Mutations in the DET1 gene affect cell-type-specific expression of light-regulated genes and chloroplast development in Arabidopsis

Proc Natl Acad Sci U S A. 1990 Nov;87(22):8776-80. doi: 10.1073/pnas.87.22.8776.


When grown in the absence of light, the det1 mutant of Arabidopsis thaliana develops characteristics of a light-grown plant by morphological, cellular, and molecular criteria. Here, we show that recessive mutations at the DET1 locus also result in cell-type inappropriate accumulation of RNAs for light-regulated nuclear and chloroplast genes. det1 root plastids are differentiated into chloroplasts and are present in very high numbers in root cortex cells in contrast to the few starch-containing amyloplasts normally found in Arabidopsis roots. To assay the effect of the det1 mutation on the expression of photoregulated promoters, we used fusion constructs to stably transform wild-type and det1 mutants. We show that the three red-light-regulated chlorophyll a/b binding protein promoters are inappropriately expressed in the roots of det1 seedlings and the blue-light-controlled anthocyanin biosynthetic gene, chalcone synthase, is expressed ectopically in leaf mesophyll cells. These results, together with out previous findings, suggest that the DET1 gene product is a negatively acting regulatory molecule that is used in common by the light stimulus transduction pathway and by temporal or spatial regulatory signals in plants.

MeSH terms

  • Blotting, Northern
  • Chloroplasts / physiology*
  • Chloroplasts / ultrastructure
  • Cloning, Molecular
  • Gene Expression Regulation*
  • Light
  • Microscopy, Electron
  • Plants / genetics*
  • Promoter Regions, Genetic
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Signal Transduction


  • RNA, Messenger