title: The C1q domain containing proteins of the Mediterranean mussel Mytilus galloprovincialis: a widespread and diverse family of immune-related molecules.
abstract: The key component of the classical complement pathway C1q is regarded as a major connecting link between innate and acquired immunity due to the highly adaptive binding properties of its trimeric globular domain gC1q. The gC1q domain also characterizes many non-complement proteins involved in a broad range of biological processes including apoptosis, inflammation, cell adhesion and cell differentiation. In molluscs and many other invertebrates lacking of adaptive immunity, C1q domain containing (C1qDC) proteins are abundant, they most probably emerged as lectins and subsequently evolved in a specialized class of pattern recognition molecules through the expanding interaction properties of gC1q. Here we report the identification of 168 C1qDC transcript sequences of Mytilus galloprovincialis. The remarkable abundance of C1qDC transcripts in the Mediterranean mussel suggests an evolutionary strategy of gene duplication, functional diversification and selection of many specific C1qDC variants. A comprehensive transcript sequence survey in Protostomia also revealed that the C1qDC family expansion observed in mussel could have occurred in some specific taxa independently from the events leading to the establishment of a large complement of C1qDC genes in the Chordates lineage.
authors.affiliation: Department of Life Sciences, University of Trieste, Trieste, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Gerdol
authors.forename: Chiara
authors.initials: C
authors.lastname: Manfrin
authors.forename: Gianluca
authors.initials: G
authors.lastname: De Moro
authors.forename: Antonio
authors.initials: A
authors.lastname: Figueras
authors.forename: Beatriz
authors.initials: B
authors.lastname: Novoa
authors.forename: Paola
authors.initials: P
authors.lastname: Venier
authors.forename: Alberto
authors.initials: A
authors.lastname: Pallavicini
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D015922:Complement C1q / Q000737:chemistry / Q000235:genetics*; D057225:Data Mining; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D006434:Hemocytes / Q000276:immunology / Q000382:microbiology / Q000502:physiology; D008522:Mediterranean Sea; D008969:Molecular Sequence Data; D049878:Mytilus / Q000235:genetics / Q000276:immunology* / Q000382:microbiology; D009928:Organ Specificity; D017434:Protein Structure, Tertiary; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D014158:Transcription, Genetic
chemical_list: D015922:Complement C1q