title: Sequence analysis of a normalized cDNA library of Mytilus edulis hemocytes exposed to Vibrio splendidus LGP32 strain.
abstract: In the past decades, reports on bivalves' pathogens and associated mortalities have steadily increased. To face pathogenic micro-organisms, bivalves rely on innate defenses established in hemocytes which are essentially based on phagocytosis and cytotoxic reactions. As a step towards a better understanding of the molecular mechanisms involved in the mussel Mytilus edulis innate immune system, we constructed and sequenced a normalized cDNA library specific to M. edulis hemocytes unchallenged (control) and challenged with Vibrio splendidus LGP32 strain for 2, 4 and 6 h. A total of 1,024,708 nucleotide reads have been generated using 454 pyrosequencing. These reads have been assembled and annotated into 19,622 sequences which we believe cover most of the M. edulis hemocytes transcriptome. These sequences were successfully assigned to biological process, cellular component, and molecular function Gene Ontology (GO) categories. Several transcripts related to immunity and stress such as some fibrinogen related proteins and Toll-like receptors, the complement C1qDC, some antioxidant enzymes and antimicrobial peptides have already been identified. In addition, Toll-like receptors signaling pathways and the lysosome and apoptosis mechanisms were compared to KEGG reference pathways. As an attempt for large scale RNA sequencing, this study focuses on identifying and annotating transcripts from M. edulis hemocytes regulated during an in vitro experimental challenge with V. splendidus. The bioinformatic analysis provided a reference transcriptome, which could be used in studies aiming to quantify the level of transcripts using high-throughput analysis such as RNA-Seq.
authors.affiliation: Laboratory of Ecotoxicology, University of Le Havre, 25 rue Philippe Lebon, BP540, 76058 Le Havre, France ; Institute of Marine Science, University of Quebec at Rimouski, 310 allée des Ursulines, Rimouski, Québec, Canada G5L 3A1 ; Department of Pathology & Microbiology, Atlantic Veterinary College (AVC), University of Prince Edward Island, 550 University Avenue, Charlottetown, PE, Canada C1A 4P3.
authors.forename: Marion
authors.initials: M
authors.lastname: Tanguy
authors.affiliation: Department of Pathology & Microbiology, Atlantic Veterinary College (AVC), University of Prince Edward Island, 550 University Avenue, Charlottetown, PE, Canada C1A 4P3.
authors.forename: Patty
authors.initials: P
authors.lastname: McKenna
authors.affiliation: Institute of Marine Science, University of Quebec at Rimouski, 310 allée des Ursulines, Rimouski, Québec, Canada G5L 3A1.
authors.forename: Sophie
authors.initials: S
authors.lastname: Gauthier-Clerc
authors.affiliation: Institute of Marine Science, University of Quebec at Rimouski, 310 allée des Ursulines, Rimouski, Québec, Canada G5L 3A1.
authors.forename: Jocelyne
authors.initials: J
authors.lastname: Pellerin
authors.affiliation: Laboratory of Ecotoxicology, University of Le Havre, 25 rue Philippe Lebon, BP540, 76058 Le Havre, France.
authors.forename: Jean-Michel
authors.initials: JM
authors.lastname: Danger
authors.affiliation: Department of Pathology & Microbiology, Atlantic Veterinary College (AVC), University of Prince Edward Island, 550 University Avenue, Charlottetown, PE, Canada C1A 4P3 ; British Columbia Centre for Aquatic Health Sciences (BC CAHS), 871A Island Highway, Campbell River, BC, Canada V9W 2C2.
authors.forename: Ahmed
authors.initials: A
authors.lastname: Siah
keywords: 454 Pyrosequencing; Hemocyte; Mytilus edulis; Transcriptome; Vibrio splendidus