PPP2R5D promotes hepatitis C virus infection by binding to viral NS5B and enhancing viral RNA replication

© 2022. The Author(s)..

BACKGROUND: Hepatitis C virus (HCV) infection increased the risk of hepatocellular carcinoma. Identification of host factors required for HCV infection will help to unveil the HCV pathogenesis. Adaptive mutations that enable the replication of HCV infectious clones could provide hints that the mutation-carrying viral protein may specifically interact with some cellular factors essential for the HCV life cycle. Previously, we identified D559G mutation in HCV NS5B (RNA dependent RNA polymerase) important for replication of different genotype clones. Here, we searched for the factors that potentially interacted with NS5B and investigated its roles in HCV infection.

METHODS: Wild-type-NS5B and D559G-NS5B of HCV genotype 2a clone, J6cc, were ectopically expressed in hepatoma Huh7.5 cells, and NS5B-binding proteins were pulled down and identified by mass spectrometry. The necessity and mode of action of the selected cellular protein for HCV infection were explored by experiments including gene knockout or knockdown, complementation, co-immunoprecipitation (Co-IP), colocalization, virus infection and replication, and enzymatic activity, etc. RESULTS: Mass spectrometry identified a number of cellular proteins, of which protein phosphatase 2 regulatory subunit B'delta (PPP2R5D, the PP2A regulatory B subunit) was one of D559G-NS5B-pulled down proteins and selected for further investigation. Co-IP confirmed that PPP2R5D specifically interacted with HCV NS5B but not HCV Core and NS3 proteins, and D559G slightly enhanced the interaction. NS5B also colocalized with PPP2R5D in the endoplasmic reticulum. Knockdown and knockout of PPP2R5D decreased and abrogated HCV infection in Huh7.5 cells, respectively, while transient and stable expression of PPP2R5D in PPP2R5D-knockout cells restored HCV infection to a level close to that in wild-type Huh7.5 cells. Replicon assay revealed that PPP2R5D promoted HCV replication, but the phosphatase activity and catalytic subunit of PP2A were not affected by NS5B.

CONCLUSIONS: PPP2R5D interactes with HCV NS5B and is required for HCV infection in cultured hepatoma cells through facilitating HCV replication.

Medienart:

E-Artikel

Erscheinungsjahr:

2022

Erschienen:

2022

Enthalten in:

Zur Gesamtaufnahme - volume:19

Enthalten in:

Virology journal - 19(2022), 1 vom: 14. Juli, Seite 118

Sprache:

Englisch

Beteiligte Personen:

Anwar, Muhammad Ikram [VerfasserIn]
Li, Ni [VerfasserIn]
Zhou, Qing [VerfasserIn]
Chen, Mingxiao [VerfasserIn]
Hu, Chengguang [VerfasserIn]
Wu, Tao [VerfasserIn]
Chen, Haihang [VerfasserIn]
Li, Yi-Ping [VerfasserIn]
Zhou, Yuanping [VerfasserIn]

Links:

Volltext

Themen:

EC 3.1.3.16
Hepatitis C virus
Journal Article
PPP2R5D
PPP2R5D protein, human
Phosphatase activity
Protein–protein interaction
Protein Phosphatase 2
RNA, Viral
RNA dependent RNA polymerase
Research Support, Non-U.S. Gov't
Viral Nonstructural Proteins

Anmerkungen:

Date Completed 18.07.2022

Date Revised 01.08.2022

published: Electronic

Citation Status MEDLINE

doi:

10.1186/s12985-022-01848-5

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM343565889