IRF9-Stat2 Fusion Protein as an Innate Immune Inducer to Activate Mx and Interferon-Stimulated Gene Expression in Zebrafish Larvae

Chang Jen Huang, Chih Ming Chou, Huang Wei Lien, Cheng Ying Chu, Jhih Yun Ho, Yimin Wu, Chia Hsiung Cheng

Research output: Contribution to journalArticle

2 Citations (Scopus)


Virus infection often causes large amounts of mortality during teleost larvae stage. Strong induction of innate immunity to increase survival rates of teleost larvae has been less reported. In this study, we present a zebrafish IRF9-Stat2 fusion protein (zIRF9-S2C) as a strong innate immunity inducer and characterized induction of interferon-stimulated genes (ISGs) in zebrafish larvae. zIRF9-S2C could mimic IFN-stimulated gene factor 3 (ISGF3) complex to constitutively activate transcription of Mx promoter through IFN-stimulatory element (ISRE) sites. Mutation of two ISRE sites on Mx promoter reduced transactivation activities of Mx promoter induced by zIRF9-S2C. An electrophoretic mobility shift assay experiment shows that zIRF9-S2C could directly bind to two ISRE sites of Mx promoter. Induction of transactivation of Mx promoter by zIRF9-S2C shows significantly higher activity than by zebrafish IFN1 (zIFN1), IFNγ (zIFNγ), and Tetraodon IRF9-S2C (TnIRF9-S2C). zIRF9-S2C raises transcription of Mxa, Mxb, Mxc, Ifnφ1, Ifnφ2, and Ifnφ3 in zebrafish liver ((ZFL) cell line) cells and zebrafish larvae. Collectively, we suggest that IRF9-S2C could activate transcription of ISGs with species-specific recognition and could be an innate immunity inducer in teleost larvae.

Original languageEnglish
Pages (from-to)1-10
Number of pages10
JournalMarine Biotechnology
Publication statusAccepted/In press - May 12 2017



  • Innate immunity
  • IRF9
  • ISG
  • Mx
  • Stat2

ASJC Scopus subject areas

  • Biotechnology
  • Aquatic Science

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