Light regulated modulation of Z-box containing promoters by photoreceptors and downstream regulatory components, COP1 and HY5, in Arabidopsis

Plant J. 2002 Sep;31(6):741-53. doi: 10.1046/j.1365-313x.2002.01395.x.


The Z-box is one of the light-responsive elements (LREs) found in the promoters of light inducible genes. We have studied the light responsive characteristics of Z-box containing synthetic as well as native promoters. We show that promoters with Z-box as a single LRE or paired with another LRE can respond to a broad spectrum of light. The response is primarily mediated by phyA, phyB and CRY1 photoreceptors at their respective wavelengths of light. We have demonstrated that CAB1 and Z-GATA containing promoters are down-regulated in hy5 mutants in the light. On the other hand, a promoter with Z-box alone is down-regulated in hy5 mutants both in dark and in light conditions, suggesting involvement of a similar regulatory system in the regulation of the promoter in two distinct developmental pathways: skotomorphogenesis and photomorphogenesis. Furthermore, similar to the CAB1 promoter, a Z-GATA containing promoter is derepressed in cop1 mutants in the dark. DNA-protein interaction studies reveal the presence of a DNA-binding activity that is specific to Z-box. These results provide insights into the regulation of the Z-box LRE mediated by various light signaling components.

Publication types

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

MeSH terms

  • Arabidopsis / genetics
  • Arabidopsis / physiology*
  • Arabidopsis / radiation effects
  • Arabidopsis Proteins*
  • Basic-Leucine Zipper Transcription Factors
  • Cryptochromes
  • DNA-Binding Proteins / genetics
  • Darkness
  • Drosophila Proteins*
  • Eye Proteins*
  • Flavoproteins / metabolism
  • Flavoproteins / radiation effects
  • Glucuronidase / genetics
  • Glucuronidase / metabolism
  • Light
  • Mutation
  • Nuclear Proteins / genetics
  • Nuclear Proteins / physiology*
  • Photoreceptor Cells*
  • Photoreceptor Cells, Invertebrate*
  • Photosynthetic Reaction Center Complex Proteins / genetics
  • Photosynthetic Reaction Center Complex Proteins / metabolism*
  • Photosynthetic Reaction Center Complex Proteins / radiation effects
  • Phytochrome / metabolism
  • Phytochrome / radiation effects
  • Phytochrome A
  • Phytochrome B
  • Promoter Regions, Genetic / genetics*
  • Receptors, G-Protein-Coupled
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / metabolism
  • Signal Transduction / physiology
  • Transcription Factors / genetics
  • Zinc Fingers / genetics*


  • Arabidopsis Proteins
  • Basic-Leucine Zipper Transcription Factors
  • CRY1 protein, Arabidopsis
  • Cryptochromes
  • DNA-Binding Proteins
  • Drosophila Proteins
  • Eye Proteins
  • Flavoproteins
  • HY5 protein, Arabidopsis
  • Nuclear Proteins
  • PHYA protein, Arabidopsis
  • PHYB protein, Arabidopsis
  • Photosynthetic Reaction Center Complex Proteins
  • Phytochrome A
  • Receptors, G-Protein-Coupled
  • Recombinant Fusion Proteins
  • Transcription Factors
  • cry protein, Drosophila
  • Phytochrome
  • Phytochrome B
  • Glucuronidase