title: Toll-like receptors and MyD88 adaptors in Mytilus: complete cds and gene expression levels.
abstract: TLR- and MyD88-related sequences have been previously investigated in Mytibase and then in new transcript reads obtained by Illumina technology from the mussel, Mytilus galloprovincialis. Based on full cds and domain organizations of virtual translations, we identified 23 Toll-like receptors (TLRs) and 3 MyD88 adaptors. MgTLRs can be arranged in 4 clusters according to extra-cellular LRR domain content. MgTLR-b, -i and -k were the only ones containing a multiple cysteine cluster (mccTLR), a domain composition also found in Drosophila Toll-1 and 18-wheeler. The 3 MyD88 we identified in M. galloprovincialis were also retrieved from Mytilus edulis, as well as MgTLR-b and -i. All MgTLRs were constitutively expressed in digestive gland whereas only 4 of them were also present in hemocytes. On the opposite, the 3 MgMyD88s were constitutively expressed in all the tissues. In vivo challenge of M. galloprovincialis with bacteria caused the up regulation of only MgTLR-i, but of all the 3 MgMyD88s. Highest response was induced by Gram-negative Vibrio anguillarum at 9h p.i. Injection of filamentous fungus, Fusarium oxysporum, resulted in up regulation of MgTLR-i and MgMyD88-c at 9h p.i. Such similar pattern of responses suggested MgMyD88-c represents the intra cytoplasm partner of MgTLR-i. Their interaction constituted the first cellular event revealing the existence of a Toll-signaling pathway in Lophotrochozoa.
authors.affiliation: Ecologie des Systèmes Marins et Côtiers EcoSym, Université Montpellier 2-CNRS, cc 093, place E. Bataillon, F-34095 Montpellier cedex 05, France.
authors.forename: Mylène
authors.initials: M
authors.lastname: Toubiana
authors.forename: Marco
authors.initials: M
authors.lastname: Gerdol
authors.forename: Umberto
authors.initials: U
authors.lastname: Rosani
authors.forename: Alberto
authors.initials: A
authors.lastname: Pallavicini
authors.forename: Paola
authors.initials: P
authors.lastname: Venier
authors.forename: Philippe
authors.initials: P
authors.lastname: Roch
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D016000:Cluster Analysis; D015870:Gene Expression; D005786:Gene Expression Regulation / Q000276:immunology; D005880:Gills / Q000378:metabolism; D006434:Hemocytes / Q000378:metabolism; D054884:Host-Pathogen Interactions / Q000276:immunology; D007113:Immunity, Innate; D008969:Molecular Sequence Data; D053594:Myeloid Differentiation Factor 88 / Q000235:genetics / Q000378:metabolism*; D049878:Mytilus / Q000276:immunology / Q000378:metabolism* / Q000382:microbiology; D009928:Organ Specificity; D010802:Phylogeny; D017434:Protein Structure, Tertiary; D015398:Signal Transduction / Q000276:immunology; D051193:Toll-Like Receptors / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D059467:Transcriptome; D014733:Vibrio / Q000276:immunology
chemical_list: D053594:Myeloid Differentiation Factor 88; D051193:Toll-Like Receptors