Pseudounipolar neurons in the dorsal root ganglia(DRG),as the central nodes of primary sensory afferents,possess a distinctive T-junction that is not merely a morphological peculiarity but also performs complex roles ...Pseudounipolar neurons in the dorsal root ganglia(DRG),as the central nodes of primary sensory afferents,possess a distinctive T-junction that is not merely a morphological peculiarity but also performs complex roles in rapid,multiplexed shunting and regulation of sensory signals.This specialized geometry enables separation,filtering,and feedback regulation of neuronal signals,thereby coordinating peripheral and central responses at multiple levels.Recent advances,including spatial transcriptomics,single-cell sequencing,super-resolution microscopy,organoid models,and novel electrophysiological methods,have permitted more precise dissection of the T-junction's molecular composition,ion-channel distribution,and electrophysiological properties.Here,we review current knowledge of the T-junction's developmental regulation and multilayered molecular networks,and we detail its functional alterations in both physiological signaling and pathological pain states,with particular emphasis on ion-channel modulation,signal attenuation,and selective transmission mechanisms.Finally,we discuss contemporary pain-intervention approaches and prospects for precision-targeted therapies,aiming to provide a theoretical foundation for future studies in pain physiology and clinical translation.展开更多
背景:近年来,生物陶瓷材料因具有良好的生物相容性和封闭性能逐渐成为根尖倒充填的首选材料,其中生物陶瓷材料C-Root BP、iRoot BP Plus均具有良好的生物相容性和封闭性能。目的:对比体外环境下C-Root BP与iRoot BP Plus材料的根尖封闭...背景:近年来,生物陶瓷材料因具有良好的生物相容性和封闭性能逐渐成为根尖倒充填的首选材料,其中生物陶瓷材料C-Root BP、iRoot BP Plus均具有良好的生物相容性和封闭性能。目的:对比体外环境下C-Root BP与iRoot BP Plus材料的根尖封闭性能及抗力强度。方法:于2022年6月至2024年6月期间,收集石家庄市第二医院口腔科因正畸或牙周病新鲜拔除的单根离体牙56颗,随机分4组处理:iRoot BP Plus组(n=16)、C-Root BP组(n=16)根管预备和消毒后分别采用iRoot BP Plus、C-Root BP材料进行根尖倒充填,阳性对照组(n=16)根管预备和消毒后使用蒸馏水进行根尖倒充填,阴性对照组(n=8)仅行根管预备和消毒(不进行根尖倒充填处理),采用染料渗透法检测根尖封闭性;制作根管细菌渗漏体外模型,评价细菌微渗漏发生情况;采用薄片推出实验检测填充材料与牙本质之间的粘连强度,并在显微镜下观察断裂形式。结果与结论:(1)染料染色7 d后,阳性对照组染料渗透长度大于iRoot BP Plus组、C-Root BP组(P<0.05),iRoot BP Plus组和C-Root BP组染料渗透长度比较差异无显著性意义(P>0.05);(2)经过90 d培养,阳性对照组细菌微渗漏发生率高于iRoot BP Plus组、C-Root BP组(P<0.05),iRoot BPPlus组和C-Root BP组细菌微渗漏发生率比较差异无显著性意义(P>0.05);(3)C-Root BP组填充材料与牙本质之间的粘连强度大于iRootBP Plus组(P<0.05),两组断裂面断裂形式比较差异无显著性意义(P>0.05);(4)结果表明,采用C-Root BP和iRoot BP Plus材料进行根尖倒充填可产生相似的根尖封闭效果,并且断裂形式也基本一致,但C-Root BP材料具有良好的粘连强度。展开更多
Soil compaction often imposes stress on root development and plant survival.However,root anatomical responses that enable persistent root growth and functioning under soil compaction remain unclear.We grew 10 herbaceo...Soil compaction often imposes stress on root development and plant survival.However,root anatomical responses that enable persistent root growth and functioning under soil compaction remain unclear.We grew 10 herbaceous species differing substantially in lateral root diameter,in soils with low(1.0 g cm^(-3))and high(1.4 g cm^(-3))bulk density,and assessed root traits including root biomass,anatomical structures,and respiration rates.Greater root thickening upon soil compaction was found in species with thicker first-order lateral roots,mainly due to larger cortical cell size.Both xylem vessel diameter and wall thickness increased more in compacted soils in these species.Despite these anatomical shifts,root respiration rate responded little to soil compaction across most species,likely due to the opposite investment in cortical cells and xylem vessels.Notably,root biomass,independent of root respiration rate and anatomical structures,determined whole-plant growth under soil compaction.Our study reveals two independent strategies of root response to soil compaction:anatomical remodeling for mechanical and metabolic maintenance,and root biomass investment for resource acquisition.These findings offer new insights for breeding and selecting species tolerant to soil compaction and highlight multidimensional strategies of plant adaptation to physical stress.展开更多
The shift from seedling transplanting to direct-seeding cultivation in rice demands robust root systems for early seedling establishment and yield stability.While the pleiotropic gene OsSP3(also designated TAC4 or SG2...The shift from seedling transplanting to direct-seeding cultivation in rice demands robust root systems for early seedling establishment and yield stability.While the pleiotropic gene OsSP3(also designated TAC4 or SG2)is known to regulate aboveground traits,including tiller angle,grain size,and panicle development,its function in root morphogenesis remains uncharacterized.展开更多
Green manuring is essential for improving soil quality and nutrient uptake.With the gradual depletion of phosphorus(P)resources,more attention is being paid to the role of green manures in cultivation systems,such as ...Green manuring is essential for improving soil quality and nutrient uptake.With the gradual depletion of phosphorus(P)resources,more attention is being paid to the role of green manures in cultivation systems,such as maize-green manure intercropping,to find possible pathways for enhancing soil P utilization.A maize-green manure intercropping experiment was started in 2009 to investigate the effects and mechanisms for enhancing P uptake and yield in maize.Three species of green manures(hairy vetch(HV),needle leaf pea(NP),sweet pea(SP))and a sole maize treatment(CK)were used,resulting in four treatments(CK,HVT,NPT,and SPT)in the experiment.During 2020-2023,the intercropping treatments enhanced maize yields in 2020 and 2021,particularly in HVT with increases of 13.7%(1.96 t ha^(-1))and 13.0%(2.13 t ha^(-1))compared with CK,respectively.Grain P accumulation of maize was significantly higher in the intercropping treatments than CK in 2020,2021,and 2023,and with an average increase of 10.6%over the four years(5.2% for NPT,10.8% for SPT and 15.9% for HVT)compared with CK.Intercropping promoted maize growth with a greater root length density and a higher organic acid release rate.HVT changed the soil properties more dramatically than the other treatments,with increases in the acid phosphatase and alkaline phosphatase activities of 29.8 and 38.5%,respectively,in the topsoil(0-15 cm),while the soil p H was reduced by 0.37 units compared to CK(p H=8.44).Intercropping treatments facilitated the conversion of non-labile P to mod-labile P and stimulated the growth of soil bacteria in the topsoil.Compared with CK,the relative abundance of Gemmatimonadota,known for accumulating polyphosphate,and Actinobacteriota,a prominent source of bioactive compounds,increased significantly in the intercropping treatments,especially in HVT and SPT.A PLS-PM analysis showed that intercropping promoted soil P mobilization and the enrichment of beneficial bacteria by regulating maize root morphology and physiology.Our results highlight that maize-green manure intercropping optimizes root traits,soil properties and bacterial composition,which contribute to greater maize P uptake and yield,providing an effective strategy for sustainable crop production.展开更多
Optimizing plant architecture for specific cultivation methods is essential for enhancing fruit productivity.Unlike indeterminate growth plants,the total productivity of determinate growth plants relies on cumulative ...Optimizing plant architecture for specific cultivation methods is essential for enhancing fruit productivity.Unlike indeterminate growth plants,the total productivity of determinate growth plants relies on cumulative fruit production and synchronized fruit ripening from both main and axillary shoots.Here,we focused on SlD14and SlMAX1,two key genes involved in the regulation of strigolactone(SL)signaling and biosynthesis,with the goal of maximizing yield and syn chronizing fruit ripening by fine-tuning axillary shoot growth.Using clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated protein 9(Cas9)technology,we found that the sld14,slmax1,and sld14 slmax1mutant plants exhibited reduced plant height and increased axillary shoot proliferation compared to wild-type plants.However,these mutants showed reduced yield and delayed ripening,likely due to a source-sink imbalance caused by excessive axillary shoot development.A weak sld14 allele displayed a milder phenotype,maintaining total fruit yield and harvest index despite smaller individual fruit size.These findings indicate that allelic variation in SL-related genes can influence plant architecture and yield components.Our results suggest that weak or partial alleles may serve as promising targets for tailoring tomato architecture to space-limited cultivation systems.展开更多
Root-zone temperature(RZT)strongly affects plant growth,nutrient uptake and tolerance to environmental stress,making its regulation a key challenge in greenhouse cultivation in cold climates.This study aimed to assess...Root-zone temperature(RZT)strongly affects plant growth,nutrient uptake and tolerance to environmental stress,making its regulation a key challenge in greenhouse cultivation in cold climates.This study aimed to assess the potential of passive techniques,namely black polyethylene mulch and row covers,for modifying RZT dynamics in lettuce(Lactuca sativa L.)production and to evaluate the predictive performance of the eXtreme Gradient Boosting(XGBoost)algorithm.Experiments were conducted in Iğdır,Türkiye,over a 61-day period,with soil temperature continuously monitored at depths of 1-30 cm under mulched and non-mulched conditions,alongside measurements of greenhouse air temperature both with and without row covers.The application of row covers increased internal air temperature by 5.8℃,while mulching raised RZT by 0.6-1.3℃,with effects diminishing at deeper layers.XGBoost modeling achieved high predictive accuracy,with RMSE values of 0.150-0.189◦C and R^(2)values above 0.99,and feature-importance analysis indicated that neighboring soil depths were the strongest predictors of RZT.These findings show that integrating row covers and mulching can stabilize the root-zone microclimate without active heating.The XGBoost model provides a robust tool for forecasting soil temperature and supports sustainable greenhouse production in cold regions.展开更多
Cellular asymmetry,which represents a fundamental characteristic of cell polarity,is prominently illustrated by the apical-basal localization of PINFORMED(PIN)auxin efflux carriers in Arabidopsis thaliana.Although the...Cellular asymmetry,which represents a fundamental characteristic of cell polarity,is prominently illustrated by the apical-basal localization of PINFORMED(PIN)auxin efflux carriers in Arabidopsis thaliana.Although the maintenance of PIN polarity at the plasma membrane(PM)relies on endomembrane trafficking,the pivotal factors responsible for recruiting PIN proteins to the PM remain largely unknown.In this study,we discover that EXO70G1displays a polarized distribution at the PM in root cells.Acting as a putative subunit of the exocyst complex,which mediates the tethering of exocytic vesicles to the PM,EXO70G1 exhibits continuous recycling foci at the PM,and its dynamic behavior is akin to that of SEC6 and SEC8.Disruption of EXO70G1 and its homolog EXO70G2 in Arabidopsis reduces auxin accumulation and primary root length.Importantly,the recycling of PIN2 from the brefeldin A(BFA)compartment to the PM is compromised,and the abundance of PIN2 at the PM is reduced in the exo70G1 exo70G2 backgrounds.Interestingly,live-cell imaging reveals that the polarity of EXO70G1 is established during cytokinesis,prior to that of PIN2,and is maintained throughout the subsequent phases of cell elongation and differentiation.When the lipid raft was disturbed,the accumulation of EXO70G1 at the PM decreased.Our findings highlight the crucial role of EXO70G1 in root development by providing positional cues that facilitate the recycling efficiency of PIN2 to the PM.展开更多
The combination of Daphnes Cortex(DC)and Liquorice Root(LR),two traditional Chinese medicinal herbs,has shown significant therapeutic effects on rheumatoid arthritis(RA),but its synergistic mechanism of action remains...The combination of Daphnes Cortex(DC)and Liquorice Root(LR),two traditional Chinese medicinal herbs,has shown significant therapeutic effects on rheumatoid arthritis(RA),but its synergistic mechanism of action remains to be elucidated.Employing a network pharmacology and molecular docking approach,this study systematically investigated the synergistic mechanism of the herb pair DC and LR in RA treatment.Active components and their corresponding targets were retrieved from the TCMSP database and relevant literature,and RA-related targets were collected from established disease databases.A total of 73 overlapping targets between DC-LR and RA were identified,among which core targets such as AKT1,TNF,and CASP3 were highlighted.GO and KEGG enrichment analyses revealed that these targets are involved in biological processes such as oxidative stress response and cell migration,and are significantly enriched in key pathways including HIF-1,TNF,and PI3K-Akt signaling pathways.Compatibility analysis further revealed that the combination of DC and LR may enhance therapeutic effects through synergistic regulation of shared targets and complementary modulation of upstream and downstream pathway components.Molecular docking confirmed strong binding affinities between core active components and key targets.This study provides a multi-dimensional“component-target-pathway”perspective on the potential synergistic anti-RA mechanism of the DC-LR herb pair,offering a theoretical basis for further experimental validation and clinical application.展开更多
Root rot is a prevalent soil-borne fungal disease in citrus.Citron C-05(Citrus medica)stands out as a germplasm within Citrus spp.due to its complete resistance to citrus canker and favorable characteristics such as s...Root rot is a prevalent soil-borne fungal disease in citrus.Citron C-05(Citrus medica)stands out as a germplasm within Citrus spp.due to its complete resistance to citrus canker and favorable characteristics such as single embryo and easy rooting.However,Citron C-05 was found to be highly susceptible to root rot during cultivation,with the specific pathogens previously unknown.In this study,four candidate fungal species were isolated from Citron C-05 roots.Sequence analysis of ITS,EF-1a,RPB1,and RPB2 identified two Fusarium solani strains,Rr-2 and Rr-4,as the candidates causing root rot in Citron C-05.Resistance tests showed these two pathogens increased root damage rate from 10.30%to 35.69%in Citron C-05,sour orange(Citrus aurantium),sweet orange(Citrus sinensis)and pummelo(Citrus grandis).F.solani exhibited the weak pathogenicity towards trifoliate orange(Poncirus trifoliata).DAB staining revealed none of reddish-brown precipitation in the four susceptible citrus germplasm after infection with F.solani,while trifoliate orange exhibited significant H2O2 accumulation.Trypan blue staining indicated increased cell death in the four susceptible citrus germplasm following infection with these two pathogens but not in trifoliate orange.These findings provide a comprehensive understanding of citrus root rot and support future research on the mechanisms of root rot resistance in citrus.展开更多
Objective:To identify the root causes of typical adverse drug events through the lens of patient experiences proposing novel strategies to mitigate preventable harm.Methods:A qualitative case study leveraging in-depth...Objective:To identify the root causes of typical adverse drug events through the lens of patient experiences proposing novel strategies to mitigate preventable harm.Methods:A qualitative case study leveraging in-depth interviews with patients and families,anchored by Interactive Patient Par ticipation Theory,to analyze 4 high-severity adverse drug events(ADE)cases.Cases were purposively sampled from 8 communities in China's National Adverse Event Monitor Center(2018-2023).Semi-structured interviews explored patient perspectives,with data analyzed via thematic coding and triangulation against clinical records.Results:Five interconnected themes emerged:(1)erosion of trust,(2)communication breakdowns,(3)information asymmetry,(4)environmental inadequacies,and(5)technological alienation.Notably,75% of participants had≤high school education,and 50% used≥7 medications daily,compounding ADE risks.Conclusions:We considered elements mentioned by theory,exploring trust,communication,information,and suppor t as the root causes.In addition,we added“adaptability to new technology”as an impor tant and necessary component.It is impor tant and necessary to analyze typical adverse drug events from the perspectives of patients.展开更多
Few studies have investigated alterations in the immune cell microenvironment of the dorsal root ganglia following spinal cord injury and whether these modifications facilitate axonal regeneration.In this study,we use...Few studies have investigated alterations in the immune cell microenvironment of the dorsal root ganglia following spinal cord injury and whether these modifications facilitate axonal regeneration.In this study,we used a single-cell RNA sequencing dataset to create a comprehensive profile of the diverse cell types in the dorsal root ganglia and spinal cord of a mid-thoracic contusion injury model in cynomolgus monkeys.Cell communication analysis indicated that specific signaling events among various dorsal root ganglia cell types occur in response to spinal cord injury.Single-cell analysis using dimensionality reduction clustering identified distinct molecular signatures for nine cell types,including macrophage subpopulations,and differential gene expression profiles between dorsal root ganglia cells and spinal cord cells following spinal cord injury.The macrophage subpopulations were categorized into 11 clusters(MC0-MC10)based on differentially expressed genes,with the top 10 genes being ABCA6,RBMS3,EBF1,LAMA4,ANTXR2,LAMA2,SOX5,FOXP2,GHR,and APOD.MC0,MC1,and MC2 constituted the predominant macrophage populations.MC4,MC6,and MC9 were nearly absent in the spinal cord,but exhibited significant increases in the dorsal root ganglia post-spinal cord injury.Notably,these subpopulations possess a strong capacity for regulating axonal regeneration.The developmental progression of dorsal root ganglia macrophages after spinal cord injury was elucidated using cell trajectory and pseudo-time analyses.Genes such as EBF1(MC6 and MC9 marker),RBMS3(MC6 and MC9 marker),and ABCA6(MC6 marker)showed high expression levels in the critical pathways of macrophage function.Through ligand-receptor pair analysis,we determined that the effects of macrophages on microglia are predominantly mediated through interaction pairs(e.g.,SPP1-CD44,LAMC1-CD44,and FN1-CD44),potentially facilitating specific cellular communications within the immune microenvironment.The single-cell RNA sequencing dataset used in this study represents the first comprehensive transcriptional analysis of the dorsal root ganglia after spinal cord injury in cynomolgus monkeys,encompassing nearly all cell types within the dorsal root ganglia region.Using this dataset,we evaluated diverse subtypes of macrophages in the post-spinal cord injury dorsal root ganglia area and examined the signaling pathways that facilitate interactions among immune response-related macrophages in the dorsal root ganglia.Findings from this study provide a theoretical basis for understanding how the immune microenvironment influences the regenerative capacity of dorsal root ganglia neurons after spinal cord injury and offer novel insights into the complex processes underlying the pathobiology of spinal cord injury.展开更多
Dorsal root ganglia neurons gradually lose their axonal regeneration ability during development and aging.To explore molecules that enhance axonal regeneration,we screened growth factors with differential gene express...Dorsal root ganglia neurons gradually lose their axonal regeneration ability during development and aging.To explore molecules that enhance axonal regeneration,we screened growth factors with differential gene expression patterns in the dorsal root ganglias of young adult and aged animals following sciatic nerve injury.In young adult animals,two transforming growth factor beta-related factors,activin A and angiopoietin 2,were found to be upregulated post nerve injury.Treatment of isolated dorsal root ganglia explants and cultured dorsal root ganglia neurons of neonatal and young adult rats with recombinant activin A or angiopoietin 2 protein stimulated neurite outgrowth and axonal elongation.The administration of recombinant activin A or angiopoietin 2 protein to sciatic nerve crush-injured dorsal root ganglias also supported the growth of sensory neurons and facilitated nerve regeneration in both young adult and aged rats.Using RNA sequencing,we characterized genetic changes in dorsal root ganglia neurons following recombinant activin A or angiopoietin 2 treatment,revealing the unique mechanisms of these transforming growth factor beta-related factors.Recombinant activin A elicited changes in the gene expression of cytoskeleton-related Gper1 and activated extracellular signal-regulated kinase signaling,while angiopoietin 2 increased the expression of the transcription factor gene E2f2.Our identification of activin A and angiopoietin 2 as crucial promotional factors of axonal regeneration may guide future therapeutic strategies for the treatment of nerve injury.展开更多
Root/shoot(R/S)ratio is an important index for assessing plant health,and has received increased attention in the last decades as a sensitive indicator of plant stress induced by chemical or physical agents.The R/S ra...Root/shoot(R/S)ratio is an important index for assessing plant health,and has received increased attention in the last decades as a sensitive indicator of plant stress induced by chemical or physical agents.The R/S ratio has been discussed in the context of ecological theory and its potential importance in ecological succession,where species follow different strategies for above-ground growth for light or below-ground competition for water and nutrients.We present evidence showing the R/S ratio follows a biphasic dose–response relationship under stress,typical of hormesis.The R/S ratio in response to stress has been widely compared among species and ecological succession classes.It is constrained by a variety of factors such as ontogeny.Furthermore,the current literature lacks dose-response studies incorporating the full dose–response continuum,hence limiting scientific understanding and possible valuable application.The data presented provide an important perspective for new-generation studies that can advance current ecological understanding and improve carbon storage estimates by R/S ratio considerations.Hormetic response of the R/S ratio can have an important role in forestry for producing seedlings with desired characteristics to achieve maximum health/productivity and resilience under plantation conditions.展开更多
Microshoots of Castanea mollissima cv.＇yanshanhong＇ in vitro acquired an enhanced rooting capability with increasing numbers of subculture.In this study,we investigated the effect of successive subculture on adventi...Microshoots of Castanea mollissima cv.＇yanshanhong＇ in vitro acquired an enhanced rooting capability with increasing numbers of subculture.In this study,we investigated the effect of successive subculture on adventitious root formation in vitro by the determination of the endogenous hormone level and the enzyme activity.The levels of indoleacetic acid（IAA）,abscisic acid（ABA）,cytokinins（CTK） and gibberellic acid（GA3） were determined by high performance liquid chromatography（HPLC）,and the activities of indoleacetic acid oxidase（IAAO）,peroxidase oxidase（POD）,and polyphenol oxidase（PPO） were measured by ultraviolet-spectrophotometer assay after the induction of rooting at 2nd,4th,6th and 8th subculture.The relationships between physiological characteristics and subculture numbers or rooting rate were as follows：The levels of endogenous IAA in microshoots gradually increased,and endogenous levels of ABA,CTK and GA3 in microshoots decreased slightly after serial subcultures.The level of IAA was highly correlated with subculture numbers and rooting rates.The ratios of IAA/ABA and IAA/CTK both acutely raised with increasing rooting rate during successive subcultures and had high correlations with rooting rate.The activity of IAAO and POD are significantly negatively related with subculture numbers,and the activity of PPO increased after subcultures.展开更多
The dynamic relationship of dry matter accumulation and distribution between winter wheat root and shoot was studied under different soil water conditions. The dry matter accumulation in root was greatly influenced by...The dynamic relationship of dry matter accumulation and distribution between winter wheat root and shoot was studied under different soil water conditions. The dry matter accumulation in root was greatly influenced by water stress, so as to the final root weight of the treatment with 40% field moisture capacity(FMC) was less than 1/4 of that of the treatment with 80% FMC on average. Water stress during the 3-leaf stage to the tillering stage had the greatest influence on root, and the influence of water stress during the jointing stage to the booting stage on shoot was greater than root. However, water stress during the tillering stage to the booting stage had a balanced effect on root and shoot, and the proportion of dry matter that distributed to root and shoot was almost the same after rewatering. Water recovery during the jointing stage to booting stage could promote R/S, but the increasing degree was related to the duration of water limitation. Soil water condition had the lowest effect on R/S during the flowering stage to the filling stage and the maximal effect on R/S during the jointing stage to the heading stage, R/S of 40% FMC treatment was 20.93 and 126.09% higher than that of 60% FMC and 80% FMC treatments respectively at this period.展开更多
Tree peony is well known and sought after for its large, colorful flowers. Its propagation is via vegetative methods. Mech- nisms of the adventitious rooting and the regulation of rooting processes are the principles ...Tree peony is well known and sought after for its large, colorful flowers. Its propagation is via vegetative methods. Mech- nisms of the adventitious rooting and the regulation of rooting processes are the principles and techniques of plant propagation and improvement. Microstructures and fluctuations of phytohormones in the adventitious rooting were studied with the etiolated soft- wood shoots of Paeonia suffkuticosa ＇Yinfen Jinlin＇. There are no pre-primordia in the shoots of the cultivar. Adventitious roots are produced in five stages： shoot selection, primordium initiation, primordium growth, conducting tissue differentiation and root protru- sion. Primordia initiated in the cortex. The contents of the endogenous hormones, IAA, ABA and GA, were 5.842, 0.873 and 1.043 nmol·g^-1 FW on the bases of shoots, respectively. CTKs which included isopentenyl adenine （iPA）, zeatin riboside （ZR） and dihy- drozeatin riboside （DHZR） were 0.949, 0.695 and 2.034 nmol·g^-1 FW, respectively. DHZR is active among CTKs. The ratio of IAA to GA, CTK and ABA clearly increased at the stage of primordium initiation, while they showed low levels at the stages of primor- dium growth. The ratios were restored at the shoot levels at the stage of root protrusion. IBA provoked primordia initiation in the cortex, the vascular cambium, the pith and even in the callus induced on the base of shoots. ]AA levels in the treated shoots increased gradually to its highest level （three times of control） at the stage of conducting tissue differentiation. The ratios of IAA to GA, CTK and ABA clearly decreased at the stage of primordium initiation. The ratio of IAA to ABA is regulated at 10：1.展开更多
A study was conducted at Akron, CO, USA, on a Weld silt loam in 2004 to quantify the effects of water deficit stress on corn (Zea mays, L.) root and shoot biomass. Corn plants were grown under a range of soil bulk den...A study was conducted at Akron, CO, USA, on a Weld silt loam in 2004 to quantify the effects of water deficit stress on corn (Zea mays, L.) root and shoot biomass. Corn plants were grown under a range of soil bulk density and water conditions caused by previous tillage, crop rotation, and irrigation management. Water deficit stress (Dstress) was quantified by the number of days when the water content in the surface 0.3 m deviated from the water content range determined by the Least Limiting Water Range (LLWR). Root and shoot samples were collected at the V6, V12, and R1 growth stages. There was no significant correlation between Dstress and shoot or root biomass at the V6 growth stage. At the V12 and R1 growth stages, there were negative, linear correlations among Dstress and both root biomass and shoot biomass. The proportional decrease of shoot biomass was greater than the proportional decrease in root biomass, leading to an increase in the root:shoot ratio as water deficit stress increased at all growth stages. Determining restrictive soil conditions using the LLWR may be useful for evaluating improvement or degradation of the soil physical environment caused by soil management.展开更多
Phosphorous （P） deficiency is a major restraint factor for crop production and plants have developed several mechanisms to adapt to low P stress. In this study, a set of 271 introgression lines （ILs） were used to ...Phosphorous （P） deficiency is a major restraint factor for crop production and plants have developed several mechanisms to adapt to low P stress. In this study, a set of 271 introgression lines （ILs） were used to characterize the responses of seedlings to low P availability and to identify QTLs for root traits, biomass, and plant height under P-deficiency and P-sufficiency conditions. Plant height, total dry weight, shoot dry weight, and root number were inhibited under P-deficiency, whereas maximum root length （MRL） and root-shoot ratio （RS） were induced by P-deficiency stress. Relative MRL （RMRL, the ratio of MRL under P-deficiency to MRL under P-sufficiency con- dition） and relative RS （RRS） were used to evaluate P-deficiency tolerance at the seedling stage. A total of 24 additive QTLs and 29 pairs of epistatic QTLs were detected, but only qRN4 was detected in both conditions. This suggested that different mechanisms may exist in both P supply levels. QTLs for adaptive traits （RMRL, RRS, RRV, and RRDW） and qRN4 consistently expressed to increase trait stability may contribute to P-deficiency tolerance. Twelve intervals were cluster regions of QTLs for P-deficiency tolerance, and one QTL （qRRSS） showed pleiotropic effects on P-deficiency tolerance and drought tolerance. These interesting QTLs can be used in marker-assisted breeding through the target ILs.展开更多
Tree peony is a famous ornamental plant,while the low propagation rate is the main hurdles hindering the industry development.Till now,the highly efficient regeneration system for tree peony is not established.In this...Tree peony is a famous ornamental plant,while the low propagation rate is the main hurdles hindering the industry development.Till now,the highly efficient regeneration system for tree peony is not established.In this study,using Paeonia ostii’Fengdan’mature embryos,the effects of variations in inoculation method,initiating culture,adventitious shoot induction,rooting media,plant growth regulators(PGRs),and a nonconventional PGR(plant extracts)on regeneration from explants were evaluated.In embryo cultures,embryonic callus induction rate of 1/4 embryos was the highest among those of embryos with other three technical treatments(whole embryos,1/2 embryos,and pieces of embryos).The woody plant medium(WPM)containing 1.0 mg·L^(-1)6-BA,0.5 mg·L^(-1)GA3,30.0 g·L^(-1)sucrose,and 3.0 g·L^(-1)phytagel significantly improved shoot induction and multiplication.3.0 mg·L^(-1)plant extracts promoted hypocotyl germination,rooting,and root growth,in direct embryo culture,and a combination of 3.0 mg·L^(-1)plant extracts+2.0 mg·L^(-1)IBA+1.5 mg·L^(-1)IAA produced optimal rooting induction rate for multiple shoots in direct embryo culture and indirect somatic embryogenesis.For the three in vitro micropropagation methods,the highest shoot proliferation coefficient(5.4±0.2)was obtained with indirect somatic embryogenesis.Fortunately,the propagation ability of shoots remains high,even when culture propagation was continued for more than two years.Thus,a reliable system for plant regeneration from mature embryos derived from P.ostii’Fengdan’callus and two direct embryo culture systems have been established.The novel regeneration system could facilitate uniform seedling production.展开更多
基金supported by grant from the National Key Technology Support Program of the Ministry of Science and Technology of China(No.2021ZD0203204)。
文摘Pseudounipolar neurons in the dorsal root ganglia(DRG),as the central nodes of primary sensory afferents,possess a distinctive T-junction that is not merely a morphological peculiarity but also performs complex roles in rapid,multiplexed shunting and regulation of sensory signals.This specialized geometry enables separation,filtering,and feedback regulation of neuronal signals,thereby coordinating peripheral and central responses at multiple levels.Recent advances,including spatial transcriptomics,single-cell sequencing,super-resolution microscopy,organoid models,and novel electrophysiological methods,have permitted more precise dissection of the T-junction's molecular composition,ion-channel distribution,and electrophysiological properties.Here,we review current knowledge of the T-junction's developmental regulation and multilayered molecular networks,and we detail its functional alterations in both physiological signaling and pathological pain states,with particular emphasis on ion-channel modulation,signal attenuation,and selective transmission mechanisms.Finally,we discuss contemporary pain-intervention approaches and prospects for precision-targeted therapies,aiming to provide a theoretical foundation for future studies in pain physiology and clinical translation.
文摘背景:近年来,生物陶瓷材料因具有良好的生物相容性和封闭性能逐渐成为根尖倒充填的首选材料,其中生物陶瓷材料C-Root BP、iRoot BP Plus均具有良好的生物相容性和封闭性能。目的:对比体外环境下C-Root BP与iRoot BP Plus材料的根尖封闭性能及抗力强度。方法:于2022年6月至2024年6月期间,收集石家庄市第二医院口腔科因正畸或牙周病新鲜拔除的单根离体牙56颗,随机分4组处理:iRoot BP Plus组(n=16)、C-Root BP组(n=16)根管预备和消毒后分别采用iRoot BP Plus、C-Root BP材料进行根尖倒充填,阳性对照组(n=16)根管预备和消毒后使用蒸馏水进行根尖倒充填,阴性对照组(n=8)仅行根管预备和消毒(不进行根尖倒充填处理),采用染料渗透法检测根尖封闭性;制作根管细菌渗漏体外模型,评价细菌微渗漏发生情况;采用薄片推出实验检测填充材料与牙本质之间的粘连强度,并在显微镜下观察断裂形式。结果与结论:(1)染料染色7 d后,阳性对照组染料渗透长度大于iRoot BP Plus组、C-Root BP组(P<0.05),iRoot BP Plus组和C-Root BP组染料渗透长度比较差异无显著性意义(P>0.05);(2)经过90 d培养,阳性对照组细菌微渗漏发生率高于iRoot BP Plus组、C-Root BP组(P<0.05),iRoot BPPlus组和C-Root BP组细菌微渗漏发生率比较差异无显著性意义(P>0.05);(3)C-Root BP组填充材料与牙本质之间的粘连强度大于iRootBP Plus组(P<0.05),两组断裂面断裂形式比较差异无显著性意义(P>0.05);(4)结果表明,采用C-Root BP和iRoot BP Plus材料进行根尖倒充填可产生相似的根尖封闭效果,并且断裂形式也基本一致,但C-Root BP材料具有良好的粘连强度。
基金funded by the National Natural Science Foundation of China(32471824,32171746,31870522,42477227,and 32560282)the leading talents of basic research in Henan Province(24XM0375)+6 种基金Excellent Youth Creative Research Group Project in Henan Province(252300421002)Foreign Scientists Studio in Henan Province(GZS2025011)MOHRSS National Foreign Expert Individual Projectsand(110000264820258001)Natural Science Foundation of Henan(242300420604)supported by the Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control(2023B1212060002)the High-level University Special Fund(G03050K001)the China Postdoctoral Science Foundation(No.2021M690922).
文摘Soil compaction often imposes stress on root development and plant survival.However,root anatomical responses that enable persistent root growth and functioning under soil compaction remain unclear.We grew 10 herbaceous species differing substantially in lateral root diameter,in soils with low(1.0 g cm^(-3))and high(1.4 g cm^(-3))bulk density,and assessed root traits including root biomass,anatomical structures,and respiration rates.Greater root thickening upon soil compaction was found in species with thicker first-order lateral roots,mainly due to larger cortical cell size.Both xylem vessel diameter and wall thickness increased more in compacted soils in these species.Despite these anatomical shifts,root respiration rate responded little to soil compaction across most species,likely due to the opposite investment in cortical cells and xylem vessels.Notably,root biomass,independent of root respiration rate and anatomical structures,determined whole-plant growth under soil compaction.Our study reveals two independent strategies of root response to soil compaction:anatomical remodeling for mechanical and metabolic maintenance,and root biomass investment for resource acquisition.These findings offer new insights for breeding and selecting species tolerant to soil compaction and highlight multidimensional strategies of plant adaptation to physical stress.
基金funded by the Major Science and Technology Projects of Zhejiang Province,China(Grant No.2021C02063-5)the Key Research and Development Projects of Hainan Province,China(Grant No.ZDYF2023XDNY086)+2 种基金the State Key Laboratory for Quality and Safety Hazard Factors and Risk Prevention and Control of Agricultural Products Jointly Constructed by the Ministry and the Province,China(Grant No.2010DS700124)the Zhejiang Province Vanguard Leading Goose Project,China(Grant Nos.2023C02055 and 2022C02034)the Jiaxing Nanhu District Science and Technology Plan Project,China(Grant No.2023017).
文摘The shift from seedling transplanting to direct-seeding cultivation in rice demands robust root systems for early seedling establishment and yield stability.While the pleiotropic gene OsSP3(also designated TAC4 or SG2)is known to regulate aboveground traits,including tiller angle,grain size,and panicle development,its function in root morphogenesis remains uncharacterized.
基金supported financially by the National Key Research&Development Program of China(2021YFD1700200)the National Natural Science Foundation of China(32402686)+3 种基金the Earmarked Fund for China Agriculture Research System(CARS-22)the Fundamental Research Funds for Central Non-profit Scientific Institution,China(1610132022013)the Science and Technology Innovation Project of Chinese Academy of Agricultural Sciencesthe China National Crop Germplasm Resources Platform for Green Manure(NICGR-2024-19)。
文摘Green manuring is essential for improving soil quality and nutrient uptake.With the gradual depletion of phosphorus(P)resources,more attention is being paid to the role of green manures in cultivation systems,such as maize-green manure intercropping,to find possible pathways for enhancing soil P utilization.A maize-green manure intercropping experiment was started in 2009 to investigate the effects and mechanisms for enhancing P uptake and yield in maize.Three species of green manures(hairy vetch(HV),needle leaf pea(NP),sweet pea(SP))and a sole maize treatment(CK)were used,resulting in four treatments(CK,HVT,NPT,and SPT)in the experiment.During 2020-2023,the intercropping treatments enhanced maize yields in 2020 and 2021,particularly in HVT with increases of 13.7%(1.96 t ha^(-1))and 13.0%(2.13 t ha^(-1))compared with CK,respectively.Grain P accumulation of maize was significantly higher in the intercropping treatments than CK in 2020,2021,and 2023,and with an average increase of 10.6%over the four years(5.2% for NPT,10.8% for SPT and 15.9% for HVT)compared with CK.Intercropping promoted maize growth with a greater root length density and a higher organic acid release rate.HVT changed the soil properties more dramatically than the other treatments,with increases in the acid phosphatase and alkaline phosphatase activities of 29.8 and 38.5%,respectively,in the topsoil(0-15 cm),while the soil p H was reduced by 0.37 units compared to CK(p H=8.44).Intercropping treatments facilitated the conversion of non-labile P to mod-labile P and stimulated the growth of soil bacteria in the topsoil.Compared with CK,the relative abundance of Gemmatimonadota,known for accumulating polyphosphate,and Actinobacteriota,a prominent source of bioactive compounds,increased significantly in the intercropping treatments,especially in HVT and SPT.A PLS-PM analysis showed that intercropping promoted soil P mobilization and the enrichment of beneficial bacteria by regulating maize root morphology and physiology.Our results highlight that maize-green manure intercropping optimizes root traits,soil properties and bacterial composition,which contribute to greater maize P uptake and yield,providing an effective strategy for sustainable crop production.
基金funded by the National Research Foundation of Korea(NRF)grant from the Ministry of Science and ICT(MSIT),Republic of Korea(Nos.RS-2024-00407469 and RS-2025-00517964)the BK21 FOUR program of Graduate School,Kyung Hee University(GS-1-JO-NON-20240417)。
文摘Optimizing plant architecture for specific cultivation methods is essential for enhancing fruit productivity.Unlike indeterminate growth plants,the total productivity of determinate growth plants relies on cumulative fruit production and synchronized fruit ripening from both main and axillary shoots.Here,we focused on SlD14and SlMAX1,two key genes involved in the regulation of strigolactone(SL)signaling and biosynthesis,with the goal of maximizing yield and syn chronizing fruit ripening by fine-tuning axillary shoot growth.Using clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated protein 9(Cas9)technology,we found that the sld14,slmax1,and sld14 slmax1mutant plants exhibited reduced plant height and increased axillary shoot proliferation compared to wild-type plants.However,these mutants showed reduced yield and delayed ripening,likely due to a source-sink imbalance caused by excessive axillary shoot development.A weak sld14 allele displayed a milder phenotype,maintaining total fruit yield and harvest index despite smaller individual fruit size.These findings indicate that allelic variation in SL-related genes can influence plant architecture and yield components.Our results suggest that weak or partial alleles may serve as promising targets for tailoring tomato architecture to space-limited cultivation systems.
文摘Root-zone temperature(RZT)strongly affects plant growth,nutrient uptake and tolerance to environmental stress,making its regulation a key challenge in greenhouse cultivation in cold climates.This study aimed to assess the potential of passive techniques,namely black polyethylene mulch and row covers,for modifying RZT dynamics in lettuce(Lactuca sativa L.)production and to evaluate the predictive performance of the eXtreme Gradient Boosting(XGBoost)algorithm.Experiments were conducted in Iğdır,Türkiye,over a 61-day period,with soil temperature continuously monitored at depths of 1-30 cm under mulched and non-mulched conditions,alongside measurements of greenhouse air temperature both with and without row covers.The application of row covers increased internal air temperature by 5.8℃,while mulching raised RZT by 0.6-1.3℃,with effects diminishing at deeper layers.XGBoost modeling achieved high predictive accuracy,with RMSE values of 0.150-0.189◦C and R^(2)values above 0.99,and feature-importance analysis indicated that neighboring soil depths were the strongest predictors of RZT.These findings show that integrating row covers and mulching can stabilize the root-zone microclimate without active heating.The XGBoost model provides a robust tool for forecasting soil temperature and supports sustainable greenhouse production in cold regions.
基金supported by National Natural Science Foundation of China(31571467)Shandong Province Natural Science Foundation(ZR2021MC141)。
文摘Cellular asymmetry,which represents a fundamental characteristic of cell polarity,is prominently illustrated by the apical-basal localization of PINFORMED(PIN)auxin efflux carriers in Arabidopsis thaliana.Although the maintenance of PIN polarity at the plasma membrane(PM)relies on endomembrane trafficking,the pivotal factors responsible for recruiting PIN proteins to the PM remain largely unknown.In this study,we discover that EXO70G1displays a polarized distribution at the PM in root cells.Acting as a putative subunit of the exocyst complex,which mediates the tethering of exocytic vesicles to the PM,EXO70G1 exhibits continuous recycling foci at the PM,and its dynamic behavior is akin to that of SEC6 and SEC8.Disruption of EXO70G1 and its homolog EXO70G2 in Arabidopsis reduces auxin accumulation and primary root length.Importantly,the recycling of PIN2 from the brefeldin A(BFA)compartment to the PM is compromised,and the abundance of PIN2 at the PM is reduced in the exo70G1 exo70G2 backgrounds.Interestingly,live-cell imaging reveals that the polarity of EXO70G1 is established during cytokinesis,prior to that of PIN2,and is maintained throughout the subsequent phases of cell elongation and differentiation.When the lipid raft was disturbed,the accumulation of EXO70G1 at the PM decreased.Our findings highlight the crucial role of EXO70G1 in root development by providing positional cues that facilitate the recycling efficiency of PIN2 to the PM.
基金supported by National Training Program of Innovation and Entrepreneurship for Undergraduates(202510163044).
文摘The combination of Daphnes Cortex(DC)and Liquorice Root(LR),two traditional Chinese medicinal herbs,has shown significant therapeutic effects on rheumatoid arthritis(RA),but its synergistic mechanism of action remains to be elucidated.Employing a network pharmacology and molecular docking approach,this study systematically investigated the synergistic mechanism of the herb pair DC and LR in RA treatment.Active components and their corresponding targets were retrieved from the TCMSP database and relevant literature,and RA-related targets were collected from established disease databases.A total of 73 overlapping targets between DC-LR and RA were identified,among which core targets such as AKT1,TNF,and CASP3 were highlighted.GO and KEGG enrichment analyses revealed that these targets are involved in biological processes such as oxidative stress response and cell migration,and are significantly enriched in key pathways including HIF-1,TNF,and PI3K-Akt signaling pathways.Compatibility analysis further revealed that the combination of DC and LR may enhance therapeutic effects through synergistic regulation of shared targets and complementary modulation of upstream and downstream pathway components.Molecular docking confirmed strong binding affinities between core active components and key targets.This study provides a multi-dimensional“component-target-pathway”perspective on the potential synergistic anti-RA mechanism of the DC-LR herb pair,offering a theoretical basis for further experimental validation and clinical application.
基金supported by Joint Funds of the National Natural Science Foundation of China(Grant No.U21A20228).
文摘Root rot is a prevalent soil-borne fungal disease in citrus.Citron C-05(Citrus medica)stands out as a germplasm within Citrus spp.due to its complete resistance to citrus canker and favorable characteristics such as single embryo and easy rooting.However,Citron C-05 was found to be highly susceptible to root rot during cultivation,with the specific pathogens previously unknown.In this study,four candidate fungal species were isolated from Citron C-05 roots.Sequence analysis of ITS,EF-1a,RPB1,and RPB2 identified two Fusarium solani strains,Rr-2 and Rr-4,as the candidates causing root rot in Citron C-05.Resistance tests showed these two pathogens increased root damage rate from 10.30%to 35.69%in Citron C-05,sour orange(Citrus aurantium),sweet orange(Citrus sinensis)and pummelo(Citrus grandis).F.solani exhibited the weak pathogenicity towards trifoliate orange(Poncirus trifoliata).DAB staining revealed none of reddish-brown precipitation in the four susceptible citrus germplasm after infection with F.solani,while trifoliate orange exhibited significant H2O2 accumulation.Trypan blue staining indicated increased cell death in the four susceptible citrus germplasm following infection with these two pathogens but not in trifoliate orange.These findings provide a comprehensive understanding of citrus root rot and support future research on the mechanisms of root rot resistance in citrus.
基金supported by the Science and Technology Fund Project of Guizhou Health Commission(gzwkj2025-163)。
文摘Objective:To identify the root causes of typical adverse drug events through the lens of patient experiences proposing novel strategies to mitigate preventable harm.Methods:A qualitative case study leveraging in-depth interviews with patients and families,anchored by Interactive Patient Par ticipation Theory,to analyze 4 high-severity adverse drug events(ADE)cases.Cases were purposively sampled from 8 communities in China's National Adverse Event Monitor Center(2018-2023).Semi-structured interviews explored patient perspectives,with data analyzed via thematic coding and triangulation against clinical records.Results:Five interconnected themes emerged:(1)erosion of trust,(2)communication breakdowns,(3)information asymmetry,(4)environmental inadequacies,and(5)technological alienation.Notably,75% of participants had≤high school education,and 50% used≥7 medications daily,compounding ADE risks.Conclusions:We considered elements mentioned by theory,exploring trust,communication,information,and suppor t as the root causes.In addition,we added“adaptability to new technology”as an impor tant and necessary component.It is impor tant and necessary to analyze typical adverse drug events from the perspectives of patients.
基金supported by the Tianjin Key Medical Discipline(Specialty)Construct Project,No.TJYXZDXK-027A(to SF)the National Key Research andDevelopment Project of Stem Cell and Transformation Research,No.2019YFA0112100(to SF)+2 种基金Tianjin Natural Science Foundation’s Youth Project for DiverseInvestments,No.21JCQNJC01300(to BF)the National Natural Science Foundation of China(Youth Program),No.82102563(to BF)Tianjin Major Science andTechnology Special Projects and Engineering Projects,No.21ZXJBSY00080(to YR).
文摘Few studies have investigated alterations in the immune cell microenvironment of the dorsal root ganglia following spinal cord injury and whether these modifications facilitate axonal regeneration.In this study,we used a single-cell RNA sequencing dataset to create a comprehensive profile of the diverse cell types in the dorsal root ganglia and spinal cord of a mid-thoracic contusion injury model in cynomolgus monkeys.Cell communication analysis indicated that specific signaling events among various dorsal root ganglia cell types occur in response to spinal cord injury.Single-cell analysis using dimensionality reduction clustering identified distinct molecular signatures for nine cell types,including macrophage subpopulations,and differential gene expression profiles between dorsal root ganglia cells and spinal cord cells following spinal cord injury.The macrophage subpopulations were categorized into 11 clusters(MC0-MC10)based on differentially expressed genes,with the top 10 genes being ABCA6,RBMS3,EBF1,LAMA4,ANTXR2,LAMA2,SOX5,FOXP2,GHR,and APOD.MC0,MC1,and MC2 constituted the predominant macrophage populations.MC4,MC6,and MC9 were nearly absent in the spinal cord,but exhibited significant increases in the dorsal root ganglia post-spinal cord injury.Notably,these subpopulations possess a strong capacity for regulating axonal regeneration.The developmental progression of dorsal root ganglia macrophages after spinal cord injury was elucidated using cell trajectory and pseudo-time analyses.Genes such as EBF1(MC6 and MC9 marker),RBMS3(MC6 and MC9 marker),and ABCA6(MC6 marker)showed high expression levels in the critical pathways of macrophage function.Through ligand-receptor pair analysis,we determined that the effects of macrophages on microglia are predominantly mediated through interaction pairs(e.g.,SPP1-CD44,LAMC1-CD44,and FN1-CD44),potentially facilitating specific cellular communications within the immune microenvironment.The single-cell RNA sequencing dataset used in this study represents the first comprehensive transcriptional analysis of the dorsal root ganglia after spinal cord injury in cynomolgus monkeys,encompassing nearly all cell types within the dorsal root ganglia region.Using this dataset,we evaluated diverse subtypes of macrophages in the post-spinal cord injury dorsal root ganglia area and examined the signaling pathways that facilitate interactions among immune response-related macrophages in the dorsal root ganglia.Findings from this study provide a theoretical basis for understanding how the immune microenvironment influences the regenerative capacity of dorsal root ganglia neurons after spinal cord injury and offer novel insights into the complex processes underlying the pathobiology of spinal cord injury.
基金supported by Major Program of National Natural Science Foundation of China,No.92368207Frontier Leading Technology BasicResearch Major Project of Jiangsu Province,No.BK20232023(both to XG).
文摘Dorsal root ganglia neurons gradually lose their axonal regeneration ability during development and aging.To explore molecules that enhance axonal regeneration,we screened growth factors with differential gene expression patterns in the dorsal root ganglias of young adult and aged animals following sciatic nerve injury.In young adult animals,two transforming growth factor beta-related factors,activin A and angiopoietin 2,were found to be upregulated post nerve injury.Treatment of isolated dorsal root ganglia explants and cultured dorsal root ganglia neurons of neonatal and young adult rats with recombinant activin A or angiopoietin 2 protein stimulated neurite outgrowth and axonal elongation.The administration of recombinant activin A or angiopoietin 2 protein to sciatic nerve crush-injured dorsal root ganglias also supported the growth of sensory neurons and facilitated nerve regeneration in both young adult and aged rats.Using RNA sequencing,we characterized genetic changes in dorsal root ganglia neurons following recombinant activin A or angiopoietin 2 treatment,revealing the unique mechanisms of these transforming growth factor beta-related factors.Recombinant activin A elicited changes in the gene expression of cytoskeleton-related Gper1 and activated extracellular signal-regulated kinase signaling,while angiopoietin 2 increased the expression of the transcription factor gene E2f2.Our identification of activin A and angiopoietin 2 as crucial promotional factors of axonal regeneration may guide future therapeutic strategies for the treatment of nerve injury.
基金supported by JSPS KAKENHI Grant Number JP17F17102German Research Foundation(BE4189/1-3)+1 种基金the US Air Force[AFOSR FA9550-13-1-0047]Exxon Mobil Foundation[S18200000000256]
文摘Root/shoot(R/S)ratio is an important index for assessing plant health,and has received increased attention in the last decades as a sensitive indicator of plant stress induced by chemical or physical agents.The R/S ratio has been discussed in the context of ecological theory and its potential importance in ecological succession,where species follow different strategies for above-ground growth for light or below-ground competition for water and nutrients.We present evidence showing the R/S ratio follows a biphasic dose–response relationship under stress,typical of hormesis.The R/S ratio in response to stress has been widely compared among species and ecological succession classes.It is constrained by a variety of factors such as ontogeny.Furthermore,the current literature lacks dose-response studies incorporating the full dose–response continuum,hence limiting scientific understanding and possible valuable application.The data presented provide an important perspective for new-generation studies that can advance current ecological understanding and improve carbon storage estimates by R/S ratio considerations.Hormetic response of the R/S ratio can have an important role in forestry for producing seedlings with desired characteristics to achieve maximum health/productivity and resilience under plantation conditions.
基金supported by Special Scientific Research Fund for Doctor Subjects of Universities(NO20060022010)China National key Tech R&D Program (No2006BAD18B0202)
文摘Microshoots of Castanea mollissima cv.＇yanshanhong＇ in vitro acquired an enhanced rooting capability with increasing numbers of subculture.In this study,we investigated the effect of successive subculture on adventitious root formation in vitro by the determination of the endogenous hormone level and the enzyme activity.The levels of indoleacetic acid（IAA）,abscisic acid（ABA）,cytokinins（CTK） and gibberellic acid（GA3） were determined by high performance liquid chromatography（HPLC）,and the activities of indoleacetic acid oxidase（IAAO）,peroxidase oxidase（POD）,and polyphenol oxidase（PPO） were measured by ultraviolet-spectrophotometer assay after the induction of rooting at 2nd,4th,6th and 8th subculture.The relationships between physiological characteristics and subculture numbers or rooting rate were as follows：The levels of endogenous IAA in microshoots gradually increased,and endogenous levels of ABA,CTK and GA3 in microshoots decreased slightly after serial subcultures.The level of IAA was highly correlated with subculture numbers and rooting rates.The ratios of IAA/ABA and IAA/CTK both acutely raised with increasing rooting rate during successive subcultures and had high correlations with rooting rate.The activity of IAAO and POD are significantly negatively related with subculture numbers,and the activity of PPO increased after subcultures.
基金supported by the National Natural Science Foundation of China(49971042).
文摘The dynamic relationship of dry matter accumulation and distribution between winter wheat root and shoot was studied under different soil water conditions. The dry matter accumulation in root was greatly influenced by water stress, so as to the final root weight of the treatment with 40% field moisture capacity(FMC) was less than 1/4 of that of the treatment with 80% FMC on average. Water stress during the 3-leaf stage to the tillering stage had the greatest influence on root, and the influence of water stress during the jointing stage to the booting stage on shoot was greater than root. However, water stress during the tillering stage to the booting stage had a balanced effect on root and shoot, and the proportion of dry matter that distributed to root and shoot was almost the same after rewatering. Water recovery during the jointing stage to booting stage could promote R/S, but the increasing degree was related to the duration of water limitation. Soil water condition had the lowest effect on R/S during the flowering stage to the filling stage and the maximal effect on R/S during the jointing stage to the heading stage, R/S of 40% FMC treatment was 20.93 and 126.09% higher than that of 60% FMC and 80% FMC treatments respectively at this period.
文摘Tree peony is well known and sought after for its large, colorful flowers. Its propagation is via vegetative methods. Mech- nisms of the adventitious rooting and the regulation of rooting processes are the principles and techniques of plant propagation and improvement. Microstructures and fluctuations of phytohormones in the adventitious rooting were studied with the etiolated soft- wood shoots of Paeonia suffkuticosa ＇Yinfen Jinlin＇. There are no pre-primordia in the shoots of the cultivar. Adventitious roots are produced in five stages： shoot selection, primordium initiation, primordium growth, conducting tissue differentiation and root protru- sion. Primordia initiated in the cortex. The contents of the endogenous hormones, IAA, ABA and GA, were 5.842, 0.873 and 1.043 nmol·g^-1 FW on the bases of shoots, respectively. CTKs which included isopentenyl adenine （iPA）, zeatin riboside （ZR） and dihy- drozeatin riboside （DHZR） were 0.949, 0.695 and 2.034 nmol·g^-1 FW, respectively. DHZR is active among CTKs. The ratio of IAA to GA, CTK and ABA clearly increased at the stage of primordium initiation, while they showed low levels at the stages of primor- dium growth. The ratios were restored at the shoot levels at the stage of root protrusion. IBA provoked primordia initiation in the cortex, the vascular cambium, the pith and even in the callus induced on the base of shoots. ]AA levels in the treated shoots increased gradually to its highest level （three times of control） at the stage of conducting tissue differentiation. The ratios of IAA to GA, CTK and ABA clearly decreased at the stage of primordium initiation. The ratio of IAA to ABA is regulated at 10：1.
文摘A study was conducted at Akron, CO, USA, on a Weld silt loam in 2004 to quantify the effects of water deficit stress on corn (Zea mays, L.) root and shoot biomass. Corn plants were grown under a range of soil bulk density and water conditions caused by previous tillage, crop rotation, and irrigation management. Water deficit stress (Dstress) was quantified by the number of days when the water content in the surface 0.3 m deviated from the water content range determined by the Least Limiting Water Range (LLWR). Root and shoot samples were collected at the V6, V12, and R1 growth stages. There was no significant correlation between Dstress and shoot or root biomass at the V6 growth stage. At the V12 and R1 growth stages, there were negative, linear correlations among Dstress and both root biomass and shoot biomass. The proportional decrease of shoot biomass was greater than the proportional decrease in root biomass, leading to an increase in the root:shoot ratio as water deficit stress increased at all growth stages. Determining restrictive soil conditions using the LLWR may be useful for evaluating improvement or degradation of the soil physical environment caused by soil management.
基金supported by the Hi-Tech Research and Development Program of China (No. 2006AA10Z158 and No. 2006AA100101)the "948" Project (No. 2006-G1)+1 种基金China National Key Technologies R & D Program (No. 2006BAD13B01-6)the Program for Chang Jiang Scholars and Innovative Research Team in University, Program of Introducing Talents of Discipline to Universi-ties in China (111-2-03).
文摘Phosphorous （P） deficiency is a major restraint factor for crop production and plants have developed several mechanisms to adapt to low P stress. In this study, a set of 271 introgression lines （ILs） were used to characterize the responses of seedlings to low P availability and to identify QTLs for root traits, biomass, and plant height under P-deficiency and P-sufficiency conditions. Plant height, total dry weight, shoot dry weight, and root number were inhibited under P-deficiency, whereas maximum root length （MRL） and root-shoot ratio （RS） were induced by P-deficiency stress. Relative MRL （RMRL, the ratio of MRL under P-deficiency to MRL under P-sufficiency con- dition） and relative RS （RRS） were used to evaluate P-deficiency tolerance at the seedling stage. A total of 24 additive QTLs and 29 pairs of epistatic QTLs were detected, but only qRN4 was detected in both conditions. This suggested that different mechanisms may exist in both P supply levels. QTLs for adaptive traits （RMRL, RRS, RRV, and RRDW） and qRN4 consistently expressed to increase trait stability may contribute to P-deficiency tolerance. Twelve intervals were cluster regions of QTLs for P-deficiency tolerance, and one QTL （qRRSS） showed pleiotropic effects on P-deficiency tolerance and drought tolerance. These interesting QTLs can be used in marker-assisted breeding through the target ILs.
基金supported by National Key R&D Program of China (Grant No.2019YFD1001500)China Agriculture Research System (Grant No.CARS-21)+1 种基金the National Natural Science Foundation of China (Grant Nos.31972440,31972455)the Agricultural Science and Technology Innovation Program (ASTIP)of the Chinese Academy of Agricultural Sciences (Grant No.CAASASTIPIVFCAAS)。
文摘Tree peony is a famous ornamental plant,while the low propagation rate is the main hurdles hindering the industry development.Till now,the highly efficient regeneration system for tree peony is not established.In this study,using Paeonia ostii’Fengdan’mature embryos,the effects of variations in inoculation method,initiating culture,adventitious shoot induction,rooting media,plant growth regulators(PGRs),and a nonconventional PGR(plant extracts)on regeneration from explants were evaluated.In embryo cultures,embryonic callus induction rate of 1/4 embryos was the highest among those of embryos with other three technical treatments(whole embryos,1/2 embryos,and pieces of embryos).The woody plant medium(WPM)containing 1.0 mg·L^(-1)6-BA,0.5 mg·L^(-1)GA3,30.0 g·L^(-1)sucrose,and 3.0 g·L^(-1)phytagel significantly improved shoot induction and multiplication.3.0 mg·L^(-1)plant extracts promoted hypocotyl germination,rooting,and root growth,in direct embryo culture,and a combination of 3.0 mg·L^(-1)plant extracts+2.0 mg·L^(-1)IBA+1.5 mg·L^(-1)IAA produced optimal rooting induction rate for multiple shoots in direct embryo culture and indirect somatic embryogenesis.For the three in vitro micropropagation methods,the highest shoot proliferation coefficient(5.4±0.2)was obtained with indirect somatic embryogenesis.Fortunately,the propagation ability of shoots remains high,even when culture propagation was continued for more than two years.Thus,a reliable system for plant regeneration from mature embryos derived from P.ostii’Fengdan’callus and two direct embryo culture systems have been established.The novel regeneration system could facilitate uniform seedling production.
