title: Two variants of selenium-dependent glutathione peroxidase from the disk abalone Haliotis discus discus: Molecular characterization and immune responses to bacterial and viral stresses.
abstract: Glutathione peroxidase (GPx) is an essential member of the antioxidant systems of living organisms and may be involved in immune defense against pathogenic invasion. In the current study, two selenium-dependent glutathione peroxidases (AbSeGPxs) that shared 54.3% identity were identified from the disk abalone Haliotis discus discus. The open reading frames (ORFs) of AbSeGPx-a and AbSeGPx-b coded for 222 and 220 amino acids, respectively, with a characteristic selenocysteine residue encoded by an opal stop codon (TGA). The conserved selenocysteine insertion sequence (SECIS) element was predicted in the 3' untranslated region (UTR) of both isoforms, and they were found to form two stem-loop structures. Amino acid comparison and phylogenetic studies revealed that the AbSeGPxs were closely related to those in other mollusk species and were evolutionarily distinct from those of other taxonomic groups. The SYBR Green qPCR was employed in investigating the transcripts of AbSeGPxs. The expression of AbSeGPxs mRNA was examined in different embryonic developmental stages and differential expression patterns for AbSeGPx-a and AbSeGPx-b were noted. Meanwhile, the highest expression of AbSeGPxs was detected in the hepatopancreas of healthy adult animals. Next, transcriptional levels were profiled in hemocytes of adults to determine the immune responses of AbSeGPxs to microbial infections. The results revealed the significant up-regulation of AbSeGPx-a in a time-dependent manner after bacterial (Listeria monocytogenes and Vibrio parahaemolyticus) and viral (viral hemorrhagic septicemia virus) infections. Consequently, these findings indicate that AbSeGPx-a and AbSeGPx-b might be involved in the embryonic development of disk abalone and the regulation of immune defense system of adult animals.
authors.affiliation: Department of Marine Life Sciences, School of Marine Biomedical Sciences, Jeju National University, Jeju Self-Governing Province 690-756, Republic of Korea; Fish Vaccine Research Center, Jeju National University, Jeju Special Self-Governing Province 690-756, Republic of Korea.
authors.forename: S D N K
authors.initials: SD
authors.lastname: Bathige
authors.affiliation: Department of Marine Life Sciences, School of Marine Biomedical Sciences, Jeju National University, Jeju Self-Governing Province 690-756, Republic of Korea; Fish Vaccine Research Center, Jeju National University, Jeju Special Self-Governing Province 690-756, Republic of Korea.
authors.forename: Navaneethaiyer
authors.initials: N
authors.lastname: Umasuthan
authors.affiliation: Department of Marine Life Sciences, School of Marine Biomedical Sciences, Jeju National University, Jeju Self-Governing Province 690-756, Republic of Korea; Fish Vaccine Research Center, Jeju National University, Jeju Special Self-Governing Province 690-756, Republic of Korea.
authors.forename: G I
authors.initials: GI
authors.lastname: Godahewa
authors.affiliation: Department of Marine Life Sciences, School of Marine Biomedical Sciences, Jeju National University, Jeju Self-Governing Province 690-756, Republic of Korea; Fish Vaccine Research Center, Jeju National University, Jeju Special Self-Governing Province 690-756, Republic of Korea.
authors.forename: William Shanthakumar
authors.initials: WS
authors.lastname: Thulasitha
authors.affiliation: Fish Vaccine Research Center, Jeju National University, Jeju Special Self-Governing Province 690-756, Republic of Korea.
authors.forename: Ilson
authors.initials: I
authors.lastname: Whang
authors.affiliation: Ocean and Fisheries Research Institute, Jeju Special Self-Governing Province 699-915, Republic of Korea.
authors.forename: Seung Hwan
authors.initials: SH
authors.lastname: Won
authors.affiliation: Informatics Development & Management Group, Korea Institute of Oriental Medicine, 1672 Yuseongdae-ro, Yuseong-gu, Daejeon, 305-811, Republic of Korea.
authors.forename: Chul
authors.initials: C
authors.lastname: Kim
authors.affiliation: Department of Marine Life Sciences, School of Marine Biomedical Sciences, Jeju National University, Jeju Self-Governing Province 690-756, Republic of Korea; Fish Vaccine Research Center, Jeju National University, Jeju Special Self-Governing Province 690-756, Republic of Korea. Electronic address: jehee@jejunu.ac.kr.
authors.forename: Jehee
authors.initials: J
authors.lastname: Lee
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D018076:DNA, Complementary / Q000235:genetics; D041981:Gastrointestinal Tract / Q000378:metabolism; D049851:Gastropoda / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D014644:Genetic Variation; D005880:Gills / Q000378:metabolism; D005979:Glutathione Peroxidase / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D006066:Gonads / Q000378:metabolism; D006434:Hemocytes / Q000276:immunology; D006458:Hemolymph / Q000378:metabolism; D043143:Hepatopancreas / Q000378:metabolism; D008088:Listeriosis / Q000276:immunology / Q000662:veterinary; D008969:Molecular Sequence Data; D009132:Muscles / Q000378:metabolism; D029141:Novirhabdovirus; D012333:RNA, Messenger / Q000378:metabolism; D018353:Rhabdoviridae Infections / Q000276:immunology / Q000662:veterinary; D014735:Vibrio Infections / Q000276:immunology / Q000662:veterinary; D014736:Vibrio parahaemolyticus
chemical_list: D018076:DNA, Complementary; D012333:RNA, Messenger; D005979:Glutathione Peroxidase
keywords: AbSeGPx-a; AbSeGPx-b; Haliotis discus discus; Immune response; Selenium-dependent glutathione peroxidase (SeGPx)