杨树叶绿体3′rps12基因,rps7基因和ndhB基因片段的克隆及序列分析

通过烟草叶绿体相关序列设计引物 ,从杨树的叶绿体基因组中克隆出 2个相邻的DNA片段 .经分析发现 ,这 2个DNA片段包含核糖体蛋白 3′rps12、rps7基因和NADH脱氢酶第二亚基ndhB基因片段 .利用DNAMAN等软件 ,将扩增到的杨树叶绿体DNA片段与烟草、拟南芥、玉米和黑松的相关序列进行比较 ,证实所扩增的片段具有较高的保守性 ,尤其是在这 3个基因的编码区 ,同源性均在 90 %以上 .插入或缺失常发生在基因间隔区 ,同源性在 80 %左右 ;对其编码区所推导的氨基酸序列进行了比较 ,同源性均在 92 %以上 .首次克隆了杨树叶绿体的部分DNA序列 ,详细报道并分析了杨树 3′rps12、rps7基因和ndhB基因片段及其边界序列信息 .所报告的基因序列均已登录GenBank .

Cloning and Sequence Analysis of 3'rps12,rps7 and ndhB Genes from Chloroplast Genome of Populus tomentosa

Two DNA fragments were amplified from the chloroplast genome of Populus tomentosa by the primers designed from tobacco chloroplast genome.These two amplified DNA fragments included ribosomal protein genes 3′ rps 12 and rps 7,the gene fragment of the second subunit of NADH dehydrogenase( ndh B),and their flanking sequences.Softwares such as DNAMAN were used to analyze the homology between the amplified fragments and the corresponding sequences of tobacco,arabidopsis,maize and black pine.It was demonstrated that the cloned fragments were very conserved,especially in the coding regions of the three genes,and the homology could reach up to 90%.Insertion and deletion often happened in the inter\|regions of the coding genes,in which homology was around 80%.In addition,amino acid sequences deduced from the encoding region of the cloned genes were also analyzed.The homology of the amino acid among the four or five plants could get to 92%.It is the first time to report cloning DNA sequences from the chloroplast genome of Populus tomentosa. The cloned genes,3′ rps 12, rps 7, ndh B,and their flanking sequeces were analyzed in detail.The sequence data repoted here have been deposited in GenBank.