Positive selection of Toll-like receptor 2 polymorphisms in two closely related old world monkey species, rhesus and Japanese macaques

• Published in: Immunogenetics (New York) Vol. 64; no. 1; pp. 15 - 29
• Main Authors: Takaki, Akiko, Yamazaki, Akiko, Maekawa, Tomoyuki, Shibata, Hiroki, Hirayama, Kenji, Kimura, Akinori, Hirai, Hirohisa, Yasunami, Michio
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer-Verlag 01.01.2012; Springer Nature B.V
• Subjects: Alleles; Allergology; Amino Acid Sequence; Amino acids; Animals; Asparagine; Biomedical and Life Sciences; Biomedicine; Cell Biology; Codons; Consortia; Evolution; Evolution, Molecular; Exons; Gene Function; Genetic testing; Genomes; Gram-positive bacteria; Haplotypes; HEK293 Cells; Human Genetics; Humans; Immunology; Ligands; Macaca - genetics; Macaca fuscata; Macaca mulatta; Macaca mulatta - genetics; Molecular Sequence Data; Monkeys & apes; Nucleotide sequence; Nucleotides; Original Paper; Phylogeny; Polymorphism, Single Nucleotide; Positive selection; Research centers; Selection, Genetic; Sequence Alignment; Signal transduction; Single-nucleotide polymorphism; TLR2 protein; Toll-Like Receptor 2 - chemistry; Toll-Like Receptor 2 - genetics; Toll-like receptors; Tuberculosis; Tyrosine; Japan; Reporter gene assay; Molecular evolution; Innate immunity; TLR; Nonhuman primate; Polymorphism
• ISSN: 0093-7711; 1432-1211
• DOI: 10.1007/s00251-011-0556-2

Toll-like receptor 2 (TLR2) plays an important role in the recognition of a variety of pathogenic microbes. In the present study, we compared polymorphisms of TLR2 locus in two closely related old world monkey species, rhesus monkey ( Macaca mulatta ) and Japanese monkey ( Macaca fuscata ). By nucleotide sequencing of the third exon of TLR2 gene from 21 to 35 respective individuals, we could assign 17 haplotype combinations of 17 coding SNPs of ten non-synonymous and seven synonymous substitutions. A non-synonymous substitution at codon position 326 appeared to be differentially fixed in each species, asparagine for M. mulatta whereas tyrosine for M. fuscata , and may contribute to certain functional properties because it locates in the region contributing to ligand binding and interaction with dimerization partner of TLR2-TLR1 heterodimeric complex. Although TLR2 alleles have diverged to similar extent in both species, they have evolved in significantly different ways; TLR2 of M. fuscata has undergone purifying selection while the membrane-proximal part of the extracellular domain of M. mulatta TLR2 exhibits higher rates of non-synonymous substitutions, indicating a trace of Darwinian positive selection.