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The root endophytic fungus Serendipita indica establishes beneficial symbioses with a broad spectrum of plants and enhances host resilience against biotic and abiotic stresses. However, little is known about the mechanisms underlying S. indica-mediated plant protection. Here, we report S. indica effector (SIE) 141 and its host target CDSP32, a conserved thioredoxin-like protein, and underlying mechanisms for enhancing pathogen resistance and abiotic salt tolerance in Arabidopsis thaliana. SIE141 binding interfered with canonical targeting of CDSP32 to chloroplasts, leading to its re-location into the plant nucleus. This nuclear translocation is essential for both their interaction and resistance function. Furthermore, SIE141 enhanced oxidoreductase activity of CDSP32, leading to CDSP32-mediated monomerization and activation of NON-EXPRESSOR OF PATHOGENESIS-RELATED 1 (NPR1), a key regulator of systemic resistance. Our findings provide functional insights on how S. indica transfers well-known beneficial effects to host plants and indicate CDSP32 as a genetic resource to improve plant resilience to abiotic and biotic stresses.
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Arabidopsis , Estrés Salino , Simbiosis , Arabidopsis/microbiología , Arabidopsis/fisiología , Arabidopsis/genética , Basidiomycota/fisiología , Oxidorreductasas/metabolismo , Oxidorreductasas/genética , Núcleo Celular/metabolismo , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Plastidios/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Enfermedades de las Plantas/microbiologíaRESUMEN
There is an urgent need for novel protection strategies to sustainably secure crop production under changing climates. Studying microbial effectors, defined as microbe-derived proteins that alter signalling inside plant cells, has advanced our understanding of plant immunity and microbial plant colonisation strategies. Our understanding of effectors in the establishment and beneficial outcome of plant symbioses is less well known. Combining functional and comparative interaction assays uncovered specific symbiont effector targets in highly interconnected plant signalling networks and revealed the potential of effectors in beneficially modulating plant traits. The diverse functionality of symbiont effectors differs from the paradigmatic immuno-suppressive function of pathogen effectors. These effectors provide solutions for improving crop resilience against climate stress by their evolution-driven specification in host protein targeting and modulation. Symbiont effectors represent stringent tools not only to identify genetic targets for crop breeding, but to serve as applicable agents in crop management strategies under changing environments.
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Proteínas de Plantas , Resiliencia Psicológica , Proteínas de Plantas/metabolismo , Fitomejoramiento , Plantas/metabolismo , SimbiosisRESUMEN
BACKGROUND: Despite the knowledge that the soil-plant-microbiome nexus is shaped by interactions amongst its members, very little is known about how individual symbioses regulate this shaping. Even less is known about how the agriculturally important symbiosis of nitrogen-fixing rhizobia with legumes is impacted according to soil type, yet this knowledge is crucial if we are to harness or improve it. We asked how the plant, soil and microbiome are modulated by symbiosis between the model legume Medicago truncatula and different strains of Sinorhizobium meliloti or Sinorhizobium medicae whose nitrogen-fixing efficiency varies, in three distinct soil types that differ in nutrient fertility, to examine the role of the soil environment upon the plant-microbe interaction during nodulation. RESULTS: The outcome of symbiosis results in installment of a potentially beneficial microbiome that leads to increased nutrient uptake that is not simply proportional to soil nutrient abundance. A number of soil edaphic factors including Zn and Mo, and not just the classical N/P/K nutrients, group with microbial community changes, and alterations in the microbiome can be seen across different soil fertility types. Root endosphere emerged as the plant microhabitat more affected by this rhizobial efficiency-driven community reshaping, manifested by the accumulation of members of the phylum Actinobacteria. The plant in turn plays an active role in regulating its root community, including sanctioning low nitrogen efficiency rhizobial strains, leading to nodule senescence in particular plant-soil-rhizobia strain combinations. CONCLUSIONS: The microbiome-soil-rhizobial dynamic strongly influences plant nutrient uptake and growth, with the endosphere and rhizosphere shaped differentially according to plant-rhizobial interactions with strains that vary in nitrogen-fixing efficiency levels. These results open up the possibility to select inoculation partners best suited for plant, soil type and microbial community. Video Abstract.
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Medicago truncatula , Rhizobium , Sinorhizobium meliloti , Fijación del Nitrógeno/fisiología , Medicago truncatula/microbiología , Sinorhizobium meliloti/fisiología , Simbiosis/fisiologíaRESUMEN
Plants have benefited from interactions with symbionts for coping with challenging environments since the colonisation of land. The mechanisms of symbiont-mediated beneficial effects and similarities and differences to pathogen strategies are mostly unknown. Here, we use 106 (effector-) proteins, secreted by the symbiont Serendipita indica (Si) to modulate host physiology, to map interactions with Arabidopsis thaliana host proteins. Using integrative network analysis, we show significant convergence on target-proteins shared with pathogens and exclusive targeting of Arabidopsis proteins in the phytohormone signalling network. Functional in planta screening and phenotyping of Si effectors and interacting proteins reveals previously unknown hormone functions of Arabidopsis proteins and direct beneficial activities mediated by effectors in Arabidopsis. Thus, symbionts and pathogens target a shared molecular microbe-host interface. At the same time Si effectors specifically target the plant hormone network and constitute a powerful resource for elucidating the signalling network function and boosting plant productivity.
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Proteínas de Arabidopsis , Arabidopsis , Reguladores del Crecimiento de las Plantas , Transducción de Señal , Proteínas de Arabidopsis/genética , HormonasRESUMEN
Matteson homologations of chiral boronic esters with the aid of unsaturated nucleophiles are powerful for gaining access to a range of different O-heterocycles via subsequent ring-closing metatheses. Using this protocol, six- to eight-membered rings become available and almost any position of the ring can be substituted and/or functionalized.
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Background: Successful fixation of the greater trochanter (GT) in total hip arthroplasty (THA) is a challenging task. A wide range of clinical results are reported in the literature despite advancements in fixation technology. Previous studies may have lacked adequate sample sizes to detect differences. This study evaluates nonunion and reoperation rates and determines factors influencing successful fixation of the GT using current-generation cable plate devices. Methods: This retrospective cohort study included 76 patients who underwent surgery requiring fixation of their GT and had at least 1-year radiographic follow-up. Indications for a surgery were periprosthetic fracture (n = 25), revision THA requiring an extended trochanteric osteotomy (n = 30), GT fracture (n = 3), GT fracture nonunion (n = 9), and complex primary THA (n = 3). Primary outcomes were radiographic union and reoperation. Secondary objectives were patient and plate factors influencing radiographic union. Results: At a mean radiographic follow-up of 2.5 years, the union rate was 76.3% with a nonunion rate of 23.7%. Twenty-eight patients underwent plate removal, reasons for removal were pain (n = 21), nonunion (n = 5), and hardware failure (n = 2). Seven patients had cable-induced bone loss. Anatomic positioning of the plate (P = .03) and number of cables used (P = .03) were associated with radiographic union. Nonunion was associated with a higher incidence (+30%) of hardware failure due to broken cable(s) (P = .005). Conclusions: Greater trochanteric nonunion remains a problem in THA. Successful fixation using current-generation cable plate devices may be influenced by plate positioning and number of cables used. Plate removal may be required for pain or cable-induced bone loss.
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Prenatal inflammatory insults accompany prematurity and provoke diffuse white matter injury (DWMI), which is associated with increased risk of neurodevelopmental pathologies, including autism spectrum disorders. DWMI results from maturation arrest of oligodendrocyte precursor cells (OPCs), a process that is poorly understood. Here, by using a validated mouse model of OPC maturation blockade, we provide the genome-wide ID card of the effects of neuroinflammation on OPCs that reveals the architecture of global cell fate issues underlining their maturation blockade. First, we find that, in OPCs, neuroinflammation takes advantage of a primed epigenomic landscape and induces abnormal overexpression of genes of the immune/inflammatory pathways: these genes strikingly exhibit accessible chromatin conformation in uninflamed OPCs, which correlates with their developmental, stage-dependent expression, along their normal maturation trajectory, as well as their abnormal upregulation upon neuroinflammation. Consistently, we observe the positioning on DNA of key transcription factors of the immune/inflammatory pathways (IRFs, NFkB), in both unstressed and inflamed OPCs. Second, we show that, in addition to the general perturbation of the myelination program, neuroinflammation counteracts the physiological downregulation of the cell cycle pathway in maturing OPCs. Neuroinflammation therefore perturbs cell identity in maturing OPCs, in a global manner. Moreover, based on our unraveling of the activity of genes of the immune/inflammatory pathways in prenatal uninflamed OPCs, the mere suppression of these proinflammatory mediators, as currently proposed in the field, may not be considered as a valid neurotherapeutic strategy.
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Oligodendroglía , Sustancia Blanca , Ratones , Animales , Embarazo , Femenino , Oligodendroglía/metabolismo , Ratones Transgénicos , Sustancia Blanca/patología , Epigenómica , Ratones Endogámicos C57BL , Enfermedades Neuroinflamatorias , Diferenciación Celular , Ciclo Celular/genética , Epigénesis GenéticaRESUMEN
Roots are a highly organised plant tissue consisting of different cell types with distinct developmental functions defined by cell identity networks. Roots are the target of some of the most devastating diseases and possess a highly effective immune system. The recognition of microbe- or plant-derived molecules released in response to microbial attack is highly important in the activation of complex immunity gene networks. Development and immunity are intertwined, and immunity activation can result in growth inhibition. In turn, by connecting immunity and cell identity regulators, cell types are able to launch a cell type-specific immunity based on the developmental function of each cell type. By this strategy, fundamental developmental processes of each cell type contribute their most basic functions to drive cost-effective but highly diverse and, thus, efficient immune responses. This review highlights the interdependence of root development and immunity and how the developmental age of root cells contributes to positive and negative outcomes of development-immunity cross-talk.
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In more than 30 years of aptamer research, it has become widely accepted that aptamers are fascinating binding molecules for a vast variety of applications. However, the majority of targets have been proteins, although special variants of the so-called SELEX process for the molecular evolution of specific aptamers have also been developed, allowing for the targeting of small molecules as well as larger structures such as cells and even cellular networks of human (tumor) tissues. Although the provocative thesis is widely accepted in the field, that is, in principle, any level of complexity for SELEX targets is possible, the number of studies on whole organs or at least parts of them is limited. To pioneer this thesis, and based on our FluCell-SELEX process, here, we have developed polyclonal aptamer libraries against apices and the elongation/differentiation zones of plant roots as examples of organs. We show that dedicated libraries can specifically label the respective parts of the root, allowing us to distinguish them in fluorescence microscopy. We consider this achievement to be an initial but important evidence for the robustness of this SELEX variant. These libraries may be valuable tools for plant research and a promising starting point for the isolation of more specific individual aptamers directed against root-specific epitopes.
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Aptámeros de Nucleótidos , Arabidopsis , Humanos , Aptámeros de Nucleótidos/química , Arabidopsis/genética , Arabidopsis/metabolismo , Epítopos , Técnica SELEX de Producción de Aptámeros , Raíces de Plantas/metabolismoRESUMEN
Mitochondrial function depends on the RNA processing of mitochondrial gene transcripts by nucleus-encoded proteins. This posttranscriptional processing involves the large group of nuclear-encoded pentatricopeptide repeat (PPR) proteins. Mitochondrial processes represent a crucial part in animal immunity, but whether mitochondria play similar roles in plants remains unclear. Here, we report the identification of RESISTANCE TO PHYTOPHTHORA PARASITICA 7 (AtRTP7), a P-type PPR protein, in Arabidopsis thaliana and its conserved function in immunity to diverse pathogens across distantly related plant species. RTP7 affects the levels of mitochondrial reactive oxygen species (mROS) by participating in RNA splicing of nad7, which encodes a critical subunit of the mitochondrial respiratory chain Complex I, the largest of the four major components of the mitochondrial oxidative phosphorylation system. The enhanced resistance of rtp7 plants to Phytophthora parasitica is dependent on an elevated mROS burst, but might be independent from the ROS burst associated with plasma membrane-localized NADPH oxidases. Our study reveals the immune function of RTP7 and the defective processing of Complex I subunits in rtp7 plants resulted in enhanced resistance to both biotrophic and necrotrophic pathogens without affecting overall plant development.
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Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Complejo I de Transporte de Electrón/genética , Complejo I de Transporte de Electrón/metabolismo , Regulación de la Expresión Génica de las Plantas/genética , Mitocondrias/genética , Mitocondrias/metabolismo , Proteínas Mitocondriales/genética , Proteínas Mitocondriales/metabolismo , Inmunidad de la Planta/genética , Procesamiento Postranscripcional del ARN , Empalme del ARN , ARN Mitocondrial/metabolismo , Estallido RespiratorioRESUMEN
Here, we report an improved and complete genome sequence of Sinorhizobium (Ensifer) meliloti strain WSM1022, a microsymbiont of Medicago species, revealing its tripartite structure. This improved genome sequence was generated combining Illumina and Oxford nanopore sequencing technologies to better understand the symbiotic properties of the bacterium. The 6.75 Mb WSM1022 genome consists of three scaffolds, corresponding to a chromosome (3.70 Mb) and the pSymA (1.38 Mb) and pSymB (1.66 Mb) megaplasmids. The assembly has an average GC content of 62.2% and a mean coverage of 77X. Genome annotation of WSM1022 predicted 6058 protein coding sequences (CDSs), 202 pseudogenes, 9 rRNAs (3 each of 5S, 16S, and 23S), 55 tRNAs, and 4 ncRNAs. We compared the genome of WSM1022 to two other rhizobial strains, closely related Sinorhizobium (Ensifer) meliloti Sm1021 and Sinorhizobium (Ensifer) medicae WSM419. Both WSM1022 and WSM419 species are high-efficiency rhizobial strains when in symbiosis with Medicago truncatula, whereas Sm1021 is ineffective. Our findings report significant genomic differences across the three strains with some similarities between the meliloti strains and some others between the high efficiency strains WSM1022 and WSM419. The addition of this high-quality rhizobial genome sequence in conjunction with comparative analyses will help to unravel the features that make a rhizobial symbiont highly efficient for nitrogen fixation.
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Background and Objectives: Producing consistent measures of femoral version amongst observers are necessary to allow for an assessment of version for possible corrective procedures. The purpose of this study was to compare two computed tomography (CT)-based techniques for the reliability of measuring femoral version amongst observers. Materials and Methods: Review was performed for 15 patients post-femoral nailing for comminuted (Winquist III and IV) femoral shaft fractures where CT scanograms were obtained. Two CT-based techniques were utilized to measure femoral version by five observers. Results: The mean femoral version, when utilizing a proximal line drawn down the center of the femoral head-neck through CT, was 9.50 ± 4.82°, while the method utilizing the head and shaft at lesser trochanter centers produced a mean version of 18.73 ± 2.69°. A significant difference was noted between these two (p ≤ 0.001). The method of measuring in the center of the femoral head and neck produced an intraclass correlation coefficient (ICC) of 0.960 with a 95% confidence interval lower bound of 0.909 and upper bound of 0.982. For the method assessing version via the center of the head and shaft at the lesser trochanter region, the ICC was 0.993 with a 95% confidence interval lower bound of 0.987 and an upper bound of 0.996. Conclusions: The method of measuring version proximally through a CT image of the femoral head-neck versus overlaying the femoral head with the femoral shaft at the most prominent aspect of the lesser trochanter produces differing version measurements by roughly 10° while yielding an almost perfect interobserver reliability in the new technique. Both techniques result in significantly high interobserver reliability.
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Cuello Femoral , Fémur , Fémur/diagnóstico por imagen , Fémur/cirugía , Cuello Femoral/diagnóstico por imagen , Humanos , Reproducibilidad de los Resultados , Estudios Retrospectivos , Tomografía Computarizada por Rayos XRESUMEN
The Mediator complex controls transcription of most eukaryotic genes with individual subunits required for the control of particular gene regulons in response to various perturbations. In this study, we reveal the roles of the plant Mediator subunits MED16, MED14, and MED2 in regulating transcription in response to the phytohormone abscisic acid (ABA) and we determine which cis elements are under their control. Using synthetic promoter reporters we established an effective system for testing relationships between subunits and specific cis-acting motifs in protoplasts. Our results demonstrate that MED16, MED14, and MED2 are required for the full transcriptional activation by ABA of promoters containing both the ABRE (ABA-responsive element) and DRE (drought-responsive element). Using synthetic promoter motif concatamers, we showed that ABA-responsive activation of the ABRE but not the DRE motif was dependent on these three Mediator subunits. Furthermore, the three subunits were required for the control of water loss from leaves but played no role in ABA-dependent growth inhibition, highlighting specificity in their functions. Our results identify new roles for three Mediator subunits, provide a direct demonstration of their function and highlight that our experimental approach can be utilized to identify the function of subunits of plant transcriptional regulators.
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The advent of single-cell sequencing started a new era of transcriptomic and genomic research, advancing our knowledge of the cellular heterogeneity and dynamics. Cell type annotation is a crucial step in analyzing single-cell RNA sequencing data, yet manual annotation is time-consuming and partially subjective. As an alternative, tools have been developed for automatic cell type identification. Different strategies have emerged to ultimately associate gene expression profiles of single cells with a cell type either by using curated marker gene databases, correlating reference expression data, or transferring labels by supervised classification. In this review, we present an overview of the available tools and the underlying approaches to perform automated cell type annotations on scRNA-seq data.
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OBJECTIVE: To assess the effect of a routine medication review service in German community pharmacies (ATHINA) on drug-related problems (DRPs) and patient-related outcomes. MATERIALS AND METHODS: From 2015 to 2017, ATHINA patients were invited by their pharmacists to participate in a prospective, observational trial, meaning that they needed to attend to a follow-up visit (T2) 3 - 6 months after the routine ATHINA baseline (T0) and concluding visit (T1) to assess implementation rates of the pharmacists' interventions. Moreover, they were asked to fill in 2 surveys on drug treatment-related quality of life and satisfaction with the amount of information received about medicines at T0, T1, and T2. RESULTS: Of 132 recruited patients, 115 completed T2. At T0, pharmacists documented a DRP or information need for 114 of 115 patients. About half of these issues were resolved leading to 43/115 patients without any DRP or information need at T1 and 50/115 patients without any DRP or information need at T2 (i.e., absolute reduction by 42.6%, p < 0.001). Also, the number of patients who felt that their daily life was not impaired at all or only very slightly by their drug treatment increased from 54.7% (58/106) at T0 to 67.6% (73/108, p = 0.011) at T2. While the overall satisfaction score with the amount of information on medicines increased from 10.2 ± 5.5 at T0 over 14.6 ± 3.8 (T1) to 15.4 ± 3.1 (T2, p < 0.001), this increase did not correlate with reduced information needs. CONCLUSION: The results suggest that the intervention improves medication- and patient-related outcomes. However, causal relationships are still questionable.
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Servicios Comunitarios de Farmacia , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Farmacias , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/prevención & control , Alemania , Humanos , Farmacéuticos , Estudios Prospectivos , Calidad de VidaRESUMEN
The interaction of plants with complex microbial communities is the result of co-evolution over millions of years and contributed to plant transition and adaptation to land. The ability of plants to be an essential part of complex and highly dynamic ecosystems is dependent on their interaction with diverse microbial communities. Plant microbiota can support, and even enable, the diverse functions of plants and are crucial in sustaining plant fitness under often rapidly changing environments. The composition and diversity of microbiota differs between plant and soil compartments. It indicates that microbial communities in these compartments are not static but are adjusted by the environment as well as inter-microbial and plant-microbe communication. Hormones take a crucial role in contributing to the assembly of plant microbiomes, and plants and microbes often employ the same hormones with completely different intentions. Here, the function of hormones as go-betweens between plants and microbes to influence the shape of plant microbial communities is discussed. The versatility of plant and microbe-derived hormones essentially contributes to the creation of habitats that are the origin of diversity and, thus, multifunctionality of plants, their microbiota and ultimately ecosystems.
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Microbiota , Reguladores del Crecimiento de las Plantas/fisiología , Plantas/microbiología , Ácido Abscísico/metabolismo , Ciclopentanos/metabolismo , Etilenos/metabolismo , Ácidos Indolacéticos/metabolismo , Microbiota/fisiología , Oxilipinas/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo , Raíces de Plantas/microbiología , Raíces de Plantas/fisiología , Rizosfera , Ácido Salicílico/metabolismo , Transducción de SeñalRESUMEN
Immune cell function is influenced by metabolic conditions. Low-glucose, high-lactate environments, such as the placenta, gastrointestinal tract, and the tumor microenvironment, are immunosuppressive, especially for glycolysis-dependent effector T cells. We report that nicotinamide adenine dinucleotide (NAD+), which is reduced to NADH by lactate dehydrogenase in lactate-rich conditions, is a key point of metabolic control in T cells. Reduced NADH is not available for NAD+-dependent enzymatic reactions involving glyceraldehyde 3-phosphate dehydrogenase (GAPDH) and 3-phosphoglycerate dehydrogenase (PGDH). We show that increased lactate leads to a block at GAPDH and PGDH, leading to the depletion of post-GAPDH glycolytic intermediates, as well as the 3-phosphoglycerate derivative serine that is known to be important for T cell proliferation. Supplementing serine rescues the ability of T cells to proliferate in the presence of lactate-induced reductive stress. Directly targeting the redox state may be a useful approach for developing novel immunotherapies in cancer and therapeutic immunosuppression.
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Ácido Láctico/metabolismo , NAD/metabolismo , Proliferación Celular , Humanos , Oxidación-ReducciónRESUMEN
While root diseases are among the most devastating stresses in global crop production, our understanding of root immunity is still limited relative to our knowledge of immune responses in leaves. Considering that root performance is based on the concerted functions of its different cell types, we undertook a cell type-specific transcriptome analysis to identify gene networks activated in epidermis, cortex, and pericycle cells of Arabidopsis (Arabidopsis thaliana) roots challenged with two immunity elicitors, the bacterial flagellin-derived flg22 and the endogenous Pep1 peptide. Our analyses revealed distinct immunity gene networks in each cell type. To further substantiate our understanding of regulatory patterns underlying these cell type-specific immunity networks, we developed a tool to analyze paired transcription factor binding motifs in the promoters of cell type-specific genes. Our study points toward a connection between cell identity and cell type-specific immunity networks that might guide cell types in launching immune response according to the functional capabilities of each cell type.