中文摘要：

【目的】克隆玉米ZmBTF3b并研究其参与逆境反应的分子机制,为揭示玉米抗逆分子机制奠定基础。【方法】应用生物信息学方法分析ZmBTF3b启动子序列特点;应用酵母单杂交方法验证该基因编码转录因子的转录激活活性;应用实时荧光定量PCR方法分析ZmBTF3b在玉米不同组织中的表达差异及其在非生物胁迫下的表达模式。【结果】从玉米抗旱自交系CN165中克隆得到干旱诱导表达基因ZmBTF3b,该基因编码蛋白含有169个氨基酸,具有新生多肽复合体（nascent polypeptide-associated complex,NAC）保守结构域;酵母单杂交试验证明ZmBTF3b具有转录激活功能;实时荧光定量PCR结果表明,ZmBTF3b在玉米花丝、幼穗、幼胚中表达量较高。ZmBTF3b受脱水干旱胁迫和PEG模拟干旱胁迫诱导根上调表达,而受冷、NaCl、ABA和SA诱导下调表达。【结论】ZmBTF3b编码蛋白具有转录因子的基本特性,在应答逆境胁迫特别是干旱胁迫时起重要作用。

英文摘要：

【Objective】 ZmBTF3b gene was cloned and used to analyze the expression profiles under abiotic stresses,providing a foundation for investigating mechanisms of molecular regulation in stress tolerance in maize. 【Method】 The promoter of ZmBTF3b was analyzed via bioinformatics. Transcriptional activation activity of ZmBTF3b was conducted using yeast one-hybrid system. Expression profiles of ZmBTF3b in different tissues of maize and in response to abiotic stresses were assayed via real-time quantitative PCR （qRT-PCR）. 【Result】 The cloned ZmBTF3b gene encoded a putative transcription factor of 169 amino acids with a conserved NAC （nascent polypeptide-associated complex） domain. Transcriptional activity analysis showed that ZmBTF3b might be a functional transcription factor. Real-time quantitative PCR （qRT-PCR） analysis revealed that ZmBTF3b was highly expressed in silks,ears and immature embryos and was up-regulated under dehydration or PEG treatment while was down-regulated under cold,NaCl,ABA or SA. 【Conclusion】 ZmBTF3b might have the transcriptional activation activity and play an essential role in response to abiotic stresses.