Molecular Phylogenetics of Silkworm (Bombyx mori) Based on Mariner-Like Elements (MLEs)

Mariner-Like Elements (MLEs)를 이용한 누에의 분자적 계통 분석

In order to understand molecular phylogenetics of silkworm (Bombyx mori), we analyzed the sequences of BmoMAR isolated from Bomhyx mori that is partial coding gene of transposase of mariner-like element(MLE). By pairwise comparing nucleotide sequences of BmoMAR with ten previously reported insect MLEs accessed in GeneBank, the average genetic distance was estimated to be 0.4840. The phylogenetics tree constructed from nine insect species except for human MLE(Hsmarl) by UPGMA method indicated that MLEs are divided into three clusters, and Drosophila mariutiana was independently subgrouped. Bombyx mori(BmoMAR) was subgrouped with microcaddishfly (Orthotrichia cristata), webworm(Atteva punctella), almond moth(Ephestia cautella), Hyalopora cecropia which we lepidoptera. Phylogenetics tree according to UPGMA principle, on the basis of informative nucleotide sequences of nine insect MLEs, indicated that Bombyx mori was more closely related to microcaddishfly(Orthotrichia cristata) and webworm (Atteva punctella) of lepidoptera. We suggest that insect MLEs are a useful key for studying molecular phylogenetics among intra species of insects.

본 연구는 누에(Bombyx mori)에서 cloning한 BomMAR의 염기서열을 기초로 하여 곤충 MLE(mariner-like ele-ment)의 계통분석을 통한 누에의 분자적 계통 관계를 이해하고자 수행하였다. 전체 10 종의 MLE중에서 15%의 낮은 상동성을 보이는 인간 MLE(Hsmarl)을 제외한 9종의 MLE의 DNA 염기서열을 이용한 UPGMA 분석 결과, BmoMAR을 포함한 10종의 MLE가 세 가지의 subfamily 로 grouping되는 것을 알 수 있었으며, 누에는 genetic distance 0.4332에서 같은 lepidoptera(나비목) 의 H. cecropia, almond moth, webworm 및 microcaddisfly와 함께 grouping 되었다. 따라서 이와 같은 결과는 MLE가 곤충의 계통분석에 유용한 molecular tool이 될 수 있음을 보여준다.