[Cloning and expression of Bmintegrin β1 in silkworm Bombyx mori]

Integrins are transmembrane glycoproteins, closely related to many physiological and pathological processes. In order to explore its role in silkworm, by PCR and Rapid-amplification of cDNA ends (RACE) technology, the full-length cDNA of Bmintegrin β1 in silkworm was acquired. The domain was predicted by domain prediction website. Phylogenetic tree was constructed to analyze its evolutionary relationship. By prokaryotic expression system, protein purification method and immunizing mouse, the antibody against Bmintegrin β1 recombinant protein was obtained. The spatial-temporal expression profile of Bmintegrin β1 was investigated by semi quantitative PCR and Western blotting. Then we identified all 3 different spliceosomes, and they shared a common open reading frame of 2 502 bp, encoding 833 amino acids. Bmintegrin β1 contained all the classic domains of the integrin family, such as Integrin-B-tail, transmembrane domain etc. Phylogenetic analysis indicated that Bmintegrin β1 was close to the homologous proteins from Heliothis assulta and Danaus plexippus. In order to understand the function of Bmintegrin β1 further, we generated the antibody. In addition, Western blotting demonstrated that the antibody recognized the Bmintegrin β1 recombinant protein. Then, semi quantitative PCR and Western blotting results showed that Bmintegrin β1 was widely expressed in most of tissues, among of them, it's exhibited the highest expression level in hemacyte. Overall, this study provides a foundation for the study of silkworm integrin family.