The molecular basis of sex: linking yeast to human

Mol Biol Evol. 2011 Jul;28(7):1963-6. doi: 10.1093/molbev/msr026. Epub 2011 Jan 31.


Species-specific recognition between egg and sperm, a crucial event that marks the beginning of fertilization in multicellular organisms, mirrors the binding between haploid cells of opposite mating type in unicellular eukaryotes such as yeast. However, as implied by the lack of sequence similarity between sperm-binding regions of invertebrate and vertebrate egg coat proteins, these interactions are thought to rely on completely different molecular entities. Here, we argue that these recognition systems are, in fact, related: despite being separated by 0.6-1 billion years of evolution, functionally essential domains of a mollusc sperm receptor and a yeast mating protein adopt the same 3D fold as egg zona pellucida proteins mediating the binding between gametes in humans.

Publication types

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

MeSH terms

  • Animals
  • Egg Proteins / chemistry
  • Evolution, Molecular
  • Genes, Mating Type, Fungal
  • Humans
  • Models, Molecular
  • Mollusca
  • Protein Conformation
  • Species Specificity
  • Sperm-Ovum Interactions / physiology*
  • Zona Pellucida / chemistry


  • Egg Proteins