New and highly efficient expression systems for expressing selectively foreign protein in the silk glands of transgenic silkworm

• Published in: Transgenic research 2010-02, Vol.19 (1), p.29-44
• Main Authors: Zhao, Aichun, Zhao, Tianfu, Zhang, Yuansong, Xia, Qingyou, Lu, Cheng, Zhou, Zeyang, Xiang, Zhonghuai, Nakagaki, M.
• Format: Article
• Language: English
• Subjects: Animal Genetics and Genomics; Animals; Animals, Genetically Modified; Biological and medical sciences; Biomedical and Life Sciences; Biomedical Engineering/Biotechnology; Biotechnology; Bombyx - genetics; Bombyx - metabolism; Bombyx mori; Cloning, Molecular; Efficiency; Exocrine Glands - metabolism; Exocrine Glands - secretion; Fibroins - genetics; Fibroins - metabolism; Fibroins - secretion; Fundamental and applied biological sciences. Psychology; Gene Expression Regulation; Gene Transfer Techniques; Genetic Engineering; Genetic technics; Green Fluorescent Proteins - genetics; Green Fluorescent Proteins - metabolism; Green Fluorescent Proteins - secretion; Introns; Life Sciences; Methods. Procedures. Technologies; Models, Biological; Molecular Medicine; Organ Specificity - genetics; Original Paper; Plant Genetics and Genomics; Plasmids - chemical synthesis; Plasmids - genetics; Recombinant Fusion Proteins - genetics; Recombinant Fusion Proteins - metabolism; Recombinant Fusion Proteins - secretion; Secretion; Silk; Silk - metabolism; Silk gland; Transcription; Transgenes - genetics; Transgenic animals and transgenic plants; Transgenics
• ISSN: 0962-8819; 1573-9368
• DOI: 10.1007/s11248-009-9295-7

We constructed three different fibroin H-chain expression systems to estimate the efficacy of producing recombinant proteins in the cocoon of transgenic silkworms. The results showed that the three different EGFP/H-chain fusion genes were all expressed selectively in the posterior silk gland of the transgenic silkworm. The recombinant protein content of transgenic silkworm cocoons is up to 15% (w/w) when using the most highly efficient H-chain expression system. To our knowledge, in comparison with silkworm silk gland expression systems in the literature, the highly efficient expression system developed in this study is the most efficient silkworm silk gland expression system to date. This expression system is the best candidate for foreign gene production and for creation of novel functional silk material. The results suggested the N-terminal domain and the intron of the H-chain gene are important in the secretion of fibroin and its transcription, respectively.