林麝是我国一级保护动物,广西是其分布的最南缘,但目前境内资源已相当稀少.为了更好地了解这一物种,我们扩增林麝线粒体基因组并对其序列结构进行初步分析.其全序列长16354bp,包含13个蛋白质编码基因,22个转运RNA(transfer RNA,tRNA)基因,2个核糖体RNA(ribosomal RNA,rRNA)基因和一个控制区,各基因的排列顺序和绝大多数哺乳动物是一致的.林麝线粒体基因绝大部分密码子使用典型的脊椎动物模式,但是我们发现2个稀有的启动密码子,其中一个ATA启动ND2基因和ND3基因,另一个ATT启动ND5基因.控制区位于tRNA-Pro和tRNA-Phe基因之间,由924个碱基组成.在控制区,二个延伸终止序列(ETAS)和二个保守"模块"(CSB)被鉴定.轻链复制的起点(OL)由35个碱基组成,位于一个由5个tRNA基因串联组成的区域(WANCY区)内,形成一个茎环结构.线粒体基因组序列结构分析显示,林麝与鹿科动物有更近的亲缘关系.
Forest musk deer(Moschus berezovskii) were once distributed widely in China,and Guangxi Autonomous Region was their southmost habitate.However,forest musk deer are becoming critically endangered at present.In the present study,the structure of the complete mitochondrial genome of forest musk deer was analyzed.It revealed that the organization of the mitochondrial genome in the forest musk deer was consistent with that of other reported mammals.The complete mitochondrial DNA is 16354 bp in length and contains two ribosomal RNA genes,thirteen protein-coding genes,twenty-two transfer RNA genes and one control region(CR).Most codon usage also followed the typical pattern of vertebrates.Two rare start codons were found,in which ATA initiated the NADH dehydrogenase subunit-2(ND2) gene and subunit-3(ND3) gene,and ATT initiated the ND5 gene.The control region is located between the tRNA-Pro and tRNA-Phe genes and is 924 bp.Two conserved sequence blocks(CSB) and two extended termination associated sequence(ETAS) were identified within this region.The origin of L-strand replication(OL) in M.berezovskii mitochondrion is located in a cluster of five tRNA genes(WANCY region) with 35 nucleotides in length.The analysis of mitochondrial genome indicates that the forest musk deer share a closer relationship with cervids