{"type": "FeatureCollection", "features": [{"id": "10.1093/jxb/erq249", "type": "Feature", "geometry": null, "properties": {"updated": "2026-09-20T16:17:16Z", "type": "Journal Article", "created": "2010-08-27", "title": "Plant Physiology And Proteomics Reveals The Leaf Response To Drought In Alfalfa (Medicago Sativa L.)", "description": "Despite its relevance, protein regulation, metabolic adjustment, and the physiological status of plants under drought is not well understood in relation to the role of nitrogen fixation in nodules. In this study, nodulated alfalfa plants were exposed to drought conditions. The study determined the physiological, metabolic, and proteomic processes involved in photosynthetic inhibition in relation to the decrease in nitrogenase (N(ase)) activity. The deleterious effect of drought on alfalfa performance was targeted towards photosynthesis and N(ase) activity. At the leaf level, photosynthetic inhibition was mainly caused by the inhibition of Rubisco. The proteomic profile and physiological measurements revealed that the reduced carboxylation capacity of droughted plants was related to limitations in Rubisco protein content, activation state, and RuBP regeneration. Drought also decreased amino acid content such as asparagine, and glutamic acid, and Rubisco protein content indicating that N availability limitations were caused by N(ase) activity inhibition. In this context, drought induced the decrease in Rubisco binding protein content at the leaf level and proteases were up-regulated so as to degrade Rubisco protein. This degradation enabled the reallocation of the Rubisco-derived N to the synthesis of amino acids with osmoregulant capacity. Rubisco degradation under drought conditions was induced so as to remobilize Rubisco-derived N to compensate for the decrease in N associated with N(ase) inhibition. Metabolic analyses showed that droughted plants increased amino acid (proline, a major compound involved in osmotic regulation) and soluble sugar (D-pinitol) levels to contribute towards the decrease in osmotic potential (\u03a8(s)). At the nodule level, drought had an inhibitory effect on N(ase) activity. This decrease in N(ase) activity was not induced by substrate shortage, as reflected by an increase in total soluble sugars (TSS) in the nodules. Proline accumulation in the nodule could also be associated with an osmoregulatory response to drought and might function as a protective agent against ROS. In droughted nodules, the decrease in N(2) fixation was caused by an increase in oxygen resistance that was induced in the nodule. This was a mechanism to avoid oxidative damage associated with reduced respiration activity and the consequent increase in oxygen content. This study highlighted that even though drought had a direct effect on leaves, the deleterious effects of drought on nodules also conditioned leaf responsiveness.", "keywords": ["Proteomics", "0301 basic medicine", "570", "Rubisco", "Proteome", "[SDV]Life Sciences [q-bio]", "proteome", "N-2 FIXATION RESPONSE", "drought", "N2 fixation", "03 medical and health sciences", "XANTHOPHYLL CYCLE", "N-2 fixation", "2-CYSTEINE PEROXIREDOXIN", "Nitrogenase", "oxidative stress", "AMINO-ACIDS", "Photosynthesis", "climate", "agriculture", "Plant Proteins", "580", "N remobilization", "2. Zero hunger", "0303 health sciences", "photosynthesis", "PINITOL ACCUMULATION", "Drought", "RIBULOSE-1", "5-BISPHOSPHATE CARBOXYLASE-OXYGENASE", "Water", "BRASSICA-NAPUS", "N(O)-TERT-BUTYLDIMETHYLSILYL DERIVATIVES", "15. Life on land", "Research Papers", "6. Clean water", "Droughts", "[SDV] Life Sciences [q-bio]", "Plant Leaves", "nitrogen fixation", "Oxidative stress", "rubisco", "NITROGEN-FIXATION", "WATER-WATER CYCLE", "Medicago sativa"]}, "links": [{"href": "https://doi.org/10.1093/jxb/erq249"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Journal%20of%20Experimental%20Botany", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1093/jxb/erq249", "name": "item", "description": "10.1093/jxb/erq249", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1093/jxb/erq249"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2010-08-25T00:00:00Z"}}, {"id": "10.1111/j.1365-3040.2004.01231.x", "type": "Feature", "geometry": null, "properties": {"updated": "2026-09-20T16:17:39Z", "type": "Journal Article", "created": "2004-10-06", "title": "Functional Diversity Of Photosynthesis During Drought In A Model Tropical Rainforest - The Contributions Of Leaf Area, Photosynthetic Electron Transport And Stomatal Conductance To Reduction In Net Ecosystem Carbon Exchange", "description": "ABSTRACT<p>The tropical rainforest mesocosm within the Biosphere 2 Laboratory, a model system of some 110 species developed over 12\uffe2\uff80\uff83years under controlled environmental conditions, has been subjected to a series of comparable drought experiments during 2000\uffe2\uff80\uff932002. In each study, the mesocosm was subjected to a 4\uffe2\uff80\uff936 week drought, with well\uffe2\uff80\uff90defined rainfall events before and after the treatment. Ecosystem CO2 uptake rate (Aeco) declined 32% in response to the drought, with changes occurring within days and being reversible within weeks, even though the deeper soil layers did not become significantly drier and leaf\uffe2\uff80\uff90level water status of most large trees was not greatly affected. The reduced Aeco during the drought reflected both morphological and physiological responses. It is estimated that the drought\uffe2\uff80\uff90induced 32% reduction of Aeco has three principal components: (1) leaf fall increased two\uffe2\uff80\uff90fold whereas leaf expansion growth of some canopy dominants declined to 60%, leading to a 10% decrease in foliage coverage of the canopy. This might be the main reason for the persistent reduction of Aeco after rewatering. (2) The maximum photosynthetic electron transport rate at high light intensities in remaining leaves was reduced to 71% for three of the four species measured, even though no chronic photo\uffe2\uff80\uff90inhibition occurred. (3) Stomata closed, leading to a reduced ecosystem water conductance to water vapour (33% of pre\uffe2\uff80\uff90drought values), which not only reduced ecosystem carbon uptake rate, but may also have implications for water and energy budgets of tropical ecosystems. Additionally, individual rainforest trees responded differently, expressing different levels of stress and stress avoiding mechanisms. This functional diversity renders the individual response heterogeneous and has fundamental implications to scale leaf level responses to ecosystem dynamics.</p>", "keywords": ["580", "0301 basic medicine", "leaf area", "net ecosystem CO(2) exchange", "photosynthesis", "CLIMATE-CHANGE", "chlorophyll fluorescence", "CANOPY TREE", "drought", "15. Life on land", "6. Clean water", "FRENCH-GUIANA", "03 medical and health sciences", "leaf fall", "tropical trees KeyWords Plus: ATMOSPHERIC CO2 CONCENTRATIONS", "PHOTOSYSTEM-II", "XANTHOPHYLL CYCLE", "WATER-VAPOR", "L LEAVES", "13. Climate action", "leaf growth", "tropical rainforest", "photosynthetic electron transport", "GAS-EXCHANGE"]}, "links": [{"href": "https://doi.org/10.1111/j.1365-3040.2004.01231.x"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Plant%2C%20Cell%20%26amp%3B%20Environment", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1111/j.1365-3040.2004.01231.x", "name": "item", "description": "10.1111/j.1365-3040.2004.01231.x", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1111/j.1365-3040.2004.01231.x"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2004-10-01T00:00:00Z"}}], "links": [{"rel": "self", "type": "application/geo+json", "title": "This document as GeoJSON", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items?keywords=XANTHOPHYLL+CYCLE&f=json", "hreflang": "en-US"}, {"rel": "alternate", "type": "text/html", "title": "This document as HTML", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items?keywords=XANTHOPHYLL+CYCLE&f=html", "hreflang": "en-US"}, {"rel": "collection", "type": "application/json", "title": "Collection URL", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main", "hreflang": "en-US"}, {"type": "application/geo+json", "rel": "first", "title": "items (first)", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items?keywords=XANTHOPHYLL+CYCLE&", "hreflang": "en-US"}, {"rel": "last", "type": "application/geo+json", "title": "items (last)", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items?keywords=XANTHOPHYLL+CYCLE&offset=2", "hreflang": "en-US"}], "numberMatched": 2, "numberReturned": 2, "distributedFeatures": [], "timeStamp": "2026-09-20T18:06:34.824336Z"}