Uniform ripening encodes a Golden 2-like transcription factor regulating tomato fruit chloroplast development

Science. 2012 Jun 29;336(6089):1711-5. doi: 10.1126/science.1222218.

Abstract

Modern tomato (Solanum lycopersicum) varieties are bred for uniform ripening (u) light green fruit phenotypes to facilitate harvests of evenly ripened fruit. U encodes a Golden 2-like (GLK) transcription factor, SlGLK2, which determines chlorophyll accumulation and distribution in developing fruit. In tomato, two GLKs--SlGLK1 and SlGLK2--are expressed in leaves, but only SlGLK2 is expressed in fruit. Expressing GLKs increased the chlorophyll content of fruit, whereas SlGLK2 suppression recapitulated the u mutant phenotype. GLK overexpression enhanced fruit photosynthesis gene expression and chloroplast development, leading to elevated carbohydrates and carotenoids in ripe fruit. SlGLK2 influences photosynthesis in developing fruit, contributing to mature fruit characteristics and suggesting that selection of u inadvertently compromised ripe fruit quality in exchange for desirable production traits.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Chloroplasts / genetics*
  • Chloroplasts / physiology
  • Chromosome Mapping
  • Chromosomes, Plant
  • Fruit / genetics
  • Fruit / growth & development
  • Phenotype
  • Plant Proteins / genetics*
  • Plant Proteins / physiology
  • Solanum lycopersicum / genetics*
  • Solanum lycopersicum / growth & development*
  • Transcription Factors / genetics*
  • Transcription Factors / physiology

Substances

  • Plant Proteins
  • Transcription Factors