Spatial pattern of genetic diversity and selection in the MHC class II DRB of three Neotropical bat species. Issue 1 (December 2016)

• Record Type: Journal Article
• Authors: Salmier, Arielle; de Thoisy, Benoit; Crouau-Roy, Brigitte; Lacoste, Vincent; Lavergne, Anne
• Is Part Of: BMC evolutionary biology. Volume 16:Issue 1(2016)
• Page Start: 1
• Page End: 19
• Publication Date: 2016-12
• Subjects: MHC -- DRB polymorphism -- Selection -- Carollia perspicillata -- Desmodus rotundus -- Molossus molossus; Evolution (Biology) -- Periodicals; 576.805
• DOI: 10.1186/s12862-016-0802-1
• Languages: English
• ISSNs: 1471-2148

Abstract

Abstract Background Although bats are natural reservoirs of many pathogens, few studies have been conducted on the genetic variation and detection of selection in major histocompatibility complex (MHC) genes. These genes are critical for resistance and susceptibility to diseases, and host–pathogen interactions are major determinants of their extensive polymorphism. Here we examined spatial patterns of diversity of the expressed MHC class IIDRB gene of three sympatric Neotropical bats, Carollia perspicillata andDesmodus rotundus (Phyllostomidae), andMolossus molossus (Molossidae), all of which use the same environments (e.g., forests, edge habitats, urban areas). Comparison with neutral marker (mtDNA D-loop) diversity was performed at the same time. Results Twenty-threeDRB alleles were identified in 19C. perspicillata, 30 alleles in 35D. rotundus and 20 alleles in 28 M. molossus . The occurrence of multipleDRB loci was found for the two Phyllostomidae species. TheDRB polymorphism was high in all sampling sites and different signatures of positive selection were detected depending on the environment. The patterns ofDRB diversity were similar to those of neutral markers forC. perspicillata andM. molossus. In contrast, these patterns were different forD. rotundus for which a geographical structure was highlighted. A heterozygote advantage was also identified for this species. No recombination or gene conversion event was found and phylogenetic relationships showed a trans-species mode of evolution in the Phyllostomids. Conclusions This study of MHC diversity demonstrated the strength of the environment and contrasting pathogen pressures in shapingDRB diversity. Differences between positively selected sites identified in bat species highlighted the potential role of gut microbiota in shaping immune responses. Furthermore, multiple geographic origins and/or population admixtures observed inC. perspicillata andM. molossus populations acted as an additional force in shapingDRB diversity. In contrast, DRB diversity ofD. rotundus was shaped by environment rather than demographic history.