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Busch A, Gerbracht JV, Davies K, Hoecker U, Hess S (2024). Comparative transcriptomics illuminates the cellular responses of an aeroterrestrial zygnematophyte to UV radiation. J Exp Bot. Mar 23:erae131. doi:10.1093/jxb/erae131. Online ahead of print.

Liu W, Giuriani G, Havlikova A, Li D, Lamont DJ, Neugart S, Velanis CN, Petersen J, Hoecker U, Christie JM, Jenkins GI (2024). Phosphorylation of Arabidopsis UVR8 photoreceptor modulates protein interactions and responses to UV-B radiation. Nat Commun.15: 1221. doi:10.1038/s41467-024-45575-7.

Dadras A, Fürst-Jansen JMR, Darienko T, Krone D, Scholz P, Sun S, Herrfurth C, Reiseberg TP, Irisarri I, Steinkamp R, Hansen M, Buschmann H, Valerius O, Braus GH, Hoecker U, Feussner I, Mutwil M, Ischebeck T, de Vries S, Lorenz M, de Vries J (2023). Environmental gradients reveal stress hubs pre-dating plant terrestrialization. Nat Plants ):1419-1438.doi:10.1038/s41477-023-01491-0.

Kreiss M, Haas FB, Hansen M, Rensing SA, Hoecker U (2023). Co-action of COP1, SPA and cryptochrome in light signal transduction and photomorphogenesis of the moss Physcomitrium patens. Plant J. 14:159-175. doi:10.1111/tpj.16128

Hwang Y, Han S, Yoo CY, Hong L, You C, Le BH, Shi H, Zhong S, Hoecker U, Chen X, Chen M. (2022).  Anterograde signaling controls plastid transcription via sigma factors separately from nuclear photosynthesis genes.  Nat Commun. 13: 7440. DOI: 10.1038/s41467-022-35080-0

Trimborn L, Hoecker U, Ponnu J (2022). A simple quantitative assay for measuring β-galactosidase activity using X-gal in yeast-based interaction analyses. Curr. Protoc. 2(5):e421. doi: 10.1002/cpz1.421.

Ponnu J, Hoecker U (2022). Signaling mechanisms by Arabidopsis cryptochromes. Front Plant Sci. 13: 844714.

Kerner K, Nagano S, Lübbe A, Hoecker U (2021).  Functional comparison of the WD-repeat domains of SPA1 and COP1 in suppression of photomorphogenesis. Plant Cell Environ. 44: 3273-3282

Frerigmann H, Hoecker U, Gigolashvili T. (2021). New insights on the regulation of glucosinolate biosynthesis via COP1 and DELLA proteins in Arabidopsis thaliana. Front Plant Sci. 12: 680255

Schenk T, Trimborn L, Chen S, Schenkel C, Hoecker U (2021). Light-induced degradation of SPA2 via its N-terminal kinase domain is required for photomorphogenesis. Plant Physiol. 187: 276-288. 

Ponnu J, Hoecker U. (2021).  Illuminating the COP1/SPA ubiquitin ligase: Fresh insights into its structure and functions during plant photomorphogenesis. Front Plant Sci. 2021 Mar 24;12:662793. doi: 10.3389/fpls.2021.662793. eCollection 2021.

Schwenk P, Sheerin DJ, Ponnu J, Staudt AM, Lesch KL, Lichtenberg E, Medzihradszky KF, Hoecker U, Klement E, Viczián A, Hiltbrunner A. (2021). Uncovering a novel function of the CCR4-NOT complex in phytochrome A-mediated light signalling in plants. Elife 10: e63697. 

Kahle N, Sheerin DJ, Fischbach P, Koch LA, Schwenk P, Lambert D, Rodriguez R, Kerner K, Hoecker U, Zurbriggen MD, Hiltbrunner A. (2020). COLD REGULATED 27 and 28 are targets of CONSTITUTIVELY PHOTOMORPHOGENIC 1 and negatively affect phytochrome B signalling. Plant J. 104: 1038-1053.

Pham VN, Paik I, Hoecker U, Huq E. (2020). Genomic evidence reveals SPA-regulated developmental and metabolic pathways in dark-grown Arabidopsis seedlings. Physiol Plant. 169: 380-396.

Ponnu J (2020). Molecular mechanisms suppressing COP1/SPA E3 ubiquitin ligase activity in blue light. Physiol Plant. 2020 169: 418-429.

Pham VN, Paik I, Hoecker U, Hug E (2020). Genomic evidence reveals SPA-regulated developmental and metabolic pathways in dark-grown Arabidopsis seedlings. Physiol. Plant. 169: 380-396.

Ponnu J, Riedel T, Penner E, Schrader A, Hoecker U (2019). Cryptochrome 2 competes with COP1 substrates to repress COP1 ubiquitin ligase activity during Arabidopsis photomorphogenesis. Proc Natl Acad Sci U S A 116: 27133-41.

Sharma A, Sharma B, Hayes S, Kerner K, Hoecker U, Jenkins GI, Franklin KA (2019). UVR8 disrupts stabilisation of PIF5 by COP1 to inhibit plant stem elongation in sunlight. Nat Commun.10(1):4417.

Artz O, Dickopf S, Ranjan A, Kreiss M, Abraham ET, Boll V, Rensing SA, Hoecker U. (2019). Characterization of spa mutants in the moss Physcomitrella provides evidence for functional divergence of SPA genes during the evolution of land plants. New Phytol. 224(4):1613-1626.

Bhatia, C., Pandey, A., Gaddam, S., Hoecker, U. and Trivedi, P. (2018). Low Temperature-Enhanced Flavonol Synthesis Requires Light-Associated Regulatory Components in Arabidopsis thaliana. Plant and Cell Physiology, 59(10), pp. 2099-2112.

Ordonez-Herrera, N., Trimborn, L., Menje, M., Henschel, M., Robers, L., Kaufholdt, D., Hansch, R., Adrian, J., Ponnu, J. and Hoecker, U. (2018). The Transcription Factor COL12 Is a Substrate of the COP1/SPA E3 Ligase and Regulates Flowering Time and Plant Architecture. Plant Physiology, 176(2), pp. 1327-1340.

Arthaut, L., Jourdan, N., Mteyrek, A., Procopio, M., El-Esawi, M., d'Harlingue, A., Bouchet, P., Witczak, J., Ritz, T., Klarsfeld, A., Birman, S., Usselman, R., Hoecker, U., Martino, C. and Ahmad, M. (2017). Blue-light induced accumulation of reactive oxygen species is a consequence of the Drosophila cryptochrome photocycle. Plos One, 12: e0171836.

Balcerowicz, M., Kerner, K., Schenkel, C. and Hoecker, U. (2017). SPA Proteins Affect the Subcellular Localization of COP1 in the COP1/SPA Ubiquitin Ligase Complex during Photomorphogenesis. Plant Physiology, 174(3), pp. 1314-1321.

Hoecker, U. (2017). The activities of the E3 ubiquitin ligase COP1/SPA, a key repressor in light signaling. Current Opinion in Plant Biology, 37, pp. 63-69.

Holtkotte, X., Ponnu, J., Ahmad, M. and Hoecker, U. (2017). The blue light-induced interaction of cryptochrome 1 with COP1 requires SPA proteins during Arabidopsis light signaling. Plos Genetics, 13(10): e1007044.

Chen, S., Wirthmueller, L., Stauber, J., Lory, N., Holtkotte, X., Leson, L., Schenkel, C., Ahmad, M. and Hoecker, U. (2016). The functional divergence between SPA1 and SPA2 in Arabidopsis photomorphogenesis maps primarily to the respective N-terminal kinase-like domain. BMC Plant Biology, 16

Holtkotte, X., Dieterle, S., Kokkelink, L., Artz, O., Leson, L., Fittinghoff, K., Hayama, R., Ahmad, M. and Hoecker, U. (2016). Mutations in the N-terminal kinase-like domain of the repressor of photomorphogenesis SPA1 severely impair SPA1 function but not light responsiveness in Arabidopsis. Plant Journal, 88(2), pp. 205-218.

Jaegle, B., Uroic, M., Holtkotte, X., Lucas, C., Termath, A., Schmalz, H., Bucher, M., Hoecker, U., Hulskamp, M. and Schrader, A. (2016). A fast and simple LC-MS-based characterization of the flavonoid biosynthesis pathway for few seed(ling)s. BMC Plant Biology, 16

Chen, S., Lory, N., Stauber, J. and Hoecker, U. (2015). Photoreceptor Specificity in the Light-Induced and COP1-Mediated Rapid Degradation of the Repressor of Photomorphogenesis SPA2 in Arabidopsis. Plos Genetics, 11(9)

Maier, A. and Hoecker, U. (2015). COP1/SPA ubiquitin ligase complexes repress anthocyanin accumulation under low light and high light conditions. Plant Signaling & Behavior, 10(1)

Ordonez-Herrera, N., Fackendahl, P., Yu, X., Schaefer, S., Koncz, C. and Hoecker, U. (2015). A cop1 spa Mutant Deficient in COP1 and SPA Proteins Reveals Partial Co-Action of COP1 and SPA during Arabidopsis Post-Embryonic Development and Photomorphogenesis. Molecular Plant, 8(3), pp. 479-481.

Zhu, L., Bu, Q., Xu, X., Paik, I., Huang, X., Hoecker, U., Deng, X. and Huq, E. (2015). CUL4 forms an E3 ligase with COP1 and SPA to promote light-induced degradation of PIF1. Nature Communications,6

Balcerowicz, M. and Hoecker, U. (2014). Auxin - a novel regulator of stomata differentiation. Trends in Plant Science, 19(12), pp. 747-749.

Balcerowicz, M., Ranjan, A., Rupprecht, L., Fiene, G. and Hoecker, U. (2014). Auxin represses stomatal development in dark-grown seedlings via Aux/IAA proteins. Development, 141(16), pp. 3165-3176.

Ranjan, A., Dickopf, S., Ullrich, K., Rensing, S. and Hoecker, U. (2014). Functional analysis of COP1 and SPA orthologs from Physcomitrella and rice during photomorphogenesis of transgenic Arabidopsis reveals distinct evolutionary conservation. BMC Plant Biology,14: 178 (1-15).

Maier, A., Schrader, A., Kokkelink, L., Falke, C., Welter, B., Iniesto, E., Rubio, V., Uhrig, J., Hulskamp, M. and Hoecker, U. (2013). Light and the E3 ubiquitin ligase COP1/SPA control the protein stability of the MYB transcription factors PAP1 and PAP2 involved in anthocyanin accumulation in Arabidopsis. Plant Journal, 74(4), pp. 638-651.

Schrader, A., Welter, B., Hulskamp, M., Hoecker, U. and Uhrig, J. (2013). MIDGET connects COP1-dependent development with endoreduplication in Arabidopsis thaliana. Plant Journal, 75(1), pp. 67-79.

Rangani, G., Khodakovskaya, M., Alimohammadi, M., Hoecker, U. and Srivastava, V. (2012). Site-specific methylation in gene coding region underlies transcriptional silencing of the Phytochrome A epiallele in Arabidopsis thaliana. Plant Molecular Biology, 79(1-2), pp. 191-202.

Rolauffs, S., Fackendahl, P., Sahm, J., Fiene, G. and Hoecker, U. (2012). Arabidopsis COP1 and SPA Genes Are Essential for Plant Elongation But Not for Acceleration of Flowering Time in Response to a Low Red Light to Far-Red Light Ratio. Plant Physiology, 160(4), pp. 2015-2027.

Weidler, G., zur Oven-Krockhaus, S., Heunemann, M., Orth, C., Schleifenbaum, F., Harter, K., Hoecker, U. and Batschauer, A. (2012). Degradation of Arabidopsis CRY2 Is Regulated by SPA Proteins and Phytochrome A. Plant Cell, 24(6), pp. 2610-2623.

Balcerowicz, M., Fittinghoff, K., Wirthmueller, L., Maier, A., Fackendahl, P., Fiene, G., Koncz, C. and Hoecker, U. (2011). Light exposure of Arabidopsis seedlings causes rapid de-stabilization as well as selective post-translational inactivation of the repressor of photomorphogenesis SPA2. Plant Journal, 65(5), pp. 712-723.

Nicholson, S., Hoecker, U. and Srivastava, V. (2011). A novel Phytochrome B allele in Arabidopsis thaliana exhibits partial mutant phenotype: a short deletion in N-terminal extension reduces Phytochrome B activity. Plant Growth Regulation, 65(1), pp. 207-212.

Ranjan, A., Fiene, G., Fackendahl, P. and Hoecker, U. (2011). The Arabidopsis repressor of light signaling SPA1 acts in the phloem to regulate seedling de-etiolation, leaf expansion and flowering time. Development, 138(9), pp. 1851-1862.

Nixdorf, M. and Hoecker, U. (2010). SPA1 and DET1 act together to control photomorphogenesis throughout plant development. Planta, 231(4), pp. 825-833.

Sellaro, R., Hoecker, U., Yanovsky, M., Chory, J. and Casal, J. (2009). Synergism of Red and Blue Light in the Control of Arabidopsis Gene Expression and Development. Current Biology, 19(14), pp. 1216-1220.

Saijo, Y., Zhu, D., Li, J., Rubio, V., Zhou, Z., Shen, Y., Hoecker, U., Wang, H. and Deng, X. (2008). Arabidopsis COP1/SPA1 complex and FHY1/FHY3 associate with distinct phosphorylated forms of phytochrome a in balancing light signaling. Molecular Cell, 31(4), pp. 607-613.

Zhu, D., Maier, A., Lee, J., Laubinger, S., Saijo, Y., Wang, H., Qu, L., Hoecker, U. and Deng, X. (2008). Biochemical Characterization of Arabidopsis Complexes Containing CONSTITUTIVELY PHOTOMORPHOGENIC1 and SUPPRESSOR OF PHYA Proteins in Light Control of Plant Development. Plant Cell, 20(9), pp. 2307-2323.

Berns, M., Matsubara, S., Wise, A., Gilmer, F., Schurr, U., Walter, A. and Hocker, U. (2007). Diel leaf growth pattern in cry1cry2 mutants of Arabidopsis thaliana under different light conditions. Comparative Biochemistry and Physiology a-Molecular & Integrative Physiology, 146(4), pp. S233-S233.

Hoecker, U. (2007). SPA proteins are key repressors in light signal transduction and photoperiodic flowering. Comparative Biochemistry and Physiology a-Molecular & Integrative Physiology, 146(4), pp. S228-S229.

Fittinghoff, K., Laubinger, S., Nixdorf, M., Fackendahl, P., Baumgardt, R., Batschauer, A. and Hoecker, U. (2006). Functional and expression analysis of Arabidopsis SPA genes during seedling photomorphogenesis and adult growth. Plant Journal, 47(4), pp. 577-590.

Laubinger, S., Marchal, V., Gentilhomme, J., Wenkel, S., Adrian, J., Jang, S., Kulajta, C., Braun, H., Coupland, G. and Hoecker, U. (2006). Arabidopsis SPA proteins regulate photoperiodic flowering and interact with the floral inducer CONSTANS to regulate its stability (vol 133, pg 3213, 2006). Development, 133(22), pp. 4608-4608.

Hoecker, U. (2005). Regulated proteolysis in light signaling. Current Opinion in Plant Biology, 8(5), pp. 469-476.

Yang, J., Lin, R., Hoecker, U., Liu, B., Xu, L. and Wang, H. (2005). Repression of light signaling by Arabidopsis SPA1 involves post-translational regulation of HFR1 protein accumulation. Plant Journal, 43(1), pp. 131-141.

Yang, J., Lin, R., James, S., Hoecker, U., Liu, B., Xu, L., Deng, X. and Wang, H. (2005). Light regulates COP1-mediated degradation of HFR1, a transcription factor essential for light signaling in arabidopsis. Plant Cell, 17(3), pp. 804-821.

Hoecker, U., Toledo-Ortiz, G., Bender, J. and Quail, P. (2004). The photomorphogenesis-related mutant red1 is defective in CYP83B1, a red light-induced gene encoding a cytochrome P450 required for normal auxin homeostasis. Planta, 219(2), pp. 195-200.

Laubinger, S., Fittinghoff, K. and Hoecker, U. (2004). The SPA quartet: A family of WD-repeat proteins with a central role in suppression of photomorphogenesis in arabidopsis. Plant Cell, 16(9), pp. 2293-2306.

Laubinger, S. and Hoecker, U. (2003). The SPA1-like proteins SPA3 and SPA4 repress photomorphogenesis in the light. Plant Journal, 35(3), pp. 373-385.

Saijo, Y., Sullivan, J., Wang, H., Yang, J., Shen, Y., Rubio, V., Ma, L., Hoecker, U. and Deng, X. (2003). The COP1-SPA1 interaction defines a critical step in phytochrome A-mediated regulation of HY5 activity. Genes & Development, 17(21), pp. 2642-2647.

Baumgardt, R., Oliverio, K., Casa, J. and Hoecker, U. (2002). SPA1, a component of phytochrome A signal transduction, regulates the light signaling current. Planta, 215(5), pp. 745-753.

Hoecker, U. and Quail, P. (2001). The phytochrome A-specific signaling intermediate SPA1 interacts directly with COP1, a constitutive repressor of light signaling in Arabidopsis. Journal of Biological Chemistry, 276(41), pp. 38173-38178.

Parks, B., Hoecker, U. and Spalding, E. (2001). Light-induced growth promotion by SPA1 counteracts phytochrome-mediated growth inhibition during de-etiolation. Plant Physiology, 126(3), pp. 1291-1298.

Hoecker, U., Tepperman, J. and Quail, P. (1999). SPA1, a WD-repeat protein specific to phytochrome A signal transduction. Science, 284(5413), pp. 496-499.

Hoecker, U., Vasil, I. and McCarty, D. (1999). Signaling from the embryo conditions Vp1-mediated repression of alpha-amylase genes in the aleurone of developing maize seeds. Plant Journal, 19(4), pp. 371-377.

Hoecker, U., Xu, Y. and Quail, P. (1998). SPA1: A new genetic locus involved in phytochrome A - Specific signal transduction. Plant Cell, 10(1), pp. 19-33.

Hoecker, U. and Quail, P. (1997). The phytochrome family of photoreceptors. European Journal of Cell Biology, 72, pp. 2-2.

Wagner, D., Hoecker, U. and Quail, P. (1997). RED1 is necessary for phytochrome B-mediated red light-specific signal transduction in Arabidopsis. Plant Cell, 9(5), pp. 731-743.

Hoecker, U., Vasil, I. and Mccarty, D. (1995). Integrated Control of Seed Maturation and Germination Programs by Activator and Repressor Functions of Viviparous-1 of Maize. Genes & Development, 9(20), pp. 2459-2469.

Hoecker, U., Rosenkrans, L., Vasil, I. and Mccarty, D. (1993). Vp1 Is a Repressor as Well as an Activator of Transcription in the Developing Seed. Journal of Cellular Biochemistry,, pp. 29-29.

Mccarty, D., Hoecker, U., Rosenkrans, L., Carson, C., Vasil, V., Vasil, I. and Stoll, M. (1993). Structure and Evolution of the Regulatory Network Controlling Maturation of the Seed. Journal of Cellular Biochemistry,, pp. 10-10.