The evolutionary dynamics of self-incompatibility systems.

Journal Article (Journal Article)

Self-incompatible flowering plants reject pollen that expresses the same mating specificity as the pistil (female reproductive tract). In most plant families, pollen and pistil mating specificities segregate as a single locus, the S locus. In at least two self-incompatibility systems, distinct pollen and pistil specificity genes are embedded in an extensive nonrecombining tract. To facilitate consideration of how new S locus specificities arise in systems with distinct pollen and pistil genes, we present a graphical model for the generation of hypotheses. It incorporates the evolutionary principle that nonreciprocal siring success (cross-pollinations between two plants produce seeds in only one direction) tends to favor the rejecting partner. This model suggests that selection within S-allele specificity classes could accelerate the rate of nonsynonymous (amino acid-changing) substitutions, with periodic selective sweeps removing segregating variation within classes. Accelerated substitution within specificity classes could also promote the origin of new S-allele specificities.

Full Text

Duke Authors

Cited Authors

  • Newbigin, E; Uyenoyama, MK

Published Date

  • September 2005

Published In

Volume / Issue

  • 21 / 9

Start / End Page

  • 500 - 505

PubMed ID

  • 16023253

International Standard Serial Number (ISSN)

  • 0168-9525

Digital Object Identifier (DOI)

  • 10.1016/j.tig.2005.07.003


  • eng