PMID- 37272842 OWN - NLM STAT- MEDLINE DCOM- 20230712 LR - 20231206 IS - 1098-5514 (Electronic) IS - 0022-538X (Print) IS - 0022-538X (Linking) VI - 97 IP - 6 DP - 2023 Jun 29 TI - Hepatitis C Virus Disrupts Annexin 5-Mediated Occludin Integrity through Downregulation of Protein Kinase Calpha (PKCalpha) and PKCeta Expression, Thereby Promoting Viral Propagation. PG - e0065523 LID - 10.1128/jvi.00655-23 [doi] LID - e00655-23 AB - Annexins (ANXs) comprise a family of calcium- and phospholipid-binding proteins and are implicated in the hepatitis C virus (HCV) life cycle. Here, we demonstrate a novel role of ANX5 in the HCV life cycle. Comparative analysis by quantitative PCR in human hepatoma cells revealed that ANX2, ANX4, and ANX5 were highly expressed among the ANX family proteins. Knockdown of ANX5 mRNA resulted in marked enhancement of HCV RNA replication but had no effect on either HCV translation or assembly. Using the HCV pseudoparticle (HCVpp) system, we observed enhancement of HCVpp infectivity in ANX5 knockdown Huh-7OK1 cells, suggesting that ANX5 is involved in suppression of HCV entry. Additionally, we observed that subcellular localizations of tight-junction proteins, such as claudin 1 (CLDN1) and occludin (OCLN), were disrupted in the ANX5 knockdown cells. It was reported that HCV infection was facilitated by disruption of OCLN distribution and that proper distribution of OCLN was regulated by its phosphorylation. Knockdown of ANX5 resulted in a decrease of OCLN phosphorylation, thereby disrupting OCLN distribution and HCV infection. Further analysis revealed that protein kinase C (PKC) isoforms, including PKCalpha and PKCeta, play important roles in the regulation of ANX5-mediated phosphorylation and distribution of OCLN and in the restriction of HCV infection. HCV infection reduced OCLN phosphorylation through the downregulation of PKCalpha and PKCeta expression. Taken together, these results suggest that ANX5, PKCalpha, and PKCeta contribute to restriction of HCV infection by regulating OCLN integrity. We propose a model that HCV disrupts ANX5-mediated OCLN integrity through downregulation of PKCalpha and PKCeta expression, thereby promoting HCV propagation. IMPORTANCE Host cells have evolved host defense machinery to restrict viral infection. However, viruses have evolved counteracting strategies to achieve their infection. In the present study, we obtained results suggesting that ANX5 and PKC isoforms, including PKCalpha and PKCeta, contribute to suppression of HCV infection by regulating the integrity of OCLN. The disruption of OCLN integrity increased HCV infection. We also found that HCV disrupts ANX5-mediated OCLN integrity through downregulation of PKCalpha and PKCeta expression, thereby promoting viral infection. We propose that HCV disrupts ANX5-mediated OCLN integrity to establish a persistent infection. The disruption of tight-junction assembly may play important roles in the progression of HCV-related liver diseases. FAU - Abe, Takayuki AU - Abe T AD - Division of Infectious Disease Control, Center for Infectious Diseases, Kobe University Graduate School of Medicine, Kobe, Japan. FAU - Marutani, Yuki AU - Marutani Y AD - Division of Infectious Disease Control, Center for Infectious Diseases, Kobe University Graduate School of Medicine, Kobe, Japan. FAU - Deng, Lin AU - Deng L AD - Division of Infectious Disease Control, Center for Infectious Diseases, Kobe University Graduate School of Medicine, Kobe, Japan. FAU - Matsui, Chieko AU - Matsui C AD - Division of Infectious Disease Control, Center for Infectious Diseases, Kobe University Graduate School of Medicine, Kobe, Japan. FAU - Fukasawa, Masayoshi AU - Fukasawa M AD - Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, Tokyo, Japan. FAU - Suzuki, Ryosuke AU - Suzuki R AD - Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan. FAU - Wakita, Takaji AU - Wakita T AD - Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan. FAU - Matsuura, Yoshiharu AU - Matsuura Y AD - Center for Infectious Diseases Education and Research (CiDER), Osaka University, Osaka, Japan. AD - Laboratory of Virus Control, Research Institute for Microbial Diseases (RIMD), Osaka University, Osaka, Japan. FAU - Shoji, Ikuo AU - Shoji I AUID- ORCID: 0000-0002-0730-4379 AD - Division of Infectious Disease Control, Center for Infectious Diseases, Kobe University Graduate School of Medicine, Kobe, Japan. LA - eng PT - Journal Article PT - Research Support, Non-U.S. Gov't DEP - 20230605 PL - United States TA - J Virol JT - Journal of virology JID - 0113724 RN - 0 (Annexin A5) RN - 0 (Occludin) RN - 0 (OCLN protein, human) RN - 0 (Protein Isoforms) RN - EC 2.7.1.- (protein kinase C eta) RN - EC 2.7.11.13 (Protein Kinase C-alpha) RN - 0 (ANXA5 protein, human) SB - IM MH - Humans MH - *Annexin A5/genetics/metabolism MH - Down-Regulation MH - *Hepacivirus/physiology MH - *Hepatitis C MH - *Occludin/genetics/metabolism MH - Protein Isoforms/genetics MH - Protein Kinase C-alpha/genetics/metabolism MH - Virus Internalization PMC - PMC10308894 OTO - NOTNLM OT - annexin 5 OT - hepatitis C virus OT - occludin OT - protein kinase C OT - tight junction COIS- The authors declare no conflict of interest. EDAT- 2023/06/05 13:04 MHDA- 2023/07/03 06:41 PMCR- 2023/12/05 CRDT- 2023/06/05 10:13 PHST- 2023/07/03 06:41 [medline] PHST- 2023/06/05 13:04 [pubmed] PHST- 2023/06/05 10:13 [entrez] PHST- 2023/12/05 00:00 [pmc-release] AID - 00655-23 [pii] AID - jvi.00655-23 [pii] AID - 10.1128/jvi.00655-23 [doi] PST - ppublish SO - J Virol. 2023 Jun 29;97(6):e0065523. doi: 10.1128/jvi.00655-23. Epub 2023 Jun 5.