Signatures of diversifying selection and convergence acting on passerine Toll-like receptor 4 in an evolutionary context
Language English Country England, Great Britain Media print-electronic
Document type Journal Article, Research Support, Non-U.S. Gov't
PubMed
29772096
DOI
10.1111/mec.14724
Knihovny.cz E-resources
- Keywords
- TLR4 molecular phenotype, Toll-like receptors, functional evolution, host-pathogen interaction, surface charge distribution,
- MeSH
- Glycolipids chemistry genetics MeSH
- Host-Pathogen Interactions genetics MeSH
- Protein Conformation MeSH
- Ligands MeSH
- Lipid A analogs & derivatives chemistry genetics MeSH
- Lipopolysaccharides chemistry genetics MeSH
- Lymphocyte Antigen 96 chemistry genetics MeSH
- Microbiota genetics MeSH
- Evolution, Molecular * MeSH
- Models, Molecular MeSH
- Immunity, Innate genetics MeSH
- Birds genetics parasitology MeSH
- Sequence Analysis, DNA MeSH
- Selection, Genetic * genetics MeSH
- Static Electricity MeSH
- Toll-Like Receptor 4 chemistry genetics MeSH
- Protein Binding MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Names of Substances
- Glycolipids MeSH
- Ligands MeSH
- lipid A precursors, bacterial MeSH Browser
- Lipid A MeSH
- Lipopolysaccharides MeSH
- Lymphocyte Antigen 96 MeSH
- Toll-Like Receptor 4 MeSH
Positive selection acting on Toll-like receptors (TLRs) has been recently investigated to reveal evolutionary mechanisms of host-pathogen molecular co-adaptation. Much of this research, however, has focused mainly on the identification of sites predicted to be under positive selection, bringing little insight into the functional differences and similarities among species and a limited understanding of convergent evolution in the innate immune molecules. In this study, we provide evidence of phenotypic variability in the avian TLR4 ligand-binding region (LBR), the direct interface between host and pathogen molecular structures. We show that 55 passerine species vary substantially in the distribution of electrostatic potential on the surface of the receptor, and based on these distinct patterns, we identified four species clusters. Seven of the 34 evolutionarily nonconservative and positively selected residues correspond topologically to sites previously identified as being important for lipopolysaccharide, lipid IVa or MD-2 binding. Five of these positions codetermine the identity of the charge clusters. Groups of species that host-related communities of pathogens were predicted to cluster based on their TLR4 LBR charge. Despite some evidence for convergence among taxa, there were no clear associations between the TLR4 LBR charge distribution and any of the general ecological characteristics compared (migration, latitudinal distribution and diet). Closely related species, however, mostly belonged to the same surface charge cluster indicating that phylogenetic constraints are key determinants shaping TLR4 adaptive evolution. Our results suggest that host innate immune evolution is consistent with Fahrenholz's rule on the cospeciation of hosts and their parasites.
Department of Botany and Zoology Faculty of Science Masaryk University Brno Czech Republic
Department of Cell Biology Faculty of Science Charles University Prague Czech Republic
Department of Ecology Faculty of Science Charles University Prague Czech Republic
Department of Zoology Faculty of Science Charles University Prague Czech Republic
Institute of Vertebrate Biology The Czech Academy of Sciences Brno Czech Republic
References provided by Crossref.org
Understanding the evolution of immune genes in jawed vertebrates
Selection Balancing at Innate Immune Genes: Adaptive Polymorphism Maintenance in Toll-Like Receptors
Adaptation and Cryptic Pseudogenization in Penguin Toll-Like Receptors
GENBANK
AY064697.1, NM_021297.2, MG209180, MG209225, FJ695612
