title: Two NF-κB inhibitor-alpha (IκBα) genes from rock bream (Oplegnathus fasciatus): molecular characterization, genomic organization and mRNA expression analysis after immune stimulation.
abstract: IkBa is a member of IkB family, which sequesters NF-kB in an inactivate form in the cytoplasm and blocks the translocation of NF-kB to nucleus. The IkBa paralogs of rock bream (OfIkBa-A and OfIkBa-B) encoded IkBa proteins with typical features including, highly conserved IkB degradation motif, six ankyrin repeats and a PEST sequence. However, their amino acid identity and similarity were only 55.6 and 69.7%, respectively suggesting that these two genes could be the two different isoforms of IkBa. The number and size of the exons of OfIkBa-A and OfIkBa-B were conserved well with all the compared vertebrate species, although they have significantly different genomic sizes. Phylogenetic analysis revealed that OfIkBa-A and OfIkBa-B proteins cluster with IkBa family members; however, they were grouped with different subclades in IkBa family. Tissue specific expression of OfIkBa mRNA was constitutively detected in all the tested tissues, and they showed the higher transcription level in heart, liver, gill and peripheral blood cells, respectively. The injection of flagellin stimulated the mRNA expression of OfIkBa paralogs in head kidney and intestine. Moreover, the OfIkBa mRNA expression in gill and liver was significantly upregulated by LPS, poly I:C and Edwardsiella tarda challenges. The transcription of OfIkBa was up-regulated in early-phase of injection and then rapidly restored. These results suggest that the OfIkBa paralogs might be involved in rapid immune responsive reactions in rock bream against bacterial and viral pathogens.
authors.affiliation: Korea Institute of Ocean Science & Technology, Ansan 426-744, Republic of Korea.
authors.forename: Youngdeuk
authors.initials: Y
authors.lastname: Lee
authors.forename: Navaneethaiyer
authors.initials: N
authors.lastname: Umasuthan
authors.forename: Ilson
authors.initials: I
authors.lastname: Whang
authors.forename: Kasthuri Saranya
authors.initials: KS
authors.lastname: Revathy
authors.forename: Sukkyoung
authors.initials: S
authors.lastname: Lee
authors.forename: Mahanama
authors.initials: M
authors.lastname: De Zoysa
authors.forename: Chulhong
authors.initials: C
authors.lastname: Oh
authors.forename: Do-Hyung
authors.initials: DH
authors.lastname: Kang
authors.forename: Jae Koo
authors.initials: JK
authors.lastname: Noh
authors.forename: Jehee
authors.initials: J
authors.lastname: Lee
mesh_terms: D000818:Animals; D022202:Chromosomes, Artificial, Bacterial; D017931:DNA Primers / Q000235:genetics; D005408:Flagellin / Q000008:administration & dosage / Q000494:pharmacology; D040461:Gene Components / Q000235:genetics; D005786:Gene Expression Regulation / Q000187:drug effects / Q000276:immunology*; D016678:Genome / Q000235:genetics*; D051550:I-kappa B Kinase / Q000235:genetics* / Q000276:immunology; D008099:Liver / Q000378:metabolism; D009206:Myocardium / Q000378:metabolism; D010473:Perciformes / Q000235:genetics* / Q000276:immunology; D011487:Protein Conformation; D012333:RNA, Messenger / Q000187:drug effects / Q000378:metabolism*
chemical_list: D017931:DNA Primers; D012333:RNA, Messenger; D005408:Flagellin; D051550:I-kappa B Kinase