title: Dynamic evolution of CIKS (TRAF3IP2/Act1) in metazoans.
abstract: CIKS (TRAF3IP2/Act1) is important for inflammatory responses and autoimmunity control through its dual functions in CD40L/BAFF and IL17 signaling in mammalians. In this study, we performed comparative and evolutionary analyses of CIKSs from metazoans. Although nematode (Caenorabditis elegans) and sea urchin (Strongylocentrotus purpuratus) have IL17 and IL17 receptors, we found no CIKS in their genomes. The ancient CIKS-like (CIKSL) genes from the invertebrates lottia (Lottia gigantea) and amphioxus (Branchiostoma floridae) have an additional DEATH domain compared with other CIKSLs/CIKSs. Our data suggest that the ancient CIKSL evolved into early chordate CIKS possibly through gene tandem duplication and gene fission. Based on phylogenetic and synteny analyses, vertebrate CIKS genes are divided into two groups, one of which is orthologous to human CIKS and the other is paralogous. Expression analysis indicated that cephalochordata amphioxus IL17 together with CIKS might play an ancient and conserved role in host defense against bacterial infections. During the evolutionary process, the CIKS genes have obtained more and more functions through cooperation with other genes.
authors.affiliation: Laboratory of Developmental Immunology, School of Life Sciences, Shandong, University, Jinan 250100, China.
authors.forename: Baojun
authors.initials: B
authors.lastname: Wu
authors.forename: Meng
authors.initials: M
authors.lastname: Jin
authors.forename: Jing
authors.initials: J
authors.lastname: Gong
authors.forename: Xiumin
authors.initials: X
authors.lastname: Du
authors.forename: Zengliang
authors.initials: Z
authors.lastname: Bai
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D017173:Caenorhabditis elegans / Q000235:genetics; D002645:Chickens / Q000235:genetics; D002816:Chordata, Nonvertebrate / Q000235:genetics; D019143:Evolution, Molecular; D005399:Fishes / Q000235:genetics; D016678:Genome; D006801:Humans; D020381:Interleukin-17 / Q000235:genetics*; D007798:Lampreys / Q000235:genetics; D051379:Mice; D008974:Mollusca / Q000235:genetics; D009348:Nematoda / Q000235:genetics; D010802:Phylogeny; D053218:Receptors, Death Domain / Q000235:genetics; D053722:Receptors, Interleukin-17 / Q000235:genetics*; D012615:Sea Anemones / Q000235:genetics; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D012754:Sharks / Q000235:genetics; D047270:Strongylocentrotus purpuratus / Q000235:genetics; D047988:Tumor Necrosis Factor Receptor-Associated Peptides and Proteins / Q000235:genetics*; D014981:Xenopus / Q000235:genetics
chemical_list: D020381:Interleukin-17; D053218:Receptors, Death Domain; D053722:Receptors, Interleukin-17; D047988:Tumor Necrosis Factor Receptor-Associated Peptides and Proteins