[目的]从能源植物象草中克隆出参与木质素生物合成的肉桂酰辅酶A还原酶基因(CCR)的cDNA序列及全长DNA序列,进而分析其序列特征。[方法]采用传统RT-PCR及RACE技术克隆象草CCR序列,并利用NCBI,ProtParam,ProtScale,TMHMM,TargetP,SignalP,Pfam20.0,Prosite,Swiss-Model和ClustalW2等在线分析程序以及DNAman,DNAstar和MEGA5软件对得到的序列进行生物信息学分析。[结果]克隆得到了象草CCR包含编码区和3'非翻译区的长为1316bp的cDNA序列以及包含5个外显子和4个内含子的全长为6133bp的DNA序列。通过生物信息学分析得知,象草CCR基因编码长为369个氨基酸的蛋白,该蛋白二级结构元件以无规则卷曲和α-螺旋为主,属于依赖NAD表异构酶/脱氢酶家族,其辅助因子结合区域和底物结合位点高度保守。[结论]成功从象草中克隆出肉桂酰辅酶A还原酶基因。它具有CCR同源基因典型的特征。获得的各种生物信息学数据为今后开展此酶的深入研究以及对象草的更好利用提供了一定的理论参考价值。
[Objective] The aim was to clone the cDNA and DNA sequences of the CCR (Cinnamoyl-CoA reductase) gene which involves in lignin biosynthesis, from Pennisetum purpureum, and to make comprehensive analysis on these sequences. [Method] CCR sequences were cloned from P. purpureum by using conventional RT-PCR and RACE (Rapid Amplification of cDNA Ends) methods; and the bioinformatic analyses of the CCR were conducted by means of NCBI, ProtParam ProtScale, TMHMM, TargetP, SignalP, Pfam20.0, Prosite, Swiss-Model, ClustalW2, DNAman, DNAstar and MEGA5. [Result] The cloned PpCCR (P. purpureum CCR) cDNA sequence was 1 316 bp, including a 1 110 bp ORF and 206 bp 3’-UTR. The cloned DNA sequence from PpCCR was 6 133 bp in full-length, containing five exons and four introns. Bioinformatic analysis indicated that PpCCR encoded a polypeptide of 369 amino acids, the secondary structure of which was primarily composed of random coil and α-helix, belonging to NAD-dependent epimerase/dehydratase family, and its co-factor binding sites and substrate binding sites were highly conserved. [Conclusion] DNA and cDNA sequences of CCR gene were obtained from P. purpureum, which had the typical characteristics of other homologous genes. The obtained bioinformatic data provided theoretical references for the further analysis of CCR and better application of P. purpureum in the future.