Wall Modification Research Articles

Genomic convergence underlying high-altitude adaptation in alpine plants.

Evolutionary convergence is one of the most striking examples of adaptation driven by natural selection. However, genomic evidence for convergent adaptation to extreme environments remains scarce. Here, we assembled reference genomes of two alpine plants, Saussurea obvallata (Asteraceae) and Rheum alexandrae (Polygonaceae), with 37,938 and 61,463 annotated protein-coding genes. By integrating an additional five alpine genomes, we elucidated genomic convergence underlying high-altitude adaptation in alpine plants. Our results detected convergent contractions of disease-resistance genes in alpine genomes, which might be an energy-saving strategy for surviving in hostile environments with only a few pathogens present. We identified signatures of positive selection on a set of genes involved in reproduction and respiration (e.g., MMD1, NBS1, and HPR), and revealed signatures of molecular convergence on genes involved in self-incompatibility, cell wall modification, DNA repair and stress resistance, which may underlie adaptation to extreme cold, high ultraviolet radiation and hypoxia environments. Incorporating transcriptomic data, we further demonstrated that genes associated with cuticular wax and flavonoid biosynthetic pathways exhibit higher expression levels in leafy bracts, shedding light on the genetic mechanisms of the adaptive "greenhouse" morphology. Our integrative data provide novel insights into convergent evolution at a high-taxonomic level, aiding in a deep understanding of genetic adaptation to complex environments.

Identification of d-arabinan-degrading enzymes in mycobacteria

Bacterial cell growth and division require the coordinated action of enzymes that synthesize and degrade cell wall polymers. Here, we identify enzymes that cleave the d-arabinan core of arabinogalactan, an unusual component of the cell wall of Mycobacterium tuberculosis and other mycobacteria. We screened 14 human gut-derived Bacteroidetes for arabinogalactan-degrading activities and identified four families of glycoside hydrolases with activity against the d-arabinan or d-galactan components of arabinogalactan. Using one of these isolates with exo-d-galactofuranosidase activity, we generated enriched d-arabinan and used it to identify a strain of Dysgonomonas gadei as a d-arabinan degrader. This enabled the discovery of endo- and exo-acting enzymes that cleave d-arabinan, including members of the DUF2961 family (GH172) and a family of glycoside hydrolases (DUF4185/GH183) that display endo-d-arabinofuranase activity and are conserved in mycobacteria and other microbes. Mycobacterial genomes encode two conserved endo-d-arabinanases with different preferences for the d-arabinan-containing cell wall components arabinogalactan and lipoarabinomannan, suggesting they are important for cell wall modification and/or degradation. The discovery of these enzymes will support future studies into the structure and function of the mycobacterial cell wall.

Platypnea-Orthodeoxia Syndrome Manifesting as an Early Complication after Lower Bilobectomy

Platypnea-orthodeoxia syndrome (POS) is an uncommon clinical condition characterized by orthostatic dyspnea and hypoxemia. The case of a female patient who manifested postoperative episodes of sudden oxygen desaturation, dyspnea, and systemic arterial hypotension following lower bilobectomy for lung adenocarcinoma was reported. After meticulous clinical investigations, the patient proved to be affected by a rare form of postural dyspnea: platypnea-orthodeoxia syndrome, a clinical disorder described in the middle of the last century. The pathophysiology was found in an intracardiac mechanism of right-to-left blood shunt, combined with lung and chest wall modification. Atrial septal defect, such as patent foramen ovale (PFO), is a common cause of platypnea-orthodeoxia syndrome; the rescue closure of PFO usually allows for an immediate and consistent improvement of the symptoms.

Modification Mechanisms and Properties of Poplar Wood via Grafting with 2-Hydroxyethyl Methacrylate/N,N'-methylenebis(acrylamide) onto Cell Walls.

As the only renewable resource among the four basic materials (steel, cement, plastic, wood), wood itself and wood products have a "low carbon" value and play an important role in storing carbon. The moisture absorption and expansion properties of wood limit its application scope and shorten its service life. To enhance the mechanical and physical properties of fast-growing poplars, an eco-friendly modification procedure has been used. This was accomplished by the in situ modification of wood cell walls by vacuum pressure impregnation with a reaction of water-soluble 2-hydroxyethyl methacrylate (HEMA) and N,N'-methylenebis(acrylamide) (MBA). The anti-swelling efficiency of HEMA/MBA-treated wood was improved (up to 61.13%), whereas HEMA/MBA-treated wood presented a lower weight-gain rate (WG) and water-absorption rate (WAR). It was observed that the modulus of elasticity, hardness, density, and other properties of modified wood had improved significantly, as indicated by XRD analysis. Modifiers diffuse primarily within cell walls and cell interstices of wood, causing crosslinks between the modifiers and the cell walls, reducing its hydroxyl content and blocking the channels for water movement, thereby enhancing its physical properties. This result can be obtained by scanning electron microscopy (SEM) and energy dispersive x-ray spectroscopy (EDX), Nitrogen adsorption test imaging ATR-FTIR (Attenuated total reflection-Fourier-Transform Infrared) Spectroscopy, and nuclear magnetic resonance (NMR) and Nitrogen adsorption test. Overall, this straightforward, high-performance modification method is crucial for maximizing wood's efficiency and the sustainable development of human society.

Molecular mechanism of saline-alkali stress tolerance in the green manure crop Sophora alopecuroides

Selecting suitable plants as green manures is essential for improving marginal soil fertility and sustainable agroecosystems. Sophora alopecuroides is a highly salt- and alkali-tolerant leguminous plant that is often used as green manure. However, the molecular mechanism underlying saline-alkali tolerance in S. alopecuroides remains largely unclear. In this study, we investigated the molecular mechanisms underlying saline-alkali stress tolerance through physiological and transcriptomic analyses in S. alopecuroides seedlings. Comparative transcriptome analysis revealed that saline-alkali stress induced the expression of genes involved in cell wall modification, thereby increasing the contents of pectin and hemicellulose in roots and improving saline-alkali stress tolerance. The expression of genes related to the glycolysis pathway was induced, whereas genes involved in the TCA cycle and primary nitrogen metabolism were downregulated under salt and alkali stresses, indicating that S. alopecuroides plants modulate carbon flow to provide energy and ultimately regulate saline-alkali stress adaptation. Saline-alkali stress also modulated phytohormone signaling pathways in S. alopecuroides. Moreover, the leaves of seedlings under salt and alkali stresses contained elevated potassium, zinc and manganese contents, and the roots of seedlings under salt stress contained higher iron content. Taken together, these adaptive mechanisms to saline-alkali stress provide a physiological basis for the coordinated nutrient cycling of S. alopecuroides green manure. These results provide a molecular basis for the phytoremediation and utilization of saline-alkali soil, enabling the design of an integrated nutrient cycling system and optimization of the cultivation and field management of S. alopecuroides green manure.

Heterologous overexpression of Apocynum venetum flavonoids synthetase genes improves Arabidopsis thaliana salt tolerance by activating the IAA and JA biosynthesis pathways.

Salt stress is a serious abiotic stress that primarily inhibits plant growth, resulting in severe yield losses. Our previous research found that flavonoids play important roles in A. venetum salt stress tolerance. In response to salt stress, we noted that the flavonoid content was depleted in A. venetum. However, the detailed mechanism is still not clear. In this study, the expression patterns of three flavonoids synthetase genes, AvF3H, AvF3'H, and AvFLS were systemically analyzed under salt stress in A. venetum seedlings. The salt tolerance of transgenic Arabidopsis plants was improved by heterologous overexpression of these synthetase genes. The NBT and DAB staining results as well as H2O2 and O2•- content analysis revealed that under salt stress, ROS molecules were reduced in transgenic plants compared to WT plants, which corresponded to the activation of the antioxidant enzyme system and an increase in total flavonoid content, particularly rutin, eriodictyol, and naringerin in transgenic plants. External application of flavonoids reduced ROS damage in WT plants just like what we observed in the transgenic plants (without the external application). Additionally, our transcriptome analysis demonstrated that auxin and jasmonic acid biosynthesis genes, as well as signaling transduction genes, were primarily activated in transgenic plants under salt stress, leading to activation of the cell wall biosynthesis or modification genes that promote plant growth. As a result, we investigated the mechanism through flavonoids enhance the salt tolerance, offering a theoretical foundation for enhancing salt tolerance in plants.

Synthesis of Pore‐Wall‐Modified Stable COF/TiO2 Heterostructures via Site‐Specific Nucleation for an Enhanced Photoreduction of Carbon Dioxide

Constructing stable heterostructures with appropriate active site architectures in covalent organic frameworks (COFs) can improve the active site accessibility and facilitate charge transfer, thereby increasing the catalytic efficiency. Herein, a pore-wall modification strategy is proposed to achieve regularly arranged TiO2 nanodots (≈1.82 nm) in the pores of COFs via site-specific nucleation. The site-specific nucleation strategy stabilizes the TiO2 nanodots as well as enables the controlled growth of TiO2 throughout the COFs' matrix. In a typical process, the pore wall is modified and site-specific nucleation is induced between the metal precursors and the organic walls of the COFs through a careful ligand selection, and the strongly bonded metal precursors drive the confined growth of ultrasmall TiO2 nanodots during the subsequent hydrolysis. This will result in remarkably improved surface reactions, owing to the superior catalytic activity of TiO2 nanodots functionalized to COFs through strong NTiO bonds. Furthermore, density functional theory studies reveal that pore-wall modification is beneficial for inducing strong interactions between the COF and TiO2 and results in a large energy transfer via the NTiO bonds. This work highlights the feasibility of developing stable COF and metal oxide based heterostructures via organic wall modifications to produce carbon fuels by artificial photosynthesis.

The transcriptional mechanism responding to air particulate matter in Laurus nobilis (L.)

Air levels of particulate matter (PM) are dangerously increasing in urban environment due to high levels of industrialization. The use of plants to reduce pollutants is well-known although molecular mechanisms underlying this phenomenon have been scarcely investigated. The aim of this work was to shed lights into the molecular physiological responses of leaves of a typical plant ornamental species (Laurus nobilis L.), to identify key PM-modulated genes of early leaf responses and to optimize phylloremediation strategies in polluted areas. The transcriptome and the PM accumulation in leaf tissues were analysed in plants grown in pots for three months under two different areas: rural and traffic. Differentially expressed genes in common between different pairwise comparisons were highly effective in discriminating leaves at high PM levels after three months of exposure. Thirty of these genes showed contrasting trend of expression between rural and traffic conditions. Higher PM levels highlighted significant repression of genes and gene set categories involved in cell wall and membrane modification. In addition, a repression of genes involved in photosynthesis reactions, glycolysis, gluconeogenesis, TCA, fermentation was observed. Some key members of C2H2, WRKYs and CCAAT-HAP2 were induced as well as downstream defense response genes. The results allowed to develop a general model of gene regulatory networks in response to particulate matter in plants and innovative biotechnological approaches for phylloremediation strategies.

Rare earth elements detoxification mechanism in the hyperaccumulator Dicranopteris linearis: [silicon-pectin] matrix fixation

Dicranopteris linearis is the best-known hyperaccumulator species of rare earth elements (REEs) and silicon (Si), capable of dealing with toxic level of REEs. Hence, this study aimed to clarify how D. linearis leaves cope with excessive REE stress, and whether Si plays a role in REE detoxification. The results show that lanthanum (La – as a representative of the REEs) stress led to decreased biomass and an increase of metabolism related to leaf cell wall synthesis and modification. However, the La stress-induced responses, especially the increase of pectin-related gene expression level, pectin polysaccharides concentration, and methylesterase activity, could be mitigated by Si supply. Approximately 70% of the Si in D. linearis leaves interacted with the cell walls to form organosilicon Si-O-C linkages. The Si-modified cell walls contained more hydroxyl groups, leading to a more efficient REE retention compared to the Si-free ones. Moreover, this [Si-cell wall] matrix increased the pectin-La accumulation capacity by 64%, with no effect on hemicellulose-La and cellulose-La accumulation capacity. These results suggest that [Si-pectin] matrix fixation is key in REE detoxification in D. linearis, laying the foundation for the development of phytotechnological applications (e.g., REE phytomining) using this species in REE-contaminated sites.

Morpho-anatomical characterization, gene expression and protein cell wall modifications associated with natural finger drop in bananas

Banana (Musa spp.) is one of the main fruits consumed worldwide. However, finger drop, is a physiological disorder that causes many postharvest problems, which eventually reduces market value and consumer acceptance. Therefore, the objective of the study was to evaluate the anatomical changes that occur in the pedicel rupture area (drop zone) of bananas diploids (BB França) and tetraploid (BRS Pioneira) in three ripening stages. The levels of gene expression involved in the natural ripening process and in the development of finger drop, was also investigated. The accumulation of their mRNAs and those of expansin (EXP1), pectate lyase (PEL1) and xyloglucan endotransglucosylase/hydrolase protein (XTH4) genes already isolated from bananas were measured by quantitative polymerase chain reaction in three ripening stages. BB França presented a higher resistance to finger drop due to the presence of some specific morphoanatomical characteristics, such as larger parenchymal cells and greater deposition of lignin. In contrast, there was degeneration of the pedicel parenchymal tissue of the BRS Pioneira genotype, forming large empty spaces during the ripening of the fruits, mainly in stage 6, which contributed to the finger drop. The diploid BB França is a strong candidate for use in banana breeding programs aimed at fruit drop resistance. This will certainly improve the quality of banana varieties. Moreover, PEL1 proved to be an excellent candidate gene for functional studies of finger drop in bananas.

Mechanical Stimulation Decreases Auxin and Gibberellic Acid Synthesis but Does Not Affect Auxin Transport in Axillary Buds; It Also Stimulates Peroxidase Activity in Petunia × atkinsiana

Thigmomorphogenesis (or mechanical stimulation-MS) is a term created by Jaffe and means plant response to natural stimuli such as the blow of the wind, strong rain, or touch, resulting in a decrease in length and an increase of branching as well as an increase in the activity of axillary buds. MS is very well known in plant morphology, but physiological processes controlling plant growth are not well discovered yet. In the current study, we tried to find an answer to the question if MS truly may affect auxin synthesis or transport in the early stage of plant growth, and which physiological factors may be responsible for growth arrest in petunia. According to the results of current research, we noticed that MS affects plant growth but does not block auxin transport from the apical bud. MS arrests IAA and GA3 synthesis in MS-treated plants over the longer term. The main factor responsible for the thickening of cell walls and the same strengthening of vascular tissues and growth arrestment, in this case, is peroxidase (POX) activity, but special attention should be also paid to AGPs as signaling molecules which also are directly involved in growth regulation as well as in cell wall modifications.

Transcriptomic Analysis Reveals Panicle Heterosis in an Elite Hybrid Rice ZZY10 and Its Parental Lines.

Heterosis is the phenomenon in which some hybrid traits are superior to those of their parents. Most studies have analyzed the heterosis of agronomic traits of crops; however, heterosis of the panicles can improve yield and is important for crop breeding. Therefore, a systematic study of panicle heterosis is needed, especially during the reproductive stage. RNA sequencing (RNA Seq) and transcriptome analysis are suitable for further study of heterosis. Using the Illumina Nova Seq platform, the transcriptome of ZhongZheYou 10 (ZZY10), an elite rice hybrid, the maintainer line ZhongZhe B (ZZB), and the restorer line Z7-10 were analyzed at the heading date in Hangzhou, 2022. 581 million high-quality short reads were obtained by sequencing and were aligned against the Nipponbare reference genome. A total of 9000 differential expression genes were found between the hybrids and their parents (DGHP). Of the DGHP, 60.71% were up-regulated and 39.29% were down-regulated in the hybrid. Comparative transcriptome analysis revealed that 5235 and 3765 DGHP were between ZZY10 and ZhongZhe B and between ZZY10 and Z7-10, respectively. This result is consistent with the transcriptome profile of ZZY10 and was similar to Z7-10. The expression patterns of DGHP mainly exhibited over-dominance, under-dominance, and additivity. Among the DGHP-involved GO terms, pathways such as photosynthesis, DNA integration, cell wall modification, thylakoid, and photosystem were significant. 21 DGHP, which were involved in photosynthesis, and 17 random DGHP were selected for qRT-PCR validation. The up-regulated PsbQ and down-regulated subunits of PSI and PSII and photosynthetic electron transport in the photosynthesis pathway were observed in our study. Extensive transcriptome data were obtained by RNA-Seq, providing a comprehensive overview of panicle transcriptomes at the heading stage in a heterotic hybrid.

The regulation of plant cell wall organisation under salt stress.

Plant cell wall biosynthesis is a complex and tightly regulated process. The composition and the structure of the cell wall should have a certain level of plasticity to ensure dynamic changes upon encountering environmental stresses or to fulfil the demand of the rapidly growing cells. The status of the cell wall is constantly monitored to facilitate optimal growth through the activation of appropriate stress response mechanisms. Salt stress can severely damage plant cell walls and disrupt the normal growth and development of plants, greatly reducing productivity and yield. Plants respond to salt stress and cope with the resulting damage by altering the synthesis and deposition of the main cell wall components to prevent water loss and decrease the transport of surplus ions into the plant. Such cell wall modifications affect biosynthesis and deposition of the main cell wall components: cellulose, pectins, hemicelluloses, lignin, and suberin. In this review, we highlight the roles of cell wall components in salt stress tolerance and the regulatory mechanisms underlying their maintenance under salt stress conditions.

Genome and Transcriptome Identification of a Rice Germplasm with High Cadmium Uptake and Translocation.

The safe production of food on Cd-polluted land is an urgent problem to be solved in South China. Phytoremediation or cultivation of rice varieties with low Cd are the main strategies to solve this problem. Therefore, it is very important to clarify the regulatory mechanism of Cd accumulation in rice. Here, we identified a rice variety with an unknown genetic background, YSD, with high Cd accumulation in its roots and shoots. The Cd content in the grains and stalks were 4.1 and 2.8 times that of a commonly used japonica rice variety, ZH11, respectively. The Cd accumulation in the shoots and roots of YSD at the seedling stage was higher than that of ZH11, depending on sampling time, and the long-distance transport of Cd in the xylem sap was high. Subcellular component analysis showed that the shoots, the cell wall, organelles, and soluble fractions of YSD, showed higher Cd accumulation than ZH11, while in the roots, only the cell wall pectin showed higher Cd accumulation. Genome-wide resequencing revealed mutations in 22 genes involved in cell wall modification, synthesis, and metabolic pathways. Transcriptome analysis in Cd-treated plants showed that the expression of pectin methylesterase genes was up-regulated and the expression of pectin methylesterase inhibitor genes was down-regulated in YSD roots, but there were no significant changes in the genes related to Cd uptake, translocation, or vacuole sequestration. The yield and tiller number per plant did not differ significantly between YSD and ZH11, but the dry weight and plant height of YSD were significantly higher than that of ZH11. YSD provides an excellent germplasm for the exploration of Cd accumulation genes, and the cell wall modification genes with sequence- and expression-level variations provide potential targets for phytoremediation.

Molecular mechanisms involved in fruit cracking: A review.

Several fleshy fruits are highly affected by cracking, a severe physiological disorder that compromises their quality and causes high economical losses to the producers. Cracking can occur due to physiological, genetic or environmental factors and may happen during fruit growth, development and ripening. Moreover, in fleshy fruits, exocarp plays an important role, acting as a mechanical protective barrier, defending against biotic or abiotic factors. Thus, when biochemical properties of the cuticle + epidermis + hypodermis are affected, cracks appear in the fruit skin. The identification of genes involved in development such as cell wall modifications, biosynthesis and transport of cuticular waxes, cuticular membrane deposition and associated transcription factors provides new insights to better understand how fruit cracking is affected by genetic factors. Amongst the major environmental stresses causing cracking are excessive water during fruit development, leading to imbalances in cations such as Ca. This review focus on expression of key genes in these pathways, in their influence in affected fruits and the potential for molecular breeding programs, aiming to develop cultivars more resistant to cracking under adverse environmental conditions.

Cross‐disciplinary insights into the mechanisms of plant cold hardiness: From molecules to ecosystems

Cross‐disciplinary insights into the mechanisms of plant cold hardiness: From molecules to ecosystems

Transcript profiling of olive fruit tissues in late development reveals complex vesicle trafficking and hormonal regulation involved in cell wall modifications

Transcript profiling of olive fruit tissues in late development reveals complex vesicle trafficking and hormonal regulation involved in cell wall modifications

Comparative transcriptome analysis in peaberry and regular bean coffee to identify bean quality associated genes

BackgroundThe peaberry bean in Arabica coffee has exceptional quality compared to the regular coffee bean. Understanding the molecular mechanism of bean quality is imperative to introduce superior coffee quality traits. Despite high economic importance, the regulatory aspects of bean quality are yet largely unknown in peaberry. A transcriptome analysis was performed by using peaberry and regular coffee beans in this study.ResultsThe result of phenotypic analysis stated a difference in the physical attributes of both coffee beans. In addition, transcriptome analysis revealed low genetic differences. Only 139 differentially expressed genes were detected in which 54 genes exhibited up-regulation and 85 showed down-regulations in peaberry beans compared to regular beans. The majority of differentially expressed genes had functional annotation with cell wall modification, lipid binding, protein binding, oxidoreductase activity, and transmembrane transportation. Many fold lower expression of Ca25840-PMEs1, Ca30827-PMEs2, Ca30828-PMEs3, Ca25839-PMEs4, Ca36469-PGs. and Ca03656-Csl genes annotated with cell wall modification might play a critical role to develop different bean shape patterns in Arabica. The ERECTA family genes Ca15802-ERL1, Ca99619-ERL2, Ca07439-ERL3, Ca97226-ERL4, Ca89747-ERL5, Ca07056-ERL6, Ca01141-ERL7, and Ca32419-ERL8 along lipid metabolic pathway genes Ca06708-ACOX1, Ca29177-ACOX2, Ca01563-ACOX3, Ca34321-CPFA1, and Ca36201-CPFA2 are predicted to regulate different shaped bean development. In addition, flavonoid biosynthesis correlated genes Ca03809-F3H, Ca95013-CYP75A1, and Ca42029-CYP75A2 probably help to generate rarely formed peaberry beans.ConclusionOur results provide molecular insights into the formation of peaberry. The data resources will be important to identify candidate genes correlated with the different bean shape patterns in Arabica.

Identification and Characterization of Long Non-Coding RNAs: Implicating Insights into Their Regulatory Role in Kiwifruit Ripening and Softening during Low-Temperature Storage.

Long non-coding RNAs (lncRNAs) are crucial players regulating many biological processes in plants. However, limited knowledge is available regarding their roles in kiwifruit ripening and softening. In this study, using lncRNA-seq technology, 591 differentially expressed (DE) lncRNAs (DELs) and 3107 DE genes (DEGs) were identified from kiwifruit stored at 4 °C for 1, 2, and 3 weeks in comparison with non-treated control fruits. Of note, 645 DEGs were predicted to be targets of DELs (DEGTLs), including some DE protein-coding genes (such as β-amylase and pectinesterase). DEGTL-based GO enrichment analysis revealed that these genes were significantly enriched in cell wall modification and pectinesterase activity in 1 W vs. CK and 3 W vs. CK, which might be closely related to the fruit softening during low-temperature storage. Moreover, KEGG enrichment analysis revealed that DEGTLs were significantly associated with starch and sucrose metabolism. Our study revealed that lncRNAs play critical regulatory roles in kiwifruit ripening and softening under low-temperature storage, mainly by mediating the expression of starch and sucrose metabolism and cell wall modification related genes.

Changes in the morphology traits, anatomical structure of the leaves and transcriptome in Lycium barbarum L. under salt stress.

Salt stress directly affects the growth of plants. The limitation of leaf grow is among the earliest visible effects of salt stress. However, the regulation mechanism of salt treatments on leaf shape has not been fully elucidated. We measured the morphological traits and anatomical structure. In combination with transcriptome analysis, we analyzed differentially expressed genes (DEGs) and verified the RNA-seq data by qRT-PCR. Finally, we analyzed correlation between leaf microstructure parameters and expansin genes. We show that the leaf thickness, the width, and the leaf length significantly increased at elevated salt concentrations after salt stress for 7 days. Low salt mainly promoted the increase in leaves length and width, but high salt concentration accelerated the leaf thickness. The anatomical structure results indicated that palisade mesophyll tissues contribute more to leaf thickness than spongy mesophyll tissues, which possibly contributed to the increase in leaf expansion and thickness. Moreover, a total of 3,572 DEGs were identified by RNA-seq. Notably, six of the DEGs among 92 identified genes concentrated on cell wall synthesis or modification were involved in cell wall loosening proteins. More importantly, we demonstrated that there was a strong positive correlation between the upregulated EXLA2 gene and the thickness of the palisade tissue in L. barbarum leaves. These results suggested that salt stress possibly induced the expression of EXLA2 gene, which in turn increased the thickness of L. barbarum leaves by promoting the longitudinal expansion of cells of the palisade tissue. This study lays a solid knowledge for revealing the underlying molecular mechanisms of leaf thickening in L. barbarum in response to salt stresses.