Synthetic construct of Homo sapiens clone IFNB1 gene encoding complete protein in prokaryotes.

Introduction: Interferons are antiviral and anti-proliferative cytokines that are made and secreted by vertebrate cells. Interferon beta can regulate immune responses and is used as the main medicine in many diseases, including multiple sclerosis.Goals: At the global level, the expression of recombinant protein IFNB is considered as a standard method for medicinal and therapeutic usage in human. In this research, we tried to apply a simple and low-cost process for protein production.Materials and Methods: In this study, the INFB1-b was amplified by polymerase chain reaction (PCR), and sub-cloned in prokaryotic expression vector PET32a. E.coli BL21(DE3) was transformed with PET32a/IFNB1-b and gene expression was induced by IPTG. Afterwards, cells analyzed by 12% SDS-PAGE. Recombinant IFNB1-b was expressed in this system with 6xhis tag at C-terminus and thioredoxin tag at N-terminus. The expressed protein was purified by affinity-chromatography using (Ni-NTA) resin.Results: PCR and sequencing results confirmed the successful cloning of the target gene into the vector. SDS-PAGE analysis showed the high level expression of IFNB1b protein and high concentration of the recombinant protein was obtained via the purification process by affinity-chromatography. This gene has later been registered in GenBank with the accession number of MF678818.Conclusion: The expression of IFNB1b was low when cloned under the T7 promoter without any fusion tags. In this study, in order to increase the solubility of the recombinant protein, we fused the IFNB1b gene to thioredoxin and 6xhis tag. In this research the yield of recombinant IFNB1b protein was increased significantly by 840ug/ml.

Keywords:

PCR , Recombinant protein , interferon beta gene , Eschershia coli.