title: Genome-wide identification and characterization of TRAF genes in the Yesso scallop (Patinopecten yessoensis) and their distinct expression patterns in response to bacterial challenge.
abstract: The tumor necrosis factor (TNF) receptor associated factors (TRAFs) are the major signal transducers for the TNF receptor superfamily and the interleukin-1 receptor/Toll-like receptor (IL-1R/TLR) superfamily, which regulate a variety of cellular activities and innate immune responses. TRAF genes have been extensively studied in various species, including vertebrates and invertebrates. However, as one of the key component of NF-κB pathway, TRAF genes have not been systematically characterized in marine invertebrates. In this study, we identified and characterized five TRAF genes, PyTRAF2, PyTRAF3, PyTRAF4, PyTRAF6 and PyTRAF7, in the Yesso scallop (Patinopecten yessoensis). Phylogenetic and protein structural analyses were conducted to determine their identities and evolutionary relationships. In comparison with the TRAF genes from vertebrate species, the structural features were all relatively conserved in the PyTRAF genes. To gain insights into the roles of TRAF genes during scallop innate immune responses, quantitative real-time PCR was used to investigate the expression profiles in the different stages of scallop development, in the healthy adult tissues, and in the hemocytes after bacterial infection with Micrococcus luteus and Vibrio anguillarum. Based on the qRT-PCR analysis, the expression of most of the PyTRAFs was significantly induced in the acute phases (3-6 h) after infection with Gram-positive (M. luteus) and Gram-negative (V. anguillarum) bacteria, and many more dramatic changes in PyTRAFs expression were observed after V. anguillarum challenge. Notably, the strong response in the up-regulation of PyTRAF6 post-bacterial challenge was distinct from that previously reported in scallops and crabs but was similar to that of other shellfish, Echinodermata and even teleost fish. The high level expressions of PyTRAFs in the hemocytes and the gill, and their specific expression patterns after challenges provide insights into the versatile roles and responses of TRAFs in the innate immune system against Gram-negative bacterial pathogens in bivalves.
authors.affiliation: Ministry of Education Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, 5 Yushan Road, Qingdao 266003, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Wang
authors.affiliation: Ministry of Education Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, 5 Yushan Road, Qingdao 266003, China. Electronic address: rjwang@ouc.edu.cn.
authors.forename: Ruijia
authors.initials: R
authors.lastname: Wang
authors.affiliation: Ministry of Education Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, 5 Yushan Road, Qingdao 266003, China.
authors.forename: Shuyue
authors.initials: S
authors.lastname: Wang
authors.affiliation: Ministry of Education Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, 5 Yushan Road, Qingdao 266003, China.
authors.forename: Mengran
authors.initials: M
authors.lastname: Zhang
authors.affiliation: Ministry of Education Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, 5 Yushan Road, Qingdao 266003, China.
authors.forename: Xiaoli
authors.initials: X
authors.lastname: Ma
authors.affiliation: Ministry of Education Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, 5 Yushan Road, Qingdao 266003, China.
authors.forename: Pingping
authors.initials: P
authors.lastname: Liu
authors.affiliation: Ministry of Education Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, 5 Yushan Road, Qingdao 266003, China.
authors.forename: Meiwei
authors.initials: M
authors.lastname: Zhang
authors.affiliation: Ministry of Education Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, 5 Yushan Road, Qingdao 266003, China.
authors.forename: Xiaoli
authors.initials: X
authors.lastname: Hu
authors.affiliation: Ministry of Education Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, 5 Yushan Road, Qingdao 266003, China.
authors.forename: Lingling
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Ministry of Education Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, 5 Yushan Road, Qingdao 266003, China. Electronic address: swang@ouc.edu.cn.
authors.forename: Shi
authors.initials: S
authors.lastname: Wang
authors.affiliation: Ministry of Education Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, 5 Yushan Road, Qingdao 266003, China.
authors.forename: Zhenmin
authors.initials: Z
authors.lastname: Bao
mesh_terms: D000818:Animals; D005786:Gene Expression Regulation; D006434:Hemocytes / Q000276:immunology; D007113:Immunity, Innate; D016982:Micrococcus luteus / Q000502:physiology*; D008969:Molecular Sequence Data; D009928:Organ Specificity; D049897:Pectinidae / Q000235:genetics* / Q000276:immunology / Q000378:metabolism / Q000382:microbiology; D010802:Phylogeny; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D060888:Real-Time Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D020539:Sequence Analysis, Protein; D047988:Tumor Necrosis Factor Receptor-Associated Peptides and Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D014733:Vibrio / Q000502:physiology*
chemical_list: D047988:Tumor Necrosis Factor Receptor-Associated Peptides and Proteins
keywords: Gram-positive and Gram-negative infection; Innate immune; Patinopecten yessoensis; PyTRAF