Construction of Mini-genome System for both Rabies virus Laboratory Strain and Field Epidemic Strain

Abstract

Rabies virus (RABV) causes a zoonotic disease known as rabies that affects humans and mammals. With a genome length of 12 kb, RABV is classified as a non-segmented, negative-stranded RNA virus that encodes five different structural proteins. The nucleoprotein (N), phosphoprotein (P), and large RNA polymerase protein (L) forms ribonucleoprotein (RNP); together with the viral genome it serves as a transcription and replication template of the viral genome. This research aims to construct a mini- genome system for the RABV laboratory strain CVS and the field epidemic strain 5989 to study its viral replication and transcription mechanism. The result of luciferase-based assay showed that CVS strain has an optimum ratio for mini-genome of 0.16 ng MG : 0.16 ng N : 0.04 ng P : 0.12 ng L as reflected on the high luciferase activity (1.74 x 107 RLU/sec). While, two possible mini-genome ratios were found for 5989 strain including 0.16 ng MG : 0.16 ng N : 0.04 ng P : 0.08 ng L or 0.16 ng MG : 0.16 ng N : 0.04 ng P : 0.12 ng L; however, no statistically significant differences was observed between the two ratios. Though improvements still need to be applied for future studies, it can be concluded that the mini- genome system was able to represent the genome replication and transcription activity of both RABV strains through luciferase activity, which can be a stepping stone in developing therapeutic drugs or vaccines.