Cloning And Prokaryotic Expression Of The Bombyx Mori Bmrbp1 Gene, Related To The Sex Determination

Bombyx mori is not only an important economic insect, but also one of the model organisms for classical genetics research. Many researches shown that male is better than the female in such characteristics as the resistibility,health, ratio of the leave-silk transformation. Rearing-male-only can bring about 15% increase in the silk production without an increase in cost, moreover, the silk produced by male is better in quality than the female, therefore, research the sex determination mechanism in the Bombyx mori ,and finally rearch the goal of the rearing-male-only will effectively improve the productivity and economic efficiency of the sericulture. Meanwhile Lepidoptera order insect is the main agricultural pest, and Bombyx mori is the representant of this order, clarify the sex determination mechanism in Bombyx mori, and hold it as a model.will benefit the research work of agricultural pest preventation.The classical genetics research shown a strong female determinator(fem) presented on the W chromosome controls the sex development of the Bombyx mori, while ,by far the putative fem gene has not been identified. The homologue of the Drosophila dsx gene lying in the terminal of the sex determination cascade was found in the Bombyx mori. Similar to the dsx, the Bmdsx transcript is alternatively spliced in male and female to produce male and female specific mature mRNA, which code for male-specific(BMDSXM) and female-specific(BMDSX) proteins to control the terminal sex differentiation in Bombyx mori. While the alternative splicing mechanism of the the Bmdsx pre-mRNA is very different from that of the dsx. The default splicing form of dsx is male specific, in female, the tra/tra-2 activate the female-specific splicing form. While in Bombyx mori,the default splicing form is female specific, an inhibitor repressed the splicing of the female-specific extrons in the male.In Drosophila, rbp1 is an important splicing factor involved in the female-specific splicing,the Bombyx mori homologue of Bmrbp1 was researched in our work.The main research contents and results are as follows:(1)cloned the Bombyx mori homologue of the the Bmrbp1 gene based on the silkworm EST...