Molecular Cloning and Expression of the Fusion (F) Gene from Newcastle Disease virus in <i>Escherichia coli</i>: A Platform for Further Studies.

Newcastle disease (ND) is a highly contagious viral disease affecting most avian species. The fusion protein in the ND virus serves as the target for immune response. The goal of this study was to develop the DNA vaccine using a fusion gene from the Newcastle virus. A new candidate DNA vaccine against Newcastle disease virus (NDV) has been developed. This innovative vaccine uses a fusion gene that encodes immunogenic proteins derived from NDV. The hypothesis behind this approach is that the fusion gene induces a strong immune response against the virus, potentially leading to long-term immunity in vaccinated individuals. Fusion gene RNA was extracted from the Newcastle virus and amplified by the reverse transcription-polymerase chain reaction (RT-PCR). Afterwards, it was sub-cloned in the pTG-19T vector, then into the expression vector pET43.1a E. coli BL21. Gene expression was induced by IPTG. The fusion protein was subjected to Sodium dodecyl-sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Sequencing and PCR results confirmed the successful cloning of the fusion gene into the vector. Digestion results showed the target gene had been successfully inserted in the pET43.1a plasmid. SDS-PAGE revealed a protein band of about 54.7 kDa. Analysis of the constructs in E. coli cells demonstrated successful expression of gene inserts in vitro. Our results indicate that the fusion protein produced by pET43.1a in E. coli can be used as a DNA vaccine. However, a weak band of expressed protein was observed, indicating that the fusion protein produced by pET43.1a in E. coli was not highly efficient. This survey encourages further research to test the produced protein as a vaccine in vivo and in vitro.