caa a22 4500 606209484 CHVBK 20210128101028.0 cr unu---uuuuu 210128e20150501xx s 000 0 eng 10.1007/s00425-015-2248-x doi (NATIONALLICENCE)springer-10.1007/s00425-015-2248-x Preferential damaging effects of limited magnesium bioavailability on photosystem I in Sulla carnosa plants [Elektronische Daten] [Nèjia Farhat, Alexander Ivanov, Marianna Krol, Mokded Rabhi, Abderrazak Smaoui, Chedly Abdelly, Norman Hüner] Main conclusion : Magnesium deficiency preferentially inhibits photosystem I rather than photosystem II in Sulla carnosa plants. The effects of magnesium (Mg2+) deficiency on growth, photosynthetic performance, pigment and polypeptide composition of chloroplast membranes were studied in the halophyte Sulla carnosa (Desf.), an annual legume endemic to Tunisia and Algeria. The results demonstrate a gradual decrease in biomass production with decreasing Mg2+ availability in the growth medium. The increase of Mg2+ deficiency was also associated with a decline of the net CO2 assimilation (Pn) in fully expanded leaves, a decrease in the amount of photosynthetic pigments, and an increase in the lipid peroxidation in plants exposed to decreased Mg2+ concentrations. Interestingly, while CO2 assimilation already was affected at Mg2+ concentrations below 1.5mM, the photochemical efficiency of photosystem II (PSII) declined only in the absence of Mg2+. In contrast, plants of S. carnosa grown in Mg2+-deficient conditions exhibited a significant decrease in photosystem I (PSI) photochemistry in vivo at much higher Mg2+ levels compared to PSII photochemical activity. The inhibitory effect of Mg2+ deficiency on PSI photochemistry strongly correlated with significantly lower relative abundance of PSI-related chlorophyll-protein complexes and lower amounts of PSI-associated polypeptides, PsaA, PsaB, and Lhca proteins within the same range of Mg2+ concentrations. These observations were associated with a higher intersystem electron pool size, restricted linear electron transport and a lower rate of reduction of P700+ in the dark indicating restricted capacity for PSI cyclic electron transfer in plants exposed to Mg2+-deficient conditions compared to controls. These results clearly indicate that PSI, rather than PSII is preferentially targeted and damaged under Mg2+-deficiency conditions. Springer-Verlag Berlin Heidelberg, 2015 Chlorophyll-protein complexes nationallicence Electron transport nationallicence Photosynthesis nationallicence P700 redox state nationallicence AL : Actinic light nationallicence Car : Carotenoids nationallicence Chl : Chlorophyll nationallicence C i : Intercellular CO2 concentration nationallicence E : Transpiration nationallicence ETR : Electron transport rate nationallicence F m : Maximal chlorophyll fluorescence in dark-adapted state nationallicence $$ F_{\text{m}}^{\prime } $$ F m ′ : Maximal chlorophyll fluorescence in light-adapted state nationallicence F o : Minimal chlorophyll fluorescence in dark-adapted state nationallicence $$ F_{\text{o}}^{\prime } $$ F o ′ : Minimal chlorophyll fluorescence in light-adapted state nationallicence F v : Variable chlorophyll fluorescence in dark-adapted state nationallicence F v/ F m : Maximal quantum efficiency of PSII nationallicence ΦPSII : Effective quantum yield of PSII electron transport nationallicence FR : Far-red nationallicence gs : Stomatal conductance nationallicence MDA : Malonyldialdehyde nationallicence MT : Multiple-turnover flash nationallicence qN : Non-photochemical quenching coefficient nationallicence qP : Photochemical quenching coefficient nationallicence P700 : Reaction center pigment of PSI nationallicence P700+ : Oxidized form of the reaction center of PSI nationallicence PAR : Photosynthetically active radiation nationallicence Pn : Net CO2 assimilation nationallicence PS : Photosystem nationallicence ST : Single-turnover flash nationallicence WUE : Water use efficiency nationallicence Farhat Nèjia Laboratory of Extremophile Plants, Biotechnology Centre of Borj-Cedria, P. O. Box 901, 2050, Hammam-Lif, Tunisia aut Ivanov Alexander Department of Biology, University of Western Ontario, 1151 Richmond Street N., N6A 5B7, London, ON, Canada aut Krol Marianna Department of Biology, University of Western Ontario, 1151 Richmond Street N., N6A 5B7, London, ON, Canada aut Rabhi Mokded Laboratory of Extremophile Plants, Biotechnology Centre of Borj-Cedria, P. O. Box 901, 2050, Hammam-Lif, Tunisia aut Smaoui Abderrazak Laboratory of Extremophile Plants, Biotechnology Centre of Borj-Cedria, P. O. Box 901, 2050, Hammam-Lif, Tunisia aut Abdelly Chedly Laboratory of Extremophile Plants, Biotechnology Centre of Borj-Cedria, P. O. Box 901, 2050, Hammam-Lif, Tunisia aut Hüner Norman Department of Biology, University of Western Ontario, 1151 Richmond Street N., N6A 5B7, London, ON, Canada aut Planta Springer Berlin Heidelberg 241/5(2015-05-01), 1189-1206 0032-0935 241:5<1189 2015 241 425 https://doi.org/10.1007/s00425-015-2248-x text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00425-015-2248-x text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Farhat Nèjia Laboratory of Extremophile Plants, Biotechnology Centre of Borj-Cedria, P. O. Box 901, 2050, Hammam-Lif, Tunisia aut NATIONALLICENCE 700 1- Ivanov Alexander Department of Biology, University of Western Ontario, 1151 Richmond Street N., N6A 5B7, London, ON, Canada aut NATIONALLICENCE 700 1- Krol Marianna Department of Biology, University of Western Ontario, 1151 Richmond Street N., N6A 5B7, London, ON, Canada aut NATIONALLICENCE 700 1- Rabhi Mokded Laboratory of Extremophile Plants, Biotechnology Centre of Borj-Cedria, P. O. Box 901, 2050, Hammam-Lif, Tunisia aut NATIONALLICENCE 700 1- Smaoui Abderrazak Laboratory of Extremophile Plants, Biotechnology Centre of Borj-Cedria, P. O. Box 901, 2050, Hammam-Lif, Tunisia aut NATIONALLICENCE 700 1- Abdelly Chedly Laboratory of Extremophile Plants, Biotechnology Centre of Borj-Cedria, P. O. Box 901, 2050, Hammam-Lif, Tunisia aut NATIONALLICENCE 700 1- Hüner Norman Department of Biology, University of Western Ontario, 1151 Richmond Street N., N6A 5B7, London, ON, Canada aut NATIONALLICENCE 773 0- Planta Springer Berlin Heidelberg 241/5(2015-05-01), 1189-1206 0032-0935 241:5<1189 2015 241 425