title: Characterizations and expression analyses of NF-κB and Rel genes in the Yesso scallop (Patinopecten yessoensis) suggest specific response patterns against Gram-negative infection in bivalves.
abstract: Rel/NF-κB (nuclear factor kappa-light-chain-enhancer of activated B cells) genes are evolutionarily conserved and play a pivotal role in several physiological events. They have been extensively studied from various species, including both vertebrates and invertebrates. However, the Rel/NF-κB genes have not been systematically characterized in bivalves. In this study, we identified and characterized PyNF-κB and PyRel in the Yesso scallop (Patinopecten yessoensis). Phylogenetic and protein structural analyses were conducted to determine the identities and evolutionary relationships of Rel/NF-κB genes in Yesso scallop. Compared with the Rel/NF-κB genes from vertebrate species, the PyNF-κB and PyRel are relatively conserved in their structural features, but there were no paralogs found in P. yessoensis or other invertebrates. To gain insights into the roles of Rel/NF-κB genes during the innate immune response in scallop, quantitative real-time PCR was used to investigate the expression profiles of these genes at different developmental stages, in healthy adult tissues and in the hemolymph after bacterial infection with Micrococcus luteus and Vibrio anguillarum. The real-time PCR results indicated the abundance of PyNF-κB in the first four embryonic stages, including oocytes, fertilized eggs, morulae and blastulae. By contrast, PyRel was abundantly expressed in blastulae, trochophores and D-shaped larvae. In adult scallops, PyNF-κB and PyRel were ubiquitously expressed in most healthy tissues and highly expressed in most of the immune related tissues. Both genes were significantly up-regulated during the acute phase (3 h) after infection with Gram-positive (M. luteus) and negative (V. anguillarum) bacteria, while the much higher expression level of PyNF-κB suggested the involvement of the extra immune deficiency (IMD)-like pathway against the Gram-negative bacterial infection. The complex pattern of Rel/NF-κB induced expression suggested that PyNF-κB and PyRel both have specific and cooperative roles in the acute immune responses to bacterial infection.
authors.affiliation: Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, 5 Yushan Road, Qingdao 266003, China.
authors.forename: Ruojiao
authors.initials: R
authors.lastname: Li
authors.affiliation: Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, 5 Yushan Road, Qingdao 266003, China.
authors.forename: Ru
authors.initials: R
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, 5 Yushan Road, Qingdao 266003, China.
authors.forename: Lu
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, 5 Yushan Road, Qingdao 266003, China.
authors.forename: Jiajun
authors.initials: J
authors.lastname: Zou
authors.affiliation: Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, 5 Yushan Road, Qingdao 266003, China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Xing
authors.affiliation: Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, 5 Yushan Road, Qingdao 266003, China.
authors.forename: Huaiqian
authors.initials: H
authors.lastname: Dou
authors.affiliation: 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: Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, 5 Yushan Road, Qingdao 266003, China. Electronic address: lingling80@ouc.edu.cn.
authors.forename: Lingling
authors.initials: L
authors.lastname: Zhang
authors.affiliation: 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: 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; D001483:Base Sequence; D016000:Cluster Analysis; D017931:DNA Primers / Q000235:genetics; D057225:Data Mining; D005786:Gene Expression Regulation / Q000276:immunology*; D020573:Genes, rel / Q000235:genetics* / Q000276:immunology; D006090:Gram-Negative Bacteria / Q000276:immunology*; D008957:Models, Genetic; D008969:Molecular Sequence Data; D016328:NF-kappa B / Q000235:genetics* / Q000276:immunology; D049897:Pectinidae / Q000235:genetics* / Q000276:immunology* / Q000382:microbiology; D010802:Phylogeny; D060888:Real-Time Polymerase Chain Reaction; D017422:Sequence Analysis, DNA
chemical_list: D017931:DNA Primers; D016328:NF-kappa B
keywords: Gram-positive and gram-negative infection; IMD; Innate immune response; Patinopecten yessoensis; Rel/NF-κB