Real-time Imaging of Rabies Virus Entry into Living Vero cells.

Haijiao Xu,Xian Hao,Junguang Jiang,Hongda Wang,Mingjun Cai,Shaowen Wang,Qiwei Qin,Zhiyong Wang,Maolin Zhang

doi:10.1038/srep11753

Abstract

Understanding the mechanism of rabies virus (RABV) infection is vital for prevention and therapy of virulent rabies. However, the infection mechanism remains largely uncharacterized due to the limited methods and viral models. Herein, we utilized a powerful single-virus tracking technique to dynamically and globally visualize the infection process of the live attenuated rabies vaccine strain-SRV9 in living Vero cells. Firstly, it was found that the actin-enriched filopodia is in favor of virus reaching to the cell body. Furthermore, by carrying out drug perturbation experiments, we confirmed that RABV internalization into Vero cells proceeds via classical dynamin-dependent clathrin-mediated endocytosis with requirement for intact actin, but caveolae-dependent endocytosis is not involved. Then, our real-time imaging results unambiguously uncover the characteristics of viral internalization and cellular transport dynamics. In addition, our results directly and quantitatively reveal that the intracellular motility of internalized RABV particles is largely microtubule-dependent. Collectively, our work is crucial for understanding the initial steps of RABV infection, and elucidating the mechanisms of post-infection. Significantly, the results provide profound insight into development of novel and effective antiviral targets.

Highlights

Been reported to exploit the microtubules as transport tracks, such as adenovirus, herpes simplex virus, HIV, and influenza virus[10,15,22,23]
These previous experimental methods were mainly based on electron microscopy (EM), which cannot disclose the dynamic process of viral infection with the disadvantage to only acquire static images
The SRV9 belongs to living attenuated rabies vaccine strain with good safety and immunogenicity, resulting from the alteration of Arg→ Ser in the 333 position of glycoprotein of rabies viruses[31]

Summary

Introduction

Been reported to exploit the microtubules as transport tracks, such as adenovirus, herpes simplex virus, HIV, and influenza virus[10,15,22,23]. The live attenuated rabies vaccine strain-SRV9 was used as the novel viral model to investigate the infection mechanism of RABV. We applied live-cell fluorescence imaging to investigate the process of viral entry.

Results

Conclusion