title: Characterization of C-C chemokine receptor subfamily in teleost fish.
abstract: Chemokines and their receptors play important roles in nervous and immune systems. Little information, however, exists concerning this gene family in teleost fish. In the present study, 17 C-C chemokine receptors genes were identified from Danio rerio, 9 from Gasterosteus aculeatus, 10 from Oryzias latipes, 8 from Takifugu rubripes and 5 from Tetraodon nigroviridis. Phylogenetic analysis showed that the orthologs to mammalian CCR6, 7, 8, 9 and CCRL1 receptors were evident in zebrafish, but the clear orthologs to mammalian CCR1, 2, 3, 4, 5 and 10 were not found in zebrafish. The gene structure of zebrafish CCR (zfCCR) was further analyzed. The open reading frame of zfCCR3-1, zfCCR3-3, zfCCR6-1, zfCCR6-2, zfCCR8-2 contain one exon, and two exons were identified for zfCCR2-1, zfCCR2-2, zfCCR4 and zfCCRL1-1, three exons for zfCCR3-2, zfCCR5 and zfCCR7, four exons for zfCCR8-1 and zfCCR9-1. The expression analyses showed that in zebrafish, most C-C chemokine receptor genes were expressed in fertilized eggs and oocytes, and all the receptor genes were expressed in larval stages. The zfCCR2-2, zfCCR3-1, zfCCR4 and zfCCR6-2 genes were expressed in all normal organs examined, whereas not for zfCCR2-1, zfCCR3-3, zfCCR6-1, zfCCR8-1, zfCCR9-2 and zfCCRL1-2. The expression of zfCCR3-2, zfCCR5, zfCCR7, zfCCR9-1 and zfCCRL1-1 were detected in the majority organs, and zfCCR8-2 and zfCCR8-3 detected only in brain. The differential expression pattern of different paralogues in organs may indicate their difference in function, which requires further investigation.
authors.affiliation: State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei Province 430072, PR China.
authors.forename: Y
authors.initials: Y
authors.lastname: Liu
authors.forename: M X
authors.initials: MX
authors.lastname: Chang
authors.forename: S G
authors.initials: SG
authors.lastname: Wu
authors.forename: P
authors.initials: P
authors.lastname: Nie
mesh_terms: D000818:Animals; D005091:Exons / Q000235:genetics; D005399:Fishes / Q000235:genetics*; D018507:Gene Expression Regulation, Developmental; D016678:Genome / Q000235:genetics; D010802:Phylogeny; D054388:Receptors, CCR / Q000235:genetics*; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid
chemical_list: D054388:Receptors, CCR