in English
Cross-talk between light acclimation and defence reactions in plants

Contact information

Saijaliisa Kangasjärvi
e-mail: saijaliisa.kangasjarvi [at]


Saijaliisa Kangasjärvi, Dr, Docent, Senior Lecturer, Project Leader
Guido Durian,  Dr., Postdoctoral Researcher
Jesus Pascual, Dr., Postdoctoral Researcher
Moona Rahikainen, Dr., Postdoctoral Researcher
Sara Alegre Garcia, MSc, Doctoral Student
Zsofia Winter, MSc
Challenge. Food security poses a major challenge for the growing world population, and urgently depends on disease-resistant crops with high post-harvest quality and yield. Plant resistance to pathogens essentially relies on mechanisms that sense, signal and respond to infection, but the molecular mechanisms that execute the defensive measures still remain a major biological question to be resolved.
Opportunity. During the evolutionary arms race, plants have evolved an amazing diversity of species-specific specialized metabolites, also called secondary metabolites, which act as chemical defenses to prevent pathogens and pests from colonizing host plant tissues. Notably, such plant-derived natural compounds offer significant medicinal, health-promoting and sensory properties for mankind.
Aims. The overall aim of our research is to elucidate molecular mechanisms of stress resistance in plants. Special attention is paid for light-dependent regulation of defensive measures, notably the formation of deterring secondary metabolites and their applicability in nutrition and medicine.
Approaches. Molecular genetic toolboxes for the model plant Arabidopsis thaliana and other cruciferous plants, together with recent developments in proteomics and live-cell imaging now make it possible to construct high resolution regulatory networks of specialized metabolism in plants. 
Gain. Increased understanding of plant chemical defenses may provide novel medicinal compounds as well as invaluable new strategies to evade future threats for food security.

Metabolic regulation in plant immunity (Funded by the Academy of Finland 2017-2021)

• Trans-methylation reactions are vital in basic metabolism, epigenetic regulation and biosynthesis of complex chemical compounds in all living organisms, but regulatory actions governing methyl utilization remain poorly understood.
• We address post-translational regulation of the activated methyl cycle and its critical role in determining methyl utilization in stress-exposed plants.
• More specifically, we focus on regulatory actions of protein phosphatase 2A on the activated methyl cycle and the associated biosynthesis of deterring secondary metabolites in pathogen-infected leaves.
• Genetic toolboxes for Arabidopsis thaliana, together with selected reaction monitoring mass spectrometry, metabolomics and live-cell imaging are utilized to decipher the metabolic and regulatory networks.
• This will advance our understanding of regulatory networks linking primary and secondary metabolism at the post-translational level, which will be an important consideration in future engineering of bio-fortified crops.

Interested in doing your Master’s thesis, PhD thesis or Post-doc with us?
Please contact

Recent publications

Rahikainen M, Alegre S, Trotta A, Pascual J, Kangasjärvi S. 2017. Trans-methylation reactions in plants: focus on the activated methyl cycle. Physiologia Plantarum, in press. [A2]  [Epub ahead of print]

Salojärvi J, Smolander OP, Nieminen K, Rajaraman S, Safronov O, Safdari P, Lamminmäki A, Immanen J, Lan T, Tanskanen J, Rastas P, Amiryousefi A, Jayaprakash B, Kammonen JI, Hagqvist R, Eswaran G, Ahonen VH, Serra JA, Asiegbu FO, de Dios Barajas-Lopez J, Blande D, Blokhina O, Blomster T, Broholm S, Brosché M, Cui F, Dardick C, Ehonen SE, Elomaa P, Escamez S, Fagerstedt KV, Fujii H, Gauthier A, Gollan PJ, Halimaa P, Heino PI, Himanen K, Hollender C, Kangasjärvi S, Kauppinen L, Kelleher CT, Kontunen-Soppela S, Koskinen JP, Kovalchuk A, Kärenlampi SO, Kärkönen AK, Lim KJ, Leppälä J, Macpherson L, Mikola J, Mouhu K, Mähönen AP, Niinemets Ü, Oksanen E, Overmyer K, Palva ET, Pazouki L, Pennanen V, Puhakainen T, Poczai P, Possen BJHM, Punkkinen M, Rahikainen MM, Rousi M, Ruonala R, van der Schoot C, Shapiguzov A, Sierla M, Sipilä TP, Sutela S, Teeri TH, Tervahauta AI, Vaattovaara A, Vahala J, Vetchinnikova L, Welling A, Wrzaczek M, Xu E, Paulin LG, Schulman AH, Lascoux M, Albert VA, Auvinen P, Helariutta Y, Kangasjärvi J. (2017) Genome sequencing and population genomic analyses provide insights into the adaptive landscape of silver birch. Nat Genet. 49(6): 904-912 [A1]
Jakobson, L.; Vaahtera, L.; Tõldsepp, K.; Nuhkat, M.; Wang, C.; Wang, YS.; Hõrak, H.; Valk, E.; Pechter, P.; Sindarovska, Y.; Tang, J.; Xiao, C.; Xu, Y.; Gerst Talas, U.; García-Sosa, AT.; Kangasjärvi, S.; Maran, U.; Remm, M.; Roelfsema, MR.; Hu, H.; Kangasjärvi, J.; Loog, M.; Schroeder, JI.; Kollist, H. & Brosché M. 2016:  Natural variation in Arabidopsis Cvi-0 accession reveals an important role of MPK12 in guard cell CO2 signaling. - PLOS BIOLOGY 14(12): e2000322   [A1]
Rahikainen, M.; Trotta, A.; Alegre, S.; Pascual, J.; Vuorinen, K.; Overmyer, K.; Moffatt, B.; Ravanel, S.; Glawischnig, E., &, Kangasjärvi, S. 2016:  PP2A-B'γ modulates foliar trans-methylation capacity and formation of 4-methoxy-indol-3-yl-methyl glucosinolate in Arabidopsis leaves. -THE PLANT JOURNAL 89(1): 112-127.  (Epub 2016 Sep 6).
Durian, G.; Rahikainen, M.; Alegre García, S.; Brosché*, M. & Kangasjärvi, S. 2016:  Protein Phosphatase 2A in the regulatory network underlying biotic stress resistance in plants. - FRONTIERS IN PLANT SCIENCE 7(812): 1-17.   Free article   (Epub 2016 Jun 10).
Rahikainen, M.; Pascual, J.; Alegre, S.; Durian, G: & Kangasjärvi, S. 2016:  PP2A phosphatase as a regulator of ROS signaling in plants. - ANTIOXIDANTS 5(1): 8 11 pp.   Free article   (Epub 2016 Mar 2).
Allahverdiyeva, Y.; Battchikova, N.; Brosché, M.; Fujii, H.; Kangasjärvi, S.; Mulo, P.; Mähönen, AP.; Nieminen*, K.; Overmyer, K.; Salojärvi J. & Wrzaczek, M. 2015:  Integration of photosynthesis, development and stress as an opportunity for plant biology. - NEW PHYTOLOGIST 208(3): 647-655.  Free article    (Epub 2015 Jul 14).
Konert, G.; Rahikainen, M.; Trotta, A.; Durian, G.; Salojärvi J, Khorobrykh S, Tyystjärvi E, Kangasjärvi S. 2015:  Subunits B'γ and B'ζ of Protein Phosphatase 2A regulate photo-oxidative stress responses and growth in Arabidopsis thaliana. - PLANT, CELL & ENVIRONMENT 38(12): 2641-2651).   (Epub 2015 May 27).
Konert, G.; Trotta, A.; Kouvonen*, P.; Rahikainen, M.; Durian, G.; Blokhina*, O.; Fagerstedt*, K.; Muth*, D.; Corthals*, GL. & Kangasjärvi S. 2014:  Protein phosphatase 2A (PP2A) regulatory subunit B'γ interacts with cytoplasmic ACONITASE 3 and modulates the abundance of AOX1A and AOX1D in Arabidopsis thaliana. - NEW PHYTOLOGIST 205(3): 1250-1263.   (Epub 2014 Oct 13).
Rasool*, B.; Karpinska*, B.; Konert, G.; Durian, G.; Denessiouk*, K.; Kangasjärvi, S. & Foyer, CH. 2014:  Effects of light and the regulatory B-subunit composition of protein phosphatase 2A on the susceptibility of Arabidopsis thaliana to aphid (Myzus persicae) infestation. - FRONTIERS IN PLANT SCIENCE 5(405): 1-11.   Free article   (Epub 2014 Aug 21).
Casanova-Sáez*, R.; Mateo-Bonmatí*, E.; Kangasjärvi, S.; Candela*, H. & Micol*,  JL. 2014:  Arabidopsis ANGULATA10 is required for thylakoid biogenesis and mesophyll development. - JOURNAL OF EXPERIMENTAL BOTANY 65(9): 2391-2404.  Free article  (Epub 2014 Mar 24).
Kangasjärvi, S. & Kangasjärvi*, J. 2014:  Towards understanding extracellular ROS sensory and signaling systems in plants. - ADVANCES IN BOTANY 2014, Article ID 538946: 1-10.  Free article   (Epub 2014 Jun 1). 
Kangasjärvi, S.; Tikkanen, M.; Durian, G. & Aro, EM. 2014:  Photosynthetic light reactions – An adjustable hub in basic production and plant immunity signaling. - PLANT PHYSIOLOGY AND BIOCHEMISTRY 81: 128-134.   (Epub 2013 Dec 14).
Li*, S.; Mhamdi*, A.; Trotta, A.; Kangasjärvi, S. & Noctor*, G. 2014:  The protein phosphatase subunit PP2A-B'γ is required to suppress day length-dependent pathogenesis responses triggered by intracellular oxidative stress. - NEW PHYTOLOGIST 202(1): 145-160.   (Epub 2013 Dec 2).
Trotta, A.; Rahikainen, M.; Konert, G.; Finazzi*, G. & Kangasjärvi, S. 2014:  Signalling crosstalk in light stress and immune reactions in plants. - PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY B 369(1640): 20130235   (Epub 2014 Mar 3).
Heidari*, B.; Nemie-Feyissa*, D.; Kangasjärvi, S. & Lillo*, C. 2013:  Antagonistic regulation of flowering time through distinct regulatory subunits of protein phosphatase 2A. -  PLoS ONE 8(7): e67987.
Pérez-Pérez*, JM.; Esteve-Bruna*, D.; González-Bayón*, R.; Kangasjärvi, S.; Caldana*, C.; Hannah*, MA.; Willmitzer*, L.; Ponce*, MR. & Micol*, JL. 2013:  Functional redundancy and divergence within the Arabidopsis RETICULATA-RELATED gene family. - PLANT PHYSIOLOGY 162(2): 589-603.​1104/​pp.​113.​217323   Free article
Suorsa, M.; Grieco, M.; Järvi, S.; Gollan, PJ.; Kangasjärvi, S.; Tikkanen, M. & Aro, EM. 2013: PGR5 ensures photosynthetic control to safeguard photosystem I under fluctuating light conditions. -  PLANT SIGNALLING BEHAVIOR 8(1): 1-6.
Sierla*, M.; Rahikainen, M.; Salojärvi*, J.; Kangasjärvi*, J. & Kangasjärvi, S. 2013:  Apoplastic and chloroplastic redox signaling networks in plant stress responses. - ANTIOXIDANTS & REDOX SIGNALING 18(16): 2220-2239.
Grouneva, I.; Gollan, PJ.; Kangasjärvi, S.; Suorsa, M.; Tikkanen, M. & Aro, EM. 2013:  Phylogenetic viewpoints on regulation of light harvesting and electron transport in eukaryotic photosynthetic organisms. - PLANTA 237(2): 399-412.
Suorsa, M.; Järvi, S.; Grieco, M.; Nurmi, M.; Pietrzykowska*, M.; Rantala, M.; Kangasjärvi, S.; Paakkarinen, V.; Tikkanen, M.; Jansson*, S. & Aro, EM. 2012:  PROTON GRADIENT REGULATION5 is essential for proper acclimation of Arabidopsis Photosystem I to naturally and artificially fluctuating light conditions. - PLANT CELL 24(7): 2934-2948.
Tikkanen, M.;  Gollan, P.; Suorsa, M.; Kangasjärvi, S. &  Aro, EM. 2012:  STN7 operates in retrograde signaling through controlling redox balance in the electron transfer chain. - FRONTIERS IN PLANT PHYSIOLOGY 3(277): 1-11.   Free article
Grieco, M.; Tikkanen, M.; Paakkarinen, V.; Kangasjärvi, S. & Aro, EM. 2012:  Steady-state phosphorylation of light-harvesting complex II proteins preserves Photosystem I under fluctuating white light. - PLANT PHYSIOLOGY 160(4): 1896-1910.   Free Article
Hebbelmann*, I.; Selinski*, J.; Wehmeyer*, C.; Goss*, T.; Voss*, I.; Mulo, P.; Kangasjärvi, S.; Aro, EM.; Oelze*, ML.; Dietz*, KJ.; Nunes-Nesi*, A.; Do*, PT.; Fernie*, AR.; Talla*, SK.; Raghavendra*, AS.; Linke*, V. & Scheibe*, R. 2012:  Multiple strategies to prevent oxidative stress in Arabidopsis plants lacking the malate valve enzyme NADP-malate dehydrogenase. - JOURNAL OF EXPERIMENTAL BOTANY 63(3): 1445-1459.  Free article
Kangasjärvi, S.; Neukermans*, J.; Li, S.; Aro, EM. & Noctor*, G. 2012: Photosynthesis, photorespiration, and light signalling in defence responses. - JOURNAL OF EXPERIMENTAL BOTANY  63(4): 1619-1636.
Trotta, A.; Konert, G.; Rahikainen, M.; Aro, EM. & Kangasjärvi, S. 2011:  Knock-down of protein phosphatase 2A subunit B'γ promotes phosphorylation of CALRETICULIN 1 in Arabidopsis thaliana. - PLANT SIGNALING AND BEHAVIOR 6(11):1665-1668.
Trotta, A.; Wrzaczek*, M.; Scharte*, J.; Tikkanen, M.; Konert, G.; Rahikainen, M.; Holmström, M.; Hiltunen, HM.; Rips*, S.; Sipari*, N.; Mulo, P.; Weis*, E.; von Schaewen*, A.; Aro, EM. & Kangasjarvi, S. 2011:  Regulatory subunit B'γ of protein phosphatase 2A prevents unnecessary defense reactions under low light in Arabidopsis thaliana. - PLANT PHYSIOLOGY 156(3):1464-1480   Free article
*Wrzaczek, M., *Brosche, M., *Salojärvi, J., Kangasjärvi, S., *Idänheimo, N., *Mersmann, S., *Robatzek, S., *Karpinski, S., *Karpinska, B., *Kangasjärvi, J. 2010:  Transcriptional regulation of the CRK/DUF26 group of Receptor-like protein kinases by ozone and plant hormones in Arabidopsis. - BMC PLANT BIOLOGY 10:95   Free article
Yin, L. Lundin, B. Bertrand, M. Nurmi, M., Solymosi, K., Kangasjärvi, S. Aro, E.-M., Schoefs, B.and Spetea, C. (2010) Role of Thylakoid ATP/ADP Carrier in Photoinhibition and Photoprotection of Photosystem II in Arabidopsis. PLANT PHYSIOLOGY 153(2): 666-677.   Free Article
Tikkanen, M., Grieco, M., Kangasjärvi, S. and Aro, E.-M. (2010): Thylakoid protein phosphorylation in higher plant chloroplasts optimises electron transfer under fluctuating light. PLANT PHYSIOLOGY 152(2): 723-735.   Free PMC Article
Broche, M., Overmyer, K., Wrzaczek, M., Kangasjärvi, J and Kangasjärvi, S. (2010) Stress signaling: reactive oxygen species. In: Bohnert, H., Govindjee, Pareek, A. and Sopory, S. (Eds.): Abiotic Stress Adaptation in Plants: Physiological, Molecular and Genomic Foundation (Springer, Dordrecht, The Netherlands), pp. 91-102. DOI: 10.1007/978-90-481-3112-9_5.
Rintamäki, E., Lepistö, A. and Kangasjärvi, S. (2009) Implication of chlorophyll biosynthesis on chloroplast-to-nucleus retrograde signaling. Plant Signaling & Behavior 4: 545-547.
Kangasjärvi, S., Nurmi, M., Tikkanen, M. and Aro, E.-M. (2009) Cell-specific mechanisms and systemic signalling as emerging themes in light acclimation of C3 plants. Plant Cell and Environment 32:1230-1240.
Lepistö A, Kangasjärvi S, Luomala EM, Brader G, Sipari N, Keranen M, Keinänen M, Rintamäki E (2009) Chloroplast NADPH Thioredoxin Reductase Interacts with Photoperiodic Development in Arabidopsis thaliana. Plant Physiology 149:1261-1276.
Tikkanen, M., Nurmi, M., Kangasjärvi, S. and Aro, E.-M. (2008) Core protein phosphorylation facilitates the repair of photodamaged photosystem II at high light. Biochimical and Biophysical Acta. 1777:1432-1437.
Lintala M, Allahverdiyeva Y, Kangasjärvi S, Lehtimäki N, Keränen M, Rintamäki E, Aro EM, Mulo P. (2009): Comparative analysis of leaf-type ferredoxin-NADP(+)-oxidoreductase isoforms in Arabidopsis thaliana. Plant J 57:1103-1115.
Overmyer, K., Kollist, H.,  Tuominen, H., Betz, C., Langebartels, C, Wingsle, G., Kangasjärvi, S., Brader, G., Mullineaux, P., and Kangasjärvi, J (2008) Complex phenotypic profiles leading to ozone sensitivity in Arabidopsis thaliana mutants. Plant Cell and Environment 31: 1237-1249.
Kangasjärvi, S, Lepistö, A, Hännikäinen, K., Luomala, E.-M., Aro, E.-M. and Rintamäki, E. (2008) Dissection of the role of chloroplast stromal and thylakoid-bound ascorbate peroxidases in plant stress responses. Biochemical Journal 412:275-285.