title: Molecular characterization, expression, and functional analysis of two thioredoxins in the black rockfish (Sebastes schlegelii).
abstract: Thioredoxins (TRxs) are a family of small evolutionarily conserved proteins that are essential for the maintenance of cellular homeostasis. Two TRx homologue cDNAs were isolated from a black rockfish concanavalin A (Con A)/phorbol myristate acetate (PMA)-stimulated leucocyte cDNA library and named BrTPx1-1 and BrTPx1-2. As compared with other known TRx peptide sequences, the most conserved regions of both BrTRx1-1 and BrTRx1-2 peptides were found to be the redox-active site Trp-Cys-X-X-Cys (WCXXC). The TRx present in most species is a TRx1-2 protein with a Cys-Pro-Gly-Cys (CPGC) active site. However, in the larger 13 kDa BrTRx1-1 protein, a Cys-Pro-Pro-Cys (CPPC) active site was identified. Here, we report the identification of a new member of the TRx protein family from the teleost black rockfish, which defines a new subclass of 13-kDa TRx1-1 proteins. Phylogenetic analysis indicated that both BrTRx1-1 and BrTRx1-2 were grouped with other vertebrate TRx1 peptides. BrTRx1-1 expression was strongly induced in peripheral blood leucocytes (PBLs) 12-24 h following Con A/PMA stimulation, with peak expression at 24 h post-stimulation. BrTRx1-2 was induced in PBLs after stimulation with lipopolysaccharide (LPS), Con A/PMA, or poly I:C at 24 h. The BrTRx1-1 gene was predominantly expressed in the liver and gills, while BrTRx1-2 was expressed in PBLs and gills. After treatment with a high concentration (10 μg/mL) of rBrTRx1-1 or rBrTRx1-2, kidney leucocytes exhibited increased cell proliferation and viability under oxidative stress.
authors.affiliation: Department of Marine Biology & Aquaculture, Institute of Marine Industry, College of Marine, Science, Gyeongsang National University, Tongyeong, Republic of Korea.
authors.forename: Chan-Il
authors.initials: CI
authors.lastname: Park
authors.forename: Jee-Hyun
authors.initials: JH
authors.lastname: Jung
authors.forename: Won Joon
authors.initials: WJ
authors.lastname: Shim
authors.forename: Ju-Won
authors.initials: JW
authors.lastname: Kim
authors.forename: Eun-Gyeong
authors.initials: EG
authors.lastname: Kim
authors.forename: Ji-Min
authors.initials: JM
authors.lastname: Jeong
authors.forename: Do-Hyung
authors.initials: DH
authors.lastname: Kim
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics / Q000302:isolation & purification; D004926:Escherichia coli / Q000235:genetics; D029941:Fish Proteins / Q000235:genetics* / Q000276:immunology / Q000378:metabolism*; D005399:Fishes / Q000235:genetics* / Q000378:metabolism*; D020869:Gene Expression Profiling; D007668:Kidney / Q000276:immunology / Q000378:metabolism; D007962:Leukocytes / Q000276:immunology / Q000378:metabolism; D008099:Liver / Q000276:immunology / Q000378:metabolism; D008934:Mitogens / Q000378:metabolism; D008969:Molecular Sequence Data; D010802:Phylogeny; D012333:RNA, Messenger / Q000235:genetics; D011994:Recombinant Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016415:Sequence Alignment; D013879:Thioredoxins / Q000737:chemistry / Q000235:genetics* / Q000276:immunology / Q000378:metabolism*; D014018:Tissue Distribution
chemical_list: D018076:DNA, Complementary; D029941:Fish Proteins; D008934:Mitogens; D012333:RNA, Messenger; D011994:Recombinant Proteins; D013879:Thioredoxins