• International Journal of Industrial Entomology and Biomaterials
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• v.6 no.1
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• pp.49-55
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• 2003

We describe the generation of transgenic silkworm that carrying the chimeric fibroin light chain (L-chain) gene. Previously, we have cloned the complete fibroin L-chain gene from the silkworm Baekok-Jam, Bombyx mori, and the complete fibroin gene from the oak silkworm, Antheraea yamamai. The 444 bp repetitive sequence of A. yamamai fibroin gene was inserted into the exon 6 of B. mori fibroin L-chain gene to produce chimeric fibroin L-chain gene. The chimeric fibroin L-chain gene was cloned into the polyhedrin gene site of Autographa californica nuclear polyhedrosis virus (AcNPV) to yield a recombinant baculovirus as a fibroin gene targeting vector, One-day-old fifth instar female silkworm larvae were injected with the recombinant baculovirus and then mated with normal male moths. Genomic DNA from their progenies was extracted and screened for the desired targeting event by using PCR and Southern blot analysis. The analysis showed that the chimeric fibroin gene had intergrated into the L-chain gene on the genome by homologous recombination and was transmitted through generations. The transgenic silkworm carrying the chimeric fibroin gene were approximately 43.2% in $F_2$ generation, and the silkworms synthesized the fusion protein in cocoons layer.

• Applied Biological Chemistry
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• v.38 no.6
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• pp.485-489
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• 1995

The medium additives such as fatty acid, lipid, mannose, folic acid, $CaCl_2$ were examined to enhance recombinant ${\beta}-galactosidase\;({\beta}-gal)$ production in T-flask and air-lift bioreactor. The addition of each component. such as cholesterol, tocopherol, tricaprylin, mannose and folic acid at AcNPV infection of Tn5B1-4 cells enhanced ${\beta}-gal$ production, whereas the addition of $CaCl_2$ did not increase ${\beta}-gal$ production. The recombinant ${\beta}-gal$ production using the infection medium supplemented with a mixture of 0.34 mM cholesterol, 2.2 mM mannose and 0.045 M folic acid was enhanced 2 fold in an air-lift bioreactor, compared to the basal medium.