Characterization of twin toll-like receptors from rainbow trout (Oncorhynchus mykiss): evolutionary relationship and induced expression by Aeromonas salmonicida salmonicida.
Structure and function of factors contributing to the innate immune system of lower vertebrates, including fish are only sparsely characterized. We retrieved with RT-PCR cDNA copies of two closely related Toll-like receptors (TLR) from liver RNA of the rainbow trout (Oncorhynchus mykiss). The cDNA sequences are homologous to 95.6%. The phylogenetic analysis of their deduced amino acid sequences places these twin factors closely to other known TLRs from fish. The twin factors are equally expressed in all tissues analysed, most abundantly in spleen and head kidney and lowest in adipose tissue. Formalin-inactivated Aeromonas salmonicida pathogens induce their expression up to eight-fold in vitro in peripheral blood lymphocytes and in tissues from spleen and head kidney. Our sequence information will be useful to establish expression constructs for these factors necessary to analyse the pathogen specific signal transduction activating the innate immune defence in fish.
Rebl
Alexander
A
Research Institute for the Biology of Farm Animals (FBN), Wilhelm-Stahl-Allee 2, 18196 Dummerstorf, Germany.
Siegl
Edda
E
Köllner
Bernd
B
Fischer
Uwe
U
Seyfert
Hans-Martin
HM
D048409:Aeromonas salmonicida / Q000254:growth & development* / Q000276:immunology; D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D000818:Animals; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics; D005393:Fish Diseases / Q000235:genetics / Q000276:immunology / Q000382:microbiology; D020869:Gene Expression Profiling; D016905:Gram-Negative Bacterial Infections / Q000235:genetics / Q000276:immunology / Q000382:microbiology; D007113:Immunity, Innate / Q000276:immunology; D007963:Leukocytes, Mononuclear / Q000276:immunology; D008969:Molecular Sequence Data; D017686:Oncorhynchus mykiss / Q000235:genetics* / Q000276:immunology / Q000382:microbiology; D010802:Phylogeny; D020033:Protein Isoforms / Q000235:genetics; D017434:Protein Structure, Tertiary; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D013154:Spleen / Q000276:immunology / Q000378:metabolism; D051193:Toll-Like Receptors / Q000235:genetics*; D015854:Up-Regulation
D018076:DNA, Complementary; D020033:Protein Isoforms; D051193:Toll-Like Receptors