Heat shock protein (HSP90) affects the replication of rotavirus

Abstract

Aim: To explore the effects of HSP90 on rotavirus (RV) replication. Materials & methods: The interaction between NSP2 and HSP90 was analyzed by immunoprecipitation assay, and co-localization confirmed by an immunofluorescence assay. The viral titer was measured by immunofluorescence assay and viral protein expression investigated by western blotting. Results: The interaction between NSP2 and HSP90 was confirmed. Knockdown of HSP90 using siRNA resulted in a decrease in NSP2 expression and virus titer. HSP90 inhibitor 17-AAG significantly decreased NSP2 and NSP5 expression, as well as the virus titer, while proteasome inhibitor MG132 restored the protein amount and the viral titer. Conclusion: HSP90 is involved in rotavirus replication, and inhibition of HSP90 promotes the degradation of NSP2 through the proteasome pathway.

Plain language summary

Rotavirus is a type of virus that causes severe diarrhea, especially in children. The virus infects the cell in our bodies. These cells have proteins which carry out important functions and can help the growth of the virus. One of these proteins, called HSP90, interacts with a protein of the virus, called NSP2. After infection, these proteins move to the same place within the cell. Decreasing the level of HSP90 also decreases the level of NSP2, slowing the growth of the virus. Understanding how HSP90 and NSP2 work will help to develop new drugs to treat rotavirus infection.

Article highlights

Background

• Heat shock protein 90 (HSP90) appears to play an essential role in viral replication, but little is known regarding the role of HSP90 in rotavirus (RV) infection.

Methods

• RV laboratory strain SA11 was used in this study.

• Virus titers were measured by Fluorescent formation units assay and viral protein expression checked by WB.

• The interaction of HSP90 and NSP2 was confirmed by immunoprecipitation (IP) and confocal laser microscope.

• siRNA used to knockdown the expression of HSP90 and HSP90 activity was inhibited.

Results

• The HSP90 inhibition resulted in decreased RV replication.

• Knockdown of HSP90 by siRNA decreased RV protein levels and virus replication.

• HSP90 interacted with virus protein NSP2.

• Inhibition of the proteasome pathway decreased viral protein degradation.

Conclusion

• HSP90 was used by RV to facilitate virus replication by chaperoning viral proteins and preventing their degradation via the proteasome.

Keywords: :

• 17-AAG
• HSP90
• NSP2
• proteasome pathway
• RV

Acknowledgments

We thank T Kobayashi (Laboratory of Viral Replication, Research Institute for Microbial Diseases Research Center for Infectious Diseases, Osaka University, Osaka, Japan) for providing the SA-11 strain. We thank Liwen Bianji (Edanz) (www.liwenbianji.cn) for editing the language of a draft of this manuscript.

Author contributions

YG Li conceived and supervised all projects. SM Hu and XL Tao conceptualized the study and edited and revised the manuscript. W Zhao, LK Luo, RL Li, ZP Ma and LY Sun participated in the acquisition of data and the experimentation. All authors read and approved the final version of the manuscript.

Financial disclosure

This work was supported by the Science and Technology Program of Liaoning Province (Grant No. 2022-BS-320; 2021-MS-334) and Liaoning Education Department of China (Grant No. LJKMZ20221242). The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

Competing interests disclosure

The authors have no competing interests or relevant affiliations with any organization or entity with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Writing disclosure

No writing assistance was utilized in the production of this manuscript.

Additional information

Funding

This work was supported by the Science and Technology Program of Liaoning Province (Grant No. 2022-BS-320; 2021-MS-334) and Liaoning Education Department of China (Grant No. LJKMZ20221242).