Plant Molecular Biology

, Volume 61, Issue 1–2, pp 283–296 | Cite as

KIDARI, Encoding a Non-DNA Binding bHLH Protein, Represses Light Signal Transduction in Arabidopsis thaliana



Through activation tagging mutagenesis, we isolated a kidari-D (kdr-D) mutant, which exhibited a defect in blue and far-red light mediated photomorphogenesis. Under continuous blue light, the kdr-D mutant showed long hypocotyl phenotype, whereas it showed normal cotyledon opening and expansion. In addition, the kdr-D showed slightly longer hypocotyl under continuous far-red light, suggesting that KDR functions in a branch of cry signaling and mediates a cross-talk between cry and phyA. In the kdr-D mutant, a gene encoding a putative basic/Helix-Loop-Helix (bHLH) protein was overexpressed by the insertion of 35S enhancer into 10 kb upstream of the gene. Consistently, overexpression of this gene recapitulated the phenotype of kdr-D. KDR is composed of 94 amino acids with non-DNA binding HLH domain, a structure found in human Inhibitor of DNA binding 1 (Id-1) which functions as a negative regulator of bHLH proteins through heterodimerization with them. The KDR specifically interacted with HFR1, a bHLH protein regulating photomorphogenesis, in yeast two hybrid assay and the kdr-D was epistatic to 35S::HFR1 in the hypocotyl phenotype. Thus, it shows that KDR functions as a negative regulator of HFR1, similar to Id-1 in human. The KDR exhibited circadian expression pattern with an increase during the day. Taken together, our results suggest that KDR attenuates light mediated responses in day light condition through inhibition of the activity of bHLH proteins involved in light signaling.


bHLH cryptochrome light signaling non-DNA binding photomorphogenesis 


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  1. Ahmad, M., Cashmore, A.R. 1993HY4 gene of A. thaliana encodes a protein with characteristics of a blue-light photoreceptorNature366162166PubMedCrossRefGoogle Scholar
  2. Ahmad, M., Jarillo, J.A., Smirnova, O., Cashmore, A.R. 1998The CRY1 blue light photoreceptor of Arabidopsis interacts with phytochrome A in vitroMol. Cell1939948PubMedCrossRefGoogle Scholar
  3. Casal, J.J. 2000Phytochromes, cryptochromes, phototropin: photoreceptor interactions in plantsPhotochem. Photobiol.71111PubMedCrossRefGoogle Scholar
  4. Cashmore, A.R., Jarillo, J.A., Wu, Y.J., Liu, D. 1999Cryptochromes: blue light receptors for plants and animalsScience284760765PubMedCrossRefGoogle Scholar
  5. Chen, M., Chory, J., Fankhauser, C. 2004Light signal transduction in higher plantsAnnu. Rev. Genet.3887117PubMedCrossRefGoogle Scholar
  6. Clough, S.J., Bent, A.F. 1998Floral dip: a simplified method for Agrobacterium-mediated transformation of Arabidopsis thalianaPlant J.16735743PubMedCrossRefGoogle Scholar
  7. Duek, P.D., Fankhauser, C. 2003HFR1, a putative bHLH transcription factor, mediates both phytochrome A and cryptochrome signalingPlant J.34827836PubMedCrossRefGoogle Scholar
  8. Fairchild, C.D., Schumaker, M.A., Quail, P.H. 2000HFR1 encodes an atypical bHLH protein that acts in phytochrome A signal transductionGenes Dev.1423772391PubMedGoogle Scholar
  9. Fankhauser, C., Chory, J. 1997Light control of plant developmentAnnu. Rev. Cell Dev. Biol.13203229PubMedCrossRefGoogle Scholar
  10. Fankhauser, C., Chory, J. 2000RSF1, an Arabidopsis locus implicated in phytochrome A signalingPlant Physiol.1243945PubMedCrossRefGoogle Scholar
  11. Franklin, K.A., Whitelam, G.C. 2004Light signals, phytochromes and cross-talk with other environmental cuesJ. Exp. Bot.55271276PubMedCrossRefGoogle Scholar
  12. Furuya, M. 1993Phytochromes – their molecular species, gene families, and functionsAnnu. Rev. Plant Physiol. Plant Mol. Biol.44617645CrossRefGoogle Scholar
  13. Fujimori, T., Yamashino, T., Kato, T., Mizuno, T. 2004Circadian-controlled basic/helix-loop-helix factor, PIL6, implicated in light-signal trasduction in Arabidopsis thalianaPlant Cell Physiol.4510781086PubMedCrossRefGoogle Scholar
  14. Guo, H., Yang, H., Mockler, T.C., Lin, C. 1998Regulation of flowering time by Arabidopsis photoreceptorsScience27913601363PubMedCrossRefGoogle Scholar
  15. Guo, H., Duong, H., Ma, N., Lin, C. 1999The Arabidopsis blue light receptor cryptochrome 2 is a nuclear protein regulated by a blue light-dependent post-transcriptional mechanismPlant J.19279287PubMedCrossRefGoogle Scholar
  16. Guo, H., Mockler, T., Duong, H., Lin, C. 2001SUB1, an Arabidopsis Ca2+-binding protein involved in cryptochrome and phytochrome coactionScience291487490PubMedCrossRefGoogle Scholar
  17. Huala, E., Oeller, P.W., Liscum, E., Han, I.S., Larsen, E., Briggs, W.R. 1997Arabidopsis NPH1: a protein kinase with a putative redox-sensing domainScience27821202123PubMedCrossRefGoogle Scholar
  18. Huq, E., Al-Sady, B., Hudson, M.E., Kim, C., Apel, K., Quail, P.H. 2004Phyochrome-interacting factor 1 is a critical bHLH regulator of chlorophyll biosynthesisScience30519371941PubMedCrossRefGoogle Scholar
  19. Huq, E., Quail, P.H. 2002PIF4, a phytochrome-interacting bHLH factor, functions as a negative regulator of phytochrome B signaling pathwayEMBO J.2124412450PubMedCrossRefGoogle Scholar
  20. Jarillo, J.A., Capel, J., Tang, R.H., Yang, H.Q., Alonso, J.M., Ecker, J.R., Cashmore, A.R. 2001An Arabidopsis circadian clock component interacts with both CRY1 and phyBNature410487490PubMedCrossRefGoogle Scholar
  21. Jiao, Y., Yang, H., Ma, L., Sun, N., Yu, H., Liu, T., Gao, Y., Gu, H., Chen, Z., Wada, M., Gerstein, M., Zhao, H., Qu, L.J., Deng, X.W. 2003A genome-wide analysis of blue-light regulation of Arabidopsis transcription factor gene expression during seedling developmentPlant Physiol.13314801493PubMedCrossRefGoogle Scholar
  22. Kendrick, R.E., Kronenberg, G.H.M. 1994Photomorphogenesis in Plants2Kluwer Academic PublishersDordrechtGoogle Scholar
  23. Khanna, R., Huq, E., Kikis, E.A., Al-Sady, B., Lanzatella, C., Quail, P.H. 2004A novel molecular recognition motif necessary for targeting photoactivated phytochrome signaling to specific basic helix-loop-helix transcription factorsPlant Cell1630333044PubMedCrossRefGoogle Scholar
  24. Koornneef, M., Rolff, E., Spruit, C.J.P. 1980Genetic control of light-inhibited hypocotyl elongation in Arabidopsis thaliana (L.) HeynhZ. Pflanzenphysiol. Bd.100147160Google Scholar
  25. Lin, C. 2002Blue light receptors and signal transductionPlant Cell14S207S225PubMedGoogle Scholar
  26. Lin, C., Yang, H., Guo, H., Mockler, T., Chen, J., Cashmore, A.R. 1998Enhancement of blue-light sensitivity of Arabidopsis seedlings by a blue light receptor cryptochrome 2Proc. Natl. Acad. Sci. USA9526862690PubMedCrossRefGoogle Scholar
  27. Liu, Y.G., Mitsukawa, N., Oosumi, T., Whittier, R.F. 1995Efficient isolation and mapping of Arabidopsis thaliana T-DNA insert junctions by thermal asymmetric interlaced PCRPlant J.8457463PubMedCrossRefGoogle Scholar
  28. Más, P., Alabadí, D., Yanovsky, M.J., Oyama, T., Kay, S.A. 2003Dual role of TOC1 in the control of circadian and photomorphogenic responses in arabidopsisPlant Cell15223236PubMedCrossRefGoogle Scholar
  29. Más, P., Devlin, P.F., Panda, S., Kay, S.A. 2000Functional interaction of phytochrome B and cryptochrome 2Nature408207211PubMedCrossRefGoogle Scholar
  30. Mazzella, M.A., Casal, J.J. 2001Interactive signaling by phytochromes and cryptochromes generates de-etiolation homeostasis in ArabidopsisPlant Cell Environ.24155162Google Scholar
  31. Mockler, T.C., Guo, H., Yang, H., Duong, H., Lin, C. 1999Antagonistic actions of Arabidopsis cryptochromes and phytochrome B in the regulation of floral inductionDevelopment12620732082PubMedGoogle Scholar
  32. Oh, E., Kim, J., Park, E., Kim, J.I., Kang, C., Choi, G. 2004PIL5, a phytochrome-interacting basic helix-loop-helix protein, is a key negative regulator of seed germination in Arabidopsis thalianaPlant Cell1630453058PubMedCrossRefGoogle Scholar
  33. Ohtani, N., Zebedee, Z., Huot, T.J.G., Stinson, J.A., Sugimoto, M., Ohashi, Y., Sharrocks, A.D., Peters, G., Hara, E. 2001Opposing effects of Ets and Id proteins on p16INK4a expression during cellular senescenceNature40910671070PubMedCrossRefGoogle Scholar
  34. Salter, M.G., Franklin, K.A., Whitelam, G.C. 2003Gating of the rapid shade-avoidance response by the circadian clock in plantsNature426680683PubMedCrossRefGoogle Scholar
  35. Soh, M.S., Kim, Y.M., Han, S.J., Song, P.S. 2000REP1, a basic helix-loop-helix protein, is required for a branch pathway of phytochrome A signaling in ArabidopsisPlant Cell1220612074PubMedCrossRefGoogle Scholar
  36. Somers, D.E., Devlin, P.F., Kay, S.A. 1998Phytochromes and cryptochromes in the entrainment of the Arabidopsis circadian clockScience28214881490PubMedCrossRefGoogle Scholar
  37. Toledo-Ortiz, G., Huq, E., Quail, P.H. 2003The arabidopsis basic/helix-loop-helix transcription factor familyPlant Cell1517491770PubMedCrossRefGoogle Scholar
  38. Weigel, D., Ahn, J.H., Blázquez, M.A., Borevitz, J., Christensen, S.K., Fankhauser, C., Ferrándiz, C., Kardailsky, I., Malancharuvil, E.J., Neff, M.M., Nguyen, J.T., Sato, S., Wang, Z.Y., Xia, Y., Dixon, R.A., Harrison, M.J., Lamb, C.J., Yanofsky, M.F., Chory, J. 2000Activation tagging in ArabidopsisPlant Physiol.12210031013PubMedCrossRefGoogle Scholar
  39. Yamashino, T., Matsushika, A., Fujimori, T., Sato, S., Kato, T., Tabata, S., Mizuno, T. 2003A link between circadian-controlled bHLH factors and the APRR1/TOC1 quintet in Arabidopsis thalianaPlant Cell Physiol.44619629PubMedCrossRefGoogle Scholar
  40. Yanovsky, M.J., Kay, S.A. 2002Molecular basis of seasonal time measurement in ArabidopsisNature419308312PubMedCrossRefGoogle Scholar

Copyright information

© Springer 2006

Authors and Affiliations

  1. 1.Laboratory of Plant Developmental Genetics, Department of Biological SciencesSeoul National UniversitySeoulKorea
  2. 2.Plant Metabolism Research CenterKyung Hee UniversitySuwonKorea

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