马尾松CAD基因的克隆及其编码蛋白质的结构预测

Cloning and Coding Protein Structure Prediction on cDNA Encoding Cinnamyl Alcohol Dehydrogenase from Pinus massoniana

肉桂醇脱氢酶(cinnamyl alcoholdehy drogenase,CAD)在木质素合成过程中起关键作用。本研究利用CODEHOP设计简并引物,采用RT-PCR和RACE技术,从马尾松中克隆得到CAD基因的cDNA全长(GenBank登入号:KF419291)。此cDNA全长1 450 bp,包括1 074 bp完整的ORF,编码357个氨基酸的蛋白,相对分子质量与等电点分别为38945.1u和5.8。利用ClustalX、DNAMAN、ANTHEPROT软件分析其序列和编码的氨基酸序列。采用RT-PCR方法对CAD基因在根、侧枝、叶、芽四种组织中表达的特异性分析,结果显示,CAD基因在马尾松侧枝中表达量最高,在叶、根和芽中亦有低水平表达。

Cinnamyl alcohol dehydrogenase（CAD） plays a key role in lignin biosynthesis. In the paper, we used CODEHOP to design the degenerate primers online, the CADgenes from Pinus massoniana（GenBank accession number： KF419291） was cloned through RT-PCR and SMART RACE RT-PCR. The CAD of Pinus massoniana,whose length is 1 450 bp, contained an open reading frame of 1 074 bp which encoded a polypeptide of 357 amino acids with predicted molecular mass of 38945.1u and PI of 5.8. Its nucleotide sequences and the encoded amino acid sequences were analyzed with the softwares of ClustalX, DNAMAN, ANTHEPROT. Tissue specific expression showed that CAD expressed in stem was much higher than in leaf, root and shoot from Pinus massoniana.