斐豹蛱蝶线粒体基因组全序列的测定和分析(英文)

该研究对斐豹蛱蝶(Argyreus hyperbius)(鳞翅目:蛱蝶科)线粒体基因组全序列进行了测定和初步分析。结果表明:斐豹蛱蝶线粒体基因全序列全长为15156bp,包含13个蛋白质编码基因、22个tRNA和2个rRNA基因以及1个非编码的A+T富集区,基因排列顺序与其它鳞翅目种类一致;线粒体全序列核苷酸组成和密码子使用显示出明显的A+T偏好(80.8%)和轻微的AT偏移(AT skew,?0.019)。基因组中共存在11个2～52bp不等的基因间隔区,总长96bp;以及14个1～8bp不等的基因重叠区,总长34bp。除COI以CGA作为起始密码子外,13个蛋白质编码基因中的其余12个基因是以ATN作为起始密码子。除COI和COII基因是以单独的一个T为终止密码子,其余11个蛋白质编码基因都是以TAA结尾的。除了缺少DHU臂的tRNASer(AGN),其余的tRNA基因都显示典型的三叶草结构。tRNA(AGN)和ND1之间的基因间隔区包含一个ATACTAA结构域,这个结构域在鳞翅目中是保守的。A+T富集区没有较大的多拷贝重复序列,但是包含一些微小重复结构:ATAGA结构域下游的20bp poly-T结构,ATTTA结构域后的(AT)9重复,以及位于tRNAMet上游的5bp poly-A结构等。这项研究所揭示的斐豹蛱蝶的线粒体基因组特征,不仅为认识蛱蝶科的遗传多样性贡献数据,而且对于该物种的保护生物学、群体遗传学、谱系地理及演化研究等具有重要意义。

Complete mitochondrial genome of the laced fritillary Argyreus hyperbius (Lepidoptera: Nymphalidae)

We investigated the complete mitochondrial genome (mitogenome) of A rgyreus hyperbius.The 15156 bp long genome harbored the gene content (13 protein coding genes,22 tRNA genes,2 rRNA genes and an A+T-rich region) and the gene arrangement was identical to all known lepidopteran mitogenomes.Mitogenome sequence nucleotide organization and codon usage analyses showed that the genome had a strong A+T bias,accounting for A+T content of 80.8％,with a small negative AT skew (-0.019).Eleven intergenic spacers totaling 96 bp,and t4 overlapping regions totaling 34 bp were scattered throughout the whole genome.As has been observed in other lepidopteran species,12 of the 13 protein-coding genes (PCGs) were initiated by ATN codons,while the COI gene was tentatively designated by the CGA codon.A total of 11 PCGs harbored the complete termination codon TAA,while the COⅠ and COⅡ genes ended at a single T residue.All of the 22 tRNA genes showed typical clover structures except that the tRNAser(AGN) lacks the dihydrouridine (DHU) stem which is replaced by a simple loop.The intergenic spacer sequence between the tRNAser(AGN) and ND 1 also contained the ATACTAA motif,which is conserved in all other lepidopterans as well.Additionally,the 349 bp A+T-rich region was not comprised of large tandem repetitive sequences,but harbored a few structures common to other lepidopteran insects,such as the motif ATAGA followed by a 20 bp poly-T stretch,a microsatellite-like (AT)9 element preceded by the ATTTA motif,and a 5 bp poly-A site present immediately upstream of tRNAMet.The mitochondrial genomic sequence features found in this study not only contribute to genetic diversity information of the group,but also are useful in future studies of the endangered nymphalid butterfly in population genetic dynamics,species conservation,phylogeography and evolution.