Cloning and Expression of the Gene Encoding Antigenic Regions of 3D Non-Structural Protein of Foot-and-Mouth Disease Virus

Foot and Mouth Disease (FMD) is a highly contagious and devastating disease that spreads rapidly and causes many economic damages. One of the important      methods for detection of FMD and particularly differentiation of vaccinated from infected animals, is the use of non-structural proteins as antigens in ELISA kits. The purpose of this study was cloning of the gene sequence and expression of the antigenic regions of 3D nonstructural protein as one of the diagnostic options. For amplification of the antigenic regions of FMD virus 3D protein, specific primers containing NdeI and EcoRI restriction sites were designed and the polymerase chain reaction was performed. The sequences cut by these two enzymes, were inserted into PET21a+ vectors. The recombinant plasmids were then transformed into E. coli (DH5α). Colony-PCR tests and enzymatic digestions were performed on the resulting colonies and the presence of the target gene was confirmed. The gene sequence was further confirmed after sequencing. For production of recombinant antigens, the recombinant vector was transferred to the expression host of E. coli-BL21. The bacteria containing the recombinant gene were induced with IPTG and the expression of the recombinant protein was confirmed using the SDS-PAGE method. The molecular weight of the recombinant protein was about 24 kDa, and it can be used in the design of ELISA diagnostic kit.