The Deoptimization of Rabies Virus Matrix Protein Impacts Viral Transcription and Replication.

Jun Luo,Qiong Zhang,Yuting Wu,Xiaofeng Guo,Qin Tian,Mingzhu Mei,Meijun Mo,Boyue Zhang,Jing Zhao,Yue Zhang

doi:10.3390/v12010004

Abstract

Rabies virus (RABV) matrix (M) protein plays several important roles during RABV infection. Although previous studies have assessed the functions of M through gene rearrangements, this interferes with the position of other viral proteins. In this study, we attenuated M expression through deoptimizing its codon usage based on codon pair bias in RABV. This strategy more objectively clarifies the role of M during virus infection. Codon-deoptimized M inhibited RABV replication during the early stages of infection, but enhanced viral titers at later stages. Codon-deoptimized M also inhibited genome synthesis at early stage of infection and increased the RABV transcription rates. Attenuated M through codon deoptimization enhanced RABV glycoprotein expression following RABV infection in neuronal cells, but had no influence on the cell-to-cell spread of RABV. In addition, codon-deoptimized M virus induced higher levels of apoptosis compared to the parental RABV. These results indicate that codon-deoptimized M increases glycoprotein expression, providing a foundation for further investigation of the role of M during RABV infection.

Highlights

Rabies virus (RABV) causes a fatal neurological disease in both humans and animals
Codon-optimized and codon-deoptimized M genes were synthesized by GENEWIZ (Suzhou, China)
NA cells were infected with rHEP-G-Mmin or rHEP-G at an multiplicity of infection (MOI) of 0.01 or 3 and the expression of other viral proteins were assessed by Western blot analysis

Summary

Introduction

Rabies virus (RABV) causes a fatal neurological disease in both humans and animals. More than59,000 humans die of rabies each year, with the majority of cases occurring in developing countries.RABV is an unsegmented, negative-sense RNA virus belonging to the genus Lyssavirus of the familyRhabdoviridae. Rabies virus (RABV) causes a fatal neurological disease in both humans and animals. M is located at position 3 on the RABV genome from the 30 -leader sequence. Finke and colleagues demonstrated that the expression of M regulates RABV genome transcription and replication [3]. The overexpression of M increases the expression of HDAC6, which increases RABV transcription and replication through microtubule depolymerization [7]. The attenuation of M expression was performed through RABV rearrangements [3,9]. The rearrangement of M away from the 30 -leader sequence alters the location of other genes. Appropriate assays that alter M expression with no effects on the position of other RABV genes are required

Methods

Results

Conclusion