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<jats:title>SUMMARY</jats:title><jats:p>The membrane‐bound heterotrimeric G‐proteins in plants play a crucial role in defending against a broad range of pathogens. This study emphasizes the significance of Extra‐large Gα protein 2 (XLG2), a plant‐specific G‐protein, in mediating the plant response to <jats:italic>Sclerotinia sclerotiorum</jats:italic>, which infects over 600 plant species worldwide. Our analysis of Arabidopsis G‐protein mutants showed that loss of <jats:italic>XLG2</jats:italic> function increased susceptibility to <jats:italic>S. sclerotiorum</jats:italic>, accompanied by compromised accumulation of jasmonic acid (JA) during pathogen infection. Overexpression of the <jats:italic>XLG2</jats:italic> gene in <jats:italic>xlg2</jats:italic> mutant plants resulted in higher resistance and increased JA accumulation during <jats:italic>S. sclerotiorum</jats:italic> infection. Co‐immunoprecipitation (co‐IP) analysis on <jats:italic>S. sclerotiorum</jats:italic> infected Col‐0 samples, using two different approaches, identified 201 XLG2‐interacting proteins. The identified JA‐biosynthetic and JA‐responsive proteins had compromised transcript expression in the <jats:italic>xlg2</jats:italic> mutant during pathogen infection. XLG2 was found to interact physically with a JA‐responsive protein, Coronatine induced 1 (CORI3) in Co‐IP, and confirmed using split firefly luciferase complementation and bimolecular fluorescent complementation assays. Additionally, genetic analysis revealed an additive effect of XLG2 and CORI3 on resistance against <jats:italic>S. sclerotiorum</jats:italic>, JA accumulation, and expression of the defense marker genes. Overall, our study reveals two independent pathways involving XLG2 and CORI3 in contributing resistance against <jats:italic>S. sclerotiorum</jats:italic>.</jats:p>

<jats:title>SUMMARY</jats:title><jats:p>During the oolong tea withering process, abiotic stresses induce significant changes in the content of various flavor substances and jasmonic acid (JA). However, the changes in chromatin accessibility during withering and their potential impact remain poorly understood. By integrating ATAC‐seq, RNA‐seq, metabolite, and hormone assays, we characterized the withering treatment‐induced changes in chromatin accessibility, gene expression levels, important metabolite contents, and JA and JA‐ILE contents. Additionally, we analyzed the effects of chromatin accessibility alterations on gene expression changes, content changes of important flavor substances, and JA hyperaccumulation. Our analysis identified a total of 3451 open‐ and 13 426 close‐differentially accessible chromatin regions (DACRs) under withering treatment. Our findings indicate that close‐DACRs‐mediated down‐regulated differentially expressed genes (DEGs) resulted in the reduced accumulation of multiple catechins during withering, whereas open‐DACRs‐mediated up‐regulated DEGs contributed to the increased accumulation of important terpenoids, JA, JA‐ILE and short‐chain C5/C6 volatiles. We further highlighted important DACRs‐mediated DEGs associated with the synthesis of catechins, terpenoids, JA and JA and short‐chain C5/C6 volatiles and confirmed the broad effect of close‐DACRs on catechin synthesis involving almost all enzymes in the pathway during withering. Importantly, we identified a novel MYB transcription factor (CsMYB83) regulating catechin synthesis and verified the binding of CsMYB83 in the promoter‐DACRs regions of key catechin synthesis genes using DAP‐seq. Overall, our results not only revealed a landscape of chromatin alters‐mediated transcription, flavor substance and hormone changes under oolong tea withering, but also provided target genes for flavor improvement breeding in tea plant.</jats:p>

<jats:title>SUMMARY</jats:title><jats:p>Potato (<jats:italic>Solanum tuberosum</jats:italic>) is a significant non‐grain food crop in terms of global production. However, its yield potential might be raised by identifying means to release bottlenecks within photosynthetic metabolism, from the capture of solar energy to the synthesis of carbohydrates. Recently, engineered increases in photosynthetic rates in other crops have been directly related to increased yield – how might such increases be achieved in potato? To answer this question, we derived the photosynthetic parameters <jats:italic>V</jats:italic><jats:sub>cmax</jats:sub> and <jats:italic>J</jats:italic><jats:sub>max</jats:sub> to calibrate a kinetic model of leaf metabolism (e‐Photosynthesis) for potato. This model was then used to simulate the impact of manipulating the expression of genes and their protein products on carbon assimilation rates <jats:italic>in silico</jats:italic> through optimizing resource investment among 23 photosynthetic enzymes, predicting increases in photosynthetic CO<jats:sub>2</jats:sub> uptake of up to 67%. However, this number of manipulations would not be practical with current technologies. Given a limited practical number of manipulations, the optimization indicated that an increase in amounts of three enzymes – Rubisco, FBP aldolase, and SBPase – would increase net assimilation. Increasing these alone to the levels predicted necessary for optimization increased photosynthetic rate by 28% in potato.</jats:p>

<jats:title>SUMMARY</jats:title><jats:p>Efficiently regulating growth to adapt to varying resource availability is crucial for organisms, including plants. In particular, the acquisition of essential nutrients is vital for plant development, as a shortage of just one nutrient can significantly decrease crop yield. However, plants constantly experience fluctuations in the presence of multiple essential mineral nutrients, leading to combined nutrient stress conditions. Unfortunately, our understanding of how plants perceive and respond to these multiple stresses remains limited. Unlocking this mystery could provide valuable insights and help enhance plant nutrition strategies. This review focuses specifically on the regulation of phosphorous homeostasis in plants, with a primary emphasis on recent studies that have shed light on the intricate interactions between phosphorous and other essential elements, such as nitrogen, iron, and zinc, as well as non‐essential elements like aluminum and sodium. By summarizing and consolidating these findings, this review aims to contribute to a better understanding of how plants respond to and cope with combined nutrient stress.</jats:p>

<jats:title>SUMMARY</jats:title><jats:p>The plastid terminal oxidase PTOX controls the oxidation level of the plastoquinone pool in the thylakoid membrane and acts as a safety valve upon abiotic stress, but detailed characterization of its role in protecting the photosynthetic apparatus is limited. Here we used PTOX mutants in two model plants <jats:italic>Arabidopsis thaliana</jats:italic> and <jats:italic>Marchantia polymorpha</jats:italic>. In Arabidopsis, lack of PTOX leads to a severe defect in pigmentation, a so‐called variegated phenotype, when plants are grown at standard light intensities. We created a green Arabidopsis PTOX mutant expressing the bacterial carotenoid desaturase CRTI and a double mutant in Marchantia lacking both PTOX isoforms, the plant‐type and the alga‐type PTOX. In both species, lack of PTOX affected the redox state of the plastoquinone pool. Exposure of plants to high light intensity showed in the absence of PTOX higher susceptibility of photosystem I to light‐induced damage while photosystem II was more stable compared with the wild type demonstrating that PTOX plays both, a pro‐oxidant and an anti‐oxidant role <jats:italic>in vivo</jats:italic>. Our results shed new light on the function of PTOX in the protection of photosystem I and II.</jats:p>

<jats:title>SUMMARY</jats:title><jats:p>Optimal grain‐appearance quality is largely determined by grain size. To date, dozens of grain size‐related genes have been identified. However, the regulatory mechanism of slender grain formation is not fully clear. We identified the OsSG34 gene by map‐based cloning. A 9‐bp deletion on 5’‐untranslated region of <jats:italic>OsSG34</jats:italic>, which resulted in the expression difference between the wild‐type and <jats:italic>sg34</jats:italic> mutant, led to the slender grains and good transparency in <jats:italic>sg34</jats:italic> mutant. OsSG34 as an α/β fold triacylglycerol lipase affected the triglyceride content directly, and the components of cell wall indirectly, especially the lignin between the inner and outer lemmas in rice grains, which could affect the change in grain size by altering cell proliferation and expansion, while the change in starch content and starch granule arrangement in endosperm could affect the grain‐appearance quality. Moreover, the <jats:italic>OsERF71</jats:italic> was identified to directly bind to <jats:italic>cis</jats:italic>‐element on the mutant site, thereby regulating the <jats:italic>OsSG34</jats:italic> expression. Knockout of three <jats:italic>OsSG34</jats:italic> homologous genes resulted in slender grains as well. The study demonstrated OsSG34, involved in lipid metabolism, affected grain size and quality. Our findings suggest that the <jats:italic>OsSG34</jats:italic> gene could be used in rice breeding for high yield and good grain‐appearance quality via marker‐assisted selection and gene‐editing approaches.</jats:p>

<jats:title>SUMMARY</jats:title><jats:p>Anionic phospholipids (PS, PA, PI, PIPs) are low‐abundant phospholipids with impactful functions in cell signaling, membrane trafficking and cell differentiation processes. They can be quickly metabolized and can transiently accumulate at defined spots within the cell or an organ to respond to physiological or environmental stimuli. As even a small change in their composition profile will produce a significant effect on biological processes, it is crucial to develop a sensitive and optimized analytical method to accurately detect and quantify them. While thin‐layer chromatography (TLC) separation coupled with gas chromatography (GC) detection methods already exist, they do not allow for precise, sensitive, and accurate quantification of all anionic phospholipid species. Here we developed a method based on high‐performance liquid chromatography (HPLC) combined with two‐dimensional mass spectrometry (MS<jats:sup>2</jats:sup>) by MRM mode to detect and quantify all molecular species and classes of anionic phospholipids in one shot. This method is based on a derivatization step by methylation that greatly enhances the ionization, the separation of each peak, the peak resolution as well as the limit of detection and quantification for each individual molecular species, and more particularly for PA and PS. Our method universally works in various plant samples. Remarkably, we identified that PS is enriched with very long chain fatty acids in the roots but not in aerial organs of <jats:italic>Arabidopsis thaliana</jats:italic>. Our work thus paves the way for new studies on how the composition of anionic lipids is finely tuned during plant development and environmental responses.</jats:p>

<jats:title>SUMMARY</jats:title><jats:p>Scots pine (<jats:italic>Pinus sylvestris</jats:italic> L.) is one of the most widespread and economically important conifer species in the world. Applications like genomic selection and association studies, which could help accelerate breeding cycles, are challenging in Scots pine because of its large and repetitive genome. For this reason, genotyping tools for conifer species, and in particular for Scots pine, are commonly based on transcribed regions of the genome. In this article, we present the Axiom Psyl50K array, the first single nucleotide polymorphism (SNP) genotyping array for Scots pine based on whole‐genome resequencing, that represents both genic and intergenic regions. This array was designed following a two‐step procedure: first, 192 trees were sequenced, and a 430K SNP screening array was constructed. Then, 480 samples, including haploid megagametophytes, full‐sib family trios, breeding population, and range‐wide individuals from across Eurasia were genotyped with the screening array. The best 50K SNPs were selected based on quality, replicability, distribution across the draft genome assembly, balance between genic and intergenic regions, and genotype–environment and genotype–phenotype associations. Of the final 49 877 probes tiled in the array, 20 372 (40.84%) occur inside gene models, while the rest lie in intergenic regions. We also show that the Psyl50K array can yield enough high‐confidence SNPs for genetic studies in pine species from North America and Eurasia. This new genotyping tool will be a valuable resource for high‐throughput fundamental and applied research of Scots pine and other pine species.</jats:p>

<jats:title>SUMMARY</jats:title><jats:p>The color of purple carrot taproots mainly depends on the anthocyanins sequestered in the vacuoles. Glutathione S‐transferases (GSTs) are key enzymes involved in anthocyanin transport. However, the precise mechanism of anthocyanin transport from the cytosolic surface of the endoplasmic reticulum (ER) to the vacuoles in carrots remains unclear. In this study, we conducted a comprehensive analysis of the carrot genome, leading to the identification of a total of 41 <jats:italic>DcGST</jats:italic> genes. Among these, <jats:italic>DcGST1</jats:italic> emerged as a prominent candidate, displaying a strong positive correlation with anthocyanin pigmentation in carrot taproots. It was highly expressed in the purple taproot tissues of purple carrot cultivars, while it was virtually inactive in the non‐purple taproot tissues of purple and non‐purple carrot cultivars. DcGST1, a homolog of <jats:italic>Arabidopsis thaliana</jats:italic> TRANSPARENT TESTA 19 (TT19), belongs to the GSTF clade and plays a crucial role in anthocyanin transport. Using the CRISPR/Cas9 system, we successfully knocked out <jats:italic>DcGST1</jats:italic> in the solid purple carrot cultivar ‘Deep Purple’ (‘DPP’), resulting in carrots with orange taproots. Additionally, DcMYB7, an anthocyanin activator, binds to the <jats:italic>DcGST1</jats:italic> promoter, activating its expression. Compared with the expression <jats:italic>DcMYB7</jats:italic> alone, co‐expression of <jats:italic>DcGST1</jats:italic> and <jats:italic>DcMYB7</jats:italic> significantly increased anthocyanin accumulation in carrot calli. However, overexpression of <jats:italic>DcGST1</jats:italic> in the two purple carrot cultivars did not change the anthocyanin accumulation pattern or significantly increase the anthocyanin content. These findings improve our understanding of anthocyanin transport mechanisms in plants, providing a molecular foundation for improving and enhancing carrot germplasm.</jats:p>

<jats:title>SUMMARY</jats:title><jats:p>Transcript stability is an important determinant of its abundance and, consequently, translational output. Transcript destabilisation can be rapid and is well suited for modulating the cellular response. However, it is unclear the extent to which RNA stability is altered under changing environmental conditions in plants. We previously hypothesised that recovery‐induced transcript destabilisation facilitated a phenomenon of rapid recovery gene downregulation (RRGD) in <jats:italic>Arabidopsis thaliana</jats:italic> (Arabidopsis) following light stress, based on mathematical calculations to account for ongoing transcription. Here, we test this hypothesis and investigate processes regulating transcript abundance and fate by quantifying changes in transcription, stability and translation before, during and after light stress. We adapt syringe infiltration to apply a transcriptional inhibitor to soil‐grown plants in combination with stress treatments. Compared with measurements in juvenile plants and cell culture, we find reduced stability across a range of transcripts encoding proteins involved in RNA binding and processing. We also observe light‐induced destabilisation of transcripts, followed by their stabilisation during recovery. We propose that this destabilisation facilitates RRGD, possibly in combination with transcriptional shut‐off that was confirmed for <jats:italic>HSP101</jats:italic>, <jats:italic>ROF1</jats:italic> and <jats:italic>GOLS1</jats:italic>. We also show that translation remains highly dynamic over the course of light stress and recovery, with a bias towards transcript‐specific increases in ribosome association, independent of changes in total transcript abundance, after 30 min of light stress. Taken together, we provide evidence for the combinatorial regulation of transcription and stability that occurs to coordinate translation during light stress and recovery in Arabidopsis.</jats:p>