Ancient asymmetries in the evolution of flowers

Curr Biol. 2001 Jul 10;11(13):1050-2. doi: 10.1016/s0960-9822(01)00295-0.


Dorsoventral asymmetry in flowers is thought to have evolved many times independently as a specialized adaptation to animal pollinators. To understand how such a complex trait could have arisen repeatedly, we have compared the expression of a gene controlling dorsoventral asymmetry in Antirrhinum with its counterpart in Arabidopsis, a distantly related species with radially symmetrical flowers. We found that the Arabidopsis gene is expressed asymmetrically in floral meristems, even though they are destined to form symmetrical flowers. This suggests that, although the flowers of the common ancestor were probably radially symmetrical, they may have had an incipient asymmetry, evident at the level of early gene activity, which could have been recruited many times during evolution to generate asymmetric flowers.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Arabidopsis / genetics*
  • Arabidopsis / growth & development*
  • Biological Evolution*
  • DNA-Binding Proteins
  • Gene Expression Regulation, Plant
  • Plant Proteins / biosynthesis
  • Plant Proteins / genetics
  • RNA, Plant / biosynthesis
  • Transcription Factors


  • DNA-Binding Proteins
  • Plant Proteins
  • RNA, Plant
  • Transcription Factors
  • cycloidea protein, Antirrhinum