Red Queen revisited: Immune gene diversity and parasite load in the asexual Poecilia formosa versus its sexual host species P. mexicana

PLoS One. 2019 Jul 3;14(7):e0219000. doi: 10.1371/journal.pone.0219000. eCollection 2019.

Abstract

In accordance with the Red Queen hypothesis, the lower genotypic diversity in clonally reproducing species should make them easier targets for pathogen infection, especially when closely related sexually reproducing species occur in close proximity. We analyzed two populations of clonal P. formosa and their sexual parental species P. mexicana by correlating individual parasite infection with overall and immune genotype. Our study revealed lower levels of overall genotypic diversity and marginally fewer MHC class I alleles in P. formosa individuals compared to sexually reproducing P. mexicana. Parasite load, however, differed only between field sites but not between species. We hypothesize that this might be due to slightly higher genotypic diversity in P. formosa at the innate immune system (toll like receptor 8) which is likely due to the species' hybrid origin. In consequence, it appears that clonal individuals do not necessarily suffer a disadvantage compared to sexual individuals when fighting parasite infection.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptive Immunity / genetics
  • Alleles
  • Animals
  • Female
  • Fish Proteins / genetics
  • Fish Proteins / immunology
  • Genes, MHC Class I
  • Genetic Variation
  • Genotype
  • Host Specificity / genetics
  • Host Specificity / immunology
  • Immunity, Innate / genetics
  • Male
  • Mexico
  • Models, Genetic
  • Models, Immunological
  • Parasite Load
  • Poecilia / genetics
  • Poecilia / parasitology*
  • Poecilia / physiology*
  • Reproduction / genetics
  • Reproduction / immunology
  • Reproduction, Asexual / genetics*
  • Reproduction, Asexual / immunology*
  • Species Specificity
  • Toll-Like Receptor 8 / genetics
  • Toll-Like Receptor 8 / immunology

Substances

  • Fish Proteins
  • Toll-Like Receptor 8

Grants and funding

This work was supported by grants to MS (German Research Foundation DFG projects SFB 567 ‘Mechanismen der interspezifischen Interaktion von Organismen,’ Scha408/10-1 and Scha408/12-1), the University of Bochum, the University of Cologne and the University of Würzburg. We acknowledge support by the DFG Open Access Publication Funds of the Ruhr-Universität Bochum. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.