title: MIF from mussel: coding sequence, phylogeny, polymorphism, 3D model and regulation of expression.
abstract: Three macrophage migration inhibitory factor (MIF)-related sequences were identified from a Mytilus galloprovincialis EST library. The consensus sequence included a 5'-UTR of 32 nucleotides, the complete ORF of 345 nucleotides, and a 3'-UTR of 349 nucleotides. As for other MIFs, M. galloprovincialis ORF does not include any signal or C-terminus extensions. The translated sequence of 115 amino acids possesses a molecular mass of 12,681.4, a pI of 6.27 and a stability index of 21.48. Its 3D structure resembles human MIF except for one shorter α-helix. Although evolutionary separated from ticks and vertebrates, Mg-MIF appeared to be closely related to Pinctada fucata and Haliotis, but not to Chlamys farreri and Biomphalaria glabrata. Numerous mutation points were observed within the Mg-MIF ORF, defining 11 amino acid variants within the mussels from Palavas-France and 14 amino acid variants within the mussels from Palermo-Italy. The 2 major variants from Palavas were identical to 2 of the 4 major variants from Palermo. In all the 18 Mg-MIF variants, residues involved in tautomerase and in oxidoreductase activities were conserved. Generally, one mussel expressed 2 Mg-MIF amino acid sequences but with different frequencies of occurrence. Mg-MIF is constitutively expressed principally in hemocytes and in the mantle. In contrast to other animal models, Mg-MIF expression was always down regulated following challenge by bacteria and fungi, confirming previous data obtained with microarray. Down regulation started as soon as 1 h and Mg-MIF expression returned to background 9-48 h after the challenge. Exception was regarding the yeast, Candidaalbicans, down-regulation between 9 and 72 h, suggesting yeast and bacteria-filamentous fungi trigger different mechanisms of elimination.
authors.affiliation: Marine Immunobiology Laboratory, University of Palermo, Via Archirafi 18, 90123 Palermo, Italy.
authors.forename: Maria-Giovanna
authors.initials: MG
authors.lastname: Parisi
authors.forename: Mylène
authors.initials: M
authors.lastname: Toubiana
authors.forename: Valentina
authors.initials: V
authors.lastname: Mangano
authors.forename: Nicolò
authors.initials: N
authors.lastname: Parrinello
authors.forename: Matteo
authors.initials: M
authors.lastname: Cammarata
authors.forename: Philippe
authors.initials: P
authors.lastname: Roch
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D020224:Expressed Sequence Tags; D005602:France; D020869:Gene Expression Profiling; D015723:Gene Library; D006434:Hemocytes; D007558:Italy; D008263:Macrophage Migration-Inhibitory Factors / Q000737:chemistry* / Q000235:genetics* / Q000276:immunology; D008958:Models, Molecular; D008969:Molecular Sequence Data; D049878:Mytilus / Q000235:genetics / Q000276:immunology* / Q000378:metabolism / Q000382:microbiology; D010802:Phylogeny; D016415:Sequence Alignment
chemical_list: D008263:Macrophage Migration-Inhibitory Factors