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Sie sind hier: FRIAS School of Life Sciences … Fellows Ferenc Nagy

Ferenc Nagy

External Senior Fellow
August 2008 - July 2009

Institute of Plant Biology
Biological Research Center
Temesvari krt. 62
6726 Szeged
Hungary

Tel. +36 62 599-600 ext.: 718

CV

Ferenc Nagy is a professor of biology at the Institute of Plant Biology, Biological Research Centre (BRC) of the Hungarian Academy of Sciences. He studied biochemistry and genetics at the József Attila University in Szeged, Hungary, and after receiving his PhD in 1981, worked as a research scientist at the BRC. From 1983 to 1986 he continued his postdoctoral work as a fellow at the Laboratory of Plant Molecular Biology of the Rockefeller University, New York, USA, where he subsequently worked as an assistant professor for one year until 1987. Afterwards, Nagy continued his work at the BRC, as well as at the Friedrich-Miescher Institute at Basel, Switzerland, as a group leader. In 1997 he received his Doctor of Sciences from the Hungarian Academy of Sciences, Budapest. In 1998 he became deputy director of the BCR and in 2000 general director of the Agricultural Biotechnology Center, Gödöllő, Hungary. One year later, Nagy completed his habilitation at the Eötvös Loránd University of Sciences, Budapest, Hungary and becamea  member of the scientific board of the Max Planck International Research School, Cologne, Germany. In 2004 Nagy became an honorary professor of the Albert-Ludwigs University, Freiburg, and in 2006 once again he renewed an appointment as deputy director of the BCR. He is currently a guest professor at the University of Edinburgh. In 2008 he began work as a senior fellow at the School of Life Sciences – LIFENET of the newly founded institute, FRIAS, Freiburg Institute for Advanced Studies. Nagy has been and continues to be a board member of numerous national and international foundations, programmes and committees such as, the Hungarian UNESCO Committee for Art and Science, the International Society for Plant Molecular Biology (ISPBM). He is an elected member of EMBO, the German Academy of Sciences and an elected Council Member of EMBO, as well as a member of the Plant Biology Committee of the Hungarian Academy of Sciences. Ferenc Nagy has been distinguished by several awards, both nationally and internationally. In 1997 he was awarded the Humboldt Research Award. He held the Wolfgang Paul Research Award in 2001 and the Academy Award of the Hungarian Academy of Sciences in 2004, followed in 2005 by the Bela Tanko Award of the Hungarian Society of Biochemists. In 2008 he received the Szechenyi Award of the Republic of Hungary.

 

 

Qualitative and quantitative characterisation of ultraviolet-light induced signalling  cascades in Arabidopsis thaliana suspension culture cells

 

Project Background

Sunlight is of utmost importance to plants, both as the ultimate energy source and as an environmental signal regulating growth and development. For the latter, higher plants possess several classes of photoreceptors, including the molecularly known phytochromes for the red/far-red, and cryptochromes and phototropins for the UV-A/blue part of the spectrum. Ultraviolet-B (UVB; 280-315 nm) radiation is an integral part of the sunlight reaching the surface of the Earth and induces a broad range of physiological . Plants are able to respond to UV-B damage as well as to perceive UV-B specifically These UV-B-induced photomorphogenic responses are thought to be mediated by a UV-B-specific photoreceptor independent of known receptors for the visible part of the light spectrum (Safrany et al., 2008).  Factors involved in the UV-B-induced photomorphogenic pathway, such as the bZIP transcription factor ELONGATED HYPOCOTYL 5 (HY5) (Ulm et al., 2004), the E3 ubiquitin ligase CONSTITUTIVELY PHOTOMORPHOGENIC 1 (COP1) (Oravecz et al., 2006) and the putative guanine nucleotide exchange factor (GEF) similar to human RCC1 UV RESPONSE LOCUS 8 (UVR8), all display reduced tolerance to UV-B stress (d). Despite these considerable advances our knowledge about the molecular identity of the putative UV-B receptor and precise molecular mechanisms by which UV-B regulates expression of a large number of genes remains relatively poor.

 


Relevant publications:

  1. Ulm, R., Baumann, A., Oravecz, A., Mate, Z., Adam, E., Oakeley, J., Schafer, E., Nagy, F. (2004) Genome-wide analysis of gene expression reveals HY5 function in the UV-B response of Arabidopsis. Proc. Natl. Acad. Sci. USA 101, 1397-1402
  2. Ulm, R., Nagy, F. (2005) Signalling and gene regulation in response to ultraviolet light. Curr. Opin. Plant Biol. 8, 477-482.
  3. Oravecz, A., Baumann, A., Máté, Z., Brzezinska, A., Molinier, J., Oakeley, E.J., Ádám, É., Schäfer, E., Nagy, F., Ulm, R. (2006)  CONSTITUTIVELY PHOTOMORPHOGENIC 1 is required for the UV-B response in Arabidopsis. The Plant Cell1 8,1975-1988.
  4. Sáfrány, J., Haasz, V., Máté, Z., Ciolfi, A., Fehér, B., Oravecz, A., Stec, A., Dallmann, G., Morelli, G., Ulm, R., Nagy, F. (2008) Identification of a novel cis-regulatory element for UV-B induced transcription in Arabidopsis. Plant J. 54, 402-414.
  5. A. Pfeiffer, T. Kunkel, A. Hiltbrunner, G. Neuhaus, I. Wolf, V. Speth, E. Adam, F. Nagy, E. Schäfer: A cell-free system for light-dependent nuclear import of Phytochrome Plant J, 2009; 57 (4): 680-689
  6. J.J. Favory, A. Stec, H. Gruber, L. Rizzini, A. Oravecz, M. Funk, A. Albert, C. Cloix, G. Jenkins, E. Oakeley, H. Seidlitz, F. Nagy, R. Ulm: Interaction of COP1 and UVR8 regulates UV-B-induced photomorphogenesis and stress acclimation in Arabidopsis The EMBO Journal, 2009; 28 (5): 591-601
  7. J. Rausenberger, A. Hussong, S. Kircher, D. Kirchenbauer, J. Timmer, F. Nagy, E. Schafer, C. Fleck: An Integrative Model for Phytochrome B Mediated Photomorphogenesis: From Protein Dynamics to Physiology Plos One, 2010; 5: e10721
  8. I. Wolf, S. Kircher, E. Fejes, L. Kozma-Bognar, E. Schafer, F. Nagy, E. Adam: Light-Regulated Nuclear Import and Degradation of Arabidopsis Phytochrome-A N-Terminal Fragments Plant and Cell Physiology, 2011; 52 (2): 361-372
  9. L. Rizzini, J.J. Favory, C. Cloix, D. Faggionato, A. O'Hara, E. Kaiserli, R. Baumeister, E. Schafer, F. Nagy, G.I. Jenkins, R. Ulm: Perception of UV-B by the Arabidopsis UVR8 Protein Science, 2011; 332 (6025): 103-106

 

Project Description

Identification and characterisation of specific mutant plants displaying aberrant UV-B responsiveness and/or production of custom-made transgenic lines suitable for detailed analysis of UV-B perception, signalling are effective but very time and energy consuming processes. To accelerate discovery of key molecular components and mechanisms mediating UV-B induced physiological responses we propose to use Arabidopsis cell suspension cultures as alternative experimental systems. In contrast to intact Arabidopsis plants, suspension cultures are uniform, easily maintained and multiplied and are amenable for biochemical studies. Suspension cultures can easily be transformed and selection, maintenance of stable transgenic suspension cultures is  a well-established process in our laboratory. To test specifically to what extent UV-B responsiveness of Arabidopsis suspension cultures are identical with that of displayed by major, developed plants we propose to perform the following research program that contains 2 work packages (WP).

 

Work Package P 1

To compare UV-B responsiveness of selected genes in wild type suspension cultures and mature plants

Duration: 0-6 months

Task 1. We will establish stable transgenic suspension cultures expressing (a) the HY-5/LUC reporter gene (expression of this reporter is induced by low fluence rate, long wavelength UV-B), (b) the ANAC13/LUC reporter gene (expression of this reporter is induced by high fluence rate, long wavelength UV-B) and (c) P17/LUC reporter (expression of this reporter is induced by unfiltered, short wavelength UV light).

Task 2. We characterise and compare UV inducibility of the endogenous HY-5, ANAC13 and P17 genes and the above described transgenes in suspension cultures and mature, developed Arabidopsis plants by real-time PCR, in vivo bioluminescence imaging and micro-array analysis.

 

Work Package P 2

To establish stable, custom-designed transgenic suspension cultures to study effects of loss of function mutations on UV induced signalling

Duration: 6-12 months

Task 1. Artificial micro RNAs (ami RNA) and RNAi mediated gene silencing have been shown  to be effective methods to alter gene expression levels and produce loss of function (LOF) mutants in Arabidopsis. To test to what extent these approaches will be useful to create LOF mutants in suspension cultures we will produce stably transformed transgenic suspension culture lines expressing specific amiRNAs and RNAi targeting key regulatory components of UV-B induced signalling, COP1 and UVR8 genes, respectively.

Task 2. To compare efficiency of these methods we will characterise UV-B responsiveness of selected genes in transgenic LOF plants and suspension culture lines by real-time PCR, in vivo bioluminescence imaging and micro-array analysis.

Task 3. Completion of WP1 and 2 will allow us to establish optimal experimental conditions for high through-put screens for identifying additional components of UV induced signalling


Remarks:

The research program in the Institute of Botany aimed at identifying key regulatory components of UV-B induced signalling was initiated by Ferenc Nagy after receiving the Wolfgang Paul Award in 2001. He established  a new research group, recruited a number of talented young researcher including Dr. Roman Ulm and led this program until 2004. In 2005 Dr. Roman Ulm won the Emmy Noeter Fellowship established himself as the new head of the group and developed his own research program on this subject. After 2005 Professor Nagy and Dr. Ulm has established a close collaboration and the presented research proposal is complementary to the research program being carried out by the Ulm group in the Institute of Botany.