4种昆虫基因组中的线粒体假基因

Nuclear mitochondrial pseudogenes in four sequenced insect genomes

为了进一步了解昆虫核基因组中线粒体假基因(Numts)序列分布情况,避免Numts序列对基于线粒体DNA(mtDNA)进行系统发育关系研究结果的误导,利用Blast N对GenBank中已完成核基因组和mtDNA测序的4种昆虫核基因组中的Numts序列进行检索,结果表明:冈比亚按蚊Anopheles gambiae中没有Numts序列;黑腹果蝇Drosophila melanogaster中仅有少量Numts序列;赤拟谷盗Tribolium cast-aneum和意大利蜜蜂Apis mellifera基因组中Numts序列超过100条,尤其是意大利蜜蜂中的Numts序列涵盖全部mtDNA.ND2,ND4,ND5,COⅠ与lrRNA向核内转移频率高于其他mtDNA基因片段,因此,在使用其进行系统发育关系研究时需加倍谨慎.

The aim of this study was to have further information about the distribution of nuclear mito- chondrial pseudogenes （Numts） in insect genomes, and to avoid misguidance of Numts sequences in the molecular phylogeny based on mtDNA. Sequences alignment （NCBI-Blast N） was carried out with mito- chondrial and corresponding nuclear genome sequences in 4 insect species. The results showed： copy num- ber ranges from none in the African malaria mosquito Anopheles gambiae, few copies in the fruit fly Dro- sophila rnelanogaster, to more than 100 in the flour beetle Tribolium castaneum and the honeybee Apis mellifera, especially in A. mellifera, Numts spanned the whole mtDNA. The reconstructed frequency of ND2, ND4, NDS, CO I and lrRNA integrations into the nucleus were higher than other mitochondrial genes. So, it needed for doubly cautious when using it for the study of phylogenetic relationships.