Immunogenetics

, Volume 64, Issue 5, pp 379–388

The RIPK2 gene: a positional candidate for tick burden supported by genetic associations in cattle and immunological response of knockout mouse

  • Laercio R. Porto Neto
  • Nicholas N. Jonsson
  • Aaron Ingham
  • Rowan J. Bunch
  • Blair E. Harrison
  • William Barendse
  • Cooperative Research Centre for Beef Genetic Technologies
Original Paper

DOI: 10.1007/s00251-012-0601-9

Cite this article as:
Porto Neto, L.R., Jonsson, N.N., Ingham, A. et al. Immunogenetics (2012) 64: 379. doi:10.1007/s00251-012-0601-9

Abstract

Ticks and tick-borne diseases have a detrimental impact on livestock production causing estimated losses of around $200 million per year in Australia alone. Host resistance to ticks is heritable, within-breed heritability estimates being around 0.35, and with large differences between breeds. Previously a QTL for tick burden was detected on BTA14 at ~72 Mb distal to the centromere, near the gene receptor-interacting serine-threonine kinase 2 (RIPK2). To identify polymorphisms in this region, we sequenced all exons of the RIPK2 gene, identifying 46 single nucleotide polymorphism (SNP). Using SNP from RIPK2 as well as SNP from the bovine genome sequence, we genotyped two samples, one of 1,122 taurine dairy cattle and one of 761 zebu and zebu composite beef cattle. We confirmed that SNP and haplotypes from this region, including from RIPK2, were associated with tick burden in both dairy and beef cattle. To determine whether RIPK2 influences response to tick salivary gland extract (SGE), an immunisation experiment with tick SGE in a RIPK2 knockout (RIPK2 −/−) mouse strain was conducted. There was a significant (P < 0.05) reduction in IgG production in the RIPK2 −/− mouse in response to the SGE compared to its background strain C57BL/6 as well as the outbred CD1 mouse strain. In addition, antibodies generated by RIPK2 −/− mice recognised a different set of antigens within SGE when compared to parental-derived antibodies. In summary, the SNP association with tick burden at BTA14 was confirmed and quantitative and qualitative differences in antibody production were observed between RIPK2 −/− and wild-type mice.

Keywords

Rhipicephalus (Boophilus) microplusGene mappingMouse knockoutParasiteQTLTick

Supplementary material

251_2012_601_MOESM1_ESM.docx (107 kb)
ESM 1(DOCX 106 kb)

Copyright information

© Springer-Verlag 2012

Authors and Affiliations

  • Laercio R. Porto Neto
    • 1
    • 2
    • 3
  • Nicholas N. Jonsson
    • 3
    • 4
  • Aaron Ingham
    • 1
  • Rowan J. Bunch
    • 1
  • Blair E. Harrison
    • 1
  • William Barendse
    • 1
  • Cooperative Research Centre for Beef Genetic Technologies
  1. 1.CSIRO Livestock IndustriesQueensland Bioscience PrecinctSt LuciaAustralia
  2. 2.School of Agriculture and Food SciencesUniversity of QueenslandGattonAustralia
  3. 3.School of Veterinary ScienceUniversity of QueenslandGattonAustralia
  4. 4.College of Medical, Veterinary and Life SciencesUniversity of GlasgowGlasgowUK