家科技计划项目(2011BAD06B01)和河北北方学院重大项目(ZD201305)。

Cloning and Character Analysis of NADP⁺-Dependent Isocitrate Dehydrogenase Gene in Maize

YUAN Jin-Cheng*, SONG Jin-Hui*, WENG Qiao-Yun, MA Hai-Lian, WANG Ling-Yun, LIU Ying-Hui**

College of Agriculture and Forestry, Heibei North University, Zhangjiakou, Hebei 075000, China

Corresponding author: YUAN Jin-Cheng; E-mail: leely519@126.com; Tel: 0313-4029309

Abstract:

NADP⁺-dependent isocitrate dehydrogenase (IDH) catalyzes the reversible conversion of isocitrate to α-ketoglutarate and plays an essential rate-limiting step in the citric acid cycle. In this report a cytosolic NADP⁺ dependent isocitrate dehydrogenase gene from maize has been cloned. The analysis of the nucleotide sequence revealed an open reading frame of 1 236 bp and encoding 412 amino acids. The ZmIDH2 had a 12-extron/11-intron genomic structure and a genomic length of 3 463 bp. The amino acid sequence displayed high homology with those from other plants such as rice and Arabidopsis. The gene was transcripted in all tissues tested, with the high amount of ZmIDH2 transcript being found in root and embryo. Semi RT-PCR and enzyme active analyses showed that ZmIDH2 was induced by drought and salt stress both in transcription and enzyme level.

Key words: ZmIDH2; maize; clone; character; stress