title: Expression pattern analysis of IRF4 and its related genes revealed the functional differentiation of IRF4 paralogues in teleost.
abstract: In mammals, interferon regulatory factor 4 (IRF4) plays an important role in the process of development and differentiation of B cells, T cells and dendritic cells. It can regulate immune pathway through IRF5, MyD88, IL21, PGC1α, and NOD2. In the present study, we investigated the expression pattern of IRF4 paralogues and these related genes for the first time in teleosts. The results showed that these genes were all expressed predominantly in known immune tissues while IRF5 was also relatively highly expressed in muscle. IRF4b, IL21, MyD88, IRF5 and NOD2 showed maternal expression in the oocyte and the higher expression of IRF4a, Mx and PGC1α before hatching might be involved in the embryonic innate defense system. Zebrafish embryonic fibroblast (ZF4) cells were infected with GCRV and SVCV. During GCRV infection, the expression of Mx was significantly up-regulated from 3 h to 24 h, reaching the highest level at 12 h (101.5-fold over the controls, P < 0.001). And the expression of IRF4a was significantly up-regulated from 3 h to 48 h, reaching the highest level at 12 h (13.75-fold over the controls, P < 0.001). While the expression of IRF4b was only slightly up-regulated at 12 h and 24 h (3.39-fold, 1.93-fold) above control levels, respectively. Whereas the expression of Mx was significantly up-regulated during SVCV infection from 1 h to 48 h, reaching the highest level at 24 h (11.49-fold over the controls, P < 0.001). IRF4a transcripts were significantly up-regulated from 6 h to 24 h, reaching the highest level at 24 h (41-fold over the controls, P < 0.01). IRF4b only showed a slightly up-regulation by SVCV at 24 h (3.2-fold over the controls, P < 0.01). IRF4a and IRF4b displayed a distinct tissue expression pattern, embryonic stages expression and inducible expression in vivo and in vitro, suggesting that IRF4 paralogues might play different roles in immune system.
authors.affiliation: School of Animal Science, Yangtze University, Jingzhou, 434020, China; State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei Province 430072, China.
authors.forename: Kete
authors.initials: K
authors.lastname: Ai
authors.affiliation: School of Animal Science, Yangtze University, Jingzhou, 434020, China.
authors.forename: Kai
authors.initials: K
authors.lastname: Luo
authors.affiliation: School of Animal Science, Yangtze University, Jingzhou, 434020, China.
authors.forename: Youshen
authors.initials: Y
authors.lastname: Li
authors.affiliation: School of Animal Science, Yangtze University, Jingzhou, 434020, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Hu
authors.affiliation: School of Animal Science, Yangtze University, Jingzhou, 434020, China.
authors.forename: Weihua
authors.initials: W
authors.lastname: Gao
authors.affiliation: School of Animal Science, Yangtze University, Jingzhou, 434020, China.
authors.forename: Liu
authors.initials: L
authors.lastname: Fang
authors.affiliation: School of Animal Science, Yangtze University, Jingzhou, 434020, China.
authors.forename: Guangming
authors.initials: G
authors.lastname: Tian
authors.affiliation: School of Animal Science, Yangtze University, Jingzhou, 434020, China.
authors.forename: Guoliang
authors.initials: G
authors.lastname: Ruan
authors.affiliation: School of Animal Science, Yangtze University, Jingzhou, 434020, China; State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei Province 430072, China. Electronic address: xuqiaoqing@163.com.
authors.forename: Qiaoqing
authors.initials: Q
authors.lastname: Xu
mesh_terms: D000818:Animals; D002460:Cell Line; D005393:Fish Diseases / Q000235:genetics / Q000276:immunology; D005786:Gene Expression Regulation; D007113:Immunity, Innate / Q000235:genetics*; D050835:Interferon Regulatory Factors / Q000235:genetics* / Q000378:metabolism; D010802:Phylogeny; D012087:Reoviridae / Q000502:physiology; D012088:Reoviridae Infections / Q000235:genetics / Q000276:immunology / Q000662:veterinary; D012209:Rhabdoviridae / Q000502:physiology; D018353:Rhabdoviridae Infections / Q000235:genetics / Q000276:immunology / Q000662:veterinary; D017422:Sequence Analysis, DNA; D015027:Zebrafish / Q000145:classification / Q000235:genetics* / Q000276:immunology*; D029961:Zebrafish Proteins / Q000235:genetics* / Q000378:metabolism; D000099218:Interferon Regulatory Factor-4
chemical_list: D050835:Interferon Regulatory Factors; D029961:Zebrafish Proteins; D000099218:Interferon Regulatory Factor-4; C000616513:IRF4a protein, zebrafish; C000616514:IRF4b protein, zebrafish
keywords: Expression; Interferon regulatory factor 4 (IRF4); Modulation; Paralogues