Construction And Application Of Gene Targeting Vector Using Fibroin Light Chain As Homogenous Fragment

The larva of silkworm has a pair of highly developed silk glands with the ability to synthesize fibroin, and it is potential for bioplant. Two homogenouns fragment {[E5(89bp) I5 (1060bp) E6(30bp)] and [E7(406)以及3'-flank(98bp) ]sequences } were acquired from fibrion light chain gene by PCR amplification. The left and the right homogennouns sequences were respectively detected and analysised.It shows that the two sequences have highly homology with the Bombyx mori fibrion light chain gene which has published on the GenBank. A gene vector was constructed using the two homogenouns fragment,hMCSF controlled by fibrion heavey chain gene promoter, and GFP controlled by A3 promotor. This vector was induced into Bombyx mori silk gland, BmN cell, GFP was detected, and the vector devoted experiences for further research.A DNA fragment of 975bp sequence (GenBank accession No: EU352872), which may be a mariner-like elements associated sequence, was acquired form Bombyx mori genomic DNA by PCR amplification. Blast search showed that there is 90% homology between 52-449nt regions of this sequence and Bombyx mandarina mariner-like elements DNA, its homologous sequence was also found in the 5th intron of acetylcholinesterase gene, microsatellite S1104-R sequence, downstream sequence of stop codon of BmBRC-NZ3 mRNA and intron of ErB.1 gene. It was implied that the mariner-like elements associated sequence was transposed time after time in the Bombyx mori genomic DNA, and was diverged in different regions of genomic DNA during evolutional process.