Lipopolysaccharide-induced gene expression of interleukin-1 receptor-associated kinase 4 and interleukin-1β in roughskin sculpin (Trachidermus fasciatus).
Toll-like receptor (TLR) signaling pathway plays a crucial role in innate immune responses. In the present study, we first identified and characterized a key TLR pathway signal transduction molecule interleukin-1 receptor-associated kinase 4 (IRAK-4), and an important signal-out molecule interleukin-1β (IL-1β) from roughskin sculpin (Trachidermus fasciatus). IRAK-4 had an open reading frame (ORF) of 1401 bp, which encoded a protein of 467 amino acids with a highly conserved death domain (DD) and a serine/threonine/tyrosine protein kinase domain (STYKc). The full-length cDNA of IL-1β was 1242 bp with a 756 bp ORF, encoding a protein of 252 amino acids. Neither a signal peptide nor an IL-1β-converting enzyme (ICE) cleavage site was detected in this protein. Both genes were broadly expressed in all the ten examined tissues, with the highest transcript level in the skin, indicating that the host could trigger rapid immune responses in infected tissues through TLR signaling pathway. Quantitative real-time polymerase chain reaction was employed to investigate their temporal expression profiles post lipopolysaccharide challenge. The transcripts of both genes were significantly increased in the skin, blood, liver, spleen, and brain. It was shown that the transcript of IL-1β was dramatically induced to 700 times higher than that of the control group in the blood and liver. These results indicate that TLR signaling process may play an important role in fish immune response against microbial infections.
Ocean College, Shandong University (Weihai), Weihai 264209, PR China.
Yingying
Y
Liu
Shanshan
S
Yu
Yingmei
Y
Chai
Qiuxia
Q
Zhang
Hui
H
Yang
Qian
Q
Zhu
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D004926:Escherichia coli / Q000502:physiology; D029941:Fish Proteins / Q000737:chemistry / Q000235:genetics* / Q000276:immunology* / Q000378:metabolism; D005399:Fishes / Q000235:genetics* / Q000276:immunology*; D020869:Gene Expression Profiling / Q000662:veterinary; D015971:Gene Expression Regulation, Enzymologic; D007113:Immunity, Innate; D007274:Injections, Intraperitoneal / Q000662:veterinary; D036341:Intercellular Signaling Peptides and Proteins / Q000737:chemistry / Q000235:genetics* / Q000276:immunology* / Q000378:metabolism; D053592:Interleukin-1 Receptor-Associated Kinases / Q000737:chemistry / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D053583:Interleukin-1beta / Q000737:chemistry / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D008070:Lipopolysaccharides / Q000276:immunology; D008969:Molecular Sequence Data; D009928:Organ Specificity; D010802:Phylogeny; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction / Q000662:veterinary; D016415:Sequence Alignment / Q000662:veterinary; D015398:Signal Transduction
D018076:DNA, Complementary; D029941:Fish Proteins; D036341:Intercellular Signaling Peptides and Proteins; D053583:Interleukin-1beta; D008070:Lipopolysaccharides; D012333:RNA, Messenger; D053592:Interleukin-1 Receptor-Associated Kinases