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Updated: May 27, 2026
09:37
An Integrated Approach for Microprotein Identification and Sequence Analysis
Published on: July 12, 2022
MIF from mussel: coding sequence, phylogeny, polymorphism, 3D model and regulation of expression
Maria-Giovanna Parisi1, Mylène Toubiana, Valentina Mangano
1Marine Immunobiology Laboratory, University of Palermo, Via Archirafi 18, 90123 Palermo, Italy.
Developmental and Comparative Immunology
|November 17, 2011
Summary
Researchers identified macrophage migration inhibitory factor (MIF)-related sequences in mussels. Mg-MIF expression is down-regulated by bacterial and fungal challenges, suggesting distinct immune responses.
Area of Science:
- Marine Biology
- Immunology
- Molecular Biology
Background:
- Macrophage migration inhibitory factor (MIF) plays a crucial role in immune responses across various species.
- Understanding MIF homologs in invertebrates like mussels (Mytilus galloprovincialis) can provide insights into conserved immune mechanisms.
Purpose of the Study:
- To identify and characterize macrophage migration inhibitory factor (MIF)-related sequences in Mytilus galloprovincialis.
- To investigate the expression patterns and potential immune functions of Mg-MIF in response to microbial challenges.
Main Methods:
- Expressed Sequence Tag (EST) library screening to identify MIF-related sequences.
- Sequence analysis including UTRs, ORF, and translated amino acid properties.
- 3D structure prediction and comparison with human MIF.
- Analysis of Mg-MIF variants and conserved active sites.
- Gene expression analysis (microarray and direct measurement) following bacterial and fungal challenges.
Main Results:
- Three MIF-related sequences were identified, with a consensus sequence containing 5'-UTR, ORF, and 3'-UTR.
- The translated Mg-MIF sequence (115 amino acids) showed structural similarities to human MIF but with variations.
- Multiple Mg-MIF variants were identified, with conserved residues for tautomerase and oxidoreductase activities.
- Mg-MIF is constitutively expressed in hemocytes and mantle, and its expression is significantly down-regulated upon challenge with bacteria and fungi.
Conclusions:
- Mytilus galloprovincialis possesses MIF-related sequences with conserved functional domains, indicating a role in innate immunity.
- The down-regulation of Mg-MIF expression in response to microbial pathogens suggests a unique immune evasion or modulation strategy in mussels.
- Differential responses to yeast versus bacteria/fungi indicate distinct immune activation pathways triggered by different microorganisms.
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