Termination of Stem Cell Maintenance in Arabidopsis Floral Meristems by Interactions Between WUSCHEL and AGAMOUS

Cell. 2001 Jun 15;105(6):805-14. doi: 10.1016/s0092-8674(01)00390-7.

Abstract

Floral meristems and shoot apical meristems (SAMs) are homologous, self-maintaining stem cell systems. Unlike SAMs, floral meristems are determinate, and stem cell maintenance is abolished once all floral organs are initiated. To investigate the underlying regulatory mechanisms, we analyzed the interactions between WUSCHEL (WUS), which specifies stem cell identity, and AGAMOUS (AG), which is required for floral determinacy. Our results show that repression of WUS by AG is essential for terminating the floral meristem and that WUS can induce AG expression in developing flowers. Together, this suggests that floral determinacy depends on a negative autoregulatory mechanism involving WUS and AG, which terminates stem cell maintenance.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • AGAMOUS Protein, Arabidopsis
  • Arabidopsis / cytology
  • Arabidopsis / genetics
  • Arabidopsis / physiology*
  • Arabidopsis Proteins*
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / metabolism*
  • Gene Expression Regulation, Plant
  • Homeodomain Proteins / genetics
  • Homeodomain Proteins / metabolism*
  • In Situ Hybridization
  • Meristem / cytology
  • Meristem / physiology*
  • Phenotype
  • Plant Proteins / genetics
  • Plant Proteins / metabolism*
  • Plant Structures / physiology*
  • Plant Structures / ultrastructure
  • Stem Cells / cytology
  • Stem Cells / physiology*
  • Transcription Factors*

Substances

  • AGAMOUS Protein, Arabidopsis
  • Arabidopsis Proteins
  • DNA-Binding Proteins
  • Homeodomain Proteins
  • LFY protein, Arabidopsis
  • Plant Proteins
  • Transcription Factors
  • WUSCHEL protein, Arabidopsis