title: Molecular cloning, characterization, and expression analysis of the Muscovy duck Toll-like receptor 3 (MdTLR3) gene.
abstract: Toll-like receptor 3 (TLR3) is an important membrane-bound receptor for recognizing double-stranded RNA in innate immunity. In this study, we described the cloning and characterization of the Muscovy duck TLR3 (MdTLR3) gene. The full-length MdTLR3 cDNA (2,836 bp) encoded a polypeptide of 895 amino acids. The deduced amino acid sequence contained 4 main structural domains: a signal peptide, an extracellular leucine rich repeats domain, a transmembrane domain, and a Toll/IL-1 receptor domain. Quantitative real-time PCR analysis indicated that MdTLR3 mRNA was constitutively expressed in all sampled tissues of uninfected Muscovy duck except muscle. Expression of MdTLR3 in brain was signiﬁcantly upregulated at 24 h (1.94-fold, P < 0.05), reached a peak at 48 h (4.64-fold, P < 0.05), and recovered to normal levels at 72 h postinfection with the H5N1 highly pathogenic avian inﬂuenza virus. In contrast, MdTLR3 expression was downregulated during the test period in spleen and lung. These results implicated MdTLR3 was a novel member of the TLR family, which is involved in the early stage of antiviral innate immunity.
authors.affiliation: South China Agricultural University, Guangzhou, People's Republic of China.
authors.forename: P R
authors.initials: PR
authors.lastname: Jiao
authors.forename: L M
authors.initials: LM
authors.lastname: Wei
authors.forename: Y Q
authors.initials: YQ
authors.lastname: Cheng
authors.forename: R Y
authors.initials: RY
authors.lastname: Yuan
authors.forename: F
authors.initials: F
authors.lastname: Han
authors.forename: J
authors.initials: J
authors.lastname: Liang
authors.forename: W L
authors.initials: WL
authors.lastname: Liu
authors.forename: T
authors.initials: T
authors.lastname: Ren
authors.forename: C A
authors.initials: CA
authors.lastname: Xin
authors.forename: M
authors.initials: M
authors.lastname: Liao
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D003001:Cloning, Molecular; D004372:Ducks / Q000235:genetics / Q000378:metabolism*; D005786:Gene Expression Regulation / Q000502:physiology*; D053124:Influenza A Virus, H5N1 Subtype; D005585:Influenza in Birds / Q000378:metabolism / Q000821:virology; D008969:Molecular Sequence Data; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051196:Toll-Like Receptor 3 / Q000235:genetics / Q000378:metabolism*
chemical_list: D012333:RNA, Messenger; D051196:Toll-Like Receptor 3