Plastoquinone redox state modifies plant response to pathogen.
The role of PQ (plastoquinione) redox state in establishment of response to pathogen infection (Botrytis cinerea) was tested along the regulation of main antioxidative enzymes (superoxide dismutase - SOD, catalase - CAT) and photochemistry of PSII (photosystem II) in Mesembryanthemum crystallinum plants performing C3 and CAM (Crassulacean acid metabolism) carbon metabolism. The redox state of PQ was modified by two inhibitors of photosynthetic electron transport resulting in a more oxidised (3-(3,4-dichlorophenyl)-1,1-dimethylurea; DCMU) or reduced (2,5-dibromo-3-methyl-6-isopropyl-p-benzoquinone; DBMIB) PQ redox state simulating darkness and high light conditions, respectively. Irrespective of the type of treatment (mock inoculation or pathogen inoculation) SOD activity depended on the PQ pool. Our results suggest that regarding changes in infection-induced CAT activity, plants developed response that is vital for hypersensitive-like (HR-like) response establishment only when PQ pool generated signal was similar to that in light presence (DBMIB pre-treatment). When PQ pool generated signal was similar to darkness, CAT activity response remained stress-independent, similarly to SOD. Fluorescence parameters of PSII, Qp (photochemical quenching coefficient) and NPQ (non-photochemical quenching) were affected only in the tissues treated with DCMU in stress-independent manner. We suggest that in case of abiotic and biotic stresses signals emerging from PQ pool indirectly orchestrate plant response and carbon metabolism affects this regulatory pathway.
Institute of Biology, Pedagogical University, Podbrzezie 3, 31-054 Kraków, Poland.
Michał
M
Nosek
Institute of Biology, Pedagogical University, Podbrzezie 3, 31-054 Kraków, Poland.
Andrzej
A
Kornaś
Department of Plant Physiology and Biochemistry, Faculty of Biology and Environmental Protection, University of Lodz, Banacha 12/16, 90-237 Łódź, Poland.
Elżbieta
E
Kuźniak
Malopolska Centre of Biotechnology, Jagiellonian University, Gronostajowa 7a, 30-387 Kraków, Poland; Institute of Plant Physiology, Polish Academy of Sciences, Niezapominajek 21, 30-239 Kraków, Poland. Electronic address: zbigniew.miszalski@uj.edu.pl.
Zbigniew
Z
Miszalski
D002374:Catalase / Q000378:metabolism; D005453:Fluorescence; D054884:Host-Pathogen Interactions; D010084:Oxidation-Reduction; D018521:Plant Physiological Phenomena; D010971:Plastoquinone / Q000378:metabolism*; D013482:Superoxide Dismutase / Q000378:metabolism
D002374:Catalase; D013482:Superoxide Dismutase; D010971:Plastoquinone
Antioxidative enzymes; Botrytis cinerea; C(3); CAM; DBMIB; DCMU; Mesembryanthemum crystallinum