Light regulated modulation of Z-box containing promoters by photoreceptors and downstream regulatory components, COP1 and HY5, in Arabidopsis.
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.
Yadav
Vandana
V
National Center for Plant Genome Research, JNU Campus, New Delhi 110067, India.
Kundu
Snehangshu
S
Chattopadhyay
Debasis
D
Negi
Prem
P
Wei
Ning
N
Deng
Xing-Wang
XW
Chattopadhyay
Sudip
S
D017360:Arabidopsis / Q000235:genetics / Q000502:physiology* / Q000528:radiation effects; D029681:Arabidopsis Proteins; D050976:Basic-Leucine Zipper Transcription Factors; D056931:Cryptochromes; D004268:DNA-Binding Proteins / Q000235:genetics; D003624:Darkness; D029721:Drosophila Proteins; D005136:Eye Proteins; D005420:Flavoproteins / Q000378:metabolism / Q000528:radiation effects; D005966:Glucuronidase / Q000235:genetics / Q000378:metabolism; D008027:Light; D009154:Mutation; D009687:Nuclear Proteins / Q000235:genetics / Q000502:physiology*; D010786:Photoreceptor Cells; D017956:Photoreceptor Cells, Invertebrate; D045322:Photosynthetic Reaction Center Complex Proteins / Q000235:genetics / Q000378:metabolism* / Q000528:radiation effects; D010834:Phytochrome / Q000378:metabolism / Q000528:radiation effects; D051942:Phytochrome A; D051939:Phytochrome B; D011401:Promoter Regions, Genetic / Q000235:genetics*; D043562:Receptors, G-Protein-Coupled; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology; D014157:Transcription Factors / Q000235:genetics; D016335:Zinc Fingers / Q000235:genetics*
D029681:Arabidopsis Proteins; D050976:Basic-Leucine Zipper Transcription Factors; C538962:CRY1 protein, Arabidopsis; D056931:Cryptochromes; D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D005136:Eye Proteins; D005420:Flavoproteins; C109254:HY5 protein, Arabidopsis; D009687:Nuclear Proteins; C497973:PHYA protein, Arabidopsis; C497952:PHYB protein, Arabidopsis; D045322:Photosynthetic Reaction Center Complex Proteins; D051942:Phytochrome A; D043562:Receptors, G-Protein-Coupled; D011993:Recombinant Fusion Proteins; D014157:Transcription Factors; C119828:cry protein, Drosophila; D010834:Phytochrome; D051939:Phytochrome B; D005966:Glucuronidase