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Plant growth and development are regulated by a tightly controlled interplay between cell division, cell expansion and cell differentiation during the entire plant life cycle from seed germination to maturity and seed propagation. To explore some of the underlying molecular mechanisms in more detail, we selected different aerial tissue types of the model plant Arabidopsis thaliana, namely rosette leaf, flower and silique/seed and performed proteomic, phosphoproteomic and transcriptomic analyses of sequential growth stages using tandem mass tag-based mass spectrometry and RNA sequencing. With this exploratory multi-omics dataset, development dynamics of photosynthetic tissues can be investigated from different angles. As expected, we found progressive global expression changes between growth stages for all three omics types and often but not always corresponding expression patterns for individual genes on transcript, protein and phosphorylation site level. The biggest difference between proteomic- and transcriptomic-based expression information could be observed for seed samples. Proteomic and transcriptomic data is available via ProteomeXchange and ArrayExpress with the respective identifiers PXD018814 and E-MTAB-7978.

Nitric oxide (NO) and nitrosylated derivatives are produced in peroxisomes, but the impact of NO metabolism on organelle functions remains largely uncharacterised. Double and triple NO-related mutants expressing cyan florescent protein (CFP)-SKL (nox1 × px-ck and nia1 nia2 × px-ck) were generated to determine whether NO regulates peroxisomal dynamics in response to cadmium (Cd) stress using confocal microscopy. Peroxule production was compromised in the nia1 nia2 mutants, which had lower NO levels than the wild-type plants. These findings show that NO is produced early in the response to Cd stress and was involved in peroxule production. Cd-induced peroxisomal proliferation was analysed using electron microscopy and by the accumulation of the peroxisomal marker PEX14. Peroxisomal proliferation was inhibited in the nia1 nia2 mutants. However, the phenotype was recovered by exogenous NO treatment. The number of peroxisomes and oxidative metabolism were changed in the NO-related mutant cells. Furthermore, the pattern of oxidative modification and S-nitrosylation of the catalase (CAT) protein was changed in the NO-related mutants in both the absence and presence of Cd stress. Peroxisome-dependent signalling was also affected in the NO-related mutants. Taken together, these results show that NO metabolism plays an important role in peroxisome functions and signalling., (© 2020 John Wiley & Sons Ltd.)

Background: Understanding developmental processes requires the unambiguous identification of cells and tissues, and the selective manipulation of the properties of those cells and tissues. Both requirements can most efficiently be satisfied through the use of GAL4/GFP enhancer-trap lines. No such lines, however, have been characterized for the study of early leaf development in the Columbia-0 reference genotype of Arabidopsis., Results: Here we address this limitation by identifying and characterizing a set of GAL4/GFP enhancer-trap lines in the Columbia-0 background for the specific labeling of cells and tissues during early leaf development, and for the targeted expression of genes of interest in those cells and tissues., Conclusions: By using one line in our set to address outstanding questions in leaf vein patterning, we show that these lines can be used to address key questions in plant developmental biology., (© 2020 Wiley Periodicals, Inc.)

The 'canalization hypothesis' was suggested 50 years ago by Tsvi Sachs to account for the formation of vascular strands in response to wounding or auxin application. The hypothesis proposes that positive feedback between auxin movement through a cell and the cell's auxin conductivity leads to the gradual selection of narrow 'canals' of polar auxin transport that will differentiate into vascular strands. Though the hypothesis has provided an invaluable conceptual framework to understand the patterned formation of vascular strands, evidence has been accumulating that seems to be incompatible with the hypothesis. We suggest that the challenging evidence is incompatible with current interpretations of the hypothesis but not with the concept at the core of the hypothesis' original formulation., (© 2020 The Authors. New Phytologist © 2020 New Phytologist Trust.)

A major challenge in plant developmental biology is to understand how plant growth is coordinated by interacting hormones and genes. To meet this challenge, it is important to not only use experimental data, but also formulate a mathematical model. For the mathematical model to best describe the true biological system, it is necessary to understand the parameter space of the model, along with the links between the model, the parameter space and experimental observations. We develop sequential history matching methodology, using Bayesian emulation, to gain substantial insight into biological model parameter spaces. This is achieved by finding sets of acceptable parameters in accordance with successive sets of physical observations. These methods are then applied to a complex hormonal crosstalk model for Arabidopsis root growth. In this application, we demonstrate how an initial set of 22 observed trends reduce the volume of the set of acceptable inputs to a proportion of 6.1 × 10-7 of the original space. Additional sets of biologically relevant experimental data, each of size 5, reduce the size of this space by a further three and two orders of magnitude respectively. Hence, we provide insight into the constraints placed upon the model structure by, and the biological consequences of, measuring subsets of observations.

Plants have excellent abilities to regenerate from detached tissues, in which various phytohormones play critical roles. It has been reported that jasmonate and auxin appeared sequentially during direct de novo root regeneration (DNRR) after leave detachment. However, the role of salicylic acid (SA) is still unknown in this procedure although it is another important plant hormone. We have demonstrated the potential of electrochemical sensors for real time screening of SA but the stability still needed to be improved. Herein a digital plotter was used to modify the carbon tape modified electrodes with pencil traces in order to improve the reproducibility. The modified electrodes in paper-based analytical devices were applied to monitor SA during direct DNRR. The drawing routines and the distances between two close traces were optimized. Our results showed that the carbon tape modified electrodes achieved more reproducible responses of SA. Combined with in vivo sampling, the results using our approach demonstrated that amounts of SA in the wild Arabidopsis thaliana leaves during direct DNRR reached highest at around 72 h after detachment and then decreased, implying that the wave of SA contents might follow that of auxin during direct DNRR. The application of the digital plotter offered a cost-effective and more reproducible method for preparation of disposable working electrodes, which might be extended for other biochemical assays., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Arabidopsis eceriferum (cer) mutants with unique alterations in their rosette leaf cuticular wax accumulation and composition established by gas chromatography have been investigated using attenuated total reflection (ATR)-Fourier transform infrared (FTIR) spectroscopy in combination with univariate and multivariate analysis. Objectives of this study were to evaluate the utility of ATR-FTIR for detection of chemical diversity in leaf cuticles, obtain spectral profiles of cer mutants in comparison with the wild type, and identify changes in leaf cuticles caused by drought stress. FTIR spectra revealed both genotype- and treatment-dependent differences in the chemical make-up of Arabidopsis leaf cuticles. Drought stress caused specific changes in the integrated area of the CH 3 peak, asymmetrical and symmetrical CH 2 peaks, ester carbonyl peak and the peak area ratio of ester CO to CH 2 asymmetrical vibration. CH 3 peak positively correlated with the total wax accumulation. Thus, ATR-FTIR spectroscopy is a valuable tool that can advance our understanding of the role of cuticle chemistry in plant response to drought and allow selection of superior drought-tolerant varieties from large genetic resources., (© 2019 John Wiley & Sons Ltd.)

The gaseous plant hormone ethylene can trigger myriad physiological and morphological responses in plants. While many ethylene signaling pathway components have been identified and characterized, little is known about the function of the integral membrane protein ETHYLENE-INSENSITIVE2 (EIN2), a central regulator of all ethylene responses. Here, we demonstrate that Arabidopsis thaliana EIN2 is a protein with a short half-life that undergoes rapid proteasome-mediated protein turnover. Moreover, EIN2 protein accumulation is positively regulated by ethylene. We identified two F-box proteins, EIN2 TARGETING PROTEIN1 (ETP1) and EIN2 TARGETING PROTEIN2 (ETP2), that interact with the EIN2 C-terminal domain (EIN2-CEND), which is highly conserved and sufficient to activate most ethylene responses. Overexpression of ETP1 or ETP2 disrupts EIN2 protein accumulation, and these plants manifest a strong ethylene-insensitive phenotype. Furthermore, knocking down the levels of both ETP1 and ETP2 mRNAs using an artificial microRNA (amiRNA) leads to accumulation of EIN2 protein, resulting in plants that display constitutive ethylene response phenotypes. Finally, ethylene down-regulates ETP1 and ETP2 proteins, impairing their ability to interact with EIN2. Thus, these studies reveal that a complex interplay between ethylene, the regulation of ETP1/ETP2 F-box proteins, and subsequent targeting and degradation of EIN2 is essential for triggering ethylene responses in plants. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) tolerance seems to be a constitutive species-level trait in Arabidopsis halleri. In order to identify genes potentially implicated in Cd tolerance, a backcross (BC1) segregating population was produced from crosses between A. halleri ssp. halleri and its closest non-tolerant relative A. lyrata ssp. petraea. The most sensitive and tolerant genotypes of the BC1 were analysed on a transcriptome-wide scale by cDNA-amplified fragment length polymorphism (AFLP). A hundred and thirty-four genes expressed more in the root of tolerant genotypes than in sensitive genotypes were identified. Most of the identified genes showed no regulation in their expression when exposed to Cd in a hydroponic culture medium and belonged to diverse functional classes, including reactive oxygen species (ROS) detoxification, cellular repair, metal sequestration, water transport, signal transduction, transcription regulation, and protein degradation, which are discussed. [ABSTRACT FROM PUBLISHER]

Plant secretory phospholipases A2 (sPLA2s) probably play important roles in phospholipid signaling based on the data reported from other organisms, but their functions are poorly understood because of the lack of cloned sPLA2 genes. In this study, we cloned and characterized an Arabidopsis secretory phospholipase A2-γ (AtsPLA2-γ) cDNA, and examined its enzymatic properties. The recombinant protein of AtsPLA2-γ showed maximal enzyme activity at pH 8.0, and required Ca2+ for activity. Moreover, AtsPLA2-γ showed sn-2 position specificity but no prominent acyl preference, though it showed head group specificity to phosphatidylethanolamine rather than to phosphatidylcholine. AtsPLA2-γ was found to predominate in the mature flower rather than in other tissues, and subcellular localization analysis confirmed that AtsPLA2-γ is secreted into the intercellular space. [Copyright &y& Elsevier]

Regulation of tetrapyrrole biosynthesis in higher plants has been attributed to negative feedback control of steps prior to δ-aminolevulinic acid (ALA) formation. One of the first mutants with a defect in this control had been identified in barley. The tigrina (tig) d mutant accumulates 10–15-fold higher amounts of protochlorophyllide than wild type, when grown in the dark. The identity of the TIGRINA d protein and its mode of action are not known yet. Initially this protein had been proposed to act as a repressor of genes that encode enzymes involved in early steps of ALA formation, but subsequent attempts to confirm this experimentally failed. Here we demonstrate that the TIGRINA d gene of barley is an ortholog of the FLU gene of Arabidopsis thaliana. The FLU protein is a nuclear-encoded plastid protein that plays a key role in negative feedback control of chlorophyll biosynthesis in higher plants. Sequencing of the FLU gene of barley revealed a frame shift mutation in the FLU gene of the tig d mutant that results in the loss of two tetratricopeptide repeats that in the FLU protein of Arabidopsis are essential for its biological activity. This mutation cosegregates strictly with the tigrina phenotype within the F1 population of a heterozygous tig d mutant, thus providing additional support for the flu gene being responsible for the tigrina phenotype of barley. [Copyright &y& Elsevier]

A cinnamoyl-CoA reductase 1 knockout mutant in Arabidopsis thaliana was investigated for the consequences of lignin synthesis perturbation on the assembly of the cell walls. The mutant displayed a dwarf phenotype and a strong collapse of its xylem vessels corresponding to lower lignin content and a loss of lignin units of the noncondensed type. Transmission electron microscopy revealed that the transformation considerably impaired the capacity of interfascicular fibers and vascular bundles to complete the assembly of cellulose microfibrils in the S(2) layer, the S(1) layer remaining unaltered. Such disorder in cellulose was correlated with X-ray diffraction showing altered organization. Semi-quantitative immunolabeling of lignins showed that the patterns of distribution were differentially affected in interfascicular fibers and vascular bundles, pointing to the importance of noncondensed lignin structures for the assembly of a coherent secondary wall. The use of laser capture microdissection combined with the microanalysis of lignins and polysaccharides allowed these polymers to be characterized into specific cell types. Wild-type A. thaliana displayed a two-fold higher syringyl to guaiacyl ratio in interfascicular fibers compared with vascular bundles, whereas this difference was less marked in the cinnamoyl-CoA reductase 1 knockout mutant.

In flowering plants, the interaction of pollen tubes with female tissues is important for the accomplishment of double fertilization. Little information is known about the mechanisms that underlie signalling between pollen tubes and female tissues. In this study, two Arabidopsis pollen tube-expressed CrRLK1L protein kinases, Buddha's Paper Seal 1 (BUPS1) and BUPS2, were identified as being required for normal tip growth of pollen tubes in the pistil. They are expressed prolifically in pollen and pollen tubes and are localized on the plasma membrane of the pollen tube tip region. Mutations in BUPS1 drastically reduced seed set. Most of the bups1 mutant pollen tubes growing in the pistil exhibited a swollen pollen tube tip, leading to failure of fertilization. The bups2 pollen tubes had a slightly abnormal morphology but could still accomplish double fertilization. The bups1 bups2 double mutant exhibited a slightly enhanced phenotype compared to the single bups1 mutants. The BUPS1 proteins could form homomers and heteromers with BUPS2, whereas BUPS2 could only form heteromers with BUPS1. The BUPS proteins could interact with the Arabidopsis pollen-expressed RopGEFs in the yeast two-hybrid (Y2H) and bimolecular fluorescence complementation (BiFC) assays. The results indicated that the BUPSs may mediate normal polar growth of pollen tubes in the pistil., (© 2018 The Authors The Plant Journal © 2018 John Wiley & Sons Ltd.)

Pathogenesis-related proteins (PR), whose expressions are induced by biotic and abiotic stress, play important roles in plant defense. Previous research identified the salt-induced HcPR10 gene in the halophyte Halostachys caspica as a regulator of plant growth and development through interactions with cytokinin. However, the mechanisms by which HcPR10 mediates resistance to abiotic stress remain poorly understood. In this study, we found that the heterologous expression of HcPR10 significantly enhanced salt and drought tolerance in Arabidopsis, likely by increasing the activity of antioxidant enzyme systems, allowing for effective scavenging of reactive oxygen species (ROS) and thus protecting plant cells from oxidative damage. Additionally, the overexpression of HcPR10 also activated the expression of stress-related genes in Arabidopsis. Furthermore, using yeast two-hybrid technology, five proteins (HcLTPG6, HcGPX6, HcUGT73B3, HcLHCB2.2, and HcMSA1) were identified as potential interacting partners for HcPR10, which could positively regulate the salt stress response mediated by HcPR10. Our findings lay the foundation for a better understanding of the molecular mechanisms of HcPR10 in response to abiotic stress and reveal additional candidate genes for improving crop salt tolerance through genetic engineering., Competing Interests: Declarations. Conflict of interest: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024. The Author(s), under exclusive licence to Springer Nature B.V.)

GLABRA1 (GL1), which encodes an R2R3 MYB transcription factor, is a key regulator of trichome patterning in the aerial organs of Arabidopsis (Arabidopsis thaliana). Although it has been generally assumed that GL1 functions exclusively in shoots and is not expressed in roots, reverse transcription polymerase chain reaction (RT-PCR) analysis has revealed that GL1 is indeed expressed in roots. To investigate whether GL1 plays a role in root epidermal patterning, we analyzed the effects of gl1 mutations in sensitized genetic backgrounds. Our findings show that gl1 mutants enhance the root epidermal phenotype of a weak allele of the werewolf (wer) mutant and suppress the phenotype of the caprice (cpc) mutant. We also demonstrate that the GL1 promoter is active in N-position epidermal cells, and that the GFP-GL1 fusion protein is predominantly localized in the nucleus of N-position cells. Furthermore, we provide evidence that GL1 expression is positively regulated by WER, GLABRA3, ENHANCER OF GLABRA3, and TRANSPARENT TESTA GLABRA1, while negatively regulated by CPC, TRIPTYCHON, and GLABRA2 (GL2). Notably, GL2, which is positively regulated by GL1, moderately represses GL1 expression, and both GL1 and GL2 are positively regulated by WER in N-position cells. These findings suggest that a negative feedback regulation of GL1 expression via GL2 contributes to the fine-tuning of non-hair cell fate determination in Arabidopsis root epidermis., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Nickel (Ni) is an important micronutrient, but excess Ni is toxic to many plant species. Currently, relatively little is known about the genetic basis of the plant responses to Ni toxicity. Here, we demonstrate that NAC32 transcription factor functions as a core genetic hub to regulate the Ni toxicity responses in Arabidopsis. NAC32 negatively regulates root-Ni concentration through the IREG2 (IRON REGULATED2) encoding a transporter. NAC32 also induces local auxin biosynthesis in the root-apex transition zone by upregulating YUCCA 7 (YUC7)/8/9 expression, which results in a local enhancement of auxin signaling in root tips, especially under Ni toxicity, thereby impaired primary root growth. By analyses of various combinations of nac32 and ireg2 mutants, as well as nac32 and yuc7/8/9 triple mutants, including high-order quadruple mutant, we demonstrated that NAC32 negatively regulates Ni stress tolerance by acting upstream of IREG2 and YUC7/8/9 to modulate their function in Ni toxicity responses. ChIPqPCR, EMSA (electrophoretic mobility shift assay) and transient dual-LUC reporter assays showed that NAC32 transcriptionally represses IREG2 expression but activates YUC7/8/9 expression by directly binding to their promoters. Our work demonstrates that NAC32 coordinates Ni compartmentation and developmental plasticity in roots, providing a conceptual framework for understanding Ni toxicity responses in plants., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Cadmium (Cd) pollution poses a significant ecological risk to mangrove ecosystems. Trehalose has excellent potential to mitigate the adverse effects of heavy metals. Unfortunately, the mechanisms related to trehalose-mediated heavy metal tolerance in plants remain elusive. In the present study, we firstly found that Cd induced the accumulation of trehalose and the differential expression of trehalose biosynthesis genes in the roots of mangrove plant Avicennia marina. Then, we found that the application of exogenous trehalose could alleviate the negative effects of Cd on A. marina by phenotypic observation. In addition, photosynthetic parameters and cellular ultrastructure analyses demonstrated that exogenous trehalose could improve the photosynthesis and stabilize the chloroplast and nuclear structure of the leaves of A. marina. Besides, exogenous trehalose could inhibit the Cd 2+ influx from the root to reduce the Cd 2+ content in A. marina. Subsequently, substrate sensitivity assay combined with ion uptake analysis using yeast cells showed that several trehalose biosynthesis genes may have a regulatory function for Cd 2+ transport. Finally, we further identified a positive regulatory factor, AmTPS6, which enhances the Cd tolerance in transgenic Arabidopsis thaliana. Taken together, these findings provide new understanding to the mechanism of Cd tolerance in mangrove A. marina at trehalose aspect and a theoretical basis for the conservation of mangroves in coastal wetlands., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The Ni hyperaccumulator Odontarrhena chalcidica (formerly Alyssum murale), exhibits a significant capacity to accumulate Zn in the roots. However, the molecular mechanisms underlying the variation in Ni and Zn accumulation are poorly understood. Here, we isolated a homolog of heavy metal ATPase 3 from O. chalcidica (OcHMA3) and characterized its functions using heterologous systems. Phylogenetic analysis revealed that OcHMA3 protein shares 87.6 % identity with AtHMA3, with similar metal binding sites to other HMA3 proteins. Heterologous expression of OcHMA3 in yeast increased sensitivity to Cd, Ni and Zn, suggesting it functions as a broad-specificity transporter. Further investigation showed OcHMA3 is constitutively expressed in the roots and localized to the tonoplast. Overexpression of OcHMA3 in A. thaliana shoots increased its roots Zn concentrations by 41.9 % - 74.1 %. However, overexpression of OcHMA3 in roots enhanced its tolerance to Cd and increased roots Cd concentrations by 50.9 % - 90.6 %. Our findings indicated OcHMA3 is responsible for Zn sequestration in root vacuoles, likely leading to Zn retention in roots and subsequent Ni hyperaccumulation in shoots. This study elucidates the molecular mechanism of Ni and Zn accumulation in O. chalcidica, and identifies OcHMA3 as a potential gene for developing Zn-rich plants and for phytoextraction in Cd-contaminated soils., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Sucrose transporter (SUT) plays essential roles in plant growth and development, as well as responses to diverse abiotic stresses. However, limited information about the function of SUT was available in pineapple, an important tropical fruit crop with crassulacean acid metabolism. Here, four AcSUT genes were identified in pineapple genome, and divided into three clades according to the phylogenetic analysis. The expression profiles of AcSUTs were systemically examined, and they were all localized to plasma membrane. Transport activity assay by two-electrode voltage clamp of Xenopus oocytes showed that AcSUT1A and AcSUT1B were capable of transporting a range of glucosides, and they were exhibited high affinity for sucrose with Km value of 0.09 mM and 0.41 mM at pH 5.0, respectively. Overexpression of the cold-induced AcSUT1B conferred enhanced cold tolerance in transgenic Arabidopsis. DNA-protein interaction analysis further demonstrated that AcCBF1 directly binds the CRT/DRE element of the AcSUT1B promoter and activated its expression. Heterologous expression of AcCBF1 in Arabidopsis also increased cold tolerance. In this study, we investigated the transport activities of AcSUTs in pineapple and identified the AcCBF1-AcSUT1B module involved in cold stress, which provided new insights into the molecular mechanism of the cold response in pineapple., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Elucidating gene function is one of the ultimate goals of plant science. Despite this, only ∼15 % of all genes in the model plant Arabidopsis thaliana have comprehensively experimentally verified functions. While bioinformatical gene function prediction approaches can guide biologists in their experimental efforts, neither the performance of the gene function prediction methods nor the number of experimental characterization of genes has increased dramatically in recent years. In this review, we will discuss the status quo and the trajectory of gene function elucidation and outline the recent advances in gene function prediction approaches. We will then discuss how recent artificial intelligence advances in large language models and knowledge graphs can be leveraged to accelerate gene function predictions and keep us updated with scientific literature., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Marek Mutwil reports financial support was provided by Singaporean Ministry of Education. Rohan Shawn Sunil reports financial support was provided by Singaporean Ministry of Education. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Antimony (Sb) is a toxic pollutant, with Sb(V) being one of its main forms in the environment, but the process and mechanism of plant uptake of Sb(V) remain unclear. To investigate the process of Sb(V) uptake by plants, Arabidopsis thaliana plants were exposed to water culture media supplemented with different Sb(V) concentrations. The distribution, content, and forms of Sb(V) in Arabidopsis roots, and the accumulation and fixation of Sb(V) in Arabidopsis plants were studied. In addition, inhibitor experiments and analyses of gene expression changes were conducted to elucidate the underlying mechanism of its toxicity. Sb(V) entering the roots was mainly adsorbed on the cell wall, and the Sb(V) content in both apoplastic solution and symplastic solution increased with increasing external Sb(V) concentration. Sb(V) concentration in apoplast and symplast were approximately linearly correlated (R 2 =0.980), indicating low affinity of cells for Sb(V) absorption. Moreover, uncouplers significantly inhibited the entry of Sb(V) into the symplast, suggesting that the transmembrane transport of Sb(V) is energy-consuming. Sb(V) entering the cell could be partially reduced to Sb(III), and significant changes in glutathione metabolism gene expression were detected, indicating the important role of glutathione metabolism in the detoxification of Sb(V). From the perspective of the whole plant, although Sb(V) is absorbed by the roots, it is mainly fixed in the leaves and stems. This study revealed the pattern of Sb(V) uptake by plants and elucidated the mechanism of Sb(V) uptake by plants from the perspectives of kinetics, physiology, and genetics., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

The plant elongation factor eEF1A is involved in coregulating not only the translation of proteins and controlling translation-related signaling but also in signaling associated with cell growth, stress response and motility, controlling apoptosis and responding to adversity in plants. In this study, four eEF1A genes, namely, ClEF1A-1, ClEF1A-2, ClEF1A-3 and ClEF1A-4, were identified from the genomic and ubiquitin-modified omics data of the 'Xiangshui Lemon', and bioinformatics analysis revealed that these four genes have relatively similar structures with conserved sequences; ClEF1A-1 and ClEF1A-4 were highly expressed in pollen, and temporal expression analysis demonstrated that the expression of ClEF1As was significantly greater under self-pollination than under cross-pollination. All four genes were localized in the nucleus. ClEF1As overexpression promoted early flowering and improved drought and salt stress tolerance in transgenic Arabidopsis plants. Yeast two-hybrid assays revealed that ClEF1As interacted with F-box, eIF3-G, the organ-specific-like protein S2, AGL62, S 1 -RNase, S 2 -RNase, S 3 -RNase and S 4 -RNase. This study demonstrated the functions of ClEF1As and provided a baseline for further studies on the associations of ClEF1As with self-incompatibility and abiotic stresses., Competing Interests: Declaration of competing interest We declare that we have no financial and personal relationships with other people or organizations that can inappropriately influence our work, there is no professional or other personal interest of any nature or kind in any product, service and/or company that could be construed as influencing the position presented in, or the review of, the manuscript entitled “Four ClEF1A genes involved in self-incompatibility in 'Xiangshui Lemon' confer early fowering and increase stress tolerance in transgenic Arabidopsis”. All authors have seen the manuscript and approved the submittal to your journal. None of the material in the paper has been published or is under consideration for publication elsewhere., (Copyright © 2024 Elsevier Masson SAS. All rights reserved.)

The UDP-glucose 4-epimerase (UGE) enzyme plays a critical role in plant growth and responses to abiotic stressors, such as heavy metal exposure. However, UGE-mediated remodeling of cell wall polysaccharides in response to these stressors remains poorly understood in willow. This study investigated the structure, function, and expression patterns of the UGE gene family in willow, focusing on cadmium treatment to elucidate how SpUGE1 enhances Cd resistance. Six SpUGE genes were identified through whole-genome sequencing and bioinformatics analysis, and they were mapped across five chromosomes. Quantitative PCR analysis revealed that, with the exception of SpUGE3, all genes showed their highest relative expression in the leaves. Under Cd treatment, members of the SpUGE gene family displayed varying levels of responsiveness, with SpUGE1 showing a marked increase in expression over time. In transgenic Arabidopsis thaliana overexpressing SpUGE1, the cellulose, hemicellulose, lignin, and pectin content significantly increased, with cellulose levels rising by >50 % and pectin by approximately 30 %. This overexpression conferred enhanced Cd resistance by increasing cell wall thickness through elevated cell wall polysaccharides, which reduced Cd uptake. Consequently, Cd content in the cell wall, chloroplasts, and mitochondria was significantly lower than that in wild-type plants, reducing cellular damage and improving Cd resistance. Overall, this study provides valuable theoretical and experimental insights into the role of the SpUGE1 gene family in willow., Competing Interests: Declaration of competing interest The authors declare no known competing financial interests or personal relationships that could influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Gravitropism is crucial for plants to secure light, water, and minerals essential for developing seedlings. Despite its importance, the gravitropism of young roots remains largely unexplored. Herein, we reported that the emerging Arabidopsis roots exhibit hypersensitive gravitropism compared to mature roots, growing relatively slowly but bending exceptionally rapidly. This rapid gravibending is characterized by substantial growth inhibition and a distinctive auxin accumulation on the lower side of the elongation zone. Intriguingly, surgical experiments suggest that these auxins predominantly originate from the elongation zone rather than from the shoot or root cap. However, their asymmetrical distribution is heavily modulated by the root cap. Confocal analysis of GFP-tagged TAA1 further confirms that gravitational stimulus induces active auxin biosynthesis in the elongation zone of nascent roots but not in mature roots. Furthermore, mutations in the PIN proteins, especially PIN2, severely impair the rapid gravitropic responses in emerging roots. Interestingly, PIN2 in nascent roots is not confined to the epidermis and cortex but extends to the endodermis, contrasting with its distribution in mature roots. Gravitational stimulation leads to a marked asymmetrical distribution of PIN2 between the upper and lower sides of the roots, which is strongly inhibited by surgical removal of the root cap. These observations indicate that gravitational stimulation triggers active auxin synthesis and PIN protein-mediated lateral transport within the elongation zone of emerging roots, resulting in swift gravitropic responses. These results offer an intriguing enhancement and expansion to the mechanism of root gravitropism., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Masson SAS. All rights reserved.)

The light irradiation to the plant chloroplasts drives NADPH and ATP synthesis in the stroma via the electron transport chains within the thylakoid membranes. Conventional methods for assessing photosynthetic light reactions are often invasive or require specific conditions. While detection markers do not significantly affect plant growth itself, developing a method for the real-time and non-invasive detection of NADPH is a highly impactful and important research area in plant physiology and biochemistry. This study introduces a genetically encoded NADPH-binding blue fluorescent protein (mBFP) targeted to the chloroplast stroma or thylakoid membrane in Arabidopsis thaliana and Nicotiana benthamiana. Using two-photon microscopy, we monitored real-time stromal NADPH levels in transgenic leaves of Arabidopsis in response to light exposure. A mutant mBFP construct targeted to the thylakoid membrane allowed us to detect the stromal NADPH levels in real time under different light conditions. This in planta biosensor provides a non-invasive tool for studying photosynthetic responses to light more quantitatively and holds potential for optimizing light conditions in controlled-environment agriculture, such as indoor vertical farms, to improve crop productivity., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Masson SAS. All rights reserved.)

Foxtail millet is a C 4 crop rich in folate (FA). This study explores the roles of the 4-amino-4-deoxychorismate lyase (ADCL) - a member of the transaminase IV group of enzymes - in FA metabolism and conferred phenotypes. Phylogenetic comparisons identified diversity in the transaminase IV/ADCL gene family in the foxtail millet genome which was associated with genomic duplications. Molecular docking studies suggested that SiADCL1 bound most strongly to aminodeoxychorismate (ADC) and most likely had the highest catalytic activities. SiADCL1 which was highly expressed in roots, peduncles and flag leaves. Over-expression of SiADCL1 in Arabidopsis significantly increased total FA content (1.14-1.84 fold) and this was linked to a delayed flowering time. Metabolomic and transcriptomic characterization of the derived over-expression lines, found that FA promotes the change of methylation-related genes, ethylene synthesis, amino acid metabolism and flowering-related genes. This study revealed a potential gene coexpression network linked with FA and targeted key genes that could be exploited in foxtail millet breeding programs., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Masson SAS. All rights reserved.)

The use of nitrogen (N) fertilizers increases crop yield, but the accumulation of residual N in agricultural soils poses significant environmental risks. Improving the N use efficiency (NUE) of crops can help reduce N pollution. While nanomaterials have been shown to enhance crop agronomic traits, more research is needed to clarify the regulatory mechanisms involved. In this study, foliar spraying of carbon dots (CDs, 1 mg mL -1 ) derived from Salvia miltiorrhiza increased the activity of plasma membrane H + -ATPase in Arabidopsis thaliana roots, promoting the uptake, transport, and assimilation of NO 3 - and NH 4 + . The upregulation of N metabolism-related genes, such as AtAMTs and AtNRTs, was also observed in A. thaliana roots. Transcriptome analysis suggested that this regulatory effect is mediated by the shoot-to-root mobile polypeptide CEPD1 (C-terminally encoded peptide DOWNSTREAM 1) signaling pathway. Additionally, foliar application of CDs increased the NUE of sweetpotato (Ipomoea batatas (L.) Lam.) from 2.5% to 8.1%. The upregulation of genes such as CEPD1 in leaves was observed following CDs application under different N conditions. Finally, foliar spraying of CDs significantly increased field yield and enhanced tolerance to low N stress in sweetpotato. Overall, this study demonstrated that foliar application of CDs improved NUE in plants through CEPD1-dependent signaling., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Masson SAS. All rights reserved.)

Protein ubiquitination is a critical post-translational modification (PTM) involved in diverse biological processes and plays a pivotal role in regulating physiological mechanisms and disease states. Despite various efforts to develop ubiquitination site prediction tools across species, these tools mainly rely on predefined sequence features and machine learning algorithms, with species-specific variations in ubiquitination patterns remaining poorly understood. This study introduces a novel approach for predicting Arabidopsis thaliana ubiquitination sites using a neural network model based on knowledge distillation and natural language processing (NLP) of protein sequences. Our framework employs a multi-species "Teacher model" to guide a more compact, species-specific "Student model", with the "Teacher" generating pseudo-labels that enhance the "Student" learning and prediction robustness. Cross-validation results demonstrate that our model achieves superior performance, with an accuracy of 86.3 % and an area under the curve (AUC) of 0.926, while independent testing confirmed these results with an accuracy of 86.3 % and an AUC of 0.923. Comparative analysis with established predictors further highlights the model's superiority, emphasizing the effectiveness of integrating knowledge distillation and NLP in ubiquitination prediction tasks. This study presents a promising and efficient approach for ubiquitination site prediction, offering valuable insights for researchers in related fields. The code and resources are available on GitHub: https://github.com/nuinvtnu/KD_ArapUbi., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Olive oil production generates substantial quantities of pomace, which are often disposed of in soil, leading to adverse effects on agriculture and the environment. Furthermore, climate change exacerbates plant diseases and promotes the use of toxic phytochemicals in agriculture. However, olive mill wastes can have high potential as reusable and valuable bioresources. Using diluted ethanol, an environmentally friendly solvent, we extracted a fraction containing short and long oligogalacturonides, short arabino-oligosaccharides and polysaccharides. The obtained extract elicited key features of plant innate immunity in Arabidopsis seedlings, including the phosphorylation of mitogen-activated protein kinases MPK3 and MPK6 and the upregulation of defence genes such as CYP81F2, WRKY33, WRKY53, and FRK1. Notably, pretreatment of adult Arabidopsis and tomato plants with the olive pomace extract primed defence responses and enhanced their resistance to the phytopathogens Botrytis cinerea and Pseudomonas syringae. Our results highlight the opportunity to upcycle the two-phase olive pomace collected at the late stage of olive oil campaign, in low-cost and sustainable glycan elicitors, contributing to reducing the use of chemically synthesized pesticides., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Currently, little is known regarding the specific processes through which brassinosteroids (BR) affect arbuscular mycorrhizal (AM) symbiosis. Understanding this relationship is vital for advancing plant physiology and agricultural applications. In this study, we aimed to elucidate the regulatory mechanisms of BR in AM symbiosis. According to the log2 fold change-value and adjP-value, we integrated the common differentially expressed genes (DEGs) in maize (Zea mays L.) treated with BR and AM, Arabidopsis (Arabidopsis thaliana) mutants deficient in BR receptors, and tomato (Solanum lycopersicum) plants inoculated with AM fungi. In addition, we characterized the symbiotic performance of tomato plants with BR receptor defects and overexpression. The results indicated that the common differential genes induced by BR and AM were involved in metabolic processes, such as cell wall modification, cytoskeleton remodeling, auxin and ethylene signaling, photosynthesis, mineral nutrient transport, and stress defense. Specifically, these include the BR1 gene, which modifies the cell wall. However, the fungal colonization rate of BR receptor-deficient tomato plants was significantly reduced, and the total phosphorus concentration was increased. Conversely, the performance of the overexpressing tomato transformation plants demonstrated a significant contrast. Additionally, the mild rescue of mycorrhizal attenuation in mutants treated with exogenous BR suggests the possibility of direct feedback from BR synthesis to AM. Notably, the cell wall modification gene (SlBR1) and calcium spike gene (SlIPD3) were induced by both BR and AM, suggesting that BR may influence cell penetration during the early stages of AM colonization. Synthesis: Our results demonstrated that BR positively regulates AM symbiosis through multiple pathways. These findings pave the way for future research, including isolation of the individual contributions of each pathway to this complex process and exploration of possible agricultural applications., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier GmbH. All rights reserved.)

Arginine is an important amino acid in plants, as it not only plays a structural role and serves as nitrogen storage but is also a precursor for various molecules, including polyamines and proline. Arginine is produced by argininosuccinate lyase (ASL) which catalyzes the cleavage of argininosuccinate to arginine and fumarate. ASL belongs to the fumarate lyase family and while many members of this family were well-characterized, little is known about plant ASLs. Here we present the first crystal structures of ASL from the model plant, Arabidopsis thaliana (AtASL). One of the structures represents the unliganded form of the AtASL homotetramer. The other structure, obtained from a crystal soaked in argininosuccinate, accommodates the substrate or the reaction products in one of four active sites of the AtASL tetramer. Each active site is located at the interface of three neighboring protomers. The AtASL structure with ligands allowed us to analyze the enzyme-substrate and the enzyme-product interactions in detail. Furthermore, based on our analyses, we describe residues of AtASL crucial for catalysis. The structure of AtASL gives the rationale for the open-to-close transition of the GSS mobile loop and indicates the importance of serine 333 from this loop for the enzymatic action of the enzyme. Finally, we supplemented the structural data with the identification of sequence motifs characteristic for ASLs., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

The NPR1 (nonexpressor of pathogenesis-related genes 1) is a key regulator of the salicylic-acid-mediated immune response caused by pathogens in Arabidopsis thaliana. Mutations C150Y and H334Y in the BTB/ANK domains of NPR1 inhibit the defense response, and transcriptional co-activity with enhanced disease susceptibility 1 (EDS1) has been revealed experimentally. This study examined the conformational changes and reduced NPR1-EDS1 interaction upon mutation using a molecular dynamics simulation. Initially, BTB C150Y NPR1 and ANK H334Y NPR1 were categorized as pathological mutations rather than others based on sequence conservation. A distant ortholog was used to map the common residues shared among the wild-type because the mutations were highly conserved. Overall, 179 of 373 residues were determining the secondary structures and fold versatility of conformations. In addition, the mutational hotspots Cys150, Asp152, Glu153, Cys155, His157, Cys160, His334, Arg339 and Lys370 were crucial for oligomer-to-monomer exchange. Subsequently, the atomistic simulations with free energy (MM/PB(GB)SA) calculations predicted structural displacements engaging in the N-termini α5 133-178 α7 linker connecting the central ANK regions ( α13 260-290 α14 and α18 320-390 α22 ), where prominent long helices (α5 16 ) and short helices (α3 10 ) replaced with β-turns and loops disrupting hydrogen bonds and salt bridges in both mutants implicating functional regulation and activation. Furthermore, the mutation repositions the intact stability of multiple regions ( L13 C149-N356 α20 BTB/ANK - α17 W301-E357 α21 N-ter/coiled-coil ) compromising a dynamic interaction of NPR1-EDS1. By unveiling the transitions between the distinct functions of mutational perception, this study paves the way for future investigation to orchestrate additive host-adapted transcriptional reprogramming that controls defense-related regulatory mechanisms of NPR1s in plants., Competing Interests: Declaration of competing interest The authors declares that there is no conflict of interest regarding the publication of this paper., (Copyright © 2024 Elsevier GmbH. All rights reserved.)

Phloretin is a key secondary metabolite produced by apple trees. Known for its strong antioxidant properties, this dihydrochalcone has been extensively studied in animals but less so in plants. Recently, we identified phloretin as a phytotoxic allelochemical that inhibits growth in the model plant Arabidopsis by disrupting auxin metabolism and distribution in the roots. In this study, we found that phloretin significantly hinders the growth of Arabidopsis seedlings' aerial parts after a short-term treatment (10 days) and causes their decay after long-term exposure (28 days). These effects result from ultrastructural damage in the mesophyll cells of the leaves, including chloroplast displacement and swelling, lesions, and alterations in thylakoid and cell wall organization. Interestingly, phloretin-treated plants showed a decrease in malondialdehyde levels and antioxidant enzyme activities, while hydrogen peroxide and proline levels remained unchanged. This suggests that phloretin-induced chlorosis and seedling decay are not due to oxidative stress but rather to severe chloroplast structural damage, leading to inefficient photosynthesis, starch degradation, starvation, and activation of micro- and macroautophagic processes for self-preservation. Ultimately, these processes result in programmed cell death. These new insights into the phytotoxic effects of phloretin on Arabidopsis shoots could pave the way for future research into phloretin as a potential multitarget bioherbicide and enhance our understanding of autoallelopathy in apple trees., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier GmbH. All rights reserved.)

Plants can sense and respond to non-damaging mechanical stimulation such as touch, rain, or wind. Mechanical stimulation induces an increase of cytosolic calcium ([Ca 2+ ] cyt ), accumulation of phytohormones from the group of jasmonates (JAs) and activation of gene expression, which can be JAs-dependent or JAs-independent. Response to touch shares similar properties with reactions to stresses such as wounding or pathogen attack, and regular mechanical stimulation leads to changes in growth and development called thigmomorphogenesis. Previous studies showed that well-known seismonastic plants such as Venus flytrap (Dionaea muscipula) or sensitive plant (Mimosa pudica) lost their touch-induced motive responses during exposure to general volatile anaesthetic (GVA) diethyl ether. Here, we investigated the effect of diethyl ether anaesthesia on touch response in Arabidopsis thaliana. We monitored [Ca 2+ ] cyt level, accumulation of JAs and expression of touch-responsive genes. Our results showed that none of the investigated responses was affected by diethyl ether. However, diethyl ether alone increased [Ca 2+ ] cyt and modulated JAs-independent touch-responsive genes, thus partially activating touch response non-specifically. Together with our previous studies, we concluded that GVA diethyl ether cannot block the local rise of [Ca 2+ ] cyt but only its systemic propagation dependent on GLUTAMATE LIKE RECEPTOR 3s (GLR3s) channels., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier GmbH. All rights reserved.)

Drought is a major abiotic stresses that severely hinder plant growth and agricultural productivity. The receptor-like kinase gene, ERECTA, has been proved to play important role in promoting the response to abiotic stress in crops. However, the specific molecular mechanisms underlying the drought resistance mediated by ERECTA in potato (Solanum tuberosum L.) are not well understood. In this study, sequence analysis confirmed that the StERECTA gene contains eight leucine-rich repeat (LRR) domains and an S_TKc domain, and these domains were highly conserved in Solanaceae family. Under drought stress, Arabidopsis thaliana strains overexpressing StERECTA showed increased biomass, proline (PRO) content, and antioxidant enzyme activities compared to the wild-type strains while the mutant ERECTA strain (er105) exhibited opposite phenotype. Additionally, StERECTA overexpression upregulated the expression of drought response marker genes (LEA3, DREB2A and P5CS1), improved levels of ABA and auxin, reduced stomatal density and relative expression level of stomatal development related genes (SPCH, FAMA and MUTE). Furthermore, Co-immunoprecipitation (Co-IP) assays demonstrated that StERECTA physically interacted with the YODA protein. In conclusion, our study provides new insights into the role and regulatory mechanism of StERECTA in response to drought stress. These findings may serve as a basis for genetic improvement of potato to enhance their tolerance to abiotic stress., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier GmbH. All rights reserved.)

Cold stress represents one of the major constraints for agricultural systems and crops productivity, inducing a wide range of negative effects. Particularly, long-term cold stress affects lipid metabolism, modifying the lipids/proteins ratio, the levels of phospholipids and glycolipids, and increasing lipids' unsaturation in bio-membranes. Glucose-6-phosphate dehydrogenase (G6PDH) reported prominent roles as NADPH suppliers in response to oxidative perturbations. Cytosolic G6PDH was suggested as the main isoform involved in cold stress response, while a down-regulation of the chloroplastic P1-G6PDH was observed. We thus investigated an Arabidopsis mutant defective for the P1-G6PDH (KO-P1) using integrated approaches to verify a possible role of this isoform in low temperature tolerance. KO-P1 genotype showed an improved tolerance to cold stress, highlighting a better photosynthetic efficiency, a reduction in stress markers content and a different regulation of genes involved in stress response. Intriguingly, the lack of P1-G6PDH induced modification in the levels of the main fatty acid and lipid species affecting the morphology of chloroplasts and mitochondria, which was restored under cold. Globally, these results indicate a priming effect induced by the absence of P1-G6PDH able to improve the tolerance to abiotic stress. Our results suggest novel and specific abilities of P1-G6PDH, highlighting its central role in different aspects of plant physiology and metabolism., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Gibberellic acids (GAs) are a group of endogenous phytohormones that play important roles in plant growth and development. SLENDER RICE (SLR) serves as a vital component of the DELLA gene family, which plays an irreplaceable role in regulating plant flowering and height, as well as stress responses. SLR gene has not been reported in mango, and its function is unknown. In present study, two DELLA subfamily genes MiSLR1 and MiSLR2 were identified from mango. MiSLR1 and MiSLR2 were highly expressed in the stems of the juvenile stage, but were expressed at a low level in flower buds and flowers. Gibberellin treatment could up-regulate the expression of MiSLR1 and MiSLR2 genes, but gibberellin biosynthesis inhibitor prohexadione-calcium (Pro-Ca) and paclobutrazol (PAC) treatments significantly down-regulated the expression of MiSLR1, while MiSLR2 was up-regulated. The expression levels of MiSLR1 and MiSLR2 were up-regulated under both salt and drought treatments. Overexpression of MiSLR1 and MiSLR2 genes significantly resulted early flowering in transgenic Arabidopsis and significantly up-regulated the expression levels of endogenous flower-related genes, such as SUPPRESSOR OF CONSTANS1 (SOC1), APETALA1 (AP1), and FRUITFULL (FUL). Interestingly, MiSLR1 significantly reduced the height of transgenic plants, while MiSLR2 gene increased. Overexpression of MiSLR1 and MiSLR2 increased seed germination rate, root length and survival rate of transgenic plants under salt and drought stress. Physiological and biochemical detection showed that the contents of proline (Pro) and superoxide dismutase (SOD) were significantly increased, while the contents of malondialdehyde (MDA) and H 2 O 2 were significantly decreased. Additionally, protein interaction analysis revealed that MiSLR1 and MiSLR2 interacted with several flowering-related and GA-related proteins. The interaction between MiSLR with MiGF14 and MiSOC1 proteins was found for the first time. Taken together, the data showed that MiSLR1 and MiSLR2 in transgenic Arabidopsis both regulated the flowering time and plant height, while also acting as positive regulators of abiotic stress responses., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Chromatin structure and dynamics regulate all DNA-templated processes, such as transcription, replication, and repair. Chromatin binding factors, chromatin architectural proteins, and nucleosome remodelers modulate chromatin structure and dynamics and, thereby, the various DNA-dependent processes. Arabidopsis thaliana DEK3, a member of the evolutionarily conserved DEK domain-containing chromatin architectural proteins, is an important factor for chromatin structure and function, involved in transcriptional programming to regulate flowering time and abiotic stress tolerance. AtDEK3 contains an uncharacterized N-terminal domain, a middle SAF domain (winged helix-like domain), and a C-terminal DEK domain, but their role in the interaction of AtDEK3 with histones and DNA remained poorly understood. Using biochemical and biophysical analyses, we provide a comprehensive in vitro characterization of the different AtDEK3 domains for their interaction with histone H3/H4 and DNA. AtDEK3 directly interacts with histone H3/H4 tetramers through its N-terminal domain and the C-terminal DEK domain in a 1:1 stoichiometry. Upon interaction with H3/H4, the unstructured N-terminal domain of AtDEK3 undergoes a conformational change and adopts an alpha-helical conformation. In addition, the in-solution envelope structures of the AtDEK3 domains and their complex with H3/H4 have been characterized. The SAF and DEK domains associate with double-stranded and four-way junction DNA. As DEK3 possesses a histone-interacting domain at the N- and the C-terminus and a DNA-binding domain in the middle and at the C-terminus, the protein might play a complex role as a chromatin remodeler., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.)

Caffeoyl-coenzyme 3 A-O-methyltransferase (CCoAOMT) plays a crucial role in the lignin synthesis in many higher plants. In this study, nine PbCCoAOMT genes in total were identified from pear, and classified into six categories. We treated pear fruits with hormones abscisic acid (ABA) and methyl jasmonate (MeJA) and salicylic acid (SA) and observed differential expression levels of these genes. Through qRT-PCR, we also preliminarily identified candidate PbCCoAOMT gene, potentially involved in lignin synthesis in pear fruits. Additionally, the overexpression of PbCCoAOMT1/2 in Arabidopsis and pear fruits increased in lignin content. Enzymatic assays showed that recombinant PbCCoAOMT1/2 proteins have similar enzymatic activity in vitro. The Y1H (Yeast one-hybrid) and dual luciferase (dual-LUC) experiments demonstrated that PbMYB25 can bind to the AC elements in the promoter region of the PbCCoAOMT1 gene. Our findings suggested that the PbCCoAOMT1 and PbCCoAOMT2 genes may contribute to the synthesis of lignin and provide insights into the mechanism of lignin biosynthesis and stone cell development in pear fruits., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Key Message: Overexpression of HvbHLH132 from hulless barley impairs in chilling and freezing tolerance at the seedlings stage in Arabidopsis thaliana The basic helix-loop-helix (bHLH) transcription factors (TF) are ubiquitously existed in eukaryote and play crucial roles in numerous biological processes. However, the characterization of their members and functions in hulless barley remains limited. Here, we conducted a genome-wide identification of the HvbHLH gene family and assessed the role of HvbHLH132 in cold stress tolerance. We identified 141 HvbHLH genes, which were categorized into twelve subfamilies. Subcellular localization predictions indicated that the majority of HvbHLH proteins were localized in the nucleus. cis-Acting element analysis revealed that the promoter regions of the HvbHLH family contain diverse elements associated with various biological processes. Expression profiling of the 141 HvbHLH genes in two extreme varieties revealed that HvbHLH132 was significantly induced and exhibited substantial differential expression under cold stress. Analyses of subcellular localization and transactivation activity confirmed that HvbHLH132 specifically localized in the nucleus and contributed to transcriptional activation. Furthermore, overexpression of HvbHLH132 in Arabidopsis resulted in impaired chilling and freezing tolerance at the seedling stage, leading to biochemical changes unfavorable for freezing stress. Additionally, the expression of some cold-responsive genes (COR) genes was significantly less induced compared to wild type under freezing stress. This study provides comprehensive insight into the HvbHLH gene family and reveals a critical role of HvbHLH132 in regulating cold tolerance in plants., Competing Interests: Declarations. Conflict of interest: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Key Message: Constitutive expression of cucumber CsACS2 in Arabidopsis disrupts anther dehiscence and male fertility via ethylene signaling and DNA methylation, revealing new avenues for enhancing crop reproductive traits. The cucumber gene CsACS2, encoding ACC (1-aminocyclopropane-1-carboxylic acid) synthase, plays a pivotal role in ethylene biosynthesis and sex determination. This study investigates the effects of constitutive CsACS2 expression in Arabidopsis thaliana on anther development and male fertility. Transgenic Arabidopsis plants overexpressing CsACS2 exhibited male sterility due to inhibited anther dehiscence, which was linked to suppressed secondary cell wall thickening. RNA-Seq analysis revealed upregulation of ethylene signaling pathway genes and downregulation of secondary cell wall biosynthesis genes, with gene set enrichment analysis indicating the involvement of DNA methylation. Rescue experiments demonstrated that silver nitrate (AgNO₃) effectively restored fertility, while 5-azacytidine (5-az) partially restored it, highlighting the roles of ethylene signaling and DNA methylation in this process. Constitutive CsACS2 expression in Arabidopsis disrupts anther development through ethylene signaling and DNA methylation pathways, providing new insights into the role of ethylene in plant reproductive development and potential applications in crop improvement., Competing Interests: Declarations. Conflict of interests: The authors state that they have no known financial conflicts of interest or personal relationships that may have influenced the research presented in this paper., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The role of molecular hydrogen (H 2 ) in autophagy during inflammatory response is controversial in mammalian cells. Although the stimulation of H 2 production in response to osmotic stress was observed in plants, its synthetic pathway and the interrelationship between its induction and plant autophagy remain unclear. Here, the induction of autophagy was observed in Arabidopsis upon osmotic stress, assessing by the autophagosome formation and autophagy-related genes expression. Above responses were intensified by H 2 fumigation. Meanwhile, the reduction in seedling growth and roots vigor was obviously abolished, accompanied by reestablishing redox balance. These H 2 responses were markedly impaired in T-DNA knockout lines atg2, atg5, and atg18. Further evidence showed that the increased endogenous H 2 synthesis by genetic manipulation, not only stimulated autophagosome formation, but also triggered various plant responses toward osmotic stress. By contrast, these responses were obviously abolished by the disruption of endogenous H 2 synthesis with the addition of 2,6-dichloroindophenol sodium salt. Together, the integrated genetic and molecular evidence clearly illustrated the requirement of autophagy activation in H 2 control of plant osmotic tolerance., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Tea plants (Camellia sinensis L.) are prone to spring frosts, leading to substantial economic damage. WRKY transcription factors are key in plant abiotic stress responses, yet the role of CsWRKY29 in freezing tolerance is unclear. In this study, quantitative real-time PCR (qRT-PCR) and transient green fluorescent protein assay revealed that CsWRKY29 localizes to the nucleus and its expression is induced by cold and abscisic acid (ABA). CsWRKY29 overexpression in Arabidopsis enhanced freezing tolerance, reduced electrolyte leakage, increased soluble sugars, and boosted superoxide dismutase activity, with upregulated COR genes. These lines also showed heightened ABA and glucose sensitivity. Cold treatment of CsWRKY29-overexpressing lines upregulated AtABI5, AtHXK1, and AtSUS4 compared to wild type, and yeast one-hybrid assays confirmed CsWRKY29 binding to the W-box in the CsABI5 promoter. Furthermore, the application of virus-induced gene silencing (VIGS) technology to reduce CsWRKY29 expression in tea plants revealed a significant decrease in the transcript levels of CsCBFs, CsABI5, CsHXK1, and CsSUS4 in the silenced plants. In summary, our findings indicate that CsWRKY29 may serve as a critical transcription factor that contributes to freezing tolerance, ABA responsiveness, and sugar metabolism within tea plants., Competing Interests: Declarations Competing interests The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. Ethical approval and consent to participate We do not contain any studies with human or animal subjects. Consent for publication Our manuscript doesn’t contain any individual person’s data in any form (including any individual details, images or videos)., (© 2024. The Author(s).)

Plasmodiophora brassicae, the causative agent of clubroot disease, establishes a long-lasting parasitic relationship with its host by inducing the expression of sugar transporters. Previous studies have indicated that most BrSWEET genes in Chinese cabbage are up-regulated upon infection with P. brassicae. However, the key BrSWEET genes responsive to P. brassicae have not been definitively identified. In this study, we selected five BrSWEET genes and conducted a functional analysis of them. These five BrSWEET genes showed a notable up-regulation in roots after P. brassicae inoculation. Furthermore, these BrSWEET proteins were localized to the plasma membrane. Yeast functional complementation assays confirmed transport activity for glucose, fructose, or sucrose in four BrSWEETs, with the exception of BrSWEET2a. Mutants and silenced plants of BrSWEET1a, -11a, and -12a showed lower clubroot disease severity compared to wild-type plants, while gain-of-function Arabidopsis thaliana plants overexpressing these three BrSWEET genes exhibited significantly higher disease incidence and severity. Our findings suggested that BrSWEET1a, BrSWEET11a, and BrSWEET12a play pivotal roles in P. brassicae-induced gall formation, shedding light on the role of sugar transporters in host-pathogen interactions., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Aeonium arboreum 'Halloween', a popular indoor ornamental succulent in China, changes its leaf colour to red on light exposure. However, the underlying molecular mechanisms is still vague. Comparative analysis of transcriptome data from 'Halloween' leaves treated under dark and light conditions revealed two R2R3-MYB transcription factors, AaMYB113 and AaMYB114, that may mediate anthocyanin accumulation. In this study, we cloned the AaMYB113 and AaMYB114 genes, encoding proteins of 279 and 248 amino acids, respectively. Transcriptional activity analysis revealed that AaMYB113 exhibits strong transcriptional activity, in contrast to AaMYB114, which demonstrates minimal activity. Transient expression studies in tobacco leaves demonstrated that AaMYB113 induced red pigmentation, whereas AaMYB114 did not. Subsequent stable overexpression in Arabidopsis thaliana confirmed that AaMYB113, but not AaMYB114, could similarly turn Arabidopsis leaves red. Further stable transformation of AaMYB113 in tobacco affected multiple floral components, including leaves, petals, calyx, flower tubes, and filaments, turning them red. Quantitative real-time PCR (qRT-PCR) assay in leaves of AaMYB113 stably transformed tobacco and Arabidopsis revealed upregulation of anthocyanin biosynthesis-related structural genes and TT8-like transcription factors. Moreover, the dual luciferase analysis confirmed that AaMYB113 can activate the promoters of 'Halloween' anthocyanin synthesis structural genes, AaCHS, AaCHI, AaF3H, AaDFR and AaANS. The above results indicate that AaMYB113 can promote anthocyanin synthesis, while AaMYB114 does not have this function. This study contributes significantly to the limited body of research on the molecular mechanisms of anthocyanin synthesis in succulents, advancing our understanding of how these pathways are regulated in 'Halloween' succulents and potentially other species., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

We examined whether plant-type phosphoenolpyruvate carboxylase (PEPC) is involved in flower organ formation or not by over-expression in Arabidopsis. A wheat PEPC isogene Tappc3A, belonging to the ppc3 group, was targeted due to its preferential expression pattern in pistils and stamens. Transgenic Arabidopsis over-expressing Tappc3A exhibited irregular stamen formation, i.e., a lesser number of stamens per flower and shorter filaments in T 2 and T 3 generations. Irregular stamens were frequently observed in homozygous T 4 lines, but no morphological change was observed in other floral organs. High-degree gene co-expression of Tappc3 isogenes with wheat SEEDSTICKs but not with other homeotic transcription factor genes for flower formation implicates that Tappc3 is under control by the class D genes of the ABCDE model to flower development. In addition, the conservation of CArG box sequences on the Tappc3 promoters supported the developmentally programmed gene expression of ppc3 in wheat flowering organs. Thus, this study provides the first experimental evidence for the critical regulation of plant-type PEPC for flower formation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)