玉米A亚族bZIP转录因子基因ZmbZIP81的克隆、表达与功能分析

Cloning, Expression, and Functional Analysis of an A Subfamily bZIP Transcription Factor Gene ZmbZIP81 in Maize

碱性亮氨酸拉链(basic leucine zipper,bZIP)蛋白是真核生物所特有的一类转录因子,对于植物在逆境下的基因表达调控具有重要作用。为丰富对玉米bZIP转录因子功能的认识,本研究以从玉米中克隆到的一个A亚族bZIP转录因子编码基因ZmbZIP81为对象展开。ZmbZIP81基因位于玉米第6染色体,编码区全长2492 bp,由4个外显子和3个内含子组成,编码蛋白含254个氨基酸。研究表明ZmbZIP81基因表达受外源ABA、NaCl和干旱胁迫诱导。过表达该基因的拟南芥植物表现出ABA不敏感和NaCl胁迫抗性增强的表型,推测ZmbZIP81可能作为ABA信号途径的负调控因子参与植物抗逆基因表达调控网络。

Basic leucine zipper （bZIP） proteins constitute a large family of transcription factors among eukaryotes, which plays important roles in gene expression regulation under abiotic stress in plants. In order to gain a better understanding of bZIPs in maize, we cloned ZmbZIP81 from maize, which encodes an A subfamily bZIP transcription factor. ZmbZIP81 is located on chro-mosome 6. The coding region of ZmbZIP81 is 2492 bp in length with four exons and three introns, which encodes 254 animo acid residues. Further study showed that the expression of ZmbZIP81 was induced by exogenous ABA, salt and drought treatments. The transgenic Arabidopsis plants overexpressing ZmbZIP81 were less sensitive to ABA, but more tolerant to salt, compared with the wild type. These results indicated that ZmbZIP81 may encode a transcription factor, regulate ABA signaling negatively and participate in abiotic stress tolerance regulation in maize.