title: Hepatitis B virus-specific miRNAs and Argonaute2 play a role in the viral life cycle.
abstract: Disease-specific serum miRNA profiles may serve as biomarkers and might reveal potential new avenues for therapy. An HBV-specific serum miRNA profile associated with HBV surface antigen (HBsAg) particles has recently been reported, and AGO2 and miRNAs have been shown to be stably associated with HBsAg in serum. We identified HBV-associated serum miRNAs using the Toray 3D array system in 10 healthy controls and 10 patients with chronic hepatitis B virus (HBV) infection. 19 selected miRNAs were then measured by quantitative RT-PCR in 248 chronic HBV patients and 22 healthy controls. MiRNA expression in serum versus liver tissue was also compared using biopsy samples. To examine the role of AGO2 during the HBV life cycle, we analyzed intracellular co-localization of AGO2 and HBV core (HBcAg) and surface (HBsAg) antigens using immunocytochemistry and proximity ligation assays in stably transfected HepG2 cells. The effect of AGO2 ablation on viral replication was assessed using siRNA. Several miRNAs, including miR-122, miR-22, and miR-99a, were up-regulated at least 1.5 fold (P<2E-08) in serum of HBV-infected patients. AGO2 and HBcAg were found to physically interact and co-localize in the ER and other subcellular compartments. HBs was also found to co-localize with AGO2 and was detected in multiple subcellular compartments. Conversely, HBx localized non-specifically in the nucleus and cytoplasm, and no interaction between AGO2 and HBx was detected. SiRNA ablation of AGO2 suppressed production of HBV DNA and HBs antigen in the supernatant.
  
  
  CONCLUSIONS
  These results suggest that AGO2 and HBV-specific miRNAs might play a role in the HBV life cycle.
authors.affiliation: Department of Gastroenterology and Metabolism, Applied Life Sciences, Institute of Biomedical & Health Sciences, Hiroshima University, Hiroshima, Japan.
authors.forename: C Nelson
authors.initials: CN
authors.lastname: Hayes
authors.forename: Sakura
authors.initials: S
authors.lastname: Akamatsu
authors.forename: Masataka
authors.initials: M
authors.lastname: Tsuge
authors.forename: Daiki
authors.initials: D
authors.lastname: Miki
authors.forename: Rie
authors.initials: R
authors.lastname: Akiyama
authors.forename: Hiromi
authors.initials: H
authors.lastname: Abe
authors.forename: Hidenori
authors.initials: H
authors.lastname: Ochi
authors.forename: Nobuhiko
authors.initials: N
authors.lastname: Hiraga
authors.forename: Michio
authors.initials: M
authors.lastname: Imamura
authors.forename: Shoichi
authors.initials: S
authors.lastname: Takahashi
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Aikata
authors.forename: Tomokazu
authors.initials: T
authors.lastname: Kawaoka
authors.forename: Yoshiiku
authors.initials: Y
authors.lastname: Kawakami
authors.forename: Waka
authors.initials: W
authors.lastname: Ohishi
authors.forename: Kazuaki
authors.initials: K
authors.lastname: Chayama
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D060565:Argonaute Proteins / Q000235:genetics / Q000378:metabolism*; D016022:Case-Control Studies; D002460:Cell Line; D005260:Female; D020869:Gene Expression Profiling; D006509:Hepatitis B / Q000235:genetics* / Q000378:metabolism*; D006512:Hepatitis B Core Antigens / Q000378:metabolism; D006514:Hepatitis B Surface Antigens / Q000097:blood / Q000378:metabolism; D006515:Hepatitis B virus / Q000502:physiology*; D006801:Humans; D008297:Male; D035683:MicroRNAs / Q000097:blood / Q000235:genetics* / Q000378:metabolism; D008875:Middle Aged; D008969:Molecular Sequence Data; D011485:Protein Binding; D034622:RNA Interference; D015398:Signal Transduction; D014779:Virus Replication; D055815:Young Adult
chemical_list: C466422:AGO2 protein, human; D060565:Argonaute Proteins; D006512:Hepatitis B Core Antigens; D006514:Hepatitis B Surface Antigens; D035683:MicroRNAs