Consideration of the evolutional history of wild silk moth Bombyx mandarinaby comparing the pattern of mariner-like-element among some specimens now inhabiting in different Asian area

Abstract

PCR against genomic DNA from individuals of Bombyx mandarina distributed in three areas of east Asia, i.e., Japan, Korea and China, was performed with the inverted terminal repeats of the Hyalophora cecropia MLE as a primer. Each specimen gave several bands with different sizes. One individual from China had a discrete 4.2-kb band containing a BMC1 retrotransposon, which is a unique fragment detected in almost all of the silkworm races and strains. Thus, the 4.2-kb unit might provide a clue for addressing the issue about the segregation of B. mori genome. From the phylogenetic analysis, MLE (BmTNML ) of 4.2kb band and 2.5kb band from the specimen of Fukuoka had high similarity each other supporting the idea that this type of MLE is an ancient type before segregation of B. mandarina among different chromosome numbers, i.e.,27 and 28.