De-etiolated 1 and damaged DNA binding protein 1 interact to regulate Arabidopsis photomorphogenesis

Curr Biol. 2002 Sep 3;12(17):1462-72. doi: 10.1016/s0960-9822(02)01106-5.


Background: Plant development is exquisitely sensitive to light. Seedlings grown in the dark have a developmentally arrested etiolated phenotype, whereas in the light they develop leaves and complete their life cycle. Arabidopsis de-etiolated 1 (det1) mutants develop like light-grown seedlings even when grown in the dark. DET1 encodes a nuclear protein that appears to act downstream from multiple photoreceptors to regulate morphogenesis and gene expression in response to light. However, its function has remained unknown.

Results: We used microarrays to examine defects in transcription in dark-grown det1 seedlings. We found extensive changes in gene expression, including many of the transcriptional responses observed in light-treated wild-type seedlings. We used an epitope-tagging approach to determine the basis of DET1 function. GFP-DET1 rescues the det1 phenotype, is localized to the nucleus, and forms an approximately 350 kDa complex, which is required for full DET1 activity. We affinity-purified the DET1 complex and identified an approximately 120 kDa copurifying protein that is the plant homolog of UV-Damaged DNA Binding Protein 1 (DDB1), a protein implicated in the human disease xeroderma pigmentosa. A null mutation in Arabidopsis DDB1A results in no obvious phenotype on its own, yet it enhances the phenotype of a weak det1 allele.

Conclusions: DET1 and DDB1 interact both biochemically and genetically. In animal cells, DDB1 interacts with histone acetyltransferase complexes. The DET1/DDB1 complex may regulate gene expression in response to light via recruitment of HAT activity. Thus, DET1, whose sequence is conserved in both animals and plants, may play a direct role in the regulation of many genes.

Publication types

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

MeSH terms

  • Acetyltransferases / physiology
  • Active Transport, Cell Nucleus
  • Amino Acid Sequence
  • Animal Population Groups / genetics
  • Animals
  • Arabidopsis / genetics
  • Arabidopsis / physiology*
  • Arabidopsis / radiation effects
  • Arabidopsis Proteins / genetics
  • Arabidopsis Proteins / physiology*
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / physiology*
  • Darkness
  • Epistasis, Genetic*
  • Epitopes
  • Gene Expression Profiling
  • Gene Expression Regulation, Plant / radiation effects*
  • Histone Acetyltransferases
  • Intracellular Signaling Peptides and Proteins
  • Macromolecular Substances
  • Models, Biological
  • Molecular Sequence Data
  • Morphogenesis / genetics
  • Morphogenesis / radiation effects
  • Nuclear Proteins / genetics
  • Nuclear Proteins / physiology*
  • Oligonucleotide Array Sequence Analysis
  • Phenotype
  • Protein Interaction Mapping
  • Recombinant Fusion Proteins / physiology
  • Saccharomyces cerevisiae Proteins / physiology
  • Seedlings / physiology
  • Seedlings / radiation effects
  • Sequence Alignment
  • Sequence Homology, Amino Acid
  • Transcription, Genetic / genetics
  • Transcription, Genetic / radiation effects


  • Arabidopsis Proteins
  • DET1 protein, Arabidopsis
  • DNA-Binding Proteins
  • Epitopes
  • Intracellular Signaling Peptides and Proteins
  • Macromolecular Substances
  • Nuclear Proteins
  • Recombinant Fusion Proteins
  • Saccharomyces cerevisiae Proteins
  • Acetyltransferases
  • Histone Acetyltransferases