The evolution of male-female sexual dimorphism predates the gender-based divergence of the mating locus gene MAT3/RB

Mol Biol Evol. 2013 May;30(5):1038-40. doi: 10.1093/molbev/mst018. Epub 2013 Jan 30.


The molecular bases for the evolution of male-female sexual dimorphism are possible to study in volvocine algae because they encompass the entire range of reproductive morphologies from isogamy to oogamy. In 1978, Charlesworth suggested the model of a gamete size gene becoming linked to the sex-determining or mating type locus (MT) as a mechanism for the evolution of anisogamy. Here, we carried out the first comprehensive study of a candidate MT-linked oogamy gene, MAT3/RB, across the volvocine lineage. We found that evolution of anisogamy/oogamy predates the extremely high male-female divergence of MAT3 that characterizes the Volvox carteri lineage. These data demonstrate very little sex-linked sequence divergence of MAT3 between the two sexes in other volvocine groups, though linkage between MAT3 and the mating locus appears to be conserved. These data implicate genetic determinants other than or in addition to MAT3 in the evolution of anisogamy in volvocine algae.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biological Evolution
  • Chlamydomonas / classification
  • Chlamydomonas / genetics*
  • Molecular Sequence Data
  • Phylogeny
  • Plant Proteins / classification
  • Plant Proteins / genetics
  • Volvox / classification
  • Volvox / genetics*


  • Plant Proteins

Associated data

  • GENBANK/AB771928
  • GENBANK/AB771929
  • GENBANK/AB771930
  • GENBANK/AB771931
  • GENBANK/AB771932
  • GENBANK/AB771933
  • GENBANK/AB771934
  • GENBANK/AB771935
  • GENBANK/AB771936
  • GENBANK/AB771937
  • GENBANK/AB771938
  • GENBANK/AB771939
  • GENBANK/AB771940
  • GENBANK/AB771941
  • GENBANK/AB771942
  • GENBANK/AB771943
  • GENBANK/AB771944
  • GENBANK/AB771945
  • GENBANK/AB771946
  • GENBANK/AB771947
  • GENBANK/AB771948
  • GENBANK/AB771949
  • GENBANK/AB771950
  • GENBANK/AB771951
  • GENBANK/AB771952
  • GENBANK/AB771953
  • GENBANK/AB771954