COP1

Summary

Gene Symbol: COP1
Description: Transducin/WD40 repeat-like superfamily protein
Alias: ARABIDOPSIS THALIANA CONSTITUTIVE PHOTOMORPHOGENIC 1, ATCOP1, CONSTITUTIVE PHOTOMORPHOGENIC 1, DEETIOLATED MUTANT 340, DET340, EMB168, EMBRYO DEFECTIVE 168, FUS1, FUSCA 1, T21L14.11, T21L14_11, Transducin/WD40 repeat-like superfamily protein
Species: thale cress
Products:     COP1

Top Publications

  1. Saijo Y, Zhu D, Li J, Rubio V, Zhou Z, Shen Y, et al. Arabidopsis COP1/SPA1 complex and FHY1/FHY3 associate with distinct phosphorylated forms of phytochrome A in balancing light signaling. Mol Cell. 2008;31:607-13 pubmed publisher
    ..continuous far-red light and is rapidly destabilized upon red light irradiation by E3 ubiquitin ligases, including COP1. Here we provide evidence that the light signaling repressors SPA proteins contribute to COP1-mediated phyA ..
  2. Favory J, Stec A, Gruber H, Rizzini L, Oravecz A, Funk M, et al. Interaction of COP1 and UVR8 regulates UV-B-induced photomorphogenesis and stress acclimation in Arabidopsis. EMBO J. 2009;28:591-601 pubmed publisher
    ..UV RESPONSE LOCUS 8 (UVR8) and the multifunctional E3 ubiquitin ligase CONSTITUTIVELY PHOTOMORPHOGENIC 1 (COP1) are key regulators of the UV-B response...
  3. Bauer D, Viczian A, Kircher S, Nobis T, Nitschke R, Kunkel T, et al. Constitutive photomorphogenesis 1 and multiple photoreceptors control degradation of phytochrome interacting factor 3, a transcription factor required for light signaling in Arabidopsis. Plant Cell. 2004;16:1433-45 pubmed
    ..We demonstrate that accumulation of PIF3 in the nucleus in dark requires constitutive photomorphogenesis 1 (COP1), a negative regulator of photomorphogenesis, and show that red (R) and far-red light (FR) induce rapid degradation ..
  4. Ang L, Chattopadhyay S, Wei N, Oyama T, Okada K, Batschauer A, et al. Molecular interaction between COP1 and HY5 defines a regulatory switch for light control of Arabidopsis development. Mol Cell. 1998;1:213-22 pubmed
    Arabidopsis COP1 acts as a light-inactivable repressor of photomorphogenic development, but its molecular mode of action remains unclear...
  5. Liang X, Wang H, Mao L, Hu Y, Dong T, Zhang Y, et al. Involvement of COP1 in ethylene- and light-regulated hypocotyl elongation. Planta. 2012;236:1791-802 pubmed publisher
    ..CONSTITUTIVELY PHOTOMORPHOGENIC 1 (COP1) is an important downstream component of light signaling...
  6. Holm M, Ma L, Qu L, Deng X. Two interacting bZIP proteins are direct targets of COP1-mediated control of light-dependent gene expression in Arabidopsis. Genes Dev. 2002;16:1247-59 pubmed
    Arabidopsis COP1 acts to repress photomorphogenesis in the absence of light...
  7. Datta S, Hettiarachchi G, Deng X, Holm M. Arabidopsis CONSTANS-LIKE3 is a positive regulator of red light signaling and root growth. Plant Cell. 2006;18:70-84 pubmed
    CONSTITUTIVE PHOTOMORPHOGENIC1 (COP1) is an E3 ubiquitin ligase that represses photomorphogenesis in the dark. Therefore, proteins interacting with COP1 could be important regulators of light-dependent development...
  8. McNellis T, von Arnim A, Araki T, Komeda Y, Misera S, Deng X. Genetic and molecular analysis of an allelic series of cop1 mutants suggests functional roles for the multiple protein domains. Plant Cell. 1994;6:487-500 pubmed
    The Arabidopsis protein COP1, encoded by the constitutive photomorphogenic locus 1, is an essential regulatory molecule that plays a role in the repression of photomorphogenic development in darkness and in the ability of light-grown ..
  9. Liu B, Zuo Z, Liu H, Liu X, Lin C. Arabidopsis cryptochrome 1 interacts with SPA1 to suppress COP1 activity in response to blue light. Genes Dev. 2011;25:1029-34 pubmed publisher
    Plant photoreceptors mediate light suppression of the E3 ubiquitin ligase COP1 (CONSTITUTIVE PHOTOMORPHOGENIC 1) to affect gene expression and photomorphogenesis...

More Information

Publications73

  1. Osterlund M, Ang L, Deng X. The role of COP1 in repression of Arabidopsis photomorphogenic development. Trends Cell Biol. 1999;9:113-8 pubmed
    Photomorphogenic development in Arabidopsis is regulated by the key repressor COP1, which interacts with specific transcription factors in the nucleus to modulate their activities...
  2. Pacín M, Legris M, Casal J. COP1 re-accumulates in the nucleus under shade. Plant J. 2013;75:631-41 pubmed publisher
    ..CONSTITTUTIVE PHOTOMORPHOGENESIS 1 (COP1) is an E3 ligase involved in the ubiquitin labelling of proteins targeted for degradation...
  3. Osterlund M, Hardtke C, Wei N, Deng X. Targeted destabilization of HY5 during light-regulated development of Arabidopsis. Nature. 2000;405:462-6 pubmed
    ..Two key downstream components, COP1 and HY5, act antagonistically in regulating seedling development...
  4. Crefcoeur R, Yin R, Ulm R, Halazonetis T. Ultraviolet-B-mediated induction of protein-protein interactions in mammalian cells. Nat Commun. 2013;4:1779 pubmed publisher
    ..system based on the ultraviolet-B-dependent interaction of the Arabidopsis ultraviolet-B photoreceptor UVR8 with COP1 that can be performed in visible light background...
  5. Laubinger S, Hoecker U. The SPA1-like proteins SPA3 and SPA4 repress photomorphogenesis in the light. Plant J. 2003;35:373-85 pubmed
    ..further show that SPA3 as well as SPA4 can physically interact with the constitutive repressor of light signaling COP1. Deletion analyses suggest that SPA3 and SPA4, like SPA1, bind to the coiled-coil domain of COP1...
  6. Liu L, Zhang Y, Li Q, Sang Y, Mao J, Lian H, et al. COP1-mediated ubiquitination of CONSTANS is implicated in cryptochrome regulation of flowering in Arabidopsis. Plant Cell. 2008;20:292-306 pubmed publisher
    ..proposed that one of the mechanisms by which CRY regulates light responses is via its physical interaction with COP1, a RING motif-containing E3 ligase...
  7. Duek P, Elmer M, van Oosten V, Fankhauser C. The degradation of HFR1, a putative bHLH class transcription factor involved in light signaling, is regulated by phosphorylation and requires COP1. Curr Biol. 2004;14:2296-301 pubmed
    ..Light-regulated protein stability is a major control point of photomorphogenesis. The ubiquitin E3 ligase COP1 (constitutively photomorphogenic 1) regulates the stability of several light-signaling components...
  8. Wang X, Li W, Piqueras R, Cao K, Deng X, Wei N. Regulation of COP1 nuclear localization by the COP9 signalosome via direct interaction with CSN1. Plant J. 2009;58:655-67 pubmed publisher
    b>COP1 and COP9 signalosome (CSN) are key regulators of plant light responses and development. Deficiency in either COP1 or CSN causes a constitutive photomorphogenic phenotype...
  9. Zuo Z, Liu H, Liu B, Liu X, Lin C. Blue light-dependent interaction of CRY2 with SPA1 regulates COP1 activity and floral initiation in Arabidopsis. Curr Biol. 2011;21:841-7 pubmed publisher
    ..It has been reported that cryptochromes suppress activity of the multifunctional E3 ubiquitin ligase CONSTITUTIVE PHOTOMORPHOGENIC 1 (COP1) to regulate gene expression in response to blue light...
  10. Jang S, Marchal V, Panigrahi K, Wenkel S, Soppe W, Deng X, et al. Arabidopsis COP1 shapes the temporal pattern of CO accumulation conferring a photoperiodic flowering response. EMBO J. 2008;27:1277-88 pubmed publisher
    ..We show that mutations in CONSTITUTIVE PHOTOMORPHOGENIC 1 (COP1), a component of a ubiquitin ligase, cause extreme early flowering under SDs, and that this is ..
  11. Yanagawa Y, Sullivan J, Komatsu S, Gusmaroli G, Suzuki G, Yin J, et al. Arabidopsis COP10 forms a complex with DDB1 and DET1 in vivo and enhances the activity of ubiquitin conjugating enzymes. Genes Dev. 2004;18:2172-81 pubmed
    COP10 is a ubiquitin-conjugating enzyme variant (UEV), which is thought to act together with COP1, DET1, and the COP9 signalosome (CSN) in Arabidopsis to repress photomorphogenesis...
  12. Jang I, Yang J, Seo H, Chua N. HFR1 is targeted by COP1 E3 ligase for post-translational proteolysis during phytochrome A signaling. Genes Dev. 2005;19:593-602 pubmed
    ..The COP1 E3 ligase represses photomorphogenesis in part by targeting transcription activators such as LAF1 and HY5 for ..
  13. Stacey M, Kopp O, Kim T, von Arnim A. Modular domain structure of Arabidopsis COP1. Reconstitution of activity by fragment complementation and mutational analysis of a nuclear localization signal in planta. Plant Physiol. 2000;124:979-90 pubmed
    The Arabidopsis COP1 protein functions as a developmental regulator, in part by repressing photomorphogenesis in darkness...
  14. Datta S, Johansson H, Hettiarachchi C, Irigoyen M, Desai M, Rubio V, et al. LZF1/SALT TOLERANCE HOMOLOG3, an Arabidopsis B-box protein involved in light-dependent development and gene expression, undergoes COP1-mediated ubiquitination. Plant Cell. 2008;20:2324-38 pubmed publisher
    ..with two key regulators of light signaling, ELONGATED HYPOCOTYL5 (HY5) and CONSTITUTIVE PHOTOMORPHOGENIC1 (COP1)...
  15. Oravecz A, Baumann A, Mate Z, Brzezinska A, Molinier J, Oakeley E, et al. CONSTITUTIVELY PHOTOMORPHOGENIC1 is required for the UV-B response in Arabidopsis. Plant Cell. 2006;18:1975-90 pubmed
    CONSTITUTIVELY PHOTOMORPHOGENIC1 (COP1) is a negative regulator of photomorphogenesis in Arabidopsis thaliana. COP1 functions as an E3 ubiquitin ligase, targeting select proteins for proteasomal degradation in plants as well as in mammals...
  16. O Hara A, Jenkins G. In vivo function of tryptophans in the Arabidopsis UV-B photoreceptor UVR8. Plant Cell. 2012;24:3755-66 pubmed publisher
    ..of UVR8 from dimer to monomer, accumulation in the nucleus, and interaction with CONSTITUTIVELY PHOTOMORPHOGENIC1 (COP1), which functions with UVR8 in UV-B responses...
  17. Chen H, Huang X, Gusmaroli G, Terzaghi W, Lau O, Yanagawa Y, et al. Arabidopsis CULLIN4-damaged DNA binding protein 1 interacts with CONSTITUTIVELY PHOTOMORPHOGENIC1-SUPPRESSOR OF PHYA complexes to regulate photomorphogenesis and flowering time. Plant Cell. 2010;22:108-23 pubmed publisher
    CONSTITUTIVELY PHOTOMORPHOGENIC1 (COP1) possesses E3 ligase activity and promotes degradation of key factors involved in the light regulation of plant development...
  18. Heijde M, Ulm R. Reversion of the Arabidopsis UV-B photoreceptor UVR8 to the homodimeric ground state. Proc Natl Acad Sci U S A. 2013;110:1113-8 pubmed publisher
    ..configuration, which leads to interaction with the key signaling protein constitutively photomorphogenic 1 (COP1) and induction of UV-B-protective responses...
  19. Vandenbussche F, Habricot Y, Condiff A, Maldiney R, Van Der Straeten D, Ahmad M. HY5 is a point of convergence between cryptochrome and cytokinin signalling pathways in Arabidopsis thaliana. Plant J. 2007;49:428-41 pubmed
    ..increase levels of HY5 protein accumulation, suggesting that cytokinins may function by reducing HY5 degradation by COP1 (constitutively photomorphogenic 1)...
  20. Seo H, Yang J, Ishikawa M, Bolle C, Ballesteros M, Chua N. LAF1 ubiquitination by COP1 controls photomorphogenesis and is stimulated by SPA1. Nature. 2003;423:995-9 pubmed
    ..The RING motif protein COP1 is also important because cop1 mutants exhibit constitutive photomorphogenesis in darkness...
  21. Torii K, McNellis T, Deng X. Functional dissection of Arabidopsis COP1 reveals specific roles of its three structural modules in light control of seedling development. EMBO J. 1998;17:5577-87 pubmed
    Arabidopsis COP1 acts as a repressor of photomorphogenesis in darkness, and light stimuli abrogate the repressive ability and nuclear abundance of COP1...
  22. Huang X, Ouyang X, Yang P, Lau O, Li G, Li J, et al. Arabidopsis FHY3 and HY5 positively mediate induction of COP1 transcription in response to photomorphogenic UV-B light. Plant Cell. 2012;24:4590-606 pubmed publisher
    ..Here, we report that the multifunctional E3 ubiquitin ligase, CONSTITUTIVE PHOTOMORPHOGENESIS1 (COP1), a known key player in UV-B photomorphogenic responses, is also a UV-B-inducible gene...
  23. Nakagawa M, Komeda Y. Flowering of Arabidopsis cop1 mutants in darkness. Plant Cell Physiol. 2004;45:398-406 pubmed
    To elucidate the role of the COP1 gene in flowering, we analyzed flowering of cop1 mutant lines in darkness. When grown in the presence of 1% (w/v) sucrose, the cop1-6 mutant flowered in darkness, but cop1-1 and cop1-4 did not...
  24. Yang J, Lin R, Sullivan J, Hoecker U, Liu B, Xu L, et al. Light regulates COP1-mediated degradation of HFR1, a transcription factor essential for light signaling in Arabidopsis. Plant Cell. 2005;17:804-21 pubmed
    ..We demonstrate that HFR1 physically interacts with Constitutive Photomorphogenesis 1 (COP1) and that COP1 exhibits ubiquitin ligase activity toward HFR1 in vitro...
  25. Saijo Y, Sullivan J, Wang H, Yang J, Shen Y, Rubio V, et al. The COP1-SPA1 interaction defines a critical step in phytochrome A-mediated regulation of HY5 activity. Genes Dev. 2003;17:2642-7 pubmed
    Arabidopsis COP1 is a constitutive repressor of photomorphogenesis that interacts with photomorphogenesis-promoting factors such as HY5 to promote their proteasome-mediated degradation...
  26. Jang I, Henriques R, Seo H, Nagatani A, Chua N. Arabidopsis PHYTOCHROME INTERACTING FACTOR proteins promote phytochrome B polyubiquitination by COP1 E3 ligase in the nucleus. Plant Cell. 2010;22:2370-83 pubmed publisher
    ..Nuclear phyB degradation is mediated by COP1 E3 ligase, which preferentially interacts with the PhyB N-terminal region (PhyB-N)...
  27. Hoecker U, Quail P. The phytochrome A-specific signaling intermediate SPA1 interacts directly with COP1, a constitutive repressor of light signaling in Arabidopsis. J Biol Chem. 2001;276:38173-8 pubmed
    ..that shows high sequence similarity to the WD-repeat region of the constitutive repressor of light signaling, COP1. Here, using yeast two-hybrid and in vitro interaction assays, we show that SPA1 strongly and selectively binds to ..
  28. Cloix C, Kaiserli E, Heilmann M, Baxter K, Brown B, O Hara A, et al. C-terminal region of the UV-B photoreceptor UVR8 initiates signaling through interaction with the COP1 protein. Proc Natl Acad Sci U S A. 2012;109:16366-70 pubmed publisher
    ..in the nucleus, where it binds to chromatin, and induces interaction of UVR8 with CONSTITUTIVELY PHOTOMORPHOGENIC1 (COP1), which functions with UVR8 to control photomorphogenic UV-B responses...
  29. Hong S, Kim H, Ryu J, Choi H, Jeong S, Shin J, et al. CRY1 inhibits COP1-mediated degradation of BIT1, a MYB transcription factor, to activate blue light-dependent gene expression in Arabidopsis. Plant J. 2008;55:361-71 pubmed publisher
    ..In contrast, COP1 binds to BIT1 and mediates its degradation...
  30. Wang H, Ma L, Li J, Zhao H, Deng X. Direct interaction of Arabidopsis cryptochromes with COP1 in light control development. Science. 2001;294:154-8 pubmed
    Arabidopsis seedling photomorphogenesis involves two antagonistically acting components, COP1 and HY5. COP1 specifically targets HY5 for degradation via the 26S proteasome in the dark through their direct physical interaction...
  31. Gruber H, Heijde M, Heller W, Albert A, Seidlitz H, Ulm R. Negative feedback regulation of UV-B-induced photomorphogenesis and stress acclimation in Arabidopsis. Proc Natl Acad Sci U S A. 2010;107:20132-7 pubmed publisher
    ..The key players in this UV-B response are COP1 (an E3 ubiquitin ligase), UVR8 (a ?-propeller protein), and HY5 (a bZIP transcription factor)...
  32. Subramanian C, Kim B, Lyssenko N, Xu X, Johnson C, von Arnim A. The Arabidopsis repressor of light signaling, COP1, is regulated by nuclear exclusion: mutational analysis by bioluminescence resonance energy transfer. Proc Natl Acad Sci U S A. 2004;101:6798-802 pubmed
    ..on protein-protein interactions in live plant cells by using the Arabidopsis Constitutive photomorphogenesis 1 (COP1) protein as a model system...
  33. Yang H, Tang R, Cashmore A. The signaling mechanism of Arabidopsis CRY1 involves direct interaction with COP1. Plant Cell. 2001;13:2573-87 pubmed
    ..The phenotypic properties mediated by CCT are remarkably similar to those of the constitutive photomorphogenic1 (cop1) mutants...
  34. Holm M, Hardtke C, Gaudet R, Deng X. Identification of a structural motif that confers specific interaction with the WD40 repeat domain of Arabidopsis COP1. EMBO J. 2001;20:118-27 pubmed
    Arabidopsis COP1 is a photomorphogenesis repressor capable of directly interacting with the photomorphogenesis-promoting factor HY5. This interaction between HY5 and COP1 results in targeted deg radation of HY5 by the 26S proteasome...
  35. Feher B, Kozma Bognar L, Kevei E, Hajdu A, Binkert M, Davis S, et al. Functional interaction of the circadian clock and UV RESISTANCE LOCUS?8-controlled UV-B signaling pathways in Arabidopsis thaliana. Plant J. 2011;67:37-48 pubmed publisher
    ..UV RESISTANCE LOCUS?8 (UVR8) and CONSTITUTIVELY PHOTOMORPHOGENIC?1 (COP1) are required, but ELONGATED HYPOCOTYL?5 (HY5) and HY5 HOMOLOG (HYH) are dispensable for this process...
  36. Seo H, Watanabe E, Tokutomi S, Nagatani A, Chua N. Photoreceptor ubiquitination by COP1 E3 ligase desensitizes phytochrome A signaling. Genes Dev. 2004;18:617-22 pubmed
    ..The phyA PAS domain interacts with the COP1 WD40 domain...
  37. Yu J, Rubio V, Lee N, Bai S, Lee S, Kim S, et al. COP1 and ELF3 control circadian function and photoperiodic flowering by regulating GI stability. Mol Cell. 2008;32:617-30 pubmed publisher
    ..Blue-light-sensing cryptochromes, the E3 ubiquitin-ligase COP1, and clock-associated proteins ELF3 and GI regulate this process, although the regulatory link between them is ..
  38. Mao J, Zhang Y, Sang Y, Li Q, Yang H. From The Cover: A role for Arabidopsis cryptochromes and COP1 in the regulation of stomatal opening. Proc Natl Acad Sci U S A. 2005;102:12270-5 pubmed
    ..Here, we report a previously uncharacterized role for Arabidopsis CRY and COP1 in the regulation of stomatal opening...
  39. Huang X, Ouyang X, Yang P, Lau O, Chen L, Wei N, et al. Conversion from CUL4-based COP1-SPA E3 apparatus to UVR8-COP1-SPA complexes underlies a distinct biochemical function of COP1 under UV-B. Proc Natl Acad Sci U S A. 2013;110:16669-74 pubmed publisher
    The evolutionarily conserved constitutive photomorphogenesis 1 (COP1) is a RING and WD40 protein that functions as a substrate receptor of CULLIN4-damaged DNA binding protein 1 (CUL4-DDB1)-based E3 ubiquitin ligases in both plants and ..
  40. Heijde M, Binkert M, Yin R, Ares Orpel F, Rizzini L, Van De Slijke E, et al. Constitutively active UVR8 photoreceptor variant in Arabidopsis. Proc Natl Acad Sci U S A. 2013;110:20326-31 pubmed publisher
    ..results in its instantaneous monomerization followed by interaction with CONSTITUTIVELY PHOTOMORPHOGENIC 1 (COP1), a major factor in UV-B signaling...
  41. Chen H, Shen Y, Tang X, Yu L, Wang J, Guo L, et al. Arabidopsis CULLIN4 Forms an E3 Ubiquitin Ligase with RBX1 and the CDD Complex in Mediating Light Control of Development. Plant Cell. 2006;18:1991-2004 pubmed
    Repression of photomorphogenesis in Arabidopsis thaliana requires activity of the COP9 signalosome (CSN), CDD, and COP1 complexes, but how these three complexes work in concert to accomplish this important developmental switch has ..
  42. Chen S, Lory N, Stauber J, Hoecker U. Photoreceptor Specificity in the Light-Induced and COP1-Mediated Rapid Degradation of the Repressor of Photomorphogenesis SPA2 in Arabidopsis. PLoS Genet. 2015;11:e1005516 pubmed publisher
    The Arabidopsis COP1/SPA E3 ubiquitin ligase is a key negative regulator that represses light signaling in darkness by targeting transcription factors involved in the light response for degradation...
  43. Yin R, Skvortsova M, Loubéry S, Ulm R. COP1 is required for UV-B-induced nuclear accumulation of the UVR8 photoreceptor. Proc Natl Acad Sci U S A. 2016;113:E4415-22 pubmed publisher
    ..Here, we show that CONSTITUTIVELY PHOTOMORPHOGENIC 1 (COP1) is required for UV-B-induced nuclear accumulation of UVR8, but bypassing the COP1 requirement for UVR8 nuclear ..
  44. Debrieux D, Trevisan M, Fankhauser C. Conditional involvement of constitutive photomorphogenic1 in the degradation of phytochrome A. Plant Physiol. 2013;161:2136-45 pubmed publisher
    ..Cullin1 and the ubiquitin E3 ligase constitutive photomorphogenic1 (COP1) have been implicated in this process...
  45. Schrader A, Welter B, Hulskamp M, Hoecker U, Uhrig J. MIDGET connects COP1-dependent development with endoreduplication in Arabidopsis thaliana. Plant J. 2013;75:67-79 pubmed publisher
    In Arabidopsis thaliana, loss of CONSTITUTIVE PHOTOMORPHOGENIC 1 (COP1) function leads to constitutive photomorphogenesis in the dark associated with inhibition of endoreduplication in the hypocotyl, and a post-germination growth arrest...
  46. Adams E, Diaz C, Hong J, Shin R. 14-3-3 proteins participate in light signaling through association with PHYTOCHROME INTERACTING FACTORs. Int J Mol Sci. 2014;15:22801-14 pubmed publisher
    ..kappa isoform (14-3-3κ) could bind to PHYTOCHROME INTERACTING FACTOR3 (PIF3) and CONSTITUTIVE PHOTOMORPHOGENIC1 (COP1). Further analysis by in vitro pull-down assay confirmed the interaction between 14-3-3κ and PIF3...
  47. Lin X, Niu D, Hu Z, Kim D, Jin Y, Cai B, et al. An Arabidopsis SUMO E3 Ligase, SIZ1, Negatively Regulates Photomorphogenesis by Promoting COP1 Activity. PLoS Genet. 2016;12:e1006016 pubmed publisher
    COP1 (CONSTITUTIVE PHOTOMORPHOGENIC 1), a ubiquitin E3 ligase, is a central negative regulator of photomorphogenesis. However, how COP1 activity is regulated by post-translational modifications remains largely unknown...
  48. Dohmann E, Levesque M, De Veylder L, Reichardt I, Jurgens G, Schmid M, et al. The Arabidopsis COP9 signalosome is essential for G2 phase progression and genomic stability. Development. 2008;135:2013-22 pubmed publisher
    ..is also apparent in mutants of the NEDD8 conjugation pathway and in mutants of the E3 ligase subunits CULLIN4, COP1 and DET1, which share phenotypes with csn mutants...
  49. Yamamoto Y, Deng X, Matsui M. Cip4, a new COP1 target, is a nucleus-localized positive regulator of Arabidopsis photomorphogenesis. Plant Cell. 2001;13:399-411 pubmed
    Arabidopsis COP1 acts within the nucleus to repress photomorphogenesis, and its nuclear abundance is negatively regulated by light. Here, we report the identification of a COP1-interactive partner, CIP4...
  50. Mallappa C, Singh A, Ram H, Chattopadhyay S. GBF1, a transcription factor of blue light signaling in Arabidopsis, is degraded in the dark by a proteasome-mediated pathway independent of COP1 and SPA1. J Biol Chem. 2008;283:35772-82 pubmed publisher
    ..the genetic and molecular interrelation of GBF1 with two well characterized negative regulators of light signaling, COP1 and SPA1, in photomorphogenic growth and light-regulated gene expression...
  51. Crocco C, Holm M, Yanovsky M, Botto J. AtBBX21 and COP1 genetically interact in the regulation of shade avoidance. Plant J. 2010;64:551-62 pubmed publisher
    ..Mutations in the photomorphogenic repressor COP1 suppress the SAS, but how COP1 modulates these responses is uncertain...
  52. Jiang L, Wang Y, Li Q, Björn L, He J, Li S. Arabidopsis STO/BBX24 negatively regulates UV-B signaling by interacting with COP1 and repressing HY5 transcriptional activity. Cell Res. 2012;22:1046-57 pubmed publisher
    ..and several key players in this response have been identified, which include UVR8 (a UV-B-specific photoreceptor), COP1 (a WD40-repeat-containing RING finger protein), HY5 (a basic zipper transcription factor), and RUP1/2 (two UVR8-..
  53. Chen X, Lin W, Wang Y, Luan S, Xue H. An inositol polyphosphate 5-phosphatase functions in PHOTOTROPIN1 signaling in Arabidopis by altering cytosolic Ca2+. Plant Cell. 2008;20:353-66 pubmed publisher
  54. Wang J, Chen C, Chien C, Hsieh H. FAR-RED INSENSITIVE219 modulates CONSTITUTIVE PHOTOMORPHOGENIC1 activity via physical interaction to regulate hypocotyl elongation in Arabidopsis. Plant Physiol. 2011;156:631-46 pubmed publisher
    ..Previous genetic studies revealed that FIN219 acts as an extragenic suppressor of CONSTITUTIVE PHOTOMORPHOGENIC1 (COP1). However, the molecular mechanism underlying the suppression of COP1 remains unknown...
  55. Hardtke C, Okamoto H, Stoop Myer C, Deng X. Biochemical evidence for ubiquitin ligase activity of the Arabidopsis COP1 interacting protein 8 (CIP8). Plant J. 2002;30:385-94 pubmed
    Arabidopsis COP1 is a negative regulator of photomorphogenesis, which targets HY5, a positive regulator of photomorphogenesis, for degradation via the proteasome pathway in the absence of light...
  56. Xu X, Paik I, Zhu L, Bu Q, Huang X, Deng X, et al. PHYTOCHROME INTERACTING FACTOR1 Enhances the E3 Ligase Activity of CONSTITUTIVE PHOTOMORPHOGENIC1 to Synergistically Repress Photomorphogenesis in Arabidopsis. Plant Cell. 2014;26:1992-2006 pubmed
    CONSTITUTIVE PHOTOMORPHOGENIC1 (COP1) is a RING/WD40 repeat-containing ubiquitin E3 ligase that is conserved from plants to humans...
  57. Viczian A, Adam E, Wolf I, Bindics J, Kircher S, Heijde M, et al. A short amino-terminal part of Arabidopsis phytochrome A induces constitutive photomorphogenic response. Mol Plant. 2012;5:629-41 pubmed publisher
    ..We demonstrate that in vitro and in vivo PHYA406 Pfr and Pr bind COP1, a general repressor of photomorphogenesis, and co-localize with it in nuclear bodies...
  58. Klose C, Buche C, Fernández A, Schafer E, Zwick E, Kretsch T. The mediator complex subunit PFT1 interferes with COP1 and HY5 in the regulation of Arabidopsis light signaling. Plant Physiol. 2012;160:289-307 pubmed publisher
    ..Our data further indicate that PFT1 regulates the floral transition downstream of phyA. The PFT1 missense mutation seems to create a constitutively active transcription factor by mimicking an early step in light signaling. ..
  59. Srivastava A, Senapati D, Srivastava A, Chakraborty M, Gangappa S, Chattopadhyay S. Short Hypocotyl in White Light1 Interacts with Elongated Hypocotyl5 (HY5) and Constitutive Photomorphogenic1 (COP1) and Promotes COP1-Mediated Degradation of HY5 during Arabidopsis Seedling Development. Plant Physiol. 2015;169:2922-34 pubmed publisher
    ..SHW1 and Constitutive Photomorphogenic1 (COP1) genetically interact in an additive manner to suppress photomorphogenesis...
  60. Yan H, Marquardt K, Indorf M, Jutt D, Kircher S, Neuhaus G, et al. Nuclear localization and interaction with COP1 are required for STO/BBX24 function during photomorphogenesis. Plant Physiol. 2011;156:1772-82 pubmed publisher
    ..signal transduction that localizes to the nucleus of plant cells and interacts with CONSTITUTIVE PHOTOMORPHOGENIC1 (COP1) in the yeast (Saccharomyces cerevisiae) two-hybrid system...
  61. Yang J, Lin R, Hoecker U, Liu B, Xu L, Wang H. Repression of light signaling by Arabidopsis SPA1 involves post-translational regulation of HFR1 protein accumulation. Plant J. 2005;43:131-41 pubmed
    ..Arabidopsis COP1 represses light signaling by acting as an E3 ubiquitin ligase in the nucleus, and is responsible for targeted ..
  62. Zhu D, Maier A, Lee J, Laubinger S, Saijo Y, Wang H, et al. Biochemical characterization of Arabidopsis complexes containing CONSTITUTIVELY PHOTOMORPHOGENIC1 and SUPPRESSOR OF PHYA proteins in light control of plant development. Plant Cell. 2008;20:2307-23 pubmed publisher
    b>COP1 (for CONSTITUTIVELY PHOTOMORPHOGENIC1) and the four partially redundant SPA (for SUPPRESSOR OF PHYA) proteins work in concert to repress photomorphogenesis in Arabidopsis thaliana by targeting key transcription factors and ..
  63. Sheerin D, Menon C, Zur Oven Krockhaus S, Enderle B, Zhu L, Johnen P, et al. Light-activated phytochrome A and B interact with members of the SPA family to promote photomorphogenesis in Arabidopsis by reorganizing the COP1/SPA complex. Plant Cell. 2015;27:189-201 pubmed publisher
    ..dark-grown seedlings, photomorphogenic growth is suppressed by the action of the CONSTITUTIVELY PHOTOMORPHOGENIC1 (COP1)/SUPPRESSOR OF phyA-105 (SPA) complex, which targets positive regulators of photomorphogenic growth for degradation ..
  64. Jang I, Yang S, Yang J, Chua N. Independent and interdependent functions of LAF1 and HFR1 in phytochrome A signaling. Genes Dev. 2007;21:2100-11 pubmed
    ..Polyubiquitinations of LAF1 and HFR1 by the COP1 E3 ligase in vitro are inhibited by LAF1/HFR1 association...