title: Induction of genes encoding NADPH oxidase components and activation of IFN regulatory factor-1 by prolactin in fish macrophages.
abstract: The role played by prolactin (PRL) in fish immunity is scant. We report here that stimulation of the Atlantic salmon monocytic cell line SHK-1 with native salmon PRL resulted in activation of the respiratory burst and induction of the expression of the genes encoding the phagocyte NADPH oxidase components p47phox, p67phox and gp91phox, and the transcription factor IFN regulatory factor-1 (IRF-1). Interestingly, the pharmacologic inhibition of the Jak/Stat signaling pathway with AG490 blocked reactive oxygen species (ROS) production, and the induction of genes encoding the NADPH oxidase components and IRF-1 in PRL-activated SHK-1 cells. In addition, PRL promoted the phosphorylation of Stat and induced the DNA binding activity of IRF-1. These results, together with the presence of several consensus target motifs for Stat and IRF-1 in the promoter of the tilapia p47phox gene, suggest that PRL regulates p47phox gene expression in fish through the activation of these two key transcription factors. Taken together, our results demonstrate that PRL induces the expression of the genes encoding the major phagocyte NADPH oxidase components and ROS production in fish macrophages via the JAK2/Stat/IRF-1 signaling pathway.
authors.affiliation: 1Department of Biochemistry and Microbiology, Faculty of Science, Universidad Austral de Chile, Campus Isla Teja, Valdivia, Chile.
authors.forename: Víctor H
authors.initials: VH
authors.lastname: Olavarría
authors.forename: Jaime E
authors.initials: JE
authors.lastname: Figueroa
authors.forename: Victoriano
authors.initials: V
authors.lastname: Mulero
mesh_terms: D000818:Animals; D002460:Cell Line; D029941:Fish Proteins / Q000276:immunology*; D005786:Gene Expression Regulation / Q000187:drug effects; D050856:Interferon Regulatory Factor-1 / Q000235:genetics / Q000378:metabolism; D053612:Janus Kinases / Q000378:metabolism; D009000:Monocytes / Q000187:drug effects / Q000276:immunology*; D019255:NADPH Oxidases / Q000235:genetics / Q000378:metabolism*; D059372:Nucleotide Motifs / Q000235:genetics; D011388:Prolactin / Q000276:immunology*; D017382:Reactive Oxygen Species / Q000378:metabolism; D050791:STAT Transcription Factors / Q000378:metabolism; D020317:Salmo salar; D015398:Signal Transduction / Q000187:drug effects; D017210:Tilapia; D015533:Transcriptional Activation; D020032:Tyrphostins / Q000494:pharmacology
chemical_list: D029941:Fish Proteins; D050856:Interferon Regulatory Factor-1; D017382:Reactive Oxygen Species; D050791:STAT Transcription Factors; D020032:Tyrphostins; C095512:alpha-cyano-(3,4-dihydroxy)-N-benzylcinnamide; D011388:Prolactin; D019255:NADPH Oxidases; C060505:neutrophil cytosolic factor 1; D053612:Janus Kinases
keywords: Reactive oxygen species; cell signaling; evolution; inflammation; respiratory burst; salmon; teleosts