Root Profile Research Articles

Exploring the response of yellow lupine (Lupinus luteus L.) root to drought mediated by pathways related to phytohormones, lipid, and redox homeostasis.

Yellow lupine (Lupinus luteus L.) is a high-protein crop of considerable economic and ecological significance. It has the ability to fix atmospheric nitrogen in symbiosis with Rhizobium, enriching marginal soils with this essential nutrient and reducing the need for artificial fertilizers. Additionally, lupine produces seeds with a high protein content, making it valuable for animal feed production. However, drought negatively affects lupine development, its mutualistic relationship with bacteria, and overall yield. To understand how lupine responds to this stress, global transcriptome sequencing was conducted, along with in-depth biochemical, chromatography, and microscopy analyses of roots subjected to drought. The results presented here contribute to strategies aimed at mitigating the effects of water deficit on lupine growth and development. Based on RNA-seq, drought-specific genes were identified and annotated to biological pathways involved in phytohormone biosynthesis/signaling, lipid metabolism, and redox homeostasis. Our findings indicate that drought-induced disruption of redox balance characterized by the upregulation of reactive oxygen species (ROS) scavenging enzymes, coincided with the accumulation of lipid-metabolizing enzymes, such as phospholipase D (PLD) and lipoxygenase (LOX). This disruption also led to modifications in lipid homeostasis, including increased levels of triacylglycerols (TAG) and free fatty acids (FFA), along with a decrease in polar lipid content. Additionally, the stress response involved alterations in the transcriptional regulation of the linolenic acid metabolism network, resulting in changes in the composition of fatty acids containing 18 carbons. The first comprehensive global transcriptomic profiles of lupine roots, combined with the identification of key stress-responsive molecules, represent a significant advancement in understanding lupine's responses to abiotic stress. The increased expression of the Δ12DESATURASE gene and enhanced PLD activity lead to higher level of linoleic acid (18:2), which is subsequently oxidized by LOX, resulting in membrane damage and malondialdehyde (MDA) accumulation. Oxidative stress elevates the activities of superoxide dismutase (SOD), ascorbate peroxidase (APX), and catalase (CAT), while the conversion of FFAs into TAGs provides protection against ROS. This research offers valuable molecular and biochemical candidates with significant potential to enhance drought tolerance . It enables innovative strategies in lupine breeding and crop improvement to address critical agricultural challenges.

Probabilistic Modeling Geometric Tolerance and Low Cycle Fatigue Life of Gas Turbine Compressor Blade

Abstract This paper presents a probabilistic low cycle fatigue (LCF) assessment for geometric tolerances on high load contact surfaces of gas turbine compressor blades. The typical patterns of the geometric deviations for the root contact flank of the compressor blades are identified and characterized according to coordinate measurement machine (CMM) measurements of the blade root. These typical patterns are closely related to the root form manufacture tools and process. Finite element (FE) models for the typical geometric deviation patterns are created based on nodal coordinates transformation of the surface nodes on the blade root contact flanks and radius. An optimized blade root profile tolerance is established, which enables significant cost saving. The elastic-plastic FE analysis with nonlinear contact model, material strain-life test, response surface, and constrained Monte Carlo simulation are used to create a probabilistic LCF life model for the optimized tolerance. The model quantifies the effect of the geometric deviations, blade mass, and material property on the blade LCF life. The result shows that with the optimized tolerance, the probability of blade LCF failure is very low and acceptable. It is also shown that the strain life material property is the most critical factor for the LCF failure. The root profile tolerance and blade mass are seen to have a much weaker effect on the blade LCF life.

ABA deficiency and its impact on ion and metabolite profiles in tomato roots under single and combined stress conditions

Abscisic acid (ABA) plays a crucial role in the stress response of plants. Although the impact of ABA on individual stresses has been extensively studied, there is less research on its role in plants grown under stress combination, such as salinity and high temperature. This study analyzes the response at the ionomic and metabolomic levels of tomato roots to ABA deficiency under single salinity or heat stress, as well as under the combination of both stresses, using ABA-deficient (flacca, flc) tomato plants. ABA was found to be crucial in ionic regulation, particularly for Na, K, Ca, and other ions such as Cu, Mn, Zn, Mo, and Fe. However, its influence depended on the type of stress applied, indicating the complexity of plant responses to these adverse environmental factors. In our study, phenylpropanoids, terpenoids, and nitrogenous compounds were the metabolites most affected by endogenous ABA concentration and environmental treatment. On the other hand, the application of exogenous ABA to flc mutants did not fully restore root dry weight, although it did cause significant changes at the ionomic and metabolomic levels. Salinity and heat applied in combination aggravated the vulnerability of flc mutants compared to single stresses, making the application of exogenous ABA more effective under single stresses than under the combined stresses. Finally, a correlation analysis between the ionome and metabolome revealed that the accumulation or deficiency of some ions (i.e., Na, Zn, and Fe) was correlated with the abundance of important metabolites related to amino acid biosynthesis and terpenoid metabolism, among others.

Compost incorporation and wildflowers introduction for stormwater infiltration and erosion-control vegetation cover establishment in post-construction landscapes

Urban and suburban development frequently disturbs and compacts soils, reducing infiltration rates and fertility, posing challenges for post-development vegetation establishment, and contributing to soil erosion. This study investigated the effectiveness of compost incorporation in enhancing stormwater infiltration and vegetation establishment in urban landscapes. Experimental treatments comprised a split-split plot design of vegetation mix (grass, wildflowers, and grass-wildflowers) as main plot, ground cover (hydro-mulch and excelsior) as subplot, and compost (30% Compost and No-Compost) as sub-subplot factors. Wildflower inclusion was motivated by their recognized ecological benefits, including aesthetics, pollinator habitat, and deep root systems. Vegetation cover was assessed using RGB (Red-Green-Blue) imagery and ArcGIS-based supervised image classification. Over a 24-month period, bulk density, infiltration rate, soil penetration resistance, vegetation cover, and root mass density were assessed. Results highlighted that Compost treatments consistently reduced bulk density by 19–24%, lowered soil penetration resistance to under 2 MPa at both field-capacity and water-stressed conditions, and increased infiltration rate by 2–3 times compared to No-Compost treatments. Vegetation cover assessment revealed rapid establishment with 30% compost and 60:40 grass-wildflower mix, persisting for an initial 12 months. Subsequently, all treatments exhibited similar vegetation coverage from 13 to 24 months, reaching 95–100% cover. Compost treatments had significantly higher root mass density within the top 15 cm than No-Compost, but compost addition did not alter the root profile beyond the 15 cm depth incorporation depth. The findings suggest that incorporating 30% compost and including a wildflower or grass-wildflower mix appears to be effective in enhancing stormwater infiltration and provides rapid erosion control vegetation cover establishment in post-construction landscapes.

Exogenous stimulation of Tanacetum vulgare roots with pipecolic acid leads to tissue-specific responses in terpenoid composition.

Tanacetum vulgare L., tansy, is a perennial plant with highly variable terpenoid composition, with mono- and sesquiterpenoids being the most abundant. The high diversity of terpenoids plays an important role in mediating ecological interactions. However, the distribution of terpenoids in different tissues and inducibility of terpenoids in these tissues via biotic stress are poorly understood. We investigated changes in terpenoid profiles and concentrations in different organs following treatment of roots with pipecolic acid (Pip), a non-proteinogenic amino acid that triggers defence responses leading to induce systemic resistance (SAR) in plants. Tansy leaves and midribs contained mainly monoterpenoids, while coarse and fine roots contained mainly sesquiterpenoids. Rhizomes contained terpenoid profiles of both midribs and roots but also unique compounds. Treatment with Pip led to an increase in concentrations of mono- and sesquiterpenoids in all tissues except rhizomes. However, significantly more sesquiterpenoids was formed in root tissues in response to Pip treatment, compared to shoots. The metabolic atlas for terpenoids presented here shows that there is exceptionally strong differentiation of terpenoid patterns and terpenoid content in different tissues of tansy. This, together with differential inducibility by Pip, suggests that the chemical diversity of terpenoids may play an important role in tansy ecological interactions and defence against biotic stressors that feed on below- and aboveground organs.

Comparative proteomic discovery of salt stress response in alfalfa roots and overexpression of MsANN2 confers salt tolerance

Soil salinity constrains growth, development and yield of alfalfa (Medicago sativa L.). To illustrate the molecular mechanisms responsible for salt tolerance, a comparative proteome analysis was explored to characterize protein profiles of alfalfa seedling roots exposed to 100 and 200 mM NaCl for three weeks. There were 52 differentially expressed proteins identified, among which the mRNA expressions of 12 were verified by Real-Time-PCR analysis. The results showed increase in abundance of ascorbate peroxidase, POD, CBS protein and PR-10 in salt-stressed alfalfa, suggesting an effectively antioxidant and defense systems. Alfalfa enhanced protein quality control system to refold or degrade abnormal proteins induced by salt stress through upregulation of unfolded protein response (UPR) marker PDIs and molecular chaperones (eg. HSP70, TCP-1, and GroES) as well as the ubiquitin‐proteasome system (UPS) including ubiquitin ligase enzyme (E3) and proteasome subunits. Upregulation of proteins responsible for calcium signal transduction including calmodulin and annexin helped alfalfa adapt to salt stress. Specifically, annexin (MsANN2), a key Ca2+-binding protein, was selected for further characterization. The heterologous of the MsANN2 in Arabidopsis conferred salt tolerance. These results provide detailed information for salt-responsive root proteins and highlight the importance of MsANN2 in adapting to salt stress in alfalfa.

Shear characteristics of root–matrix composites under various interface friction and moisture content conditions

Analysing the composite's adhesion mechanism is necessary to gain a deep understanding of the pipeline blockage phenomenon encountered during negative pressure matrix removal. This study considers the interface suction and liquid bridge changes between the roots and the matrix. In particular, the liquid bridge volume and the interface's effective stress parameters were combined to establish a theoretical model of the shear strength of the root–matrix composite. The main factors affecting root–matrix composite adhesion stability were the root friction coefficient and the composite moisture content. Regarding the influence of the root friction coefficient, the surface structures of the primary and lateral roots were observed using a laser confocal microscope. Using the principal component analysis method, the main factors influencing the friction properties of the root system were identified as the taproot's maximum valley depth (Rv) and the average roughness (Ra) of the profile, as well as the lateral root's maximum peak-to-valley height (Rz) and the average roughness (Rq) of the lateral root profile. The influence of both the main and lateral roots cannot be overlooked when removing inferior seedlings from the substrate. Furthermore, the bond efficiency of the root–matrix composite was calculated, revealing values of 16.03%, 49.87%, and 58.31% under low, medium, and high moisture content conditions, respectively. Finally, direct shear tests were conducted on the complex under dry-wet-dry conditions, yielding an internal friction angle of 14.1656° and a cohesion force of 1.738 ± 0.3 kPa at a water content of 20% (dry-wet). In conclusion, it is recommended to perform the negative pressure removal of inferior seedling substrate blocks during the seedling stage with low water content and underdeveloped root systems. Related research lays the foundation for preventing blockages in negative pressure pipelines.

Unveiling the phytochemical profile and antioxidant activity of roots from six Polygala species

The genus Polygala (Polygalaceae), comprising about 670 species worldwide, has more than 40 species in China. The roots of Polygala tenuifolia Willd., Polygala sibirica L., and Polygala japonica Houtt. are recorded in the Chinese Pharmacopeia. Other closely related plants of the Polygala genus are also widely used in the folk medicine of southern China, such as Polygala fallax Hemsl., Polygala arvensis Willd., and Polygala glomerata Lour. To systematically compare the chemical compositional and elucidate characteristic compounds among the Polygala genus, six Polygala species, namely P. tenuifolia, P. sibirica, P. japonica, P. fallax, P. arvensis and P. glomerata, underwent comprehensive phytochemical studies using the ultra performance liquid chromatography-quadrupole time-of-flight tandem mass Spectrometry (UPLC-Q-TOF-MS/MS) technique, resulting in the identification of 154 compounds, consisting of 62 oligosaccharide esters (40.26 %), 58 saponins (37.66 %), 29 xanthones (18.83 %), and 5 other chemicals (3.25 %). Based on the Masslynx computational tool, a comprehensive comparative phytochemical profiling was achieved and revealed differences in composition among the six Polygala species. P. sibirica exhibited higher levels of specific compounds and was more closely related to P. tenuifolia. Meanwhile, P. japonica showed greater similarity to P. fallax, P. arvensis, and P. glomerata. Oligosaccharide esters and triterpene saponins were more abundant in P. sibirica and P. tenuifolia than in other species. Furthermore, the antioxidant activities (1,1-diphenyl-2-acrylohydrazide [DPPH], 2,2′-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt [ABTS], copper ion reducing antioxidant capacity [CUPRAC], and ferric ion-reducing antioxidant power [FRAP]) of the six species were evaluated. Among them, P. tenuifolia demonstrated superior antioxidant potential, with a lower half-maximal inhibitory concentration (IC50) value for scavenging DPPH radicals and excellence in CUPRAC (119.85 ± 16.28 μM/0.01 g) compared to other plants. P. japonica showed higher ABTS (98.94 ± 0.03 μM/0.01 g) and FRAP (42.58 ± 0.08 μM/0.01 g). Total flavonoids showed remarkable antioxidant capabilities among the six medicinal plants. Total saponins and phenolics also contributed to the antioxidant potential of these plants. The systematic data and results obtained may provide methodological support for further evaluating the potential use of folk Polygala plants as new effective materials in various commercial sectors, including food, cosmetic, and pharmaceutical industries.

Cr(VI) behaves differently than Cr(III) in the uptake, translocation and detoxification in rice roots

Excessive accumulation of chromium (Cr) causes severe damage to both physiological and biochemical processes and consequently growth repression in plants. Hexavalent chromium [Cr(VI)]-elicited alterations in plants have been widely elucidated at either physiological or molecular level, whereas little is known about trivalent chromium [Cr(III)]. Here, we found that both Cr(III) and Cr(VI) significantly inhibited root growth in rice plants. However, rice plants under Cr(VI) showed significantly less inhibition in root growth than those under Cr(III) at low levels, which might be attributed to the different hormetic effects of Cr(III) and Cr(VI) on rice plants. It was unexpected that Cr(III) could be actively taken up by rice roots similarly to Cr(VI); whereas they exhibited different kinetic uptake patterns. Furthermore, root-to-shoot Cr translocation under Cr(VI) was much lower than that under Cr(III). These results indicate that the uptake, translocation, and toxicity of Cr(III) differed greatly from those of Cr(VI). Transcriptome profiling of rice roots revealed that a series of gene families involved in detoxification, including ATP-binding cassette (ABC) transporters, multidrug and toxic compound extrusion proteins (MATEs), and Tau class glutathione S-transferases (GSTUs), were significantly associated with Cr accumulation and detoxification in rice roots. In addition, much more members of these gene families were upregulated by Cr(VI) compared to Cr(III), suggesting their vital roles in Cr uptake, translocation, and detoxification, especially under Cr(VI) stress. Further comparison of gstu9 and gstu10/50 mutants with their wild type confirmed that GSTUs play complex roles in the intracellular Cr transport and redox homeostasis during Cr(III) or Cr(VI) stress. Taken together, our findings provides new insights into the differential behaviors of Cr(III) and Cr(VI) in rice roots, as well as new candidate genes such as OsABCs and OsGSTUs, to further elucidate the mechanisms of the uptake, translocation, and detoxification of Cr(III) and Cr(VI).

Maize zinc uptake is influenced by arbuscular mycorrhizal symbiosis under various soil phosphorus availabilities.

The antagonistic interplay between phosphorus (P) and zinc (Zn) in plants is well established. However, the molecular mechanisms mediating those interactions as influenced by arbuscular mycorrhizal (AM) symbiosis remain unclear. We investigated Zn concentrations, root AM symbiosis, and transcriptome profiles of maize roots grown under field conditions upon different P levels. We also validated genotype-dependent P-Zn uptake in selected genotypes from a MAGIC population and conducted mycorrhizal inoculation experiments using mycorrhizal-defective mutant pht1;6 to elucidate the significance of AM symbiosis in P-Zn antagonism. Finally, we assessed how P supply affects Zn transporters and Zn uptake in extraradical hyphae within a three-compartment system. Elevated P levels led to a significant reduction in maize Zn concentration across the population, correlating with a marked decline in AM symbiosis, thus elucidating the P-Zn antagonism. We also identified ZmPht1;6 is crucial for AM symbiosis and confirmed that P-Zn antagonistic uptake is dependent on AM symbiosis. Moreover, we found that high P suppressed the expression of the fungal RiZRT1 and RiZnT1 genes, potentially impacting hyphal Zn uptake. We conclude that high P exerts systemic regulation over root and AM hyphae-mediated Zn uptake in maize. These findings hold implications for breeding Zn deficiency-tolerant maize varieties.

Glucosinolates in non-Brassicales plant species: Critical literature evaluation and testing of two high chemical quality reports

Glucosinolates (GSLs) are secondary metabolites mainly found in the plant order Brassicales. We critically evaluate reports of GSLs in other orders of flowering plants, propose standards for future reports and subject two cases to rigorous testing. Reports of GSLs in non-Brassicales species should live up to state-of-the-art scientific standards concerning chemical evidence, botanical evidence and biological replication. Occurrence of GSLs in the family Putranjivaceae, order Malpighiales (genera Putranjiva and Drypetes) was reasonably supported, but state-of-the-art confirmation was required. Hence, the taxonomic identity of Putranjiva roxbughii seeds with the previously known GSL profile was confirmed using DNA-based methods. Similarly, good suggestive evidence exist from the family Violaceae, order Malpighiales, but in need of confirmation. No other report of any GSL in a non-Brassicales species meet the proposed scientific standards, but suggestive evidence exists for the family Phytolaccaceae, order Caryophyllales and to a lesser extent family Celastraceae, order Celastrales. A recent report of a GSL in a tropical plant suggested to be a species in the order Sapindales was subjected to a rigorous testing in terms of chemical analysis, biological replication and botanical identification including DNA sequencing. We confirmed the original report concerning chemical structure and reproducibility but revised the botanical identification to a species from the Brassicales order (family Capparidaceae). Hence this paper also reports myrosinase activity, isothiocyanate-type GSL products from roots and stems, and GSL profile of roots, stems, leaves and fruits of Capparis sepiaria L., dominated by Leu-derived 2-methylpropyl GSL in vegetative parts, Val-derived 1-methylethyl GSL and Ile-derived 1-methylpropyl GSL in fruits, and additionally Trp-derived indol-3-ylmethyl GSL and 4-hydroxyindol-3-ylmethyl GSL in immature fruits. Several other GSLs were searched for and conclusively not found above the limit of detection.

Morphological and proteomic study of waterlogging tolerance in cotton

Floating seedling cultivation technique is a novel seedling method in cotton and it provides an ideal model to study cotton growing under waterlogging stress. Morphological character and proteomic profile of the primary root from the seedling cultured by the new technology were evaluated in this study. Compared to seedlings cultured by the traditional method, the diameter of the taproot from floating technology is small at all five seedling stages from one-leaf stage to five-leaf stage. There are similar changes between the thickness of cortex and diameter of stele, which increased from the one- to the two-leaf stage but decreased from the two- to the five-leaf stage. At the one-leaf stage, the number and volume of mitochondria in the primary root-tip cells were less than those in the control. At the two-leaf stage, there was significantly less electron-dense material in the primary root-tip cells than those in the control group. From the one- to the two-leaf stage, the vacuole volume was significantly smaller than that in the control. Total 28 differentially expressed proteins were revealed from aquatic and control group roots of cotton seedlings at the three-leaf stage by two-dimensional electrophoresis, which included 24 up-regulated and four down-regulated proteins. The relative expression of the phosphoglycerate kinase (PGK) gene in aquatic roots increased from the one- to the four-leaf stage but declined rapidly from the four- to the five-leaf stage. The relative expression of the 14–3-3b gene tended to decrease from the one- to the five-leaf stage. The PGK and 14–3-3b genes were specifically expressed in the aquatic roots at the three-leaf stage. In brief, these changes induced waterlogging resistance in the aquatic roots of cotton seedlings in the floating nursery, thereby causing the roots to adapt to the aquatic environment, promoting the growth and development of cotton seedlings.

NMR Metabolomics of Arctium lappa L., Taraxacum officinale and Melissa officinalis: A Comparison of Spontaneous and Organic Ecotypes.

Officinal plants are a source of metabolites whose chemical composition depends on pedoclimatic conditions. In this study, the NMR-based approach was applied to investigate the impacts of different altitudes and agronomical practices (Land, Mountain Spontaneous, and Organically Grown Ecotypes, namely LSE, MSE, and OE, respectively) on the metabolite profiles of Burdock root, Dandelion root and aerial part, and Lemon balm aerial part. Sugars, amino acids, organic acids, polyphenols, fatty acids, and other metabolites were identified and quantified in all samples. Some metabolites turned out to be tissue-specific markers. Arginine was found in roots, whereas myo-inositol, galactose, glyceroyldigalactose moiety, pheophytin, and chlorophyll were identified in aerial parts. Caftaric and chicoric acids, 3,5 di-caffeoylquinic acid, and chlorogenic and rosmarinic acids were detected in Dandelion, Burdock and Lemon balm, respectively. The metabolite amount changed significantly according to crop, tissue type, and ecotype. All ecotypes of Burdock had the highest contents of amino acids and the lowest contents of organic acids, whereas an opposite trend was observed in Lemon balm. Dandelion parts contained high levels of carbohydrates, except for the MSE aerial part, which showed the highest content of organic acids. The results provided insights into the chemistry of officinal plants, thus supporting nutraceutical-phytopharmaceutical research.

Overexpression of phosphatidylserine synthase IbPSS1 enhances salt tolerance by stimulating ethylene signaling-dependent lignin synthesis in sweetpotato roots

Phosphatidylserine (PS) is an important lipid signaling required for plant growth regulation and salt stress adaptation. However, how PS positively regulate plant salt tolerance is still largely unknown. In this study, IbPSS1-overexpressed sweetpotato plants that exhibited overproduction of PS was employed to explore the mechanisms underlying the PS stimulation of plant salt tolerance. The results revealed that the IbPSS1-overexpressed sweetpotato accumulated less Na+ in the stem and leaf tissues compared with the wild type plants. Proteomic profile of roots showed that lignin synthesis-related proteins over-accumulated in IbPSS1-overexpressed sweetpotato. Correspondingly, the lignin content was enhanced but the influx of Na + into the stele was significantly blocked in IbPSS1-overexpressed sweetpotato. The results further revealed that ethylene synthesis and signaling related genes were upregulated in IbPSS1-overexpressed sweetpotato. Ethylene imaging experiment revealed the enhancement of ethylene mainly localized in the root stele. Inhibition of ethylene synthesis completely reversed the PS-overproduction induced lignin synthesis and Na+ influx pattern in stele tissues. Taken together, our findings demonstrate a mechanism by which PS regulates ethylene signaling and lignin synthesis in the root stele, thus helping sweetpotato plants to block the loading of Na+ into the xylem and to minimize the accumulation of Na+ in the shoots.

Abstract 2122: A Multiomic Timecourse Atlas Of Murine Vascular Disease Smooth Muscle Cell Transition Phenotypes And Their Perturbation With Tcf21 Knockout

Background: Vascular smooth muscle cells (SMC) contribute to heritable CAD risk and undergo cell changes to fibroblast-like (FMC) and osteochondrogenic (CMC) phenotypes. We perform molecular characterization of this transition process over the course of atherosclerosis development to better understand how causal SMC CAD genes such as TCF21 drive the phenotypic transition process to alter CAD risk. Methods/Results: Deep multiomic profiling of aortic roots from control atherosclerosis model ( Myh11Cre ERT2 , ROSA tdT/+ , ApoE -/- ) mice with SMC specific lineage tracing on high fat diet were harvested for 7 scRNA and 6 scATAC time points across 16 weeks. Similarly, aortic roots from Tcf21 knockout ( Myh11Cre ERT2 , Tcf21 ΔSMC/ΔSMC , ROSA tdT/+ , ApoE -/- ) were collected at 3 timepoints for paired scRNA/scATAC. Waddington-Optimal Transport (WOT) mapped transcriptional trajectories across SMC lineage clusters which terminate in FMC and CMC phenotype clusters. PANDO/CellOracle frameworks were used to create gene regulatory networks with the ability to model SMC transition perturbations in silico . These analyses generated a multiomic timecourse atlas demonstrating the lineage traced phenotypic progression of SMC to FMC and CMC. Upon knockout of Tcf21 , we discern notable shifts in the SMC to FMC transition characterized by differential scRNA transcriptional pathways and scATAC shifts in transcription factor (TF) motif accessibility which also overlap with WOT predicted TF enrichment for each cell state. These integrative analyses revealed Tcf21 regulation of Cebpb and the Tead1 -Hippo pathways as novel mechanisms for mediating its role in modulation of disease related processes such as inflammation, response to TGF- β signaling and cell proliferation. Further mechanistic validation is performed through a combination of TF binding site analysis with TEAD1 and CEBPB ChIP-Seq in human coronary artery SMCs, dual luciferase reporter assays and proximity ligation assays. Conclusion: We construct a single cell atherosclerosis timecourse to model mouse SMC cell states and perturb CAD gene Tcf21 to elucidate the interplay between epigenetic and transcriptional mechanisms which affect key SMC transition elements such as CEBPB and the TEAD1 -Hippo axis.

Vertical root profiles of grey alder (Alnus incana) trees growing in highly disturbed river environments

AbstractThe ability of plants to colonize the fluvial environment and withstand uprooting by floods is largely controlled by the anchoring effect of roots. We characterized the root architecture and tensile strength of Alnus incana, a riparian tree species of the Betulaceae family for which there are no systematic observations of its vertical root structure. Four A. incana individuals and two nearby Populus nigra 3–10 years old growing on bars in gravel‐bed rivers were excavated. Their root structure was characterized in terms of root diameter, age, and depth and was related to sediment grain size and scour or deposition by floods. Root tensile strength was also measured as a function of root diameter using a load cell and displacement transducer attached to individual roots. The architecture of A. incana roots differed from that of nearby P. nigra, as all roots were in fine, sandy sediments, growing in one or more dense radial layers of which the most prominent was 0.2–0.3 m below the surface. The layers reflect deposition of fine sediments during floods. New fine sediment deposits promote the growth of a new root layer close to the aggraded ground surface. Root tensile strength was similar to Salicaceae species. These observations indicate that A. incana colonizes habitats that have already received fine sediment deposition, most likely induced by other young plants, especially Salicaceae species. A. incana then provides a high near‐surface root biomass, potentially further stabilizing surfaces and playing a complementary role as an ecosystem engineer.

Transcriptomic and Lipidomic Analysis Reveals Complex Regulation Mechanisms Underlying Rice Roots' Response to Salt Stress.

Rice (Oryza sativa L.), a crucial food crop that sustains over half the world's population, is often hindered by salt stress during various growth stages, ultimately causing a decrease in yield. However, the specific mechanism of rice roots' response to salt stress remains largely unknown. In this study, transcriptomics and lipidomics were used to analyze the changes in the lipid metabolism and gene expression profiles of rice roots in response to salt stress. The results showed that salt stress significantly inhibited rice roots' growth and increased the roots' MDA content. Furthermore, 1286 differentially expressed genes including 526 upregulated and 760 downregulated, were identified as responding to salt stress in rice roots. The lipidomic analysis revealed that the composition and unsaturation of membrane lipids were significantly altered. In total, 249 lipid molecules were differentially accumulated in rice roots as a response to salt stress. And most of the major phospholipids, such as phosphatidic acid (PA), phosphatidylcholine (PC), and phosphatidylserine (PS), as well as major sphingolipids including ceramide (Cer), phytoceramide (CerP), monohexose ceramide (Hex1Cer), and sphingosine (SPH), were significantly increased, while the triglyceride (TG) molecules decreased. These results suggested that rice roots mitigate salt stress by altering the fluidity and integrity of cell membranes. This study enhances our comprehension of salt stress, offering valuable insights into changes in the lipids and adaptive lipid remodeling in rice's response to salt stress.

Single-Nucleus Multiomic Analyses Identifies Gene Regulatory Dynamics of Phenotypic Modulation in Human Aneurysmal Aortic Root.

Aortic root aneurysm is a potentially life-threatening condition that may lead to aortic rupture and is often associated with genetic syndromes, such as Marfan syndrome (MFS). Although studies with MFS animal models have provided valuable insights into the pathogenesis of aortic root aneurysms, this understanding of the transcriptomic and epigenomic landscape in human aortic root tissue remains incomplete. This knowledge gap has impeded the development of effective targeted therapies. Here, this study performs the first integrative analysis of single-nucleus multiomic (gene expression and chromatin accessibility) and spatial transcriptomic sequencing data of human aortic root tissue under healthy and MFS conditions. Cell-type-specific transcriptomic and cis-regulatory profiles in the human aortic root are identified. Regulatory and spatial dynamics during phenotypic modulation of vascular smooth muscle cells (VSMCs), the cardinal cell type, are delineated. Moreover, candidate key regulators driving the phenotypic modulation of VSMC, such as FOXN3, TEAD1, BACH2, and BACH1, are identified. In vitro experiments demonstrate that FOXN3 functions as a novel key regulator for maintaining the contractile phenotype of human aortic VSMCs through targeting ACTA2. These findings provide novel insights into the regulatory and spatial dynamics during phenotypic modulation in the aneurysmal aortic root of humans.

Tooth profile design and meshing characteristics analysis of internal meshing gears based on variable center meshing line

A design method of internal meshing gear based on variable center meshing line (VCML) is presented in this paper. The meshing line is an arc line connecting the intersection of the indexing circle connecting the inner and outer gears and the intersection of the tooth top circle, and the center of the line of engagement freely slides on the vertical bisection line of the line connecting the two intersection points. The top tooth profile equation of internal and external gears is derived by rack equation. According to the normal method of gear profile, the equation of gear root meshing line is derived by using the tooth top profile equation of the gear. According to the principle of plane meshing, the root profile equation of gear is derived by using the root meshing line equation of gear. The tooth profile of VCML gear can be deduced quickly by adjusting the center position of the meshing line. The stress, meshing stiffness, transmission error, contact ratio and sliding ratio of the VCML gears are analyzed by finite element method, and the area of significant performance improvement of the meshing line center of the VCML gears is found. The research results show that compared with involute gears, the maximum average stress of VCML gears is reduced by 64.99%, the meshing stiffness is increased by 193.67%, and the transmission error is reduced by 65.95%. This method improves the efficiency of new tooth profile design and transmission performance. By changing the center coordinates of the meshing line, the tooth profile of the VCML gear can be quickly redesigned, which greatly improves the efficiency of the new tooth profile design and transmission performance. This design method provides a new idea for the tooth profile design of internal meshing gear.

The metabolic fingerprint of Scots pine-root and needle metabolites show different patterns in dying trees.

The loss of leaves and needles in tree crowns and tree mortality are increasing worldwide, mostly as a result of more frequent and severe drought stress. Scots pine (Pinus sylvestris L.) is a tree species that is strongly affected by these developments in many regions of Europe and Asia. So far, changes in metabolic pathways and metabolite profiles in needles and roots on the trajectory toward mortality are unknown, although they could contribute to a better understanding of the mortality mechanisms. Therefore, we linked long-term observations of canopy defoliation and tree mortality with the characterization of the primary metabolite profile in needles and fine roots of Scots pines from a forest site in the Swiss Rhone valley. Our results show that Scots pines are able to maintain metabolic homeostasis in needles over a wide range of canopy defoliation levels. However, there is a metabolic tipping point at around 80-85% needle loss. Above this threshold, many stress-related metabolites (particularly osmoprotectants, defense compounds and antioxidants) increase in the needles, whereas they decrease in the fine roots. If this defoliation tipping point is exceeded, the trees are very likely to die within a few years. The different patterns between needles and roots indicate that mainly belowground carbon starvation impairs key functions for tree survival and suggest that this is an important factor explaining the increasing mortality of Scots pines.