title: Soluble interleukin-1 receptor, a potential negative regulator of orange-spotted grouper Epinephelus coioides interleukin-1 system.
abstract: In this study, the cDNA sequence encoding interleukin-1 (Il-1) receptor-like protein of orange-spotted grouper Epinephelus coioides was obtained. The newly identified sequence was named soluble type I Il-1 receptor (sIl-1rI) owing to its structural composition, which had two Ig-like domains, lack of transmembrane region and the Toll/interleukin-1 receptor (TIR) domain, similar to the brown rat Rattus norvegicus soluble Il-1rI. In addition, sequence comparison and phylogenetic analysis indicated that E. coioides sequence had a closer relationship with Il-1rI than Il-1rII. Real-time PCR revealed that sil-1rI mRNA expression presented a process of decrease, restoration and increase in Cryptocaryon irritans-infected E. coioides. The negative correlation between Il-1β and sil-1rI mRNA in C. irritans-infected head-kidney implied the potential negative regulatory role of sil-1rI in E. coioides Il-1 system. The leucocytes incubated with lipopolysaccharide or polyriboinosinic polyribocytidylic acid exhibited different expression profiles of sil-1rI. Recombinant Il-1β (rIl-1β) protein was capable of inducing sil-1rI mRNA under the concentration of 100 ng ml(-1) , suggesting that high dosage or excess Il-1β would stimulate the expression of sil-1rI to maintain the homoeostasis of E. coioides Il-1 system. For the first time, the role of teleost Il-1rI in parasite infection has been identified, and soluble Il-1r was found in fish.
authors.affiliation: State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals and Guangdong Provincial Key Laboratory for Aquatic Economic Animals, College of Life Sciences, Sun Yat-Sen (Zhongshan) University, Guangzhou 510275, PR China.
authors.forename: D Q
authors.initials: DQ
authors.lastname: Lu
authors.forename: M
authors.initials: M
authors.lastname: Yao
authors.forename: S B
authors.initials: SB
authors.lastname: Yi
authors.forename: Y W
authors.initials: YW
authors.lastname: Li
authors.forename: X C
authors.initials: XC
authors.lastname: Liu
authors.forename: Y
authors.initials: Y
authors.lastname: Zhang
authors.forename: H R
authors.initials: HR
authors.lastname: Lin
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D016770:Ciliophora Infections / Q000276:immunology / Q000662:veterinary; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D060226:Head Kidney / Q000166:cytology / Q000469:parasitology; D007375:Interleukin-1 / Q000276:immunology*; D053583:Interleukin-1beta / Q000494:pharmacology; D007962:Leukocytes / Q000276:immunology; D008070:Lipopolysaccharides / Q000494:pharmacology; D008969:Molecular Sequence Data; D010473:Perciformes / Q000235:genetics / Q000276:immunology* / Q000469:parasitology; D010802:Phylogeny; D011070:Poly I-C / Q000494:pharmacology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D017472:Receptors, Interleukin-1 / Q000235:genetics / Q000276:immunology*; D011994:Recombinant Proteins / Q000494:pharmacology; D013154:Spleen / Q000166:cytology; D059467:Transcriptome
chemical_list: D018076:DNA, Complementary; D007375:Interleukin-1; D053583:Interleukin-1beta; D008070:Lipopolysaccharides; D012333:RNA, Messenger; D017472:Receptors, Interleukin-1; D011994:Recombinant Proteins; D011070:Poly I-C
keywords: Cryptocaryon irritans; expression profile; mitogen; recombinant Il-1β; tissue distribution