Tracing back the nascence of a new sex-determination pathway to the ancestor of bees and ants.
In several Hymenoptera, sexual fate is determined by the allelic composition at the complementary sex-determiner locus, a sex-determination mechanism that can strongly affect population dynamics. To date, the molecular identification of complementary sex determiner has only been achieved in the honeybee, where the complementary sex-determiner gene was reported to have arisen from duplication of the feminizer gene. Strikingly, the complementary sex-determiner gene was also proposed to be unique to the honeybee lineage. Here we identify feminizer and complementary sex-determiner orthologues in bumble bees and ants. We further demonstrate that the duplication of feminizer that produced complementary sex determiner occurred before the divergence of Aculeata species (~120 Myr ago). Finally, we provide evidence that the two genes evolved concertedly through gene conversion, complementary sex-determiner evolution being additionally shaped by mosaic patterns of selection. Thus, the complementary sex-determiner gene likely represents the molecular basis for single locus-complementary sex determination in the Aculeata infra-order, and possibly, in the entire Hymenoptera order.
INRA, UMR 1355 Institut Sophia Agrobiotech, Evolution and Specificity of Multitrophic Interactions, Sophia Antipolis 06903, France.
Sandra
S
Schmieder
Dominique
D
Colinet
Marylène
M
Poirié
D000818:Animals; D001000:Ants / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D001516:Bees / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D019143:Evolution, Molecular; D005260:Female; D019476:Insect Proteins / Q000235:genetics / Q000378:metabolism; D008297:Male; D019849:Sex Determination Processes / Q000235:genetics / Q000502:physiology*
D019476:Insect Proteins