Influenza Virus-Induced Novel miRNAs Regulate the STAT Pathway

Abstract

MicroRNAs (miRNAs) are essential regulators of gene expression in humans and can control pathogenesis and host–virus interactions. Notably, the role of specific host miRNAs during influenza virus infections are still ill-defined. The central goal of this study was to identify novel miRNAs and their target genes in response to influenza virus infections in airway epithelium. Human airway epithelial cells exposed to influenza A virus (IAV) induced several novel miRNAs that were identified using next-generation sequencing (NGS) and their target genes by biochemical methods. NGS analysis predicted forty-two RNA sequences as possible miRNAs based on computational algorithms. The expression patterns of these putative miRNAs were further confirmed using RT-PCR in human bronchial epithelial cells exposed to H1N1, H9N1(1P10), and H9N1 (1WF10) strains of influenza virus. A time-course study showed significant downregulation of put-miR-34 in H1N1 and put-miR-35 in H9N1(1P10)-infected cells, which is consistent with the NGS data. Additionally, put-miR-34 and put-miR-35 showed a high fold enrichment in an argonaute-immunoprecipitation assay compared to the controls, indicating their ability to form a complex with argonaute protein and RNA-induced silencing complex (RISC), which is a typical mode of action found with miRNAs. Our earlier studies have shown that the replication and survival of influenza virus is modulated by certain transcription factors such as NF-ĸB. To identify the target(s) of these putative miRNAs, we screened 84 transcription factors that have a role in viral pathogenesis. Cells transfected with mimic of the put-miR-34 showed a significant decrease in the expression of Signal Transducers and Activators of Transcription 3 (STAT3), whereas the inhibitor of put-miR-34 showed a significant increase in STAT3 expression and its phosphorylation. In addition, put-miR-34 had 76% homology to the untranslated region of STAT3. NGS and PCR array data submitted to the Gene Ontology project also predicted the role of transcription factors modulated by put-miR-34. Our data suggest that put-miR-34 may be a good target for antiviral therapy.

Human rhinovirus 16 infection modifies the microRNA landscape during epithelial cell infection

“…This idea of miRNA’s being biomarkers has gained traction in recent years [10] and has recently gained further popularity with IAV infection [37]. In our work we found that increased expression of either of these two miRNAs correlated with a possible promotion of viral infection (Figure 5) at the expense of the immune response.…”

“…From this we identified a panel of 9 miRNAs demonstrating differential expression over our time course with a panel being initially upregulated and then downregulated by 18 hours, another panel continually increasing in expression over time and a final panel being up and then downregulated or vice versa. This pattern of miRNA expression could be representative of a dynamic interaction between the virus and host with both positive and negative impacts for viral replication and a protective immune response as has been shown in other infections [35-37] and in our initial analysis using the KEGG database. Previous studies assessing the impact of RV on miRNA expression have identified limited miRNA’s that could be important for ongoing infection such as miR-155 and miR-128 [15-16].…”

MicroRNA hsa-miR-203a-3p promotes H1N1 and NDV Virus Replication by suppressing the IFNA signaling

“…When infected by a virus, these cells initiate a dual response by releasing both IFN-I and IFN-III, a process that relies on the activation of RIG-I/MAVS pathway (47).Virus employies different strategies to escape the host's immune system like cytokine escape, antigenic change, antigen presentation and evasion of natural killer cells (48,49). It has recently been established in research articlers that the pathogenic insult is also associated with the cellular miRNA expression, and altered miRNA expression leads to the miRNA-mediated silencing of host and viral transcripts (50)(51)(52).…”

Interferon‐mediated repression of miR ‐324‐5p potentiates necroptosis to facilitate antiviral defense

“…Eliminating pathogen‐infected cells by necroptosis is a critical mechanism of host defense against pathogen infection (Wang et al , 2014 ). MiRNAs play important roles in controlling the response to pathogen infection by regulating the expression of target genes (Othumpangat et al , 2021 ; Zhang et al , 2021 ). Our study revealed that miR‐324‐5p functions as a suppressor of necroptosis by directly inhibiting MLKL expression and that induction of IFNs by pathogens such as IAV downregulates the expression of miR‐324‐5p through the JAK/STAT1 signaling pathway (Fig 8 ).…”