title: Immunoglobulin light chain (IGL) genes in torafugu: Genomic organization and identification of a third teleost IGL isotype.
abstract: Here, we report a genome-wide survey of immunoglobulin light chain (IGL) genes of torafugu (Takifugu rubripes) revealing multi-clusters spanning three separate chromosomes (v5 assembly) and 45 scaffolds (v4 assembly). Conventional sequence similarity searches and motif scanning approaches based on recombination signal sequence (RSS) motifs were used. We found that three IGL isotypes (L1, L2, and L3) exist in torafugu and that several loci for each isotype are present. The transcriptional orientations of the variable IGL (VL) segments were found to be either the same (in the L2 isotype) or opposite (in the L1 and L3 isotypes) to the IGL joining (JL) and constant (CL) segments, suggesting they can undergo rearrangement by deletion or inversion when expressed. Alignments of expressed sequence tags (ESTs) to corresponding germline gene segments revealed expression of the three IGL isotypes in torafugu. Taken together, our findings provide a genomic framework for torafugu IGL genes and show that the IG diversity of this species could be attributed to at least three distinct chromosomal regions.
authors.affiliation: State Key Laboratory of Biotherapy &Collaborative Innovation Center for Biotherapy, West China Hospital, Sichuan University, Chengdu 610041, China.|Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo, Tokyo 113-8657, Japan.
authors.forename: Xi
authors.initials: X
authors.lastname: Fu
authors.affiliation: Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo, Tokyo 113-8657, Japan.
authors.forename: Fengjun
authors.initials: F
authors.lastname: Zhang
authors.affiliation: School of Marine Bioscience, Kitasato University, Sagamihara, Kanagawa 252-0373, Japan.
authors.forename: Shugo
authors.initials: S
authors.lastname: Watabe
authors.affiliation: Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo, Tokyo 113-8657, Japan.
authors.forename: Shuichi
authors.initials: S
authors.lastname: Asakawa
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D007446:Chromosome Inversion / Q000235:genetics; D002875:Chromosomes / Q000235:genetics; D015321:Gene Rearrangement / Q000235:genetics; D056426:Genetic Loci; D016678:Genome; D007132:Immunoglobulin Isotypes / Q000235:genetics*; D007147:Immunoglobulin Light Chains / Q000737:chemistry / Q000235:genetics*; D010802:Phylogeny; D011995:Recombination, Genetic / Q000235:genetics; D023741:Takifugu / Q000235:genetics*
chemical_list: D007132:Immunoglobulin Isotypes; D007147:Immunoglobulin Light Chains