Laboratorium Fotobiologii

Łabuz Justyna, dr, kierownik grupy,, (+48 12) 664 6109

Banaś Agnieszka Katarzyna, dr,, (+48 12) 664 6410
Bażant Aneta, mgr,, (+48 12) 664 6109
Hermanowicz Paweł, mgr,, (+48 12) 664 6347
Kozłowska Anna, mgr inż.,, (+48 12) 664 6109
Zgłobicki Piotr, mgr,, (+48 12) 664 6109

Research areas

The main area of research is photobiology, in particular the impact of blue light on plants physiology. Fig1. Chloroplast localization of a putative photolyase.Our studies concentrate on phototropins. These UVA/blue light photoreceptors mediate processes which fine tune photosynthesis, including chloroplast movements, phototropism, stomatal opening, leaf positioning and blade formation. Phototropins contain two flavin mononucleotides as chromophores in the photo-sensory LOV (Light, Oxygen and Voltage) domains at the N-terminus and a Ser/Thr kinase domain at the C-terminus. Two phototropins (phototropin1 and phototropin2) are encoded in the genome of the model plant Arabidopsis thaliana. They share highly redundant functions, however some processes are controlled solely by one phototropin. Chloroplast movements in response to light depend on light intensity. Low light induces the chloroplast accumulation response, which is controlled by both phototropin1 and phototropin2. High light induces chloroplast avoidance. Only phototropin2 can trigger full avoidance. Fig2. Nuclear localization of UVR3.Phototropin1 can elicit only a residual avoidance response. Thus, phototropins can change their signaling outcomes according to the light intensity. Light down-regulates the level of phototropin1, while it up-regulates the phototropin2 level. Phototropins can form homo- and heterodimers. Dimerization seems to modify their signaling outcomes. The physiological importance of the regulation of phototropin expression and activity is still poorly understood. The molecular basis for the difference in the signaling pathways leading to chloroplast movements in low and high light remains unknown. Differences in the structures of phototropin1 and phototropin2 may determine their ability of changing the pathways from chloroplast accumulation into avoidance. Downstream signaling components: proteins phosphorylated by phototropins or secondary messengers such as phosphoinositides may also be responsible for the modulation of chloroplast responses to light.
Fig3. Membrane localization of phototropin2.The project currently carried out in MCB focuses on the mechanisms through which light controls phototropin expression in Arabidopsis thaliana. We study transcription factors that bind to phototropin promoters and investigate the involvement of post-transcriptional mechanisms in the regulation of phototropin expression.
The second topic investigated by our group is regulation of plant functioning by UVA/blue light and the properties of plant photolyases. Photolyases are enzymes involved in the direct repair of UVB-induced pyrimidine dimers in a blue light/UVA-dependent manner. This reaction is called photoreactivation. We study the subcellular localization of both well-known and putative Arabidopsis photolyases using proteins fused to fluorescent proteins. We also analyze the effects of visible and UV light on photolyase expression and activity.

Future plans

We plan to:

  • investigate the molecular basis of phototropin signaling leading to chloroplast movements, in particular the physiological relevance of phototropin dimerization.
  • elucidate the biological activity of well-known and putative Arabidopsis photolyases in terms of photoreactivation, chloroplast biogenesis, chloroplast DNA maintenance and plant responses to abiotic stresses. The impact of alternative splicing, sumoylation and phosphorylation on biological functions of these genes will be investigated.
  • start a cooperation with a commercial partner to develop photocatalytically active anti-foaming surfaces resistant to algae and moss growth.

2015 – 2018 – SONATA8, NCN, UMO-2014/15/D/NZ2/02306 “Light regulation of phototropin expression in Arabidopsis thaliana”, principle investigator: Justyna Łabuz
2014 - 2019 – SONATA BIS3 UMO-2013/10/E/NZ1/00749 "Characterizing the functions of plant PCNA1 and PCNA2 proteins using Arabidopsis thaliana as an experimental model", principle investigator: Wojciech Strzałka
2017 – 2022 – SONATA BIS6, NCN, UMO-2016/22/E/NZ3/00326, „ Arabidopsis photolyases: the role of post-transcriptional and post-translational modifications, influence on DNA repair, chloroplast functioning and plant responses to abiotic stresses.” principle investigator: Agnieszka Katarzyna Banaś

2018 – 2021 OPUS 13, Dissecting the molecular basis of phototropin signaling to chloroplast movements in Arabidopsis thaliana, principle investigator: Justyna Łabuz


Sztatelman O, Łabuz J, Hermanowicz P, Banaś AK, Bażant A, Zgłobicki P, Aggarwal C, Nadzieja M, Krzeszowiec W, Strzałka W, Gabryś H 2016. Fine tuning chloroplast movements through physical interactions between phototropins. Journal of Experimental Botany, 67, 4963-4978.
Łabuz J, Samardakiewicz S, Hermanowicz P, Wyroba E, Pilarska M, Gabryś H 2016. Blue light-dependent changes in loosely bound calcium in Arabidopsis mesophyll cells: an X-ray microanalysis study. Journal of Experimental Botany, 67, 3953-3964.
Eckstein A, Jagiełło-Flasińska D, Lewandowska A, Hermanowicz P, Appenroth K-J, Gabryś H 2016. Mobilization of storage materials during light-induced germination of tomato (Solanum lycopersicum) seeds. Plant Physiology and Biochemistry, 105, 271-281.
Sztatelman O, Grzyb J, Gabryś H, Banaś AK 2015. The effect of UV-B on Arabidopsis leaves depends on light conditions after treatment. BMC Plant Biology 15, 281.
Strzałka W, Aggarwal C, Krzeszowiec W, Jakubowska A, Sztatelman O, Banaś AK 2015. Arabidopsis PCNAs form complexes with selected D-type cyclins. Frontiers in Plant Science 6, 516.

Grzyb J, Gieczewska K, Łabuz J, Sztatelman O. 2018. Detailed characterization of Synechocystis PCC 6803 ferredoxin:NADP+ oxidoreductase interaction with model membranes. Biochimica et Biophysica Acta (BBA) - Biomembranes. 1860, 281-291 
Kowalska E, Bartnicki B, Fujisawa R, Bonarek P, Hermanowicz P, Tsurimoto T, Muszyńska K, Strzalka W. 2018. Inhibition of DNA replication by an anti-PCNA aptamer/PCNA complex. Nucleic Acids Research, gkx1184,
Banaś AK, Hermanowicz P, Sztatelman O, Łabuz J, Aggarwal Ch, Zgłobicki P, Jagiełło-Flasińska D, Strzałka W 2018. 6,4 - PP Photolyase Encoded by AtUVR3 is Localized in Nuclei, Chloroplasts and Mitochondria and Its Expression is Down-Regulated by Light in a Photosynthesis-Dependent Manner. Plant and Cell Physiology. pcx159,