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Plants frequently encounter wounding and have evolved an extraordinary regenerative capacity to heal the wounds. However, the wound signal that triggers regenerative responses has not been identified. Here, through characterization of a tomato mutant defective in both wound-induced defense and regeneration, we demonstrate that in tomato, a plant elicitor peptide (Pep), REGENERATION FACTOR1 (REF1), acts as a systemin-independent local wound signal that primarily regulates local defense responses and regenerative responses in response to wounding. We further identified PEPR1/2 ORTHOLOG RECEPTOR-LIKE KINASE1 (PORK1) as the receptor perceiving REF1 signal for plant regeneration. REF1-PORK1-mediated signaling promotes regeneration via activating WOUND-INDUCED DEDIFFERENTIATION 1 (WIND1), a master regulator of wound-induced cellular reprogramming in plants. Thus, REF1-PORK1 signaling represents a conserved phytocytokine pathway to initiate, amplify, and stabilize a signaling cascade that orchestrates wound-triggered organ regeneration. Application of REF1 provides a simple method to boost the regeneration and transformation efficiency of recalcitrant crops.
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Proteínas de Plantas , Regeneración , Transducción de Señal , Solanum lycopersicum , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Solanum lycopersicum/metabolismo , Regulación de la Expresión Génica de las Plantas , Péptidos/metabolismoRESUMEN
Crop improvement by genome editing involves the targeted alteration of genes to improve plant traits, such as stress tolerance, disease resistance or nutritional content. Techniques for the targeted modification of genomes have evolved from generating random mutations to precise base substitutions, followed by insertions, substitutions and deletions of small DNA fragments, and are finally starting to achieve precision manipulation of large DNA segments. Recent developments in base editing, prime editing and other CRISPR-associated systems have laid a solid technological foundation to enable plant basic research and precise molecular breeding. In this Review, we systematically outline the technological principles underlying precise and targeted genome-modification methods. We also review methods for the delivery of genome-editing reagents in plants and outline emerging crop-breeding strategies based on targeted genome modification. Finally, we consider potential future developments in precise genome-editing technologies, delivery methods and crop-breeding approaches, as well as regulatory policies for genome-editing products.
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Sistemas CRISPR-Cas , Productos Agrícolas , Edición Génica , Genoma de Planta , Fitomejoramiento , Edición Génica/métodos , Fitomejoramiento/métodos , Productos Agrícolas/genética , Plantas Modificadas Genéticamente/genéticaRESUMEN
Superconductivity was discovered in (InSe2)xNbSe2. The materials are crystallized in a unique layered structure where bonded InSe2 layers are intercalated into the van der Waals gaps of 2H-phase NbSe2. The (InSe2)0.12NbSe2 superconductor exhibits a superconducting transition at 11.6 K and critical current density of 8.2 × 105 A/cm2. Both values are the highest among all transition metal dichalcogenide superconductors at ambient pressure. The present finding provides an ideal material platform for further investigation of superconducting-related phenomena in transition metal dichalcogenides.
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Recently, coupling the conventional low Pt-group-metal (low-PGM, LP) and emerging PGM-free (PF) moiety to form a composite LP/PF catalyst is proposed to be an advanced strategy to improve the intrinsic activity and stability of oxygen reduction reaction (ORR) catalysts. Milestones in terms of ORR mass activity are created by this type of catalyst. However, the specific synergy between LP and PF moieties has not been well elucidated. Herein, two model catalysts are synthesized, i.e., atomically dispersed Co/N/C supporting Pt single atoms (Co/N/C@Pt-SAs) and PtCo nanoparticles (Co/N/C@PtCo-NPs). Interestingly, the Co/N/C@PtCo-NPs catalyst presents higher ORR mass activity prior to Co/N/C@Pt-SAs. This is theoretically due to the dual "built-in electric field" in Co/N/C@PtCo-NPs: one electric field with a direction from Pt to Co in NPs and another from Pt to Co/N/C; that is, Pt gains higher electron density in Co/N/C@PtCo-NPs than that in Co/N/C@Pt-SAs, thus forming an asymmetric electron cloud, and regulating the adsorption and activation of oxygen-containing species. In addition, the existence of Co significantly decreases the average valence state of PtCo NPs, indicating a stronger affinity between PtCo NPs and Co/N/C substrate, to account for the enhanced stability.
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We present an on-chip passive pump-rejection filter on an integrated silicon carbide (SiC)-on-insulator photonic platform. Our filters exploit the optical absorption from an amorphous silicon (α-Si) thin-film layer deposited on the top surface and on the sidewalls of the SiC waveguide to reject light with a wavelength below 1.0â µm. The filter has a simple design and can be readily fabricated using a standard semiconductor wafer fabrication process and can be integrated as a pump-rejection filter component for SiC-based nonlinear and quantum photonic chips. We experimentally demonstrate a pump-rejection efficiency exceeding 230â dB/mm for 780â nm wavelengths, while we extract an insertion loss of â¼1â dB for the O-, C-, and L-bands.
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Gene innovation plays an essential role in trait evolution. Rhizobial symbioses, the most important N2-fixing agent in agricultural systems that exists mainly in Leguminosae, is one of the most attractive evolution events. However, the gene innovations underlying Leguminosae root nodule symbiosis (RNS) remain largely unknown. Here, we investigated the gene gain event in Leguminosae RNS evolution through comprehensive phylogenomic analyses. We revealed that Leguminosae-gain genes were acquired by gene duplication and underwent a strong purifying selection. Kyoto Encyclopedia of Genes and Genomes analyses showed that the innovated genes were enriched in flavonoid biosynthesis pathways, particular downstream of chalcone synthase (CHS). Among them, Leguminosae-gain type â ¡ chalcone isomerase (CHI) could be further divided into CHI1A and CHI1B clades, which resulted from the products of tandem duplication. Furthermore, the duplicated CHI genes exhibited exon-intron structural divergences evolved through exon/intron gain/loss and insertion/deletion. Knocking down CHI1B significantly reduced nodulation in Glycine max (soybean) and Medicago truncatula; whereas, knocking down its duplication gene CHI1A had no effect on nodulation. Therefore, Leguminosae-gain type â ¡ CHI participated in RNS and the duplicated CHI1A and CHI1B genes exhibited RNS functional divergence. This study provides functional insights into Leguminosae-gain genetic innovation and sub-functionalization after gene duplication that contribute to the evolution and adaptation of RNS in Leguminosae.
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Ammonia, a pivotal chemical feedstock and a potential hydrogen energy carrier, demands efficient synthesis as a key step in its utilization. The traditional Haber-Bosch process, known for its high energy consumption, has spurred researchers to seek ammonia synthesis under milder conditions. Advances in surface science and characterization technologies have deepened our understanding of the microscopic reaction mechanisms of ammonia synthesis. This article concentrates on gas-solid phase ammonia synthesis, initially exploring the latest breakthroughs and improvements in thermal catalytic synthesis. Building on this, it especially focuses on emerging external field-driven alternatives, such as photocatalysis, photothermal catalysis, and low-temperature plasma catalysis strategies. The paper concludes by discussing the future prospects and objectives of nitrogen fixation technologies. This comprehensive review is intended to provide profound insights for overcoming the inherent thermodynamic and kinetic constraints in traditional ammonia synthesis, thereby fostering a shift towards "green ammonia" production and significantly reducing the energy footprint.
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Multiplexed analysis of biomarkers in a single sample tube is essential for accurate diagnosis and therapy of diseases. However, the existing detection platforms suffer from many drawbacks, such as low specificity, limited applicable sceneries, and complicated operation. Hence, it is highly important to develop a versatile biomarker detection platform that can be used for disease diagnosis and pathophysiological research. In this study, we provide a versatile method for detecting biomarkers using dual-loop probes and quantum dots (QDs). This approach utilizes a dual-loop probe that consists of a recognition module for identifying specific targets, a template recognition module for initiating subsequent chain replacement cycles, and a signal module for facilitating the fixation of QDs on the 96-well plate. The lower limit of detection for miRNA-21 is determined to be at the aM level. Furthermore, this design may be easily expanded to simultaneously detect several targets, such as miRNA and C-reactive protein. The experimental results demonstrated the successful construction of the versatile biomarkers detection platform, and indicated that the sensitive and versatile platform has significant potential in the areas of bio-sensing, clinical diagnostics, and environmental sample analysis.
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Biomarcadores , Límite de Detección , MicroARNs , Puntos Cuánticos , Puntos Cuánticos/química , MicroARNs/análisis , Biomarcadores/análisis , Humanos , Proteína C-Reactiva/análisis , Técnicas Biosensibles/métodosRESUMEN
BACKGROUND: Previous studies have found that matrine (MAT) effectively treated Ulcerative Colitis (UC). The purpose of this study is to explore its mechanism based on the HMGB1/NLRP3/Caspase-1 signaling pathway. METHODS: MAT was administered intragastrically to DSS-induced UC mice for 14 days. The Disease Activity Index (DAI) and histological staining were measured to detect histopathological changes in colon. The levels of IL-1ß, IL-6, and TNF-α in serum were measured by ELISA. The protein and mRNA expression of HMGB1/NLRP3/Caspase-1 in the colon were detected by immunohistochemistry, western Blotting or qRT-PCR. RESULTS: MAT improved the histological pathological changes of UC mice, as assessed by DAI, colonic length, and colonic mucosal injury. MAT also reduced colonic inflammatory damage by reducing the serum IL-1ß, IL-6, and TNF-α content and decreasing the expression of HMGB1, NLRP3, Caspase-1, and IL-1ß and proteins and mRNA in the colon. CONCLUSION: MAT could significantly alleviate DSS-induced UC symptoms by reducing the expressions of pro-inflammatory cytokines, such as IL-1ß, TNF-α, and IL-6, the mechanism of which is related to the inhibition of HMGB1/NLRP3/Caspase-1 signaling pathway.
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To study the effects of light color on sea urchin (Tripneustes gratilla), blue light (B, λ450nm), yellow light (Y, λ585-590nm), red light (R, λ640nm), green light (G, λ510nm), white light (W, λ400-780nm), and darkness (H) groups were established in a recirculating seawater aquaculture system. Six different LED light color treatment groups with a photoperiod of 12 L:12 D were tested for 30 days to investigate the effects of different light colors on the feeding, growth, and enzyme activities of T. gratilla (142.45 ± 4.36 g). We found that using different LED light colors caused significantly different impacts on the feeding, growth, and enzyme activity of T. gratilla. Notably, the sea urchins in group B exhibited better growth, with a weight gain rate of 39.26%, while those in group R demonstrated poorer growth, with a weight gain rate of only 26%. The feeding status differed significantly (p < 0.05) between groups B and R, with group B consuming the highest daily intake (6.03 ± 1.69 g) and group R consuming the lowest (4.54 ± 1.26 g). Throughout the three phases, there was no significant change in the viability of the α-amylase (p > 0.05). Conversely, the pepsin viability significantly increased (p < 0.05) in group B. The lipase viability consistently remained at the lowest level, with no notable differences between group W and group B. In group R, both the α-amylase and pepsin viabilities remained lower, whereas the lipase viability was noticeably greater in each phase than in group B (p < 0.05). Among the antioxidant enzymes, group R exhibited a trend of initial increase followed by decreases in catalase, superoxide dismutase, and glutathione peroxidase activities, particularly during the third stage (15-30 days), during which a significant decrease in antioxidant enzyme activity was observed (p < 0.05). Taken together, these findings suggest that blue light positively affects the growth, feeding, digestion, and antioxidant capacity of T. gratilla in comparison with those in other light environments, whereas red light had an inhibitory effect. Furthermore, T. gratilla is a benthic organism that lives on shallow sandy sea beds. Thus, as short wavelengths of blue and green light are more widely distributed on the seafloor, and long wavelengths of red light are more severely attenuated on the seafloor, shorter wavelengths of light promote the growth of bait organisms of sea urchins, which provide better habitats for T. gratilla.
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Purpose: This study aimed to investigate the risk factors of prognosis and hemorrhagic transformation after mechanical thrombectomy (MT) in patients with posterior circulation acute ischemic stroke (PC-AIS) caused by large vessel occlusion. We sought to develop a nomogram for predicting the risk of poor prognosis and symptomatic intracerebral hemorrhage (sICH) in patients with PC-AIS. Methods: A retrospective analysis was conducted on 81 patients with PC-AIS who underwent MT treatment. We collected clinical information from the patients to assessed sICH and prognosis based on CT results and National Institutes of Health Stroke Scale (NIHSS) scores. Subsequently, they were followed up for 3 months, and their prognosis was assessed using the Modified Rankin Scale. We used the least absolute shrinkage and selection operator (LASSO) and multivariate logistic regression to determine the factors affecting prognosis to construct a nomogram. The nomogram's performance was assessed through receiver operating characteristic curves, calibration curves, decision curve analysis, and clinical impact curves. Results: Among the 81 patients with PC-AIS, 33 had a good prognosis, 48 had a poor prognosis, 19 presented with sICH, and 62 did not present with sICH. The results of the LASSO regression indicated that variables, including HPT, baseline NIHSS score, peak SBP, SBP CV, SBP SD, peak SBP, DBP CV, HbA1c, and BG SD, were predictors of patient prognosis. Variables such as AF, peak SBP, and peak DBP predicted the risk of sICH. Multivariate logistic regression revealed that baseline NIHSS score (OR = 1.115, 95% CI 1.002-1.184), peak SBP (OR = 1.060, 95% CI 1.012-1.111), SBP CV (OR = 1.296, 95% CI 1.036-1.621) and HbA1c (OR = 3.139, 95% CI 1.491-6.609) were independent risk factors for prognosis. AF (OR = 6.823, 95% CI 1.606-28.993), peak SBP (OR = 1.058, 95% CI 1.013-1.105), and peak DBP (OR = 1.160, 95% CI 1.036-1.298) were associated with the risk of sICH. In the following step, nomograms were developed, demonstrating good discrimination, calibration, and clinical applicability. Conclusion: We constructed nomograms to predict poor prognosis and risk of sICH in patients with PC-AIS undergoing MT. The model exhibited good discrimination, calibration, and clinical applicability.
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Background: Early studies have revealed antagonistic effects associated with stacking chemotherapy (CT) and endocrine therapy (ET), thereby conventional wisdom does not advocate the simultaneous combination of these two treatment modalities. Limited clinical studies exist on the combined use of neoadjuvant CT (NACT) and neoadjuvant ET (NET), and there are no reported instances of concurrent neoadjuvant treatment for locally advanced breast cancer (LABC) using capecitabine and fulvestrant (FUL). Case presentation: We reported a 54-year-old woman who was diagnosed with hormone receptor-positive (HR+) LABC at our hospital. After neoadjuvant treatment involving two distinct CT regimens did not lead to tumor regression. Consequently, the patient was transitioned to concurrent capecitabine and FUL therapy. This change resulted in favorable pathological remission without any significant adverse events during treatment. Conclusions: A novel approach involving concurrent neoadjuvant therapy with CT and endocrine therapy may offer a potentially effective treatment avenue for some cases with HR+ LABC.
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Neoplasias de la Mama , Femenino , Humanos , Persona de Mediana Edad , Neoplasias de la Mama/patología , Terapia Neoadyuvante/métodos , Capecitabina/uso terapéutico , Fulvestrant/uso terapéutico , Resultado del TratamientoRESUMEN
Nonhealing infectious wounds, characterized by bacterial colonization, wound microenvironment destruction, and shape complexity, present an intractable problem in clinical practice. Inspired by LEGOs, building-block toys that can be assembled into desired shapes, we proposed the use of electrospray nano-micro composite sodium alginate (SA) microspheres with antibacterial and angiogenic properties to fill irregularly shaped wounds instantly. Specifically, porous poly(lactic-co-glycolic acid) (PLGA) microspheres (MSs) encapsulating basic fibroblast growth factor (bFGF) were produced by a water-in-oil-in-water double-emulsion method. Then, bFGF@MSs were blended with the SA solution containing ZIF-8 nanoparticles. The resultant solution was electrosprayed to obtain nano-micro composite microspheres (bFGF@MS/ZIF-8@SAMSs). The composite MSs' size could be regulated by PLGA MS mass proportion and electrospray voltage. Moreover, bFGF, a potent angiogenic agent, and ZIF-8, bactericidal nanoparticles, were found to release from bFGF@MS/ZIF-8@SAMSs in a controlled and sustainable manner, which promoted cell proliferation, migration, and tube formation and killed bacteria. Through experimentation on rat models, bFGF@MS/ZIF-8@SAMSs were revealed to adapt to wound shapes and accelerate infected wound healing because of the synergistic effects of antibacterial and angiogenic abilities. In summation, this study developed a feasible approach to prepare bioactive nano-micro MSs as building blocks that can fill irregularly shaped infected wounds and improve healing.
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Alginatos , Antibacterianos , Factor 2 de Crecimiento de Fibroblastos , Microesferas , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Cicatrización de Heridas , Alginatos/química , Antibacterianos/química , Antibacterianos/farmacología , Cicatrización de Heridas/efectos de los fármacos , Animales , Ratas , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/farmacología , Factor 2 de Crecimiento de Fibroblastos/química , Factor 2 de Crecimiento de Fibroblastos/farmacología , Humanos , Ratas Sprague-Dawley , Staphylococcus aureus/efectos de los fármacos , Masculino , Escherichia coli/efectos de los fármacos , Neovascularización Fisiológica/efectos de los fármacos , Ácidos Hexurónicos/química , Ácidos Hexurónicos/farmacología , Células Endoteliales de la Vena Umbilical Humana , Pruebas de Sensibilidad Microbiana , Proliferación Celular/efectos de los fármacos , Ácido Glucurónico/química , Ácido Glucurónico/farmacologíaRESUMEN
Molecular engineering of drug delivering platforms to provide collaborative biological effects with loaded drugs is of great medical significance. Herein, cannabinoid receptor 1 (CB1)- and reactive oxygen species (ROS)-targeting electrosprayed microspheres (MSs) are fabricated by loading with the CB1 agonist arachidonoyl 2'-chloroethylamide (ACEA) and producing ROS in a photoresponsive manner. The synergistic anti-tumor effects of ACEA and ROS released from the MSs are assessed. ACEA inhibits epidermal growth factor receptor signaling and altered tumor microenvironment (TME) by activating CB1 to induce tumor cell death. The MSs are composed of glycidyl methacrylate-conjugated xanthan gum (XGMA) and Fe3+, which form dual molecular networks based on a Fe3+-(COO-)3 network and a CâC addition reaction network. Interestingly, the Fe3+-(COO-)3 network can be disassembled instantly under the conditions of lactate sodium and ultraviolet exposure, and the disassembly is accompanied by massive ROS production, which directly injures tumor cells. Meanwhile, the transition of dual networks to a single network boosts the ACEA release. Together, the activities of the ACEA and MSs promote immunogenic tumor cell death and create a tumor-suppressive TME by increasing M1-like tumor-associated macrophages and CD8+ T cells. In summation, this study demonstrates strong prospects of improving anti-tumor effects of drug delivering platforms through molecular design.
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Antineoplásicos , Ácidos Araquidónicos , Agonistas de Receptores de Cannabinoides , Neoplasias Colorrectales , Inmunoterapia , Receptor Cannabinoide CB1 , Microambiente Tumoral , Hidrogeles/administración & dosificación , Microesferas , Inmunoterapia/métodos , Receptor Cannabinoide CB1/agonistas , Especies Reactivas de Oxígeno/metabolismo , Agonistas de Receptores de Cannabinoides/administración & dosificación , Agonistas de Receptores de Cannabinoides/farmacología , Antineoplásicos/administración & dosificación , Antineoplásicos/farmacología , Receptores ErbB/antagonistas & inhibidores , Microambiente Tumoral/efectos de los fármacos , Microambiente Tumoral/inmunología , Macrófagos Asociados a Tumores/efectos de los fármacos , Macrófagos Asociados a Tumores/inmunología , Linfocitos T CD8-positivos/efectos de los fármacos , Linfocitos T CD8-positivos/inmunología , Sistemas de Liberación de Medicamentos , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/inmunología , Humanos , Línea Celular Tumoral , Rayos Ultravioleta , Ácidos Araquidónicos/administración & dosificación , Ácidos Araquidónicos/farmacología , Polisacáridos Bacterianos/química , Compuestos Epoxi/química , Metacrilatos/química , Diseño de FármacosRESUMEN
Lipocalin 2 (LCN2) is a secreted glycoprotein that is produced by immune cells, including neutrophils and macrophages. It serves various functions such as transporting hydrophobic ligands across the cellular membrane, regulating immune responses, keeping iron balance, and fostering epithelial cell differentiation. LCN2 plays a crucial role in several physiological processes. LCN2 expression is upregulated in a variety of human diseases and cancers. High levels of LCN2 are specifically linked to breast cancer (BC) cell proliferation, apoptosis, invasion, migration, angiogenesis, immune regulation, chemotherapy resistance, and prognosis. As a result, LCN2 has gained attention as a potential therapeutic target for BC. This article offered an in-depth review of the advancement of LCN2 in the context of BC occurrence and development.
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Neoplasias de la Mama , Humanos , Femenino , Lipocalina 2/metabolismo , Neoplasias de la Mama/metabolismo , Proteínas de Fase Aguda/metabolismo , Lipocalinas/metabolismo , Macrófagos/metabolismoRESUMEN
Background: Accurate assessment of lateral cervical lymph node metastasis (LLNM) involvement is important for treating papillary thyroid carcinoma (PTC). Thyroglobulin is associated with LLNM, but there may be differences in the diagnostic value of serum thyroglobulin (sTg) and fine needle aspiration washout fluid thyroglobulin (FNA-Tg). Herein, we investigated the optimal cutoff value (OCV) of sTg and FNA-Tg and their diagnostic performance. Methods: We enrolled 116 PTC patients who underwent radical resection of thyroid carcinoma with lateral cervical lymph node dissection at the Affiliated Hospital of Zunyi Medical University from June 2018 to July 2022. We used the receiver operating characteristic (ROC) curve analysis to determine the OCV for sTg and FNA-Tg to diagnose LLNM in PTC patients. We also evaluated the performance of FNA-Tg, sTg, fine needle aspiration cytology (FNAC), and their combinations for diagnosis. Pathological results were the gold standard. Results: We performed 125 lymph node dissections, 106 had metastasis, and 19 did not. The OCV for sTg was 17.31 ng/mL [area under the curve (AUC) =0.760, sensitivity =78.30%, specificity =73.68%, and accuracy =77.60%]. Meanwhile, the OCV for FNA-Tg was 4.565 ng/mL (AUC =0.948, sensitivity =89.62%, specificity =100%, and accuracy =91.20%). The combination of FNAC and FNA-Tg presented the greatest diagnostic performance for LLNM detection in PTC patients. Moreover, serum antithyroglobulin antibody (TgAb) was not correlated with sTg or FNA-Tg levels. Conclusions: The cutoff value for the diagnosis of LLNM in PTC are sTg >17.31 ng/mL or FNA-Tg >4.565 ng/mL. The combination method of FNA-Tg and FNAC is the most optimal choice for the diagnosis of LLNM and is highly recommended for further clinical application.
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Plant pathogens are challenged by host-derived iron starvation or excess during infection, but the mechanism of plant pathogens rapidly adapting to the dynamic host iron environments to assimilate iron for invasion and colonization remains largely unexplored. Here, we found that the GATA transcription factor SreC in Curvularia lunata is required for virulence and adaption to the host iron excess environment. SreC directly binds to the ATGWGATAW element in an iron-dependent manner to regulate the switch between different iron assimilation pathways, conferring adaption to host iron environments in different trophic stages of C. lunata. SreC also regulates the transition of trophic stages and developmental processes in C. lunata. SreC-dependent adaption to host iron environments is essential to the infectious growth and survival of C. lunata. We also demonstrate that CgSreA (a SreC orthologue) plays a similar role in Colletotrichum graminicola. We conclude that Sre mediates adaption to the host iron environment during infection, and the function is conserved in hemibiotrophic fungi.
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Curvularia , Proteínas Fúngicas , Hierro , Hierro/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , VirulenciaRESUMEN
Cultivating drought-tolerant tea varieties enhances both yield and quality of tea plants in northern China. However, the mechanisms underlying their drought tolerance remain largely unknown. Here we identified a key regulator called CsREV, which differentially regulates xylem patterns between leaves and stems, thereby conferring drought tolerance in tea plants. When drought occurs, upregulation of CsREV activates the CsVND7a-dependent xylem vessel differentiation. However, when drought persists, the vessel differentiation is hindered as CsVND7a is downregulated by CsTCP4a. This, combined with the CsREV-promoted secondary-cell-wall thickness of xylem vessel, leads to the enhanced curling of leaves, a characteristic closely associated with plant drought tolerance. Notably, this inhibitory effect of CsTCP4a on CsVND7a expression is absent in stems, allowing stem xylem vessels to continuously differentiate. Overall, the CsREV-CsTCP4-CsVND7 module is differentially utilized to shape the xylem patterns in leaves and stems, potentially balancing water transportation and utilization to improve tea plant drought tolerance.
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Sequías , Regulación de la Expresión Génica de las Plantas , Hojas de la Planta , Proteínas de Plantas , Tallos de la Planta , Xilema , Xilema/metabolismo , Hojas de la Planta/metabolismo , Hojas de la Planta/fisiología , Tallos de la Planta/metabolismo , Tallos de la Planta/fisiología , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Camellia sinensis/fisiología , Camellia sinensis/genética , Camellia sinensis/metabolismo , Adaptación FisiológicaRESUMEN
Karrikins and strigolactones govern plant development and environmental responses through closely related signaling pathways. The transcriptional repressor proteins SUPPRESSOR OF MAX2 1 (SMAX1), SMAX1-like2 (SMXL2), and D53-like SMXLs mediate karrikin and strigolactone signaling by directly binding downstream genes or by inhibiting the activities of transcription factors. In this study, we characterized the non-transcriptional regulatory activities of SMXL proteins in Arabidopsis. We discovered that SMAX1 and SMXL2 with mutations in their ethylene-response factor-associated amphiphilic repression (EAR) motif had undetectable or weak transcriptional repression activities but still partially rescued the hypocotyl elongation defects and fully reversed the cotyledon epinasty defects of the smax1 smxl2 mutant. SMAX1 and SMXL2 directly interact with PHYTOCHROME INTERACTION FACTOR 4 (PIF4) and PIF5 to enhance their protein stability by interacting with phytochrome B (phyB) and suppressing the association of phyB with PIF4 and PIF5. The karrikin-responsive genes were then identified by treatment with GR24ent-5DS, a GR24 analog showing karrikin activity. Interestingly, INDOLE-3-ACETIC ACID INDUCIBLE 29 (IAA29) expression was repressed by GR24ent-5DS treatment in a PIF4- and PIF5-dependent and EAR-independent manner, whereas KARRIKIN UPREGULATED F-BOX 1 (KUF1) expression was induced in a PIF4- and PIF5-independent and EAR-dependent manner. Furthermore, the non-transcriptional regulatory activity of SMAX1, which is independent of the EAR motif, had a global effect on gene expression. Taken together, these results indicate that non-transcriptional regulatory activities of SMAX1 and SMXL2 mediate karrikin-regulated seedling response to red light.