Spatial pattern of adaptive and neutral genetic diversity across different biomes in the lesser anteater (Tamandua tetradactyla)

Ecology and Evolution

Camila L. Clozato¹  Camila J. Mazzoni²  Nadia Moraes-Barros¹  João S. Morgante¹ 

[1] Laboratório de Biologia Evolutiva e Conservação de Vertebrados, Departamento de Genética e Biologia Evolutiva, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brasil;Leibniz-Institute for Zoo and Wildlife Research (IZW), Evolutionary Genetics, Berlin, Germany

关键词: Brazil;    DRB;    major histocompatibility complex;    microsatellites;    next‐generation sequencing;    selection;    Tamandua tetradactyla;   

DOI  :  10.1002/ece3.1656

来源: Wiley

【 摘 要 】

Abstract

The genes of the major histocompatibility complex (MHC) code for proteins involved in antigen recognition and activation of the adaptive immune response and are thought to be regulated by natural selection, especially due to pathogen-driven selective pressure. In this study, we investigated the spatial distribution of MHC class II DRB exon 2 gene diversity of the lesser anteater (Tamandua tetradactyla) across five Brazilian biomes using next-generation sequencing and compared the MHC pattern with that of neutral markers (microsatellites). We found a noticeable high level of diversity in DRB (60 amino acid alleles in 65 individuals) and clear signatures of historical positive selection acting on this gene. Higher allelic richness and proportion of private alleles were found in rain forest biomes, especially Amazon forest, a megadiverse biome, possibly harboring greater pathogen richness as well. Neutral markers, however, showed a similar pattern to DRB, demonstrating the strength of demography as an additional force to pathogen-driven selection in shaping MHC diversity and structure. This is the first characterization and description of diversity of a MHC gene for any member of the magna-order Xenarthra, one of the basal lineages of placental mammals.

【 授权许可】

CC BY   
© 2015 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.

Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.