Yong Yan-Hong, Liu Shao-Feng, Hua Guo-Hong, Jia Ru-Min, Gooneratne Ravi, Zhao Yun-Tao, Liao Ming, Ju Xiang-Hong
Center of Modern Biochemistry, Guangdong Ocean University, Zhanjiang 524088, China.
Department of Animal Science, Guangdong Ocean University, Zhanjiang 524088, China.
Vet Immunol Immunopathol. 2018 Mar;197:31-38. doi: 10.1016/j.vetimm.2018.01.010.
Induction of the innate immune pathways is critical for early anti-viral defense. How geese recognize viral molecules and activate these pathways is not well understood. In mammals, Toll-like receptor 3 (TLR3) recognizes double-stranded RNA. Activation of TLR3 induces the activation of NF-кB and the production of type-I interferon. In this study, the goose TLR3 gene was cloned using rapid amplification of cDNA ends. Goose TLR3 encoded an 896-amino-acid protein, containing a signal secretion peptide, 14 extracellular leucine-rich repeat domains, a transmembrane domain, a Toll/interleukin-1 receptor signaling domain, and shared 46.7-84.4% homology with other species. Tissue expression of goose TLR3 varied markedly and was highest in the pancreas and lowest in the skin. Human embryonic kidney 293 cells transfected with goose TLR3 and NF-κB-luciferase-containing plasmids responded significantly to poly i:c. The expression of TLR3, IL-6 and IFN-γ mRNA, but not IL-1 mRNA, was significantly upregulated after poly i:c or high pathogenic avian influenza virus (H5N1) stimulation in goose peripheral blood mononuclear cells cultured in vitro. Furthermore, geese infected with H5N1 showed significant upregulation of TLR3, especially in the lung and brain. We conclude that goose TLR3 is a functional TLR3 homologue of the protein in other species and plays an important role in virus recognition.
先天免疫途径的诱导对于早期抗病毒防御至关重要。鹅如何识别病毒分子并激活这些途径尚不清楚。在哺乳动物中，Toll样受体3（TLR3）识别双链RNA。TLR3的激活诱导NF-κB的激活和I型干扰素的产生。在本研究中，使用cDNA末端快速扩增法克隆了鹅TLR3基因。鹅TLR3编码一种896个氨基酸的蛋白质，包含一个信号分泌肽、14个细胞外富含亮氨酸重复结构域、一个跨膜结构域、一个Toll/白细胞介素-1受体信号结构域，与其他物种的同源性为46.7%-84.4%。鹅TLR3的组织表达差异显著，在胰腺中最高，在皮肤中最低。用鹅TLR3和含NF-κB荧光素酶的质粒转染的人胚肾293细胞对聚肌苷酸胞嘧啶核苷酸（poly i:c）有显著反应。在体外培养的鹅外周血单核细胞中，poly i:c或高致病性禽流感病毒（H5N1）刺激后，TLR3、IL-6和IFN-γ mRNA的表达显著上调，但IL-1 mRNA未上调。此外，感染H5N1的鹅TLR3显著上调，尤其是在肺和脑中。我们得出结论，鹅TLR3是其他物种中该蛋白的功能性TLR3同源物，在病毒识别中起重要作用。
