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Plants tightly control growth of their lateral organs, which led to the concept of apical dominance. However, outgrowth of the dormant lateral primordia is sensitive to the plant's nutritional status, resulting in an immense plasticity in plant architecture. While the impact of hormonal regulation on apical dominance is well characterized, the prime importance of sugar signaling to unleash lateral organ formation has just recently emerged. Here, we aimed to identify transcriptional regulators, which control the trade-off between growth of apical versus lateral organs. Making use of locally inducible gain-of-function as well as single and higher-order loss-of-function approaches of the sugar-responsive S1-basic-leucine-zipper (S1-bZIP) transcription factors, we disclosed their largely redundant function in establishing apical growth dominance. Consistently, comprehensive phenotypical and analytical studies of S1-bZIP mutants show a clear shift of sugar and organic nitrogen (N) allocation from apical to lateral organs, coinciding with strong lateral organ outgrowth. Tissue-specific transcriptomics reveal specific clade III SWEET sugar transporters, crucial for long-distance sugar transport to apical sinks and the glutaminase GLUTAMINE AMIDO-TRANSFERASE 1_2.1, involved in N homeostasis, as direct S1-bZIP targets, linking the architectural and metabolic mutant phenotypes to downstream gene regulation. Based on these results, we propose that S1-bZIPs control carbohydrate (C) partitioning from source leaves to apical organs and tune systemic N supply to restrict lateral organ formation by C/N depletion. Knowledge of the underlying mechanisms controlling plant C/N partitioning is of pivotal importance for breeding strategies to generate plants with desired architectural and nutritional characteristics.

Xanthoceras sorbifolium (yellowhorn) is a woody oil plant with super stress resistance and excellent oil characteristics. The yellowhorn oil can be used as biofuel and edible oil with high nutritional and medicinal value. However, genetic studies on yellowhorn are just in the beginning, and fundamental biological questions regarding its very long-chain fatty acid (VLCFA) biosynthesis pathway remain largely unknown. In this study, we reconstructed the VLCFA biosynthesis pathway and annotated 137 genes encoding relevant enzymes. We identified four oleosin genes that package triacylglycerols (TAGs) and are specifically expressed in fruits, likely playing key roles in yellowhorn oil production. Especially, by examining time-ordered gene co-expression network (TO-GCN) constructed from fruit and leaf developments, we identified key enzymatic genes and potential regulatory transcription factors involved in VLCFA synthesis. In fruits, we further inferred a hierarchical regulatory network with MYB-related (XS03G0296800) and B3 (XS02G0057600) transcription factors as top-tier regulators, providing clues into factors controlling carbon flux into fatty acids. Our results offer new insights into key genes and transcriptional regulators governing fatty acid production in yellowhorn, laying the foundation for efforts to optimize oil content and fatty acid composition. Moreover, the gene expression patterns and putative regulatory relationships identified here will inform metabolic engineering and molecular breeding approaches tailored to meet biofuel and bioproduct demands.

During the COVID pandemic of 2019, Sweden saw a huge increase in food prices, as many of the country's grocery chains import a large amount of all foods. This research is motivated by the Swedish Parliament's motion "Self-Sufficiency of Food in Sweden" and the need for innovative solutions to enhance Sweden's food supply. This study focuses on alternative urban agriculture methods, with a focus on aeroponics, aquaponics, hydroponics, and vertical farming, and their potential for self-sufficiency in Sweden. This study aims to fill the gap in Swedish research on soilless urban farming methods and contribute to the understanding and acceptance of the alternative methods above. The study seeks to determine whether the yield of alternative cultivation methods is comparable to traditional methods, soil-based and greenhouse-based farming, in terms of resources invested and to identify the alternative method with the highest yield. Resources in this thesis will be defined as the amount of water that is used. Our thesis aims to support businesses and local governance in decision-making regarding implementation of alternative urban farming in Sweden. A literature search was conducted using keywords such as hydroponic, vertical farming and sustainability. Statistical analysis of collected data indicates significant differences in yield and water usage among the collected examples which resulted in vertical hydroponic farming offering the highest yield in terms of space utilization, with significant statistical significance (p < 0.05). Additionally, hydroponic farming requires the least amount of water compared to other methods although this is not a certainty as there was no significant statistical difference between the different methods. The study demonstrates that hydroponic farming can achieve higher yields compared to traditional soil-based farming and other alternative farming methods. The study emphasizes organizational and governmental solutions to improve self-suff, Denna studie undersöker potentialen hos alternativa urbana odlingsmetoder för självförsörjning i Sverige. Den svenska riksdagen stödjer motion om "Självförsörjning av mat i Sverige" och behovet av innovativa lösningar för matförsörjning i landet. Denna forskning fyller en kunskapsbrist i den svenska litteraturen om jordlösa odlingssystem såsom aeroponiska, akvaponiska, hydroponiska och vertikala odlingar. Syftet med studien är att sammanfatta den befintliga kunskapen om dessa alternativa odlingsmetoder och klargöra deras fördelar i en urban miljö. Denna studie strävar att stödja företag och lokala myndigheter vid implementering av alternativa odlingsmetoder, genom att studera de alternativa odlingsmetodernas avkastning i förhållande till resursanvändning. Studien har samlat exempel från forskningsartiklar och företags-hemsidor som använde de ovan nämnda alternativa odlingsmetoder som sedan analyserats och jämfört deras avkastning med traditionella jordbaserade odlingar såsom åker odlingar och växthusbaserade odlingar. Med den statistisk analys som gjorts har vi funnit att vertikal hydroponisk odling visar den högsta avkastningen per yta jämfört med de andra alternativa odlingsmetoderna och traditionella odlingar. Vi har dessutom fastställt att hydroponiska odlingar använder minst vatten per kg skörd i jämförelse med andra metoder. Studien betonar vikten av att fokusera på organisatoriska och statliga lösningar för att öka självförsörjningsgraden på lokal och nationell nivå. Medan privatpersoner kan vara självförsörjande med grönsaker och frukt på en normalstor tomt, kan det vara svårt för alla privatpersoner att upprätthålla en egen grönsaksträdgård och undvika skador på marken och ekosystemtjänsterna i staden. Därmed riktar vi denna studie till kommunen och staten som ett stöd för att säkerställa självförsörjning på en lokal och regional nivå. För att uppnå hållbar samhällsutveckling och stödja självförsörjning av mat i Sverige, är integreringen av alternativa urba

The genetic control underlying natural variation in lignin content and composition in trees is not fully understood. We performed a systems genetic analysis to uncover the genetic regulation of lignin biosynthesis in a natural ‘SwAsp’ population of aspen (Populus tremula) trees. We analyzed gene expression by RNA sequencing (RNA-seq) in differentiating xylem tissues, and lignin content and composition using Pyrolysis-GC-MS in mature wood of 268 trees from 99 genotypes. Abundant variation was observed for lignin content and composition, and genome-wide association study identified proteins in the pentose phosphate pathway and arabinogalactan protein glycosylation among the top-ranked genes that are associated with these traits. Variation in gene expression and the associated genetic polymorphism was revealed through the identification of 312 705 local and 292 003 distant expression quantitative trait loci (eQTL). A co-expression network analysis suggested modularization of lignin biosynthesis and novel functions for the lignin-biosynthetic CINNAMYL ALCOHOL DEHYDROGENASE 2 and CAFFEOYL-CoA O-METHYLTRANSFERASE 3. PHENYLALANINE AMMONIA LYASE 3 was co-expressed with HOMEOBOX PROTEIN 5 (HB5), and the role of HB5 in stimulating lignification was demonstrated in transgenic trees. The systems genetic approach allowed linking natural variation in lignin biosynthesis to trees´ responses to external cues such as mechanical stimulus and nutrient availability.

Metacaspases are cysteine proteases present in plants, fungi and protists. While the association of metacaspases with cell death is studied in a range of organisms, their native substrates are largely unknown. Here, we explored the in vivo proteolytic landscape of the two metacaspases, CrMCA-I and CrMCA-II, present in the green freshwater alga Chlamydomonas reinhardtii, using mass spectrometry-based degradomics approach, during control conditions and salt stress. Comparison between the cleavage events of CrMCA-I and CrMCA-II in metacaspase mutants revealed unique cleavage preferences and substrate specificity. Degradome analysis demonstrated the relevance of the predicted metacaspase substrates to the physiology of C. reinhardtii cells and its adaptation during salt stress. Functional enrichment analysis indicated an involvement of CrMCA-I in the catabolism of carboxylic acids, while CrMCA-II plays an important role in photosynthesis and translation. Altogether, our findings suggest distinct cellular functions of the two metacaspases in C. reinhardtii during salt stress response.

With climate change, droughts are expected to be more frequent and severe, severely impacting plant biomass and quality. Here, we show that overexpressing the Arabidopsis gene AtFtsHi3 (FtsHi3OE) enhances drought-tolerant phenotypes without compromising plant growth. AtFtsHi3 encodes a chloroplast envelope pseudo-protease; knock-down mutants (ftshi3-1) are found to be drought tolerant but exhibit stunted growth. Altered AtFtsHi3 expression therefore leads to drought tolerance, while only diminished expression of this gene leads to growth retardation. To understand the underlying mechanisms of the enhanced drought tolerance, we compared the proteomes of ftshi3-1 and pFtsHi3-FtsHi3OE (pFtsHi3-OE) to wild-type plants under well-watered and drought conditions. Drought-related processes like osmotic stress, water transport, and abscisic acid response were enriched in pFtsHi3-OE and ftshi3-1 mutants following their enhanced drought response compared to wild-type. The knock-down mutant ftshi3-1 showed an increased abundance of HSP90, HSP93, and TIC110 proteins, hinting at a potential downstream role of AtFtsHi3 in chloroplast pre-protein import. Mathematical modeling was performed to understand how variation in the transcript abundance of AtFtsHi3 can, on the one hand, lead to drought tolerance in both overexpression and knock-down lines, yet, on the other hand, affect plant growth so differently. The results led us to hypothesize that AtFtsHi3 may form complexes with at least two other protease subunits, either as homo- or heteromeric structures. Enriched amounts of AtFtsH7/9, AtFtsH11, AtFtsH12, and AtFtsHi4 in ftshi3-1 suggest a possible compensation mechanism for these proteases in the hexamer.

With the growing demand for an increase in food production, whilst 30% of thecrop production is lost due to plant diseases, there is a need for plant diseasedetection that do not require laboratories and trained personnel. This can besolved by the usage of nanotechnology and the integration of microneedles.Microneedles can extract biofluids from the plants, and with the integrationwith a sensor, allow for on-site disease detection.The most recently developed type of microneedle is the porous microneedle,which extract biofluids by capillary action. Previous papers have proposeddifferent materials and processes for the fabrication of porous microneedlesbut state that further research has to be done. This Thesis aims to createprotocols for fabrication of porous microneedles from different cellulosicmaterials as well as evaluate their characteristics.Before the protocols were established, two master molds were created forthe casting of the porous microneedles. One by engraving a PMMA sheetusing a CO2 laser, and the other by 3D printing a resin mold. The twomaterials that were used were cellulose acetate and chromatography paper.The materials were used both separately and combined in the fabricationprocess. To characterize the porous microneedles, three properties wereevaluated, porosity, mechanical stability and extraction capability.The results from the fabrication of porous microneedles and the propertytests has provided information for further development of the project as wellas future work regarding porous microneedles., På grund av den ökande efterfrågan på matproduktionen i världen ikombination med det faktum att ca 30% av all den mat som odlas går förloradpå grund av plantsjukdomar, medför att det finns ett behov av detektering avdessa sjukdomar på ett snabbt och smidigt sätt som inte kräver laboratoriereller utbildad personal. Det här kan lösas genom användadet av nanoteknologioch integrering av mikronålar. Mikronålar kan extrahera biovätskor frånplantor, och genom att integrera mikronålarna med sensorer, tillåta detekteringpå plats på odlingsmarkerna.En typ av mikronål är den porösa mikronålen som genom kapillärkraftkan extrahera biovätskor. Tidigare artiklar har presenterat olika material ochprocesser för tillverkningen av porösa mikronålar, men mer forskning krävsför att utveckla porösa mikronålar för extrahering av biovätskor från plantor.Syftet med den här avhandlingen är skapa protokoll för tillverkningen avporösa mikronålar från cellulosamaterial, samt utvärdera dess egenskaper.Innan protokollen etablerades skapades två master formar för tillverkningenav de porösa mikronålarna. En form skapades genom ingraveringi PMMA med hjälp av en CO2 laser och den andra genom att med hjälpav en 3D printer skriva ut en form med resin. De två materialen somanvändes för tillverkningen av de porösa mikronålarna var cellulosa acetat ochkromatografipapper. Materialen användes både var för sig och tillsammans.För att karaktärisera de porösa mikronålarna utvärderades tre egenskaper,porositet, mekanisk stabilitet och extraktionsförmåga.Resultaten från tillverkningen av porösa mikronålar och de karaktäriseradeegenskaperna har bidragit med information för fortsatt utveckling av projektetsamt framtida arbete med porösa mikronålar.

Wheat (Triticum aestivum) is one of the most important crops grown globally together with maize and rice. Many crop species, wheat included, contain undesired traits or traits that could be better adapted to the changing environment. Biotechnological modifications to alter such traits in wheat are much less studied than in many other crops and there are several obstacles to overcome such as lack of efficient standard protocols for the transformation step. One part of the problem is the large size of its genome which makes gene integration more difficult. One problematic trait is that wheat can take up and store large amounts of cadmium which is a toxic heavy metal that should not be consumed in large quantities. Cadmium is transported into the root cells through different transporters such as NRAMP6. The cadmium accumulates in the grains which are consumed by humans and animals and can cause health problems. Development of biotechnological methods for wheat transformation is therefore desired. With such methods, the undesired cadmium uptake and storage in wheat could potentially be decreased. The aim of this MSc project was to develop an improved transformation method to faciliate gene editing in wheat, and the target was the NRAMP6 transporter. Additionally, a new plasmid for this purpose was designed and successfully cloned in silico using SnapGene. Two new transformation methods were tested in this project: floral dipping in an Agrobacterium solution and Agrobacterium pipetting. They both utilize Agrobacterium tumefaciens' natural ability to transfer part of its DNA into the genome of a plant cell. A plasmid with a transfer-DNA (T-DNA) containing a CRISPR/Cas9 construct targeting the NRAMP6 transporter was transformed into A. tumefaciens. The Agrobacterium was thereafter added to an infiltration solution which was used to treat pre-anthesis wheat spikes with either floral dipping or Agrobacterium pipetting with the purpose of transferring the T-DNA into them. Bo

Formation of the apical hook in etiolated dicot seedlings results from differential growth in the hypocotyl apex and is tightly controlled by environmental cues and hormones, among which auxin and gibberellins (GAs) play an important role. Cell expansion is tightly regulated by the cell wall, but whether and how feedback from this structure contributes to hook development are still unclear. Here, we show that etiolated seedlings of the Arabidopsis (Arabidopsis thaliana) quasimodo2-1 (qua2) mutant, defective in pectin biosynthesis, display severe defects in apical hook formation and maintenance, accompanied by loss of asymmetric auxin maxima and differential cell expansion. Moreover, qua2 seedlings show reduced expression of HOOKLESS1 (HLS1) and PHYTOCHROME INTERACTING FACTOR4 (PIF4), which are positive regulators of hook formation. Treatment of wild-type seedlings with the cellulose inhibitor isoxaben (isx) also prevents hook development and represses HLS1 and PIF4 expression. Exogenous GAs, loss of DELLA proteins, or HLS1 overexpression partially restore hook development in qua2 and isx-treated seedlings. Interestingly, increased agar concentration in the medium restores, both in qua2 and isx-treated seedlings, hook formation, asymmetric auxin maxima, and PIF4 and HLS1 expression. Analyses of plants expressing a F & ouml;rster resonance energy transfer-based GA sensor indicate that isx reduces accumulation of GAs in the apical hook region in a turgor-dependent manner. Lack of the cell wall integrity sensor THESEUS 1, which modulates turgor loss point, restores hook formation in qua2 and isx-treated seedlings. We propose that turgor-dependent signals link changes in cell wall integrity to the PIF4-HLS1 signaling module to control differential cell elongation during hook formation. Loss of cell wall integrity suppresses gibberellic acid accumulation and HOOKLESS1 and PHYTOCHROME INTERACTING FACTOR4 expression, ultimately repressing apical hook formation in Arabid

Plant-based expression systems have emerged as promising avenues for the production of recombinant N-linked glycoproteins. This review offers insights into the evolution and progress of plant glycoengineering. It delves into the distinctive features of plant-derived N-glycans, the diverse range of plant hosts employed for glycoprotein synthesis, and the advancements in glycoengineering strategies aimed at generating glycoproteins with N-glycan structures akin to those produced in mammalian cell lines. Furthermore, alternative strategies for augmenting glycoengineering efforts and the current spectrum of applications for plant-produced N-glycan recombinant proteins are examined, underscoring their potential significance in biopharmaceutical manufacturing., QC 20240626

The present study conducted metabolomics profiling (targeted and untargeted) in the roots of two wheat varieties (BARANI-70 and NARC-09) under arsenate stress in a hydroponic experiment. The findings indicated a better growth response of BARANI-70 compared to the NARC-09. From amino acid profiling, a total of 26 amino acids (AAs) were quantified in roots. BARANI-70 showed higher induction of stress-responsive AAs compared to the NARC-09. From untargeted metabolomics, a total of 136 metabolites were identified: AAs, fatty acids, purines, carnitines, LysoPCs, and others. The KEGG pathway identified pathways such as linoleic acid metabolism, TCA cycle, glutathione metabolism, and aminoacyl-tRNA biosynthesis that were regulated to improve the defense of tolerant variety. BARANI-70 emerged as a tolerant variety based on the psychological response, As accumulation, and behavior of stress-responsive metabolites. This study should facilitate the breeding of low-As accumulating wheat varieties for future application to ensure sustainable production and food safety.

Plant biomass plays an increasingly important role in the circular bioeconomy, replacing non-renewable fossil resources. Genetic engineering of this lignocellulosic biomass could benefit biorefinery transformation chains by lowering economic and technological barriers to industrial processing. However, previous efforts have mostly targeted the major constituents of woody biomass: cellulose, hemicellulose and lignin. Here we report the engineering of wood structure through the introduction of callose, a polysaccharide novel to most secondary cell walls. Our multiscale analysis of genetically engineered poplar trees shows that callose deposition modulates cell wall porosity, water and lignin contents and increases the lignin–cellulose distance, ultimately resulting in substantially decreased biomass recalcitrance. We provide a model of the wood cell wall nano-architecture engineered to accommodate the hydrated callose inclusions. Ectopic polymer introduction into biomass manifests in new physico-chemical properties and offers new avenues when considering lignocellulose engineering., QC 20231115

There is considerable evidence for local adaptation in nature, yet important questions remain regarding its genetic basis. How many loci are involved? What are their effect sizes? What is the relative importance of conditional neutrality versus genetic trade-offs? Here we address these questions in the self-pollinating, annual plant Arabidopsis thaliana. We used 400 recombinant inbred lines (RILs) derived from two locally adapted populations in Italy and Sweden, grew the RILs and parents at the parental locations, and mapped quantitative trait loci (QTL) for mean fitness (fruits/seedling planted). We previously published results from the first 3 years of the study, and here add five additional years, providing a unique opportunity to assess how temporal variation in selection might affect QTL detection and classification. We found 10 adaptive and one maladaptive QTL in Italy, and six adaptive and four maladaptive QTL in Sweden. The discovery of maladaptive QTL at both sites suggests that even locally adapted populations are not always at their genotypic optimum. Mean effect sizes for adaptive QTL, 0.97 and 0.55 fruits in Italy and Sweden, respectively, were large relative to the mean fitness of the RILs (approximately 8 fruits/seedling planted at both sites). Both genetic trade-offs (four cases) and conditional neutrality (seven cases) contribute to local adaptation in this system. The 8-year dataset provided greater power to detect QTL and to estimate their locations compared to our previous 3-year study, identifying one new genetic trade-off and resolving one genetic trade-off into two conditionally adaptive QTL.

Trees constitute promising renewable feedstocks for biorefinery using biochemical conversion, but their recalcitrance restricts their attractiveness for the industry. To obtain trees with reduced recalcitrance, large-scale genetic engineering experiments were performed in hybrid aspen blindly targeting genes expressed during wood formation and 32 lines representing seven constructs were selected for characterization in the field. Here we report phenotypes of five-year old trees considering 49 traits related to growth and wood properties. The best performing construct considering growth and glucose yield in saccharification with acid pretreatment had suppressed expression of the gene encoding an uncharacterized 2-oxoglutarate-dependent dioxygenase (2OGD). It showed minor changes in wood chemistry but increased nanoporosity and glucose conversion. Suppressed levels of SUCROSE SYNTHASE, (SuSy), CINNAMATE 4-HYDROXYLASE (C4H) and increased levels of GTPase activating protein for ADP-ribosylation factor ZAC led to significant growth reductions and anatomical abnormalities. However, C4H and SuSy constructs greatly improved glucose yields in saccharification without and with pretreatment, respectively. Traits associated with high glucose yields were different for saccharification with and without pretreatment. While carbohydrates, phenolics and tension wood contents positively impacted the yields without pretreatment and growth, lignin content and S/G ratio were negative factors, the yields with pretreatment positively correlated with S lignin and negatively with carbohydrate contents. The genotypes with high glucose yields had increased nanoporosity and mGlcA/Xyl ratio, and some had shorter polymers extractable with subcritical water compared to wild-type. The pilot-scale industrial-like pretreatment of best-performing 2OGD construct confirmed its superior sugar yields, supporting our strategy.

Plants are composed of complex organisms that include morphological, physiological and biochemical segments. A number of environmental factors such as, heavy metals, drought, salinity, heat, and cold cause stress towards plants and impact on their growth and yield values. Heavy metal contamination and drought are considered to be two significant environmental (abiotic) factors that are receiving increased attention due their effects on plants. Many plant species from previously non-drought prone areas now face drought as a new stress factor and must develop their avoidance mechanisms. Comparing drought-related tolerance strategies, plants have developed a number of strategies to fight against heavy metal pollution due to its wide coverage. These heavy metal tolerance strategies include detoxification, compartmentalization, and storage in cell vacuoles in plants. Few similarities have been found in the mechanisms of both drought and heavy metal strategies. The use of beneficial microbes is considered as one of the most promising methods to improve stress tolerance because plant-associated microbes decrease metal accumulation while enhancing nutrient supply and water under such stress. In this review, we summarize how drought and heavy metals contamination effect on plant growth, with particular focus on stress avoidance and tolerance mechanisms, as well as, the role of microbes to enhance stress tolerance. Recommendations including irrigation, fertilization and molecular techniques to increase the plant’s tolerance mechanisms against heavy metal and drought conditions are also discussed.

Xylan that comprises roughly 25% of hardwood biomass is undesirable in biorefinery applications involving saccharification and fermentation. Efforts to reduce xylan levels have therefore been made in many species, usually resulting in improved saccharification. However, such modified plants have not yet been tested under field conditions. Here we evaluate the field performance of transgenic hybrid aspen lines with reduced xylan levels and assess their usefulness as short-rotation feedstocks for biorefineries. Three types of transgenic lines were tested in four-year field tests with RNAi constructs targeting either Populus GT43 clades B and C (GT43BC) corresponding to Arabidopsis clades IRX9 and IRX14, respectively, involved in xylan backbone biosynthesis, GATL1.1 corresponding to AtGALT1 involved in xylan reducing end sequence biosynthesis, or ASPR1 encoding an atypical aspartate protease. Their productivity, wood quality traits, and saccharification efficiency were analyzed. The only lines differing significantly from the wild type with respect to growth and biotic stress resistance were the ASPR1 lines, whose stems were roughly 10% shorter and narrower and leaves showed increased arthropod damage. GT43BC lines exhibited no growth advantage in the field despite their superior growth in greenhouse experiments. Wood from the ASPR1 and GT43BC lines had slightly reduced density due to thinner cell walls and, in the case of ASPR1, larger cell diameters. The xylan was less extractable by alkali but more hydrolysable by acid, had increased glucuronosylation, and its content was reduced in all three types of transgenic lines. The hemicellulose size distribution in the GALT1.1 and ASPR1 lines was skewed towards higher molecular mass compared to the wild type. These results provide experimental evidence that GATL1.1 functions in xylan biosynthesis and suggest that ASPR1 may regulate this process. In saccharification without pretreatment, lines of all three constructs provide

Metacaspases are part of an evolutionarily broad family of multifunctional cysteine proteases, involved in disease and normal development. As the structure-function relationship of metacaspases remains poorly understood, we solved the X-ray crystal structure of an Arabidopsis thaliana type II metacaspase (AtMCA-IIf) belonging to a particular subgroup not requiring calcium ions for activation. To study metacaspase activity in plants, we developed an in vitro chemical screen to identify small molecule metacaspase inhibitors and found several hits with a minimal thioxodihydropyrimidine-dione structure, of which some are specific AtMCA-IIf inhibitors. We provide mechanistic insight into the basis of inhibition by the TDP-containing compounds through molecular docking onto the AtMCA-IIf crystal structure. Finally, a TDP-containing compound (TDP6) effectively hampered lateral root emergence in vivo, probably through inhibition of metacaspases specifically expressed in the endodermal cells overlying developing lateral root primordia. In the future, the small compound inhibitors and crystal structure of AtMCA-IIf can be used to study metacaspases in other species, such as important human pathogens, including those causing neglected diseases.

European canker, caused by the necrotrophic fungus Neonectria ditissima, is the most serious disease in apple production in Sweden. The disease is favored by a relatively cool and rainy climate. The canker damages have a significant economic impact due to reduced bearing surface and increased orchard management costs. The possibilities for chemical and biological control are very limited. Therefore, directed breeding for new resistant cultivars is urgently needed. Knowledge of inheritance of canker resistance and understanding of molecular mechanisms involved in resistant and susceptible responses to fungal attacks would facilitate breeding. In this study, we evaluated the tempo-spatial differences in plant-pathogen interactions in a set of partially resistant and susceptible cultivars by conducting metabolomic and lipidomic analyses. The major trends in metabolomics and lipidomic profiles were common among cultivars, irrespective of the degree of susceptibility. Several metabolites and lipids varied with time point and cultivar under N. ditissima infection. Putative key metabolites such as suberic acid and jasmonic acid were upregulated in all cultivars upon infection. Additionally, several lipids exhibited changes 30 to 45 days post-inoculation. Thus, the approach used seems to have resulted in a rich data set to be further analyzed in light of ongoing QTL-mapping efforts.

Urtica dioica is a perennial herb from the family of Urticaceae that is commonly known as stinging nettle. This plant is widespread in Europe, Africa, America, and a part of Asia, as it adapts to different environments and climatic conditions. The leaves, stalk, and bark of U. dioica found applications in the field of nutrition, cosmetics, textile, pest control and pharmacology. In this connection, bioactive chemical constituents such as flavonoids, phenolic acids, amino acids, carotenoids, and fatty acids have been isolated from the plant. With this review, we aim at providing an updated and comprehensive overview of the contributions in literature reporting computational, in vitro, pre-clinical and clinical data supporting the therapeutic applications of U. dioica. Experimental evidence shows that U. dioica constituents and extracts can provide neuroprotective effects by acting through a combination of different molecular mechanisms, that are discussed in the review. These findings could lay the basis for the identification and design of more effective tools against neurodegenerative diseases.

Xanthoceras sorbifolium (yellowhorn) is a woody oil plant with super stress resistance and excellent oil characteristics. The yellowhorn oil can be used as biofuel and edible oil with high nutritional and medicinal value. However, genetic studies on yellowhorn are just in the beginning, and fundamental biological questions regarding its very long-chain fatty acid (VLCFA) biosynthesis pathway remain largely unknown. In this study, we reconstructed the VLCFA biosynthesis pathway and annotated 137 genes encoding relevant enzymes. We identified four oleosin genes that package triacylglycerols (TAGs) and are specifically expressed in fruits, likely playing key roles in yellowhorn oil production. Especially, by examining time-ordered gene co-expression network (TO-GCN) constructed from fruit and leaf developments, we identified key enzymatic genes and potential regulatory transcription factors involved in VLCFA synthesis. In fruits, we further inferred a hierarchical regulatory network with MYB-related (XS03G0296800) and B3 (XS02G0057600) transcription factors as top-tier regulators, providing clues into factors controlling carbon flux into fatty acids. Our results offer new insights into key genes and transcriptional regulators governing fatty acid production in yellowhorn, laying the foundation for efforts to optimize oil content and fatty acid composition. Moreover, the gene expression patterns and putative regulatory relationships identified here will inform metabolic engineering and molecular breeding approaches tailored to meet biofuel and bioproduct demands.

Prata med plantor – går det? 6 juli 2023Artikel från forskning.seÄmne: Miljö & klimat, Natur & teknik - ABIGAIL SYKES I naturen pågår ständiga samtal – som människor inte lärt sig uppfatta. Men det går att kommunicera med växter och vi gör det också hela tiden, säger forskare. De senaste åren har forskning visat att tomatplantor ”skriker” när de klipps av, att växter lär sig att en del beröring inte är farlig samt att de varnar varandra för hot. Är växter smartare än vi trodde, och vad betyder det i så fall för hur vi behandlar dem? Växter, träd och andra organismer kommunicerar med varandra genom ljud, ljus, beröring samt framför allt kemiska signaler som dofter både ovan och under jord. Genom sammankopplade nätverk av rötter och svamptrådar sänder exempelvis starkare träd näring till svagare träd . Nyligen kom en studie från universitetet i Tel Aviv som visade att tomat- och tobaksplantor avger högfrekventa ljud när de utsätts för torka eller klipps av – ljud som forskarna först spelade in med ultraljudsmikrofoner och sedan upp i ett långsammare tempo så att människor kunde höra dem som ett klickande., Detta är en populärvetenskaplig text om bland annat min forskning, där jag är intervjuad och har varit medförfattare. Men det är vetenskapsjournalist Abigail Sykes som är författare., The Posthumanities Hub

UV-A- or UV-B-enriched growth light were given to basil plants at non-stress-inducing intensities. UV-A-enriched growth light gave rise to a sharp rise in expression of PAL and CHS genes in leaves, an effect that rapidly declined after 1-2 days of exposure. On the other hand, leaves of plants grown in UV-B-enriched light had a more stable and long-lasting increase in expression of these genes and also showed a stronger increase in leaf epidermal flavonol content. UV supplementation of growth light also led to shorter more compact plants with a stronger UV effect the younger the tissue. The effect was more prominent in plants grown under UV-B-enriched light than in those grown under UV-A. Parameters particularly affected were internode lengths, petiole lengths and stem stiffness. In fact, the bending angle of the 2nd internode was found to increase as much as 67% and 162% for plants grown in the UV-A- and UV-B-enriched treatments, respectively. The decreased stem stiffness was probably caused by both an observed smaller internode diameter and a lower specific stem weight, as well as a possible decline in lignin biosynthesis due to competition for precursor by the increased flavonoid biosynthesis. Overall, at the intensities used, UV-B wavelengths are stronger regulators of morphology, gene expression and flavonoid biosynthesis than UV-A wavelengths., UV4quality

Hydrogen peroxide (H2O2) is an important molecule that regulates antioxidant responses that are crucial for plant stress resistance. Exposure to low levels of ultraviolet-B radiation (UV-B, 280–315 nm) can also activate antioxidant defenses and acclimation responses. However, how H2O2 and UV-B interact to promote stress acclimation remains poorly understood. In this work, a transgenic model of Nicotiana tabacum cv Xanthi nc, with elevated Mn-superoxide dismutase (Mn-SOD)activity, was used to study the interaction between the constitutive overproduction of H2O2 and a 14-day UV-B treatment (1.75 kJ m−2 d−1 biologically effective UV-B). Subsequently, these plants were subjected to a 7-day moderate drought treatment to evaluate the impact on drought resistance of H2O2- and UV-dependent stimulation of the plants' antioxidant system. The UV-B treatment enhanced H2O2 levels and altered the antioxidant status by increasing the epidermal flavonol index, Trolox Equivalent Antioxidant Capacity, and catalase, peroxidase and phenylalanine ammonia lyase activities in the leaves. UV-B also retarded growth and suppressed acclimation responses in highly H2O2-overproducing transgenic plants. Plants not exposed to UV-B had a higher drought resistance in the form of higher relative water content of leaves. Our data associate the interaction between Mn-SOD transgene overexpression and the UV-B treatment with a stress response. Finally, we propose a hormetic biphasic drought resistance response curve as a function of leaf H2O2 content in N. tabacum cv Xanthi., UV4quality

Active hydroponic substrates that stimulate on demand the plant growth have not been demonstrated so far. Here, we developed the eSoil, a low -power bioelectronic growth scaffold that can provide electrical stimulation to the plants' root system and growth environment in hydroponics settings. eSoil's active material is an organic mixed ionic electronic conductor while its main structural component is cellulose, the most abundant biopolymer. We demonstrate that barley seedlings that are widely used for fodder grow within the eSoil with the root system integrated within its porous matrix. Simply by polarizing the eSoil, seedling growth is accelerated resulting in increase of dry weight on average by 50% after 15 d of growth. The effect is evident both on root and shoot development and occurs during the growth period after the stimulation. The stimulated plants reduce and assimilate NO3- more efficiently than controls, a finding that may have implications on minimizing fertilizer use. However, more studies are required to provide a mechanistic understanding of the physical and biological processes involved. eSoil opens the pathway for the development of active hydroponic scaffolds that may increase crop yield in a sustainable manner., Funding Agencies|University

Reproductive phase change is well characterized in angiosperm model species, but less studied in gymnosperms. We utilize the early cone-setting acrocona mutant to study reproductive phase change in the conifer Picea abies (Norway spruce), a gymnosperm. The acrocona mutant frequently initiates cone-like structures, called transition shoots, in positions where wild-type P. abies always produces vegetative shoots. We collect acrocona and wild-type samples, and RNA-sequence their messenger RNA (mRNA) and microRNA (miRNA) fractions. We establish gene expression patterns and then use allele-specific transcript assembly to identify mutations in acrocona. We genotype a segregating population of inbred acrocona trees. A member of the SQUAMOSA BINDING PROTEIN-LIKE (SPL) gene family, PaSPL1, is active in reproductive meristems, whereas two putative negative regulators of PaSPL1, miRNA156 and the conifer specific miRNA529, are upregulated in vegetative and transition shoot meristems. We identify a mutation in a putative miRNA156/529 binding site of the acrocona PaSPL1 allele and show that the mutation renders the acrocona allele tolerant to these miRNAs. We show co-segregation between the early cone-setting phenotype and trees homozygous for the acrocona mutation. In conclusion, we demonstrate evolutionary conservation of the age-dependent flowering pathway and involvement of this pathway in regulating reproductive phase change in the conifer P. abies.

The correct development of seeds is a pivotal requirement for species preservation. This process depends on the balance between sensing the environmental stimuli/stressors and hormone-mediated transduction, which results in physiological responses. The red and blue regions of the electromagnetic spectrum are known to influence seed dormancy and germination. Here, we report on the effects induced by the blue (peak at 430 nm) and red (peak at 650 nm) regions of the electromagnetic spectrum on seeds from photo- and skotomorphogenetic capsules developed under white, blue, or red light. Regardless of exposure, seeds from skotomorphogenetic capsules showed an almost absent dormancy in association with altered germination kinetics. Conversely, in seeds from photomorphogenetic capsules, the exposure to the blue region induced skotomorphogenetic-like effects, while the exposure to the whole visible range (350–750 nm), as well as to only the red region, showed a dose-related trend. The observed differences appeared to be dependent on the wavelengths in the red and to be based on transduction mechanisms taking place in fruits. While the molecular bases of this differential effect need to be clarified, the results hint at the role played by different light wavelengths and intensities in seed development and germination. These findings may be relevant for applications in crop production and species safeguarding.

Plants are able to sense and respond to a myriad of external stimuli, using different signal transduction pathways, including electrical signaling. The ability to monitor plant responses is essential not only for fundamental plant science, but also to gain knowledge on how to interface plants with technology. Still, the field of plant electrophysiology remains rather unexplored when compared to its animal counterpart. Indeed, most studies continue to rely on invasive techniques or on bulky inorganic electrodes that oftentimes are not ideal for stable integration with plant tissues. On the other hand, few studies have proposed novel approaches to monitor plant signals, based on non-invasive conformable electrodes or even organic transistors. Organic electrochemical transistors (OECTs) are particularly promising for electrophysiology as they are inherently amplification devices, they operate at low voltages, can be miniaturized, and be fabricated in flexible and conformable substrates. Thus, in this study, we characterize OECTs as viable tools to measure plant electrical signals, comparing them to the performance of the current standard, Ag/AgCl electrodes. For that, we focused on two widely studied plant signals: the Venus flytrap (VFT) action potentials elicited by mechanical stimulation of its sensitive trigger hairs, and the wound response of Arabidopsis thaliana. We found that OECTs are able to record these signals without distortion and with the same resolution as Ag/AgCl electrodes and that they offer a major advantage in terms of signal noise, which allow them to be used in field conditions. This work establishes these organic bioelectronic devices as non-invasive tools to monitor plant signaling that can provide insight into plant processes in their natural environment.

State-of-the-art technology based on organic electronics can be used as a flow-free delivery method for organic substances with high spatial resolution. Such highly targeted drug micro applications can be used in plant research for the regulation of physiological processes on tissue and cellular levels. Here, for the first time, an organic electronic ion pump (OEIP) is reported that can transport an isoprenoid-type cytokinin, N-6-isopentenyladenine (iP), to intact plants. Cytokinins (CKs) are plant hormones involved in many essential physiological processes, including primary root (PR) and lateral root (LR) development. Using the Arabidopsis thaliana root as a model system, efficient iP delivery is demonstrated with a biological output - cytokinin-related PR and LR growth inhibition. The spatial resolution of iP delivery, defined for the first time for an organic compound, is shown to be less than 1 mm, exclusively affecting the OEIP-targeted LR. Results from the application of the high-resolution OIEP treatment method confirm previously published findings showing that the influence of CKs may vary at different stages of LR development. Thus, OEIP-based technologies offer a novel, electronically controlled method for phytohormone delivery that could contribute to unraveling cytokinin functions during different developmental processes with high specificity., Funding Agencies|Knut and Alice Wallenberg (KAW) Foundation ShapeSystems project [KAW 2012.0050]; Ministry of Education, Youth and Sports of the Czech Republic [CZ.02.2.69/0.0/0.0/16_027/0008482]; Kempe Foundation [JCK-1910]; ERDF project by the Ministry of Education, Youth and Sports of the Czech Republic [CZ.02.1.01/0.0/0.0/16_019/0000827, CZ.02.1.01/0.0/0.0/16_019/0000738]; Czech Science Foundation [19-00973S]; VR (Vetenskapsradet); Vinnova; KAW

Leaf senescence can be induced by stress or aging, sometimes in a synergistic manner. It is generally acknowledged that the ability to withstand senescence-inducing conditions can provide plants with stress resilience. Although the signaling and transcriptional networks responsible for a delayed senescence phenotype, often referred to as a functional stay-green trait, have been actively investigated, very little is known about the subsequent metabolic adjustments conferring this aptitude to survival. First, using the individually darkened leaf (IDL) experimental setup, we compared IDLs of wild-type (WT) Arabidopsis (Arabidopsis thaliana) to several stay-green contexts, that is IDLs of two functional stay-green mutant lines, oresara1-2 (ore1-2) and an allele of phytochrome-interacting factor 5 (pif5), as well as to leaves from a WT plant entirely darkened (DP). We provide compelling evidence that arginine and ornithine, which accumulate in all stay-green contexts—likely due to the lack of induction of amino acids (AAs) transport—can delay the progression of senescence by fueling the Krebs cycle or the production of polyamines (PAs). Secondly, we show that the conversion of putrescine to spermidine (SPD) is controlled in an age-dependent manner. Thirdly, we demonstrate that SPD represses senescence via interference with ethylene signaling by stabilizing the ETHYLENE BINDING FACTOR1 and 2 (EBF1/2) complex. Taken together, our results identify arginine and ornithine as central metabolites influencing the stress- and age-dependent progression of leaf senescence. We propose that the regulatory loop between the pace of the AA export and the progression of leaf senescence provides the plant with a mechanism to fine-tune the induction of cell death in leaves, which, if triggered unnecessarily, can impede nutrient remobilization and thus plant growth and survival.

Metacaspases are essential cysteine proteases present in plants, fungi, and protists that are regulated by calcium binding and proteolytic maturation through mechanisms not yet understood. Here, we developed and validated activity-based probes for the three main metacaspase types, and used them to study calcium-mediated activation of metacaspases from their precursors in vitro. By combining substrate-inspired tetrapeptide probes containing an acyloxymethylketone (AOMK) reactive group, with purified representatives of type-I, type-II, and type-III metacaspases, we were able to demonstrate that labeling of mature metacaspases is strictly dependent on calcium. The probe with the highest affinity for all metacaspases also labels higher molecular weight proteoforms of all three metacaspases only in the presence of calcium, displaying the active, unprocessed metacaspase intermediates. Our data suggest that metacaspase activation proceeds through previously unknown active intermediates that are formed upon calcium binding, before precursor processing.

With the need to increase plant productivity, one of the challenges plant scientists are facing is to identify genes that play a role in beneficial plant traits. Moreover, even when such genes are found, it is generally not trivial to transfer this knowledge about gene function across species to identify functional orthologs. Here, we focused on the leaf to study plant growth. First, we built leaf growth transcriptional networks in Arabidopsis (Arabidopsis thaliana), maize (Zea mays), and aspen (Populus tremula). Next, known growth regulators, here defined as genes that when mutated or ectopically expressed alter plant growth, together with cross-species conserved networks, were used as guides to predict novel Arabidopsis growth regulators. Using an in-depth literature screening, 34 out of 100 top predicted growth regulators were confirmed to affect leaf phenotype when mutated or overexpressed and thus represent novel potential growth regulators. Globally, these growth regulators were involved in cell cycle, plant defense responses, gibberellin, auxin, and brassinosteroid signaling. Phenotypic characterization of loss-of-function lines confirmed two predicted growth regulators to be involved in leaf growth (NPF6.4 and LATE MERISTEM IDENTITY2). In conclusion, the presented network approach offers an integrative cross-species strategy to identify genes involved in plant growth and development.

Non-symbiotic globin class #1 (Glb1) genes are expressed in different plant organs, have a high affinity for oxygen, and are related to nitric oxide (NO) turnover. Previous studies showed that soybean Glb1 genes are upregulated in soybean plants under flooding conditions. Herein, the GmGlb1-1 gene was identified in soybean as being upregulated in the nematode-resistant genotype PI595099 compared to the nematode-susceptible cultivar BRS133 during plant parasitism by Meloidogyne incognita. The Arabidopsis thaliana and Nicotiana tabacum transgenic lines overexpressing the GmGlb1-1 gene showed reduced susceptibility to M. incognita. Consistently, gall morphology data indicated that pJ2 nematodes that infected the transgenic lines showed developmental alterations and delayed parasitism progress. Although no significant changes in biomass and seed yield were detected, the transgenic lines showed an elongated, etiolation-like growth under well-irrigation, and also developed more axillary roots under flooding conditions. In addition, transgenic lines showed upregulation of some important genes involved in plant defense response to oxidative stress. In agreement, higher hydrogen peroxide accumulation and reduced activity of reactive oxygen species (ROS) detoxification enzymes were also observed in these transgenic lines. Thus, based on our data and previous studies, it was hypothesized that constitutive overexpression of the GmGlb1-1 gene can interfere in the dynamics of ROS production and NO scavenging, enhancing the acquired systemic acclimation to biotic and abiotic stresses, and improving the cellular homeostasis. Therefore, these collective data suggest that ectopic or nematode-induced overexpression, or enhanced expression of the GmGlb1-1 gene using CRISPR/dCas9 offers great potential for application in commercial soybean cultivars aiming to reduce plant susceptibility to M. incognita., Funding Agencies|CAPES [88887.642997/2021-00]; FAPESP [2019/13936-0]; CAPES/Cofecub project; CNPq; FAP-DF; INCT Plant Stress Biotech; EMBRAPA; INCT Bioethanol

QC 20230614

Vanadium (V) has been considered a potentially toxic element and has not gotten adequate attention compared to similar kinds of heavy metals in the soil. It acts as an essential element for its various uses in the industrial sectors, especially steel and chemical production. Due to natural and anthropogenic factors such as rock weathering, metal ore mining, fossil fuel combustion and agrochemical usage, the soil environment has become contaminated with V. Vanadium contamination has caused a great threat to the plants and animals well as to the humans. To minimize the hazard potential from V, several remediation methods have been investigated and practiced worldwide. This chapter includes the remediation techniques for V-contaminated soils by physical, chemical and biological approaches that can be identified in this regard. Chemical and physical treatments have a relatively faster process; however, they have drawbacks due to their expensiveness and durability. Compared to physico-chemical techniques, phytoremediation is an environmentally friendly economic management option, and so are the soil amendments. However, the phytoremediation process is a slow process, and the remediation success greatly depends on the plant species used in the management. Integrated techniques with microorganisms could enhance the efficiency and pace of phytoremediation management.

Rubber plantations are known to udergo various biotic and abiotic stresses. However, the symbiotic bacterial endophytes that inhabit them provide protection. Here, we isolated bacterial endophytes from the rubber tree, Hevea brasiliensis (Willd. ex A.Juss.) Müll.Arg. and studied their antagonistic activity against major pathogens such as Phytophthora meadii, Corynespora cassiicola and Corticium salmonicolar. The antifungal metabolites such as HCN, siderophores and salicylic acid were produced by the antagonistic endophytes under in vitro conditions. Bioassay showed the growth promotion by a consortium of selected antagonistic endophytes in H. brasiliensis seedlings. The photosynthetic efficiency of seedlings increased after endophyte inoculation. Endophyte-treated plants showed accumulation of starch granules in root tissues. The selected antagonistic isolates belong to Bacillus sp. and Pseudomonas sp. The study revealed the biocontrol and growth promoting potential of bacterial endophytes from H. brasiliensis., QC 20240703

Somatic Embryogenesis Receptor Kinase (SERK) genes are known to express during the transition of somatic cells to embryogenic cells, which have the capability to differentiate into somatic embryos at a later stage of development. In the past 20 years, SERK have drawn much research interest due to its crucial role in somatic embryogenesis. The aim of the current study was to isolate and characterize HbSERK gene through cDNA cloning and to perform comparative genomic analysis. The partial cDNA sequence of HbSERK was 408 bp in length and comparison with genomic sequence revealed the presence of two exons separated by one intron. In silico analysis of HbSERK predicted a protein of 136 amino acids that revealed high similarity (99%) to amino acid of AtSERK1. Multiple sequence alignment showed that HbSERK possessed partial sequences from the characteristic intracellular kinase domain containing the subdomains from V-X of the SERK family. Molecular phylogeny of HbSERK with SERK from other plant species showed that HbSERK was clustered most closely with AtSERK1 and MtSERK1., QC 20240703

Using dill (Anethum graveolens L.) as a model herb, we revealnovel associations between metabolite profile and sensory quality, by integrating non-target metabolomics with sensory data. Low night temperatures and exposure to UV-enriched light was used to modulate plant metabolism, thereby improving sensory quality. Plant age is a crucial factor associated with accumulation of dill ether and α-phellandrene, volatile compounds associated with dill flavour. However, sensory analysis showed that neither of these compounds has any strong association with dill taste. Rather, amino acids alanine, phenylalanine, glutamic acid, valine, and leucine increased in samples exposed to eustress and were positively associated with dill and sour taste. Increases in amino acids and organic acids changed the taste from lemon/grass to a more bitter/pungent dill-related taste. Our approach reveals a novel approach to establish links between effects of eustressors on sensory quality, and may be applicable to a broad range of crops., Funding Agencies:Faculty for Business, Science and Technology at Örebro University Örebro University Vice Chancellor's strategic research programme on 'Food and Health' Science Foundation Ireland S16/IA/4418

By cleaving peptide bonds, proteases either activate or degrade proteins and maintain protein quality control in response to various developmental stimuli and environmental factors. My work has focused on elucidating the role of the filamentation temperature sensitive protein H (FtsH) proteases. FtsHs belong to a membrane-embedded class of proteases found in eubacteria, animals and plants, which are located in the organelles of endosymbiosis (mitochondria and chloroplasts). They possess an AAA+ (ATPase associated with various cellular activities) and a peptidase M41 domain containing the HEXXH consensus sequence in the Zn2+ metalloprotease domain. FtsH proteases are known to form ring-like homo- or hetero-hexameric complexes. Arabidopsis thaliana, the model plant used in this study, contains seventeen AtFtsH proteases, of which twelve are presumably proteolytically active and five presumably proteolytic inactive members, known as AtFtsHi (i for inactive). In AtFtsHi members, the HEXXH motif is either deleted (AtFtsHi3) or mutated (AtFtsHi1, 2, 4, 5). Twelve AtFtsHs (AtFtsH 1, 2, 5–9, 11, 12 and AtFtsHi 1-5) are targeted to the chloroplast, whereas the remaining three (AtFtsH 3, 4 and 10) are mitochondrial. In Paper I, we demonstrate that AtFtsH12 interacts with AtFtsHi1, 2, 4, 5 to form a heteromeric complex. Abundance of these AtFtsH12-AtFtsHi complexes alters the accumulation of TIC (translocon on the inner chloroplast membrane) complexes. Transgenic mi12 (miRNA) knockdown plants that express lower amounts of AtFtsH12 displayed a pale-seedling and an aberrant chloroplast phenotype. mi12 plants displayed lowered total chlorophyll (Chla+Chlb) amount compared to wild type (WT), complementation lines and native AtFtsH12 promoter overexpressor (ox12) lines. Our biochemical studies identified drastic modifications in the total proteome of mi12 seedlings. N-terminome analyses of mi12 seedlings showed undisturbed plastidic protein maturation. In Paper II, we have shown th, Oregelbunden paginering / Various pagings. You can join the defence online via Zoom: https://umu.zoom.us/j/63199548197