title: The complement system in teleost fish: progress of post-homolog-hunting researches.
abstract: Studies on the complement system of bony fish are now finishing a stage of homologue-hunting identification of the components, unveiling existence of almost all the orthologues of mammalian complement components in teleost. Genomic and transcriptomic data for several teleost species have contributed much for the homologue-hunting research progress. Only an exception is identification of orthologues of mammalian complement regulatory proteins and complement receptors. It is of particular interest that teleost complement components often exist as multiple isoforms with possible functional divergence. This review summarizes research progress of teleost complement system following the molecular identification and sequence analysis of the components. The findings of extensive expression analyses of the complement components with special emphasis of their prominent extrahepatic expression, acute-phase response to immunostimulation and various microbial infections, and ontogenic development including maternal transfer are discussed to infer teleost-specific functions of the complement system. Importance of the protein level characterization of the complement components is also emphasized, especially for understanding of the isotypic diversity of the components, a unique feature of teleost complement system.
authors.affiliation: Laboratory of Marine Biochemistry, Department of Bioscience and Biotechnology, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, Fukuoka 812-8581, Japan. mikimnakao@kyudai.jp
authors.forename: Miki
authors.initials: M
authors.lastname: Nakao
authors.forename: Masakazu
authors.initials: M
authors.lastname: Tsujikura
authors.forename: Satoko
authors.initials: S
authors.lastname: Ichiki
authors.forename: Tam K
authors.initials: TK
authors.lastname: Vo
authors.forename: Tomonori
authors.initials: T
authors.lastname: Somamoto
mesh_terms: D000210:Acute-Phase Reaction / Q000235:genetics / Q000276:immunology; D000818:Animals; D001419:Bacteria / Q000276:immunology; D001424:Bacterial Infections / Q000276:immunology* / Q000382:microbiology; D003165:Complement System Proteins / Q000145:classification / Q000235:genetics / Q000276:immunology*; D019143:Evolution, Molecular; D029941:Fish Proteins / Q000145:classification / Q000235:genetics / Q000276:immunology*; D005399:Fishes / Q000235:genetics; D005658:Fungi / Q000276:immunology; D007113:Immunity, Innate; D009181:Mycoses / Q000276:immunology* / Q000382:microbiology; D010802:Phylogeny; D011951:Receptors, Complement / Q000235:genetics / Q000276:immunology*; D017386:Sequence Homology, Amino Acid; D014777:Virus Diseases / Q000276:immunology* / Q000821:virology; D014780:Viruses / Q000276:immunology
chemical_list: D029941:Fish Proteins; D011951:Receptors, Complement; D003165:Complement System Proteins