Introduction of Recombinant GnRH, Transmembrane Domain of PEA and Hyperthermophilic Archaea Histone (GPH) as a Novel Carrier for Gene Transfer

We successfully constructed and expressed a generic recombinant protein named GPH via gene engineering. GPH is made up of gonadotropin releasing hormone (GnRH), a transmembrane area of Pseudomonas aeruginosa exotoxin A (PEAII) and hyperthermophilic archaea histone (HPhA). After expression and purification, the engineered GPH protein was detected by SDS-PAGE. We then examined its transfection ability using the plasmid, pEGFP-C1 (green fluorescent plasmid). Electrophoretic mobility shift assays showed that recombinant GPH slowed down the migration rate of pEGFP-C1 in agarose gels, confirming that GPH had combined with the plasmid. Transfection experiments showed that GPH can carry pEGFP-C1 into HeLa cells to produce fluorescence. Also, genomic DNA extraction from transfected cells and PCR examination showed that recombinant GPH mediated the transport of pEGFP-C1 into HeLa cells. Immunohistochemical analysis detected GPH in transfected cells. Enzyme-linked immune sorbent assays detected GPH bound to GnRHR on the surface of HeLa cells. Taken together, recombinant GPH has the ability to bind to and transport DNA into target cells. Thus, GPH is a potential gene delivery vehicle in gene therapy.