Self-recognition in social amoebae is mediated by allelic pairs of tiger genes

Science. 2011 Jul 22;333(6041):467-70. doi: 10.1126/science.1203903. Epub 2011 Jun 23.


Free-living cells of the social amoebae Dictyostelium discoideum can aggregate and develop into multicellular fruiting bodies in which many die altruistically as they become stalk cells that support the surviving spores. Dictyostelium cells exhibit kin discrimination--a potential defense against cheaters, which sporulate without contributing to the stalk. Kin discrimination depends on strain relatedness, and the polymorphic genes tgrB1 and tgrC1 are potential components of that mechanism. Here, we demonstrate a direct role for these genes in kin discrimination. We show that a matching pair of tgrB1 and tgrC1 alleles is necessary and sufficient for attractive self-recognition, which is mediated by differential cell-cell adhesion. We propose that TgrB1 and TgrC1 proteins mediate this adhesion through direct binding. This system is a genetically tractable ancient model of eukaryotic self-recognition.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Alleles
  • Amino Acid Sequence
  • Cell Adhesion*
  • Cell Aggregation
  • Dictyostelium / genetics*
  • Dictyostelium / physiology*
  • Gene Deletion
  • Genes, Protozoan*
  • Molecular Sequence Data
  • Protein Binding
  • Protozoan Proteins / metabolism*
  • Spores, Protozoan / physiology


  • Protozoan Proteins