Independent control by each female gamete prevents the attraction of multiple pollen tubes

Dev Cell. 2013 May 13;25(3):317-23. doi: 10.1016/j.devcel.2013.03.013.

Abstract

In flowering plants, double fertilization is normally accomplished by the first pollen tube, with the fertilized ovule subsequently inhibiting the attraction of a second pollen tube. However, the mechanism of second-pollen-tube avoidance remains unknown. We discovered that failure to fertilize either the egg cell or the central cell compromised second-pollen-tube avoidance in Arabidopsis thaliana. A similar disturbance was caused by disrupting the fertilization-independent seed (FIS) class polycomb-repressive complex 2 (FIS-PRC2), a central cell- and endosperm-specific chromatin-modifying complex for gene silencing. Therefore, the two female gametes have evolved their own signaling pathways. Intriguingly, second-pollen-tube attraction induced by half-successful fertilization allowed the ovules to complete double fertilization, producing a genetically distinct embryo and endosperm. We thus propose that each female gamete independently determines second-pollen-tube avoidance to maximize reproductive fitness in flowering plants.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aniline Compounds / metabolism
  • Arabidopsis / cytology
  • Arabidopsis / metabolism
  • Arabidopsis Proteins / genetics
  • Arabidopsis Proteins / metabolism*
  • Biological Evolution
  • Cell Death
  • Chromatin Assembly and Disassembly
  • Fertilization*
  • Fluorescence
  • Gene Silencing
  • Genetic Fitness
  • Ovule / cytology
  • Ovule / metabolism*
  • Pollen Tube / cytology
  • Pollen Tube / metabolism*
  • Pollination
  • Repressor Proteins / genetics
  • Repressor Proteins / metabolism*
  • Signal Transduction
  • Transcription Factors / genetics
  • Transcription Factors / metabolism

Substances

  • Aniline Compounds
  • Arabidopsis Proteins
  • FIS2 protein, Arabidopsis
  • PRC2 protein, Arabidopsis
  • Repressor Proteins
  • Transcription Factors
  • aniline blue