title: miR-21 promotes dengue virus serotype 2 replication in HepG2 cells.
abstract: Infection with the mosquito transmitted dengue virus (DENV) remains a significant worldwide public health problem. While the majority of infections are asymptomatic, infection can result in a range of symptoms. MicroRNAs (miRNAs) are small non-coding RNAs that regulate gene expression through repression or degradation of mRNAs. To understand the contribution of miRNAs to DENV 2 replication, we screened a number of candidate miRNAs for variations in expression levels during DENV 2 infection of HepG2 (liver) cells. Seven miRNAs were identified as differentially expressed, and one, miR-21, was differentially expressed at all time points examined. Interestingly, miR-21 was also differentially regulated in DENV 2 infection under conditions of antibody dependent enhancement of infection, and in direct Zika virus infection, but not in DENV 4 infection. The role of miR-21 during DENV infection was further examined by treating HepG2 cells with an anti-miR-21 (AMO-21) before DENV infection. The results showed a significant reduction in DENV 2 production, clearly suggesting that miR-21 plays a key role in DENV 2 replication. To further confirm the role of miR-21 in DENV infection, a peptide nucleic acid-21 (PNA-21) construct with a nucleotide sequence complementary to AMO-21, was co-administered with AMO-21 as an AMO-21/PNA-21 complex followed by DENV 2 infection. The results showed that AMO-21 significantly reduced DENV 2 titer, PNA-21 significantly increased DENV 2 titer and the combined AMO-21/PNA-21 showed no difference from non-treated infection controls. Taken together, the results show that miR-21 promotes DENV 2 replication, and this mechanism could serve as a possible therapeutic intervention point.
authors.affiliation: Department of Microbiology, Faculty of Science, Chulalongkorn University, Bangkok, 10330, Thailand.
authors.forename: Sitthichai
authors.initials: S
authors.lastname: Kanokudom
authors.affiliation: Organic Synthesis Research Unit, Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok, 10330 Thailand.
authors.forename: Tirayut
authors.initials: T
authors.lastname: Vilaivan
authors.affiliation: Institute of Molecular Biosciences, Mahidol University, Nakornpathom, 73170, Thailand.
authors.forename: Nitwara
authors.initials: N
authors.lastname: Wikan
authors.affiliation: Institute of Molecular Biosciences, Mahidol University, Nakornpathom, 73170, Thailand.
authors.forename: Chutima
authors.initials: C
authors.lastname: Thepparit
authors.affiliation: Institute of Molecular Biosciences, Mahidol University, Nakornpathom, 73170, Thailand.
authors.forename: Duncan R
authors.initials: DR
authors.lastname: Smith
authors.affiliation: Department of Microbiology, Faculty of Science, Chulalongkorn University, Bangkok, 10330, Thailand. Electronic address: wanchai.a@chula.ac.th.
authors.forename: Wanchai
authors.initials: W
authors.lastname: Assavalapsakul
mesh_terms: D000072283:A549 Cells; D000070416:Antagomirs / Q000494:pharmacology; D002352:Carrier Proteins; D004261:DNA Replication / Q000187:drug effects; D003715:Dengue / Q000821:virology; D003716:Dengue Virus / Q000187:drug effects* / Q000235:genetics; D005786:Gene Expression Regulation / Q000187:drug effects; D056945:Hep G2 Cells / Q000187:drug effects* / Q000821:virology*; D054884:Host-Pathogen Interactions; D006801:Humans; D053592:Interleukin-1 Receptor-Associated Kinases / Q000378:metabolism; D035683:MicroRNAs / Q000494:pharmacology*; D053594:Myeloid Differentiation Factor 88 / Q000378:metabolism; D020135:Peptide Nucleic Acids / Q000494:pharmacology; D065288:Serogroup; D020298:U937 Cells; D014779:Virus Replication / Q000187:drug effects*
chemical_list: D000070416:Antagomirs; D002352:Carrier Proteins; C524940:MIRN21 microRNA, human; C507779:MYD88 protein, human; D035683:MicroRNAs; D053594:Myeloid Differentiation Factor 88; D020135:Peptide Nucleic Acids; C507768:IRAK1 protein, human; D053592:Interleukin-1 Receptor-Associated Kinases
keywords: Anti-miRNA-21 oligonucleotide (AMO-21); Dengue virus serotype 2 (DENV 2); HepG2; MicroRNA (miRNA); Peptide nucleic acid-21 (PNA-21); miRNA-21 (miR-21)