Parasite-mediated selection of major histocompatibility complex variability in wild brandt's voles (Lasiopodomys brandtii) from Inner Mongolia, China

被引:16
作者
Zhang, Min [1 ]
He, Hongxuan [1 ]
机构
[1] Chinese Acad Sci, Inst Zool, Key Lab Anim Ecol & Conservat Biol, Beijing 100101, Peoples R China
来源
BMC EVOLUTIONARY BIOLOGY | 2013年 / 13卷
关键词
Major histocompatibility complex; Genetic diversity; Parasite-driven selection; Fluctuating selection; Heterozygote advantage; Rare allele advantage; CLASS-II GENE; MHC DIVERSITY; POPULATION-STRUCTURE; BALANCING SELECTION; MULTIPLE PARASITES; NATURAL-SELECTION; SEASONAL-CHANGES; IMMUNE GENES; MOUSE LEMUR; SOAY SHEEP;
D O I
10.1186/1471-2148-13-149
中图分类号
Q [生物科学];
学科分类号
07 ; 0710 ; 09 ;
摘要
Background: Genes of the major histocompatibility complex (MHC) exhibit high levels of variability, which is believed to have arisen through pathogen-mediated selection. We investigated the relationship between parasite load and genetic diversity at selectively neutral, non-coding markers (microsatellites) and adaptive genetic variation at a functionally important part of the MHC in six independent natural populations of Brandt's voles (Lasiopodomys brandtii) from two regions of the Xilingol Grassland area of Inner Mongolia. Results: Two-hundred and fifty-two voles were screened for gastrointestinal parasites, and were assessed for genetic variation. Parasite screening was done through non-invasive fecal egg counts, while allelic diversity was determined via single-stranded conformation polymorphism and DNA sequencing. We detected eight distinct helminth egg morphotypes. A total of 10 microsatellite loci were genotyped and 19 unique MHC class II B alleles were isolated. The rate of nonsynonymous substitutions (d(N)) exceeded the rate of synonymous substitutions (d(S)) at putative antigen binding sites of DRB. Neutral and adaptive genetic diversity differed between the six vole populations. To test the main pathogen-driven selection hypotheses for the maintenance of host MHC diversity and parasite species-specific co-evolutionary effects, multivariate approaches (generalized linear mixed models) were used to test for associations between the MHC class II DRB genotype and infections with nematodes. We found no evidence for heterozygote advantage, and overall heterozygosity was lower than expected in the MHC alleles. We identified an association between the parasite load and specific MHC alleles in the voles, and this pattern varied between geographic regions. Conclusions: The results suggest that MHC variability in Brandt's voles is maintained by rare allele advantage and fluctuating selection, but the data failed to show any heterozygote advantage effect. Our results add to a growing body of evidence showing that the mode and relative strength of pathogen-driven selection acting on MHC diversity varies within specific wild populations. In addition, our study contributes to the understanding of what maintains MHC diversity, of host-pathogen coevolution and of how genetic diversity is maintained in voles.
引用
收藏
页数:14
相关论文
共 102 条
  • [1] The role of parasites in the dynamics of a reindeer population
    Albon, SD
    Stien, A
    Irvine, RJ
    Langvatn, R
    Ropstad, E
    Halvorsen, O
    [J]. PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES, 2002, 269 (1500) : 1625 - 1632
  • [2] Extensive polymorphism and geographical variation at a positively selected MHC class IIB gene of the lesser kestrel (Falco naumanni)
    Alcaide, Miguel
    Edwards, Scott V.
    Negro, Juan J.
    Serrano, David
    Tella, Jose L.
    [J]. MOLECULAR ECOLOGY, 2008, 17 (11) : 2652 - 2665
  • [3] On the relative roles of selection and genetic drift in shaping MHC variation
    Alcaide, Miguel
    [J]. MOLECULAR ECOLOGY, 2010, 19 (18) : 3842 - 3844
  • [4] RETRACTED: MHC diversity and differential exposure to pathogens in kestrels (Aves: Falconidae) (Retracted article. See vol. 22, pg. 1185, 2013)
    Alcaide, Miguel
    Lemus, Jesus A.
    Blanco, Guillermo
    Tella, Jose L.
    Serrano, David
    Negro, Juan J.
    Rodriguez, Airam
    Garcia-Montijano, Marino
    [J]. MOLECULAR ECOLOGY, 2010, 19 (04) : 691 - 705
  • [5] Anderson MJ, 2001, AUSTRAL ECOL, V26, P32, DOI 10.1111/j.1442-9993.2001.01070.pp.x
  • [6] Gene duplication, allelic diversity, selection processes and adaptive value of MHC class II DRB genes of the bank vole, Clethrionomys glareolus
    Axtner, Jan
    Sommer, Simone
    [J]. IMMUNOGENETICS, 2007, 59 (05) : 417 - 426
  • [7] New generation sequencers as a tool for genotyping of highly polymorphic multilocus MHC system
    Babik, Wieslaw
    Taberlet, Pierre
    Ejsmond, Maciej Jan
    Radwan, Jacek
    [J]. MOLECULAR ECOLOGY RESOURCES, 2009, 9 (03) : 713 - 719
  • [8] The impact of sex-role reversal on the diversity of the major histocompatibility complex: Insights from the seahorse (Hippocampus abdominalis)
    Bahr, Angela
    Wilson, Anthony B.
    [J]. BMC EVOLUTIONARY BIOLOGY, 2011, 11
  • [9] Helminth infections in Apodemus sylvaticus in southern England:: interactive effects of host age, sex and year on the prevalence and abundance of infections
    Behnke, JM
    Lewis, JW
    Zain, SNM
    Gilbert, FS
    [J]. JOURNAL OF HELMINTHOLOGY, 1999, 73 (01) : 31 - 44
  • [10] Benjamini Y, 2001, ANN STAT, V29, P1165