title: Characterisation of arginase paralogues in salmonids and their modulation by immune stimulation/ infection.
abstract: In this study we show that four arginase isoforms (arg1a, arg1b, arg2a, arg2b) exist in rainbow trout (Oncorhynchus mykiss) and Atlantic salmon (Salmo salar). We have characterised these molecules in terms of a) sequence analysis, b) constitutive expression in different tissues, and modulated expression following c) stimulation of head kidney macrophages in vitro, or d) vaccination/infection with Yersinia ruckeri and e) parasite infection (AGD caused by Paramoeba perurans and PKD caused by Tetracapsuloides bryosalmonae). Synteny analysis suggested that these arginase genes are paralogues likely from the Ss4R duplication event, and amino acid identity/similarity analyses showed that the proteins are relatively well conserved across species. In rainbow trout constitutive expression of one or both paralogues was seen in most tissues but different constitutive expression patterns were observed for the different isoforms. Stimulation of rainbow trout head kidney macrophages with PAMPs and cytokines also revealed isoform specific responses and kinetics, with arg1a being particularly highly modulated by the PAMPs and pro-inflammatory cytokines. In contrast the type II arginase paralogues were induced by rIl-4/13, albeit to a lesser degree. Vaccination and infection with Y. ruckeri also revealed isoform specific responses, with variation in tissue expression level and kinetics. Lastly, the impact of parasite infection was studied, where down regulation of arg1a and arg1b was seen in two different models (AGD in salmon and PKD in trout) and of arg2a in AGD. The differential responses seen are discussed in the context of markers of type II responses in fish and paralogue subfunctionalization.
authors.affiliation: Scottish Fish Immunology Research Centre, Institute of Biological and Environmental Sciences, University of Aberdeen, Tillydrone Avenue, Aberdeen AB24 2TZ, UK; Marine Scotland Science Marine Laboratory, 375 Victoria Rd, Aberdeen AB11 9DB, UK. Electronic address: r01ob13@abdn.ac.uk.
authors.forename: Ottavia
authors.initials: O
authors.lastname: Benedicenti
authors.affiliation: Scottish Fish Immunology Research Centre, Institute of Biological and Environmental Sciences, University of Aberdeen, Tillydrone Avenue, Aberdeen AB24 2TZ, UK.
authors.forename: Tiehui
authors.initials: T
authors.lastname: Wang
authors.affiliation: Scottish Fish Immunology Research Centre, Institute of Biological and Environmental Sciences, University of Aberdeen, Tillydrone Avenue, Aberdeen AB24 2TZ, UK.
authors.forename: Eakapol
authors.initials: E
authors.lastname: Wangkahart
authors.affiliation: Scottish Fish Immunology Research Centre, Institute of Biological and Environmental Sciences, University of Aberdeen, Tillydrone Avenue, Aberdeen AB24 2TZ, UK.
authors.forename: Douglas J
authors.initials: DJ
authors.lastname: Milne
authors.affiliation: Scottish Fish Immunology Research Centre, Institute of Biological and Environmental Sciences, University of Aberdeen, Tillydrone Avenue, Aberdeen AB24 2TZ, UK.
authors.forename: Jason W
authors.initials: JW
authors.lastname: Holland
authors.affiliation: Marine Scotland Science Marine Laboratory, 375 Victoria Rd, Aberdeen AB11 9DB, UK.
authors.forename: Catherine
authors.initials: C
authors.lastname: Collins
authors.affiliation: Scottish Fish Immunology Research Centre, Institute of Biological and Environmental Sciences, University of Aberdeen, Tillydrone Avenue, Aberdeen AB24 2TZ, UK. Electronic address: c.secombes@abdn.ac.uk.
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Secombes
mesh_terms: D000818:Animals; D001119:Arginase / Q000235:genetics* / Q000378:metabolism; D005393:Fish Diseases / Q000235:genetics* / Q000276:immunology / Q000382:microbiology; D029941:Fish Proteins / Q000235:genetics* / Q000378:metabolism; D015870:Gene Expression; D060226:Head Kidney / Q000276:immunology / Q000378:metabolism; D007527:Isoenzymes / Q000235:genetics / Q000378:metabolism; D008264:Macrophages / Q000276:immunology / Q000378:metabolism; D017686:Oncorhynchus mykiss; D009928:Organ Specificity; D020317:Salmo salar; D017422:Sequence Analysis, DNA; D014611:Vaccination / Q000662:veterinary; D015009:Yersinia Infections / Q000235:genetics / Q000276:immunology / Q000382:microbiology / Q000662:veterinary*; D044124:Yersinia ruckeri / Q000502:physiology
chemical_list: D029941:Fish Proteins; D007527:Isoenzymes; D001119:Arginase
keywords: Arginase paralogues; Macrophages; Oncorhynchus mykiss; Parasite infections; Salmo salar; Vaccination