利用NCBI茶树转录组数据库,以铁观音芽叶为材料,克隆了茶树细胞色素P450基因CYP71A26与CYP71B34的cDNA全长。CYP71A26与CYP71B34的cDNA全长分别为1β879βbp和1β764βbp,分别含有1β539βbp（编码513个氨基酸）和1β533βbp（编码511个氨基酸）的完整开发阅读框。氨基酸序列比对结果显示,CYP71A26与CYP71B34的同源性为42.47%,为2个亚家族基因。氨基酸结构分析表明,2个基因均具有植物P450的螺旋C（Helix C）、螺线I（Helix I）、螺线K（Helix K）、“Meander”区域序列和血红素结合域（Heme binding domain）的典型结构。进化树分析显示,CYP71A26与CYP71B34在分子进化树上分属两大分支,2个基因与其他物种亲缘关系的远近不同。三级结构模拟与功能域分析显示,CYP71A26与CYP71B34主要由N端的β折叠和C端的α螺旋结构组成,且2个基因均具有一个P450蛋白结构域（Pfam domain）。荧光定量PCR结果表明,CYP71A26与CYP71B34基因在不同茶树害虫为害的叶片中,分别表现出上调和下调表达的现象。而在冷热环境下,CYP71A26与CYP71B34基因分别表现出下调和上调表达的现象。表明茶树CYP71A26与CYP71B34基因均参与了生物（害虫）与非生物（温度）的胁迫响应,但两个基因表达相反,参与环节可能相反。
The full cDNA sequences of cytochrome P450 genes, CYP71A26 and CYP71B34 were cloned from Camellia sinensis Tieguanyin leaves based on NCBI transcriptome database. The complete cDNA lengths of CYP71A26 and CYP71B34 were 1β879βbp and 1β764βbp, containing the open reading frames (ORF) of 1β539βbp and 1β533βbp, which encoded 513 and 511 amino acids, respectively. The alignment of amino acid sequences showed 42.47% of conservation between CYP71A26 and CYP71B34, which indicated that the two genes belonged to different subfamilies. The structure analysis showed that both CYP71A26 and CYP71B34 contained the classic P450 structure domains, such as helix C, helix I, helix K, Meander and heme binding domain. Phylogenetic tree analysis illustrated that there were two branches of molecular evolution for the two genes with different genetic relationship. Via predicting of their tertiary structures and functional domains, the results indicated that both genes were constituted by β-pleated structure in N-terminal, α-helix structure in C-terminal, and had a P450 protein structure domain (Pfam domain). qRT-PCR results showed that the expression of two genes in leaves showed opposite trends under pest damage treatments. Moreover, the decrease of CYP71A26 and increase of CYP71B34 in expression levels were detected under cold or thermal stresses. In total, CYP71A26 and CYP71B34 genes were respond to biotic (like pest) and abiotic (like temperature) stresses, but the changing trends of the two genes were opposite, which might be correlated with opposite regulation systems.
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