title: HcToll3 was involved in anti-Vibrio defense in freshwater pearl mussel, Hyriopsis cumingii.
abstract: Toll-like receptors (TLRs) play an important role in the activation of innate immune response but their functions in bivalves remain largely unknown. In this study, we identified a TLR from the freshwater pearl mussel Hyriopsis cumingii (HcToll3) and investigated its functions in immunity. The full-length cDNA of HcToll3 is 3852 bp and includes an open reading frame (ORF) of 3228 bp that encodes a polypeptide of 1075 amino acids. The predicted HcToll3 protein shares similar structural characteristics with other known Toll family proteins. Quantitative real-time PCR analysis revealed that HcToll3 mRNA is broadly expressed in all of the examined tissues; its transcript level was significantly up-regulated by challenge with gram-negative bacteria Vibrio parahaemolyticus or lipopolysaccharide, but not gram-positive Staphylococcus aureus or peptidoglycan. RNA interference by siRNA results showed that HcToll3 regulated expression of whey acidic protein (HcWAP) and lysozymes (HcLyso1 and HcLyso2) in vivo and knockdown of HcToll3 suppressed the elimination of V. parahaemolyticus. These findings suggest that HcToll3 might be involved in anti-Vibrio defense in H. cumingii.
authors.affiliation: College of Life Science, Henan Normal University, Xinxiang, Henan 453007, China; Division of Plant Sciences, University of Missouri, Columbia, MO 65201, USA.
authors.forename: Hong-Wei
authors.initials: HW
authors.lastname: Zhang
authors.affiliation: Jiangsu Key Laboratory for Biodiversity & Biotechnology and Jiangsu Key Laboratory for Aquatic Crustacean Diseases, College of Life Sciences, Nanjing Normal University, Nanjing 210046, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Huang
authors.affiliation: College of Life Science, Henan Normal University, Xinxiang, Henan 453007, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Man
authors.affiliation: College of Life Science, Henan Normal University, Xinxiang, Henan 453007, China.
authors.forename: Yue
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Co-Innovation Center for Marine Bio-Industry Technology of Jiangsu Province, Lianyungang, Jiangsu 222005, China; Jiangsu Key Laboratory for Biodiversity & Biotechnology and Jiangsu Key Laboratory for Aquatic Crustacean Diseases, College of Life Sciences, Nanjing Normal University, Nanjing 210046, China. Electronic address: huikaimin@hotmail.com.
authors.forename: Kai-Min
authors.initials: KM
authors.lastname: Hui
authors.affiliation: Co-Innovation Center for Marine Bio-Industry Technology of Jiangsu Province, Lianyungang, Jiangsu 222005, China; Jiangsu Key Laboratory for Biodiversity & Biotechnology and Jiangsu Key Laboratory for Aquatic Crustacean Diseases, College of Life Sciences, Nanjing Normal University, Nanjing 210046, China. Electronic address: yinshaowu@163.com.
authors.forename: Shao-Wu
authors.initials: SW
authors.lastname: Yin
authors.affiliation: College of Life Science, Henan Normal University, Xinxiang, Henan 453007, China. Electronic address: zxwhtu@163.com.
authors.forename: Xiao-Wen
authors.initials: XW
authors.lastname: Zhang
mesh_terms: D000818:Animals; D007113:Immunity, Innate; D060888:Real-Time Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D051196:Toll-Like Receptor 3 / Q000235:genetics* / Q000378:metabolism; D049876:Unionidae / Q000235:genetics* / Q000276:immunology* / Q000382:microbiology; D014736:Vibrio parahaemolyticus / Q000502:physiology*
chemical_list: D051196:Toll-Like Receptor 3
keywords: Bacterial clearance; Hyriopsis cumingii; Innate immunity; RNAi; Toll like receptor