title: Gene duplication of the seventh component of complement in rainbow trout.
abstract: The seventh component of complement is a single-chain plasma glycoprotein that is involved in the cytolytic phase of complement activation through a sequence of polymerization reactions with other terminal components. We have previously isolated and characterized a C7 gene in rainbow trout (Oncorhynchus mykiss). Here, we report the cloning of a second trout C7 gene (C7-2). The deduced amino acid sequence of the C7-2 gene exhibits 43 and 50% identity with human C7 and trout C7-1, respectively. The structural motifs of trout C7-2 resemble those of mammalian C7 more than trout C7-1, and the cysteine backbone shows a high degree of conservation. C7-2 presents a different tissue expression profile from trout C7-1, which correlates with that of mammalian counterparts. Although duplication of complement genes is a common observation in teleost fish, this is the first report of two gene isotypes of a terminal membrane attack complex/perforin complement component in any organism.
authors.affiliation: Department of Biology, School of Medicine, University of Patras, Rion Patras, 26500, Greece. zarkadis@med.upatras.gr.
authors.forename: Anastasios D
authors.initials: AD
authors.lastname: Papanastasiou
authors.forename: Ioannis K
authors.initials: IK
authors.lastname: Zarkadis
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D003184:Complement C7 / Q000235:genetics*; D020440:Gene Duplication; D006801:Humans; D008969:Molecular Sequence Data; D017686:Oncorhynchus mykiss / Q000235:genetics*; D010802:Phylogeny; D017386:Sequence Homology, Amino Acid
chemical_list: D003184:Complement C7