Construction and expression of RNase-resistant virus-like particles containing N gene of MERS-CoV RNA

Objective To construct and express ribonuclease-resistant virus-like particles containing the RNA fragmengts of MERS-CoV N gene. Methods The coat protein and maturase gene of E. coli bacteriophage MS2 was amplified by PCR, then the gene was cloned into pET32a to construct the intermediate vector pET32MS.The gene fragments harboring MERS-CoV N gene and beta-actin was cloned into the downstream of pET32MS to construct the prokaryotic expression vector p32MS-EMC-Beta.The recombinant plasmid p32MS-EMC-Beta was transformed into E. coli BL21(DE) competent cells and induced with IPTG. The virus-like particles were obtained after purification. RNase digestion test and stability test were carried out to observe the stability of the particles. Results The RNase-resistant virus- like particles which was able to express the gene fragments containing MERS-CoV N gene and beta-actin were successfully produced and were shown to be stored stable for 30 days at 37℃. Conclusion The virus- like particles with high safety and stability can be used as positive standards and quality controls in the application of MERS-CoV detection. Key words: Bacteriophage MS2; Coronavirus; Virus-like particles; Expressed sequence tags