title: Molecular cloning and characterization of Toll-like receptor 9 in Japanese flounder, Paralichthys olivaceus.
abstract: Toll-like receptor (TLR) 9 cDNA and gene were cloned from Japanese flounder, Paralichthys olivaceus. The Japanese flounder TLR9 cDNA encodes 1065 amino acids. The leucine-rich domain (LRD) and the Toll/interleukin-1 receptor (TIR) domain found in other vertebrate TLR9s were conserved in Japanese flounder TLR9. The gene is composed of three exons and two introns. The Japanese flounder tumor necrosis factor (TNF) gene promoter was activated in Japanese flounder TLR9-transformed hirame natural embryo (HINAE) cells upon stimulation with synthesized CpG oligodeoxynucleotide (ODN), but not by stimulation with GpC ODN. The Japanese flounder TLR9 gene was highly expressed in epithelial and lymphoid organs, such as the gills, intestines, kidney, spleen and stomach in an apparently healthy fish. The mRNA copy numbers of Japanese flounder TLR9 and its adapter protein, the myeloid differentiation factor 88 (MYD88) were increased in some organs including blood, gill, kidney and spleen after Edwardsiella tarda challenge. Immunohistochemical analysis revealed that TLR9 and MYD88 were expressed in the same cells of kidney. Few TLR9-expressing cells were found in gill, kidney and spleen in healthy Japanese flounder, but many were found in these organs after E. tarda challenge and were coincident with lesions that had been colonized by the bacteria.
authors.affiliation: Laboratory of Genome Science, Graduate School of Marine Science and Technology, Tokyo University of Marine Science and Technology, Konan 4-5-7, Minato, Tokyo 108-8477, Japan.
authors.forename: Tomokazu
authors.initials: T
authors.lastname: Takano
authors.forename: Hidehiro
authors.initials: H
authors.lastname: Kondo
authors.forename: Ikuo
authors.initials: I
authors.lastname: Hirono
authors.forename: Makoto
authors.initials: M
authors.lastname: Endo
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Saito-Taki
authors.forename: Takashi
authors.initials: T
authors.lastname: Aoki
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002478:Cells, Cultured; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D020609:Edwardsiella tarda / Q000276:immunology; D004756:Enterobacteriaceae Infections / Q000235:genetics / Q000276:immunology / Q000662:veterinary; D005393:Fish Diseases / Q000235:genetics / Q000276:immunology; D005432:Flounder / Q000196:embryology / Q000235:genetics* / Q000276:immunology; D005786:Gene Expression Regulation / Q000502:physiology*; D008969:Molecular Sequence Data; D053594:Myeloid Differentiation Factor 88 / Q000235:genetics / Q000276:immunology; D009928:Organ Specificity / Q000502:physiology; D017434:Protein Structure, Tertiary / Q000235:genetics; D051217:Toll-Like Receptor 9 / Q000235:genetics* / Q000276:immunology; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics / Q000276:immunology
chemical_list: D018076:DNA, Complementary; D053594:Myeloid Differentiation Factor 88; D051217:Toll-Like Receptor 9; D014409:Tumor Necrosis Factor-alpha