A naturally occurring epigenetic mutation in a gene encoding an SBP-box transcription factor inhibits tomato fruit ripening

Nat Genet. 2006 Aug;38(8):948-52. doi: 10.1038/ng1841. Epub 2006 Jul 9.

Abstract

A major component in the regulatory network controlling fruit ripening is likely to be the gene at the tomato Colorless non-ripening (Cnr) locus. The Cnr mutation results in colorless fruits with a substantial loss of cell-to-cell adhesion. The nature of the mutation and the identity of the Cnr gene were previously unknown. Using positional cloning and virus-induced gene silencing, here we demonstrate that an SBP-box (SQUAMOSA promoter binding protein-like) gene resides at the Cnr locus. Furthermore, the Cnr phenotype results from a spontaneous epigenetic change in the SBP-box promoter. The discovery that Cnr is an epimutation was unexpected, as very few spontaneous epimutations have been described in plants. This study demonstrates that an SBP-box gene is critical for normal ripening and highlights the likely importance of epialleles in plant development and the generation of natural variation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Base Sequence
  • DNA, Plant / genetics
  • Epigenesis, Genetic
  • Fruit / genetics
  • Fruit / growth & development
  • Gene Expression
  • Genes, Plant*
  • Molecular Sequence Data
  • Mutation
  • Phenotype
  • Plant Proteins / genetics*
  • Solanum lycopersicum / genetics*
  • Solanum lycopersicum / growth & development*
  • Transcription Factors / genetics*

Substances

  • DNA, Plant
  • Plant Proteins
  • Transcription Factors

Associated data

  • GENBANK/DQ672601