title: Molecular cloning, expression pattern, and phylogenetic analysis of a tetraspanin CD82-like molecule in lamprey Lampetra japonica.
abstract: CD82, a member of the tetraspanins, is originally identified as an accessory molecule in T cell activation, and it participates in the formation of immune synapse both in T cells and antigen-presenting cells of jawed vertebrates. In the present study, a CD82 homologous complementary DNA (cDNA) sequence is identified in the lamprey Lampetra japonica. The open reading frame of this sequence is 801 bp long and encodes a 266-amino acid protein. The multialignment of this sequence with several typical CD82s and CD37s of jawed vertebrates shows that it also possesses their conserved four transmembrane domains and a six-cysteine motif Cys-Cys-Gly…Cys-Ser-Cys…Cys…Cys, which is a characteristic motif of CD82 and CD37 vertebrate tetraspanin sequences. Since it is close to CD82s in sequence similarity, we name it as Lja-CD82-like. From the distribution profile of the conserved motifs of CD82-like, CD82, and CD37 molecules from molluscas to mammals, it seems that the CD82s and CD37s evolved from a common ancestral gene through a gene duplication event to their modern forms by a short insertion or substitution approaches. The phylogenetic analysis indicated that CD82 and CD37 molecules of jawed vertebrates originated from a common ancestral gene which is close to agnathan CD82-like and evolved into two distinct paralogous groups maybe after the divergence of jawed and jawless vertebrates. An expression vector with trigger factor (TF) was constructed to ensure that Lja-CD82-like express in prokaryotic expression host. The expressions of Lja-CD82-like messenger RNA (mRNA) and protein in immune-related tissues of lamprey were detected by real-time quantitative polymerase chain reaction and western blotting. Results showed that the mRNA and the protein levels of Lja-CD82-like were significantly upregulated in lymphocyte-like cells, gills, and supraneural myeloid bodies after stimulation with mixed antigens, respectively. Our data provided a foundation for the further study of Lja-CD82-like and its role in immune response process of jawless vertebrates.
authors.affiliation: College of Life Science, Liaoning Normal University, Dalian, 116029, China.|Lamprey Research Center, Liaoning Normal University, Dalian, 116029, China.
authors.forename: Xiaoping
authors.initials: X
authors.lastname: Zhang
authors.affiliation: College of Life Science, Liaoning Normal University, Dalian, 116029, China.|Lamprey Research Center, Liaoning Normal University, Dalian, 116029, China.
authors.forename: Xueying
authors.initials: X
authors.lastname: Song
authors.affiliation: College of Life Science, Liaoning Normal University, Dalian, 116029, China.|Lamprey Research Center, Liaoning Normal University, Dalian, 116029, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Su
authors.affiliation: College of Life Science, Liaoning Normal University, Dalian, 116029, China.|Lamprey Research Center, Liaoning Normal University, Dalian, 116029, China.
authors.forename: Meng
authors.initials: M
authors.lastname: Gou
authors.affiliation: College of Life Science, Liaoning Normal University, Dalian, 116029, China.|Lamprey Research Center, Liaoning Normal University, Dalian, 116029, China.
authors.forename: Hao
authors.initials: H
authors.lastname: Wang
authors.affiliation: College of Life Science, Liaoning Normal University, Dalian, 116029, China. liuxin@lnnu.edu.cn.|Lamprey Research Center, Liaoning Normal University, Dalian, 116029, China. liuxin@lnnu.edu.cn.
authors.forename: Xin
authors.initials: X
authors.lastname: Liu
authors.affiliation: College of Life Science, Liaoning Normal University, Dalian, 116029, China. liqw@263.net.|Lamprey Research Center, Liaoning Normal University, Dalian, 116029, China. liqw@263.net.
authors.forename: Qingwei
authors.initials: Q
authors.lastname: Li
mesh_terms: D020816:Amino Acid Motifs; D000818:Animals; D003001:Cloning, Molecular; D017124:Conserved Sequence; D019143:Evolution, Molecular; D029941:Fish Proteins / Q000737:chemistry / Q000235:genetics*; D006801:Humans; D051861:Kangai-1 Protein / Q000737:chemistry / Q000235:genetics; D007798:Lampreys / Q000235:genetics*; D008214:Lymphocytes; D010802:Phylogeny; D017386:Sequence Homology, Amino Acid; D059470:Tetraspanins / Q000737:chemistry / Q000235:genetics*; D059467:Transcriptome
chemical_list: D029941:Fish Proteins; D051861:Kangai-1 Protein; D059470:Tetraspanins
keywords: CD82; Expression pattern; Immune response; Lampetra japonica; Molecular evolution