title: Self-recognition in social amoebae is mediated by allelic pairs of tiger genes.
abstract: 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.
authors.affiliation: Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX 77030, USA.
authors.forename: Shigenori
authors.initials: S
authors.lastname: Hirose
authors.forename: Rocio
authors.initials: R
authors.lastname: Benabentos
authors.forename: Hsing-I
authors.initials: HI
authors.lastname: Ho
authors.forename: Adam
authors.initials: A
authors.lastname: Kuspa
authors.forename: Gad
authors.initials: G
authors.lastname: Shaulsky
mesh_terms: D000483:Alleles; D000595:Amino Acid Sequence; D002448:Cell Adhesion; D002449:Cell Aggregation; D004023:Dictyostelium / Q000235:genetics* / Q000502:physiology*; D017353:Gene Deletion; D017125:Genes, Protozoan; D008969:Molecular Sequence Data; D011485:Protein Binding; D015800:Protozoan Proteins / Q000378:metabolism*; D033761:Spores, Protozoan / Q000502:physiology
chemical_list: D015800:Protozoan Proteins