title: A comprehensive analysis of the germline and expressed TCR repertoire in White Peking duck.
abstract: Recently, many immune-related genes have been extensively studied in ducks, but relatively little is known about their TCR genes. Here, we determined the germline and expressed repertoire of TCR genes in White Peking duck. The genomic organization of the duck TCRα/δ, TCRγ and unconventional TCRδ2 loci are highly conserved with their counterparts in mammals or chickens. By contrast, the duck TCRβ locus is organized in an unusual pattern, (Vβ)n-Dβ-(Jβ)2-Cβ1-(Jβ)4-Cβ2, which differs from the tandem-aligned clusters in mammals or the translocon organization in some teleosts. Excluding the first exon encoding the immunoglobulin domain, the subsequent exons of the two Cβ show significant diversity in nucleotide sequence and exon structure. Based on the nucleotide sequence identity, 49 Vα, 30 Vδ, 13 Vβ and 15 Vγ unique gene segments are classified into 3 Vα, 5 Vδ, 4 Vβ and 6 Vγ subgroups, respectively. Phylogenetic analyses revealed that most duck V subgroups, excluding Vβ1, Vγ5 and Vγ6, have closely related orthologues in chicken. The coding joints of all cDNA clones demonstrate conserved mechanisms that are used to increase junctional diversity. Collectively, these data provide insight into the evolution of TCRs in vertebrates and improve our understanding of the avian immune system.
authors.affiliation: State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, 100193, China.|Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, 100193, China.
authors.forename: Zhi
authors.initials: Z
authors.lastname: Yang
authors.affiliation: Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, College of Animal Science and Veterinary Medicine, Shandong Agricultural University, Taian, 271018, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Sun
authors.affiliation: State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, 100193, China.
authors.forename: Yonghe
authors.initials: Y
authors.lastname: Ma
authors.affiliation: State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, 100193, China.
authors.forename: Zhenrong
authors.initials: Z
authors.lastname: Li
authors.affiliation: National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, 100193, China.
authors.forename: Liming
authors.initials: L
authors.lastname: Ren
authors.affiliation: State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, 100193, China.
authors.forename: Haitang
authors.initials: H
authors.lastname: Han
authors.affiliation: Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, College of Animal Science and Veterinary Medicine, Shandong Agricultural University, Taian, 271018, China.
authors.forename: Yunliang
authors.initials: Y
authors.lastname: Jiang
authors.affiliation: State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, 100193, China.
authors.forename: Yaofeng
authors.initials: Y
authors.lastname: Zhao
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D022801:Complementarity Determining Regions / Q000235:genetics; D018076:DNA, Complementary / Q000235:genetics; D004372:Ducks / Q000235:genetics / Q000276:immunology*; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D056426:Genetic Loci; D014644:Genetic Variation; D016678:Genome; D005854:Germ Cells / Q000378:metabolism*; D007135:Immunoglobulin Variable Region / Q000235:genetics; D008322:Mammals / Q000235:genetics / Q000276:immunology; D010802:Phylogeny; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011948:Receptors, Antigen, T-Cell / Q000737:chemistry / Q000378:metabolism*
chemical_list: D022801:Complementarity Determining Regions; D018076:DNA, Complementary; D007135:Immunoglobulin Variable Region; D012333:RNA, Messenger; D011948:Receptors, Antigen, T-Cell