Expression of a Fusion Protein Consisting of Cholera Toxin B Subunit and an Anti-Diabetic Peptide (p277) from Human Heat Shock Protein in Transgenic Tobacco Plants

摘要

A DNA construct encoding cholera toxin B subunit (CTB) and an anti-diabetic peptide from human heat shock protein 60 (hsp60) as a fusion protein was produced and transferred into low-nicotine tobacco through Agmbacterium-mediated transformation. Integration of the fusion gene into the plant genome was confirmed by PCR. The transcriptional expression of the fusion gene was demonstrated by RT-PCR. Western blot analysis further verified the synthesis and assembly of the fusion protein into pentamers intransgenic tobacco. G_(Ml)-ELISA showed that the plant-derived fusion protein retained G_(Ml)-ganglioside receptor binding specificity. The fusion protein accounted approximately for 0.1% of the total leaf protein. The production of transgenic plants expressing CTB-p277 offers an opportunity to test plant tissues for oral peptide antigen therapy against autoimmune diabetes by inducing oral tolerance.