茶树两个 Dof 转录因子的分离及其在温度胁迫中的响应分析

摘要

茶树是一种重要的经济作物，温度胁迫对茶叶生产影响较大。本研究以茶树品种迎霜为实验材料，克隆获得2个编码 Dof 转录因子的基因 CsDof1和 CsDof2。序列分析显示，CsDof1含有1389 bp，编码463个氨基酸；CsDof2含有1458 bp，编码486个氨基酸。CsDof1和 CsDof2转录因子都具有典型的锌指结构域，分别位于第133~195和124~186个氨基酸位点之间。对 CsDof1和 CsDof2转录因子理化性质、亲/疏水性、二级和三级结构分析显示，两者都是亲水性蛋白且显偏碱性。空间结构分析显示，CsDof1和 CsDof2均有1个α-螺旋，且 Dof 结构域的位点完全相同，均有4个半胱氨酸残基。实时定量 PCR 表明，CsDof1和 CsDof2在不同茶树品种、不同温度胁迫下均能诱导表达，且表达呈现差异。%Tea is an important economic crop. Tea production is affected by temperature factors. CsDof1 and CsDof2, which encode Dof transcription factors, were cloned from tea cultivar ‘Yingshuang’ [Camellia sinensis (L.) O. Kuntze]. The nucleotide and amino acid sequences, phylogenetic tree and molecular models of the CsDof1 and CsDof2 were analyzed. The results showed that the CsDof1 and CsDof2 are 1389 and 1458 nucleotides in length, which encode 463 and 486 amino acids respectively. Typical zinc finger domains are present in both CsDof1 and CsDof2, from coden 133 to 195 and 124 to 186 respectively. The CsDof1 and CsDof2 were hydrophilic proteins. The three-dimensional structures of CsDof1 and CsDof2 indicated the presence of a highly conserved Dof domain with four cysteine residues. Quantitative real-time PCR analysis showed that CsDof1 and CsDof2 were induced by different temperature stresses and the expression profiles were different among tea cultivars.