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1.
BMC Plant Biol ; 24(1): 685, 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39026182

RESUMEN

BACKGROUND: Developing novel germplasm by using wheat wild related species is an effective way to rebuild the wheat resource bank. The Psathyrostachys huashanica Keng (P. huashanica, 2n = 2x = 14, NsNs) is regarded as a superior species to improve wheat breeding because of its multi-resistance, early maturation and numerous tiller traits. Introducing genetic components of P. huashanica into the common wheat background is the most important step in achieving the effective use. Therefore, the cytogenetic characterization and influence of the introgressed P. huashanica large segment chromosomes in the wheat background is necessary to be explored. RESULTS: In this study, we characterized a novel derived line, named D88-2a, a progeny of the former characterized wheat-P. huashanica partial amphiploid line H8911 (2n = 7x = 49, AABBDDNs). Cytological identification showed that the chromosomal composition of D88-2a was 2n = 44 = 22II, indicating the addition of exogenous chromosomes. Genomic in situ hybridization demonstrated that the supernumerary chromosomes were a pair of homologues from the P. huashanica and could be stably inherited in the common wheat background. Molecular markers and 15 K SNP array indicated that the additional chromosomes were derived from the sixth homoeologous group (i.e., 6Ns) of P. huashanica. Based on the distribution of the heterozygous single-nucleotide polymorphism sites and fluorescence in situ hybridization karyotype of each chromosome, this pair of additional chromosomes was confirmed as P. huashanica 6Ns large segment chromosomes, which contained the entire short arm and the proximal centromere portion of the long arm. In terms of the agronomic traits, the addition line D88-2a exhibited enhanced stripe rust resistance, improved spike characteristics and increased protein content than its wheat parent line 7182. CONCLUSIONS: The new wheat germplasm D88-2a is a novel cytogenetically stable wheat-P. huashanica 6Ns large segment addition line, and the introgressed large segment alien chromosome has positive impact on plant spikelet number and stripe rust resistance. Thus, this germplasm can be used for genetic improvement of cultivated wheat and the study of functional alien chromosome segment.


Asunto(s)
Cromosomas de las Plantas , Resistencia a la Enfermedad , Enfermedades de las Plantas , Triticum , Triticum/genética , Triticum/microbiología , Triticum/crecimiento & desarrollo , Cromosomas de las Plantas/genética , Resistencia a la Enfermedad/genética , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/genética , Fitomejoramiento , Poaceae/genética , Poaceae/microbiología , Poaceae/crecimiento & desarrollo , Basidiomycota/fisiología
2.
Mol Ther ; 32(6): 1687-1700, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38582966

RESUMEN

Deep-learning-based methods for protein structure prediction have achieved unprecedented accuracy, yet their utility in the engineering of protein-based binders remains constrained due to a gap between the ability to predict the structures of candidate proteins and the ability toprioritize proteins by their potential to bind to a target. To bridge this gap, we introduce Automated Pairwise Peptide-Receptor Analysis for Screening Engineered proteins (APPRAISE), a method for predicting the target-binding propensity of engineered proteins. After generating structural models of engineered proteins competing for binding to a target using an established structure prediction tool such as AlphaFold-Multimer or ESMFold, APPRAISE performs a rapid (under 1 CPU second per model) scoring analysis that takes into account biophysical and geometrical constraints. As proof-of-concept cases, we demonstrate that APPRAISE can accurately classify receptor-dependent vs. receptor-independent adeno-associated viral vectors and diverse classes of engineered proteins such as miniproteins targeting the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike, nanobodies targeting a G-protein-coupled receptor, and peptides that specifically bind to transferrin receptor or programmed death-ligand 1 (PD-L1). APPRAISE is accessible through a web-based notebook interface using Google Colaboratory (https://tiny.cc/APPRAISE). With its accuracy, interpretability, and generalizability, APPRAISE promises to expand the utility of protein structure prediction and accelerate protein engineering for biomedical applications.


Asunto(s)
Unión Proteica , Ingeniería de Proteínas , SARS-CoV-2 , Ingeniería de Proteínas/métodos , Humanos , SARS-CoV-2/metabolismo , SARS-CoV-2/genética , Modelos Moleculares , Glicoproteína de la Espiga del Coronavirus/metabolismo , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/química , Conformación Proteica , Anticuerpos de Dominio Único/química , Anticuerpos de Dominio Único/genética , Anticuerpos de Dominio Único/metabolismo , Aprendizaje Profundo , COVID-19/virología , Antígeno B7-H1/metabolismo , Antígeno B7-H1/genética , Antígeno B7-H1/química , Dependovirus/genética , Vectores Genéticos/química , Vectores Genéticos/genética , Vectores Genéticos/metabolismo
3.
AMB Express ; 14(1): 39, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38647736

RESUMEN

Interactions between microorganisms and plants can stimulate plant growth and promote nitrogen cycling. Nitrogen fertilizers are routinely used in agriculture to improve crop growth and yield; however, poor use efficiency impairs the optimal utilization of such fertilizers. Differences in the microbial diversity and plant growth of rice soil under different nitrogen application conditions and the expression of nitrogen-use efficiency-related genes have not been previously investigated. Therefore, this study investigates how nitrogen application and nitrogen-use efficiency-related gene NRT1.1B expression affect the soil microbial diversity and growth indices of two rice varieties, Huaidao 5 and Xinhuai 5. In total, 103,463 and 98,427 operational taxonomic units were detected in the soils of the Huaidao 5 and Xinhuai 5 rice varieties, respectively. The Shannon and Simpson indices initially increased and then decreased, whereas the Chao and abundance-based coverage estimator indices decreased after the application of nitrogen fertilizer. Nitrogen fertilization also reduced soil bacterial diversity and richness, as indicated by the reduced abundances of Azotobacter recorded in the soils of both rice varieties. Nitrogen application initially increased and then decreased the grain number per panicle, yield per plant, root, stem, and leaf nitrogen, total nitrogen content, glutamine synthetase, nitrate reductase, urease, and root activities of both varieties. Plant height showed positive linear trends in response to nitrogen application, whereas thousand-grain weights showed a negative trend. Our findings may be used to optimize nitrogen fertilizer use for rice cultivation and develop crop-variety-specific strategies for nitrogen fertilizer application.

4.
Artículo en Inglés | MEDLINE | ID: mdl-38687668

RESUMEN

Lifelong deep reinforcement learning (DRL) approaches are commonly employed to adapt continuously to new tasks without forgetting previously acquired knowledge. While current lifelong DRL methods have shown promising advancements in retaining acquired knowledge, they suffer from significant adaptation efforts (i.e., longer training duration) and suboptimal policy when transferring to a new task that significantly deviates from previously learned tasks, a phenomenon known as the few-shot generalization challenge. In this work, we propose a generic approach that equips existing lifelong DRL methods with the capability of few-shot generalization. First, we employ selective experience reuse by leveraging the experience of encountered states, improving adaptation training for new tasks. Then, a relaxed softmax function is applied to the target Q values to improve the accuracy of evaluated Q values, leading to more optimal policies. Finally, we measure and reduce the discrepancy in data distribution between the policy and off-policy samples, resulting in improved adaptation efficiency. Extensive experiments have been conducted on three typical benchmarks to compare our approach with six representative lifelong DRL methods and two state-of-the-art (SOTA) few-shot DRL methods regarding their training speed, episode return, and average return of all episodes. Experimental results substantiate that our method improves the return of six lifelong DRL methods by at least 25%.

6.
Phytopathology ; 114(2): 454-463, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38394356

RESUMEN

Wheat sheath blight caused by the necrotic fungal pathogen Rhizoctonia cerealis is responsible for severe damage to bread wheat. Reactive oxygen species (ROS) are vital for stress resistance by plants and their homeostasis plays an important role in wheat resistance to sheath blight. Valine-glutamine (VQ) proteins play important roles in plant growth and development, and responses to biotic and abiotic stresses. However, the functional mechanism mediated by wheat VQ protein in response to sheath blight via ROS homeostasis regulation is unclear. In this study, we identified TaVQ22 protein containing the VQ motif and clarified the functional mechanisms involved in the defense of wheat against R. cerealis. TaVQ22 silencing reduced the accumulation of ROS and enhanced the resistance of wheat to R. cerealis. In addition, we showed that TaVQ22 regulated ROS generation by interacting with the WRKY transcription factor TaWRKY19-2B, thereby indicating that TaVQ22 and TaWRKY19-2B formed complexes in the plant cell nucleus. Yeast two-hybrid analysis showed that the VQ motif in TaVQ22 is crucial for the interaction, where it inhibits the transcriptional activation function of TaWRKY19-2B. In summary, TaVQ22 interacts with TaWRKY19-2B to regulate ROS homeostasis and negatively regulate the defense response to R. cerealis infection. This study provides novel insights into the mechanism that allows VQ protein to mediate the immune response in plants.


Asunto(s)
Enfermedades de las Plantas , Triticum , Triticum/genética , Especies Reactivas de Oxígeno , Homeostasis , Desarrollo de la Planta , Saccharomyces cerevisiae
7.
Environ Sci Pollut Res Int ; 31(8): 11898-11911, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38225492

RESUMEN

Rice is the main food crops with the higher capacity for cadmium (Cd) uptake, necessitating the urgent need for remediation measures to address Cd in paddy soil. Reasonable agronomic methods are convenient and favorable for fixing the issue. In this study, a pot experiment was employed to evaluate the effects of two foliar (NaH2PO4, SDP; KH2PO4, PDP) and two solid phosphate fertilizers (double-superphosphate, DSP; calcium-magnesium phosphate, CMP) on uptake and remobilization of Cd in rice plants under the low-P and rich-Cd soil. The results revealed that these four phosphorus fertilizer significantly down-regulated the relative expression of OsNRAMP5 involved in Cd absorption, while up-regulated OsPCS1 expression and increased distribution of Cd into the cell wall in roots. Furthermore, phosphorus fertilizer resulted in a significant decrease in the relative expression of OsLCT1 in stems and OsLCD in leaves, decreased the transfer factor of Cd from shoots to grains, and ulterior reduced the Cd accumulation in three protein components of globulin, albumin, and glutelin, making the average Cd concentration of brown rice decreased by 82.96%. These results comprehensively indicate that in situations with similar soil backgrounds, the recommended application of solid CMP and foliar PDP can alleviate the toxicity of Cd by reducing its absorption and remobilization.


Asunto(s)
Oryza , Contaminantes del Suelo , Suelo , Fósforo/metabolismo , Cadmio/análisis , Fertilizantes/análisis , Oryza/metabolismo , Contaminantes del Suelo/análisis
8.
Plant Physiol Biochem ; 207: 108323, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38183904

RESUMEN

Wheat sharp eyespot is a soil-borne disease caused by Rhizoctonia cerealis, which occurs in many countries worldwide and significantly reduces the yield. Thaumatin-like protein (TLP), also known as PR5, is a member of the pathogen response protein family and plays an essential role in plant resistance to pathogen infection. In this study, 131 TaTLP genes were identified from the wheat genome, of which 38 TaTLPs were newly discovered. The TaTLP gene family contains many tandem duplications and fragment duplications, which is a major pathway for gene amplification. Besides, we also analyzed the physicochemical properties, gene structure and promoter cis-acting regulatory elements of all the TaTLP genes. In addition, the expression patterns of nine TaTLPs in response to R. cerealis were analyzed by RT-qPCR. Six TaTLP proteins expressed in vitro had no significant inhibitory effect on R. cerealis, suggesting that these TaTLP proteins may function in other ways. Finally, we performed gene silencing of TaTLP44 in wheat, which increased the expression of some defense-associated genes and improved resistance to R. cerealis. In summary, we systematically analyzed TaTLP family members and demonstrated that TaTLP44 negatively regulates the resistance to R. cerealis by controlling expression of defense-associated genes. These results provide new insights into the functional mechanism of TaTLP proteins.


Asunto(s)
Basidiomycota , Triticum , Triticum/genética , Triticum/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Enfermedades de las Plantas/genética
9.
Plant Physiol Biochem ; 207: 108351, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38217926

RESUMEN

The reduction of cadmium (Cd) accumulation in rice grains through biofortification of essential nutrients like zinc (Zn) and silicon (Si) is an area of study that has gained significant attention. However, there is limited understanding of the mechanism of Zn/Si interaction on Cd accumulation and remobilization in rice plants. This work used a pot experiment to examine the effects of Zn and Si applied singly or in combination on the physiological metabolism of Cd in different rice organs under Cd stress. The results revealed that: Zn/Si application led to a significant decrease in root Cd concentration and reduce the value of Tf Soil-Root in filling stage. The content of phytochelatin (PCs, particularly PC2) and glutathione (GSH) in roots, top and basal nodes were increased with Zn/Si treatment application. Furthermore, Zn/Si treatment promoted the distribution of Cd in cell wall during Cd stress. These findings suggest that Zn/Si application facilitates the compartmentalization of Cd within subcellular structures and enhances PCs production in vegetative organs, thereby reducing Cd remobilization. Zn/Si treatment upregulated the metabolism of amino acid components involved in osmotic regulation, secondary metabolite synthesis, and plant chelating peptide synthesis in vegetative organs. Additionally, it significantly decreased the accumulation of Cd in globulin, albumin, and glutelin, resulting in an average reduction of 50.87% in Cd concentration in milled rice. These results indicate that Zn/Si nutrition plays a crucial role in mitigating heavy metal stress and improving the nutritional quality of rice by regulating protein composition and coordinating amino acid metabolism balance.


Asunto(s)
Metales Pesados , Oryza , Contaminantes del Suelo , Cadmio/metabolismo , Zinc/metabolismo , Silicio/farmacología , Silicio/metabolismo , Metales Pesados/metabolismo , Glutatión/metabolismo , Oryza/metabolismo , Aminoácidos/metabolismo , Contaminantes del Suelo/metabolismo , Suelo
10.
BMC Infect Dis ; 23(1): 844, 2023 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-38036977

RESUMEN

OBJECTIVE: To evaluate the association between traditional laboratory findings and death, and to find risk factors for death in infants with early onset sepsis (EOS). STUDY DESIGN: This was a single-center, case-control, retrospective trial conducted between January 2020 and August 2021. Infants with EOS were enrolled and divided into two groups based on outcome before hospital discharge: non-survivors (Mortality group) and survivors (Survival group). RESULTS: Out of 556 eligible neonates, there were 38 (6.8%) deaths. After univariate analysis and ROC curve analysis, there were a total of 12 values with significant differences (p < 0.05) between two groups, which included birth weight (BW), weight on admission, gestational age, age on admission, mode of delivery, septic shock, heart failure, respiratory failure, pulmonary hypertension, hypothermia, serum lactic acid, and aspartate aminotransferase (AST). Moreover, after multivariate analysis performed for those 12 values, the binary logistic regression analysis showed that taking death as a reference, the BW (OR = 1.00, 95% CI[1.001, 1.002], p < 0.001), PPHN (OR = 2.60, 95% CI[1.04, 6.52], p > 0.001), septic shock (OR = 6.15, 95% CI [2.52, 15.00], p < 0.001), heart failure (OR = 6.22, 95% CI[0.90, 43.05], p > 0.001), serum lactic acid (OR = 0.82, 95%CI[0.75, 0.90], p < 0.001), and AST (OR = 1.00, 95% CI[0.99, 1.00], p > 0.001) could be regarded as risk factors for death with 94.0% correct predictions. CONCLUSIONS: The factors affecting the prognosis of EOS in neonates were BW, PPHN, septic shock, heart failure, serum lactic acid, and AST. Timely correction of these modifiable risk factors for death may decrease the mortality of EOS in neonates.


Asunto(s)
Insuficiencia Cardíaca , Sepsis , Choque Séptico , Recién Nacido , Lactante , Humanos , Estudios Retrospectivos , Factores de Riesgo , Peso al Nacer , Pronóstico , Ácido Láctico
11.
Curr Res Neurobiol ; 4: 100086, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37397806

RESUMEN

Modern neuroscience approaches including optogenetics, calcium imaging, and other genetic manipulations have facilitated our ability to dissect specific circuits in rodent models to study their role in neurological disease. These approaches regularly use viral vectors to deliver genetic cargo (e.g., opsins) to specific tissues and genetically-engineered rodents to achieve cell-type specificity. However, the translatability of these rodent models, cross-species validation of identified targets, and translational efficacy of potential therapeutics in larger animal models like nonhuman primates remains difficult due to the lack of efficient primate viral vectors. A refined understanding of the nonhuman primate nervous system promises to deliver insights that can guide the development of treatments for neurological and neurodegenerative diseases. Here, we outline recent advances in the development of adeno-associated viral vectors for optimized use in nonhuman primates. These tools promise to help open new avenues for study in translational neuroscience and further our understanding of the primate brain.

12.
Nat Nanotechnol ; 18(10): 1241-1251, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37430038

RESUMEN

Crossing the blood-brain barrier in primates is a major obstacle for gene delivery to the brain. Adeno-associated viruses (AAVs) promise robust, non-invasive gene delivery from the bloodstream to the brain. However, unlike in rodents, few neurotropic AAVs efficiently cross the blood-brain barrier in non-human primates. Here we report on AAV.CAP-Mac, an engineered variant identified by screening in adult marmosets and newborn macaques, which has improved delivery efficiency in the brains of multiple non-human primate species: marmoset, rhesus macaque and green monkey. CAP-Mac is neuron biased in infant Old World primates, exhibits broad tropism in adult rhesus macaques and is vasculature biased in adult marmosets. We demonstrate applications of a single, intravenous dose of CAP-Mac to deliver functional GCaMP for ex vivo calcium imaging across multiple brain areas, or a cocktail of fluorescent reporters for Brainbow-like labelling throughout the macaque brain, circumventing the need for germline manipulations in Old World primates. As such, CAP-Mac is shown to have potential for non-invasive systemic gene transfer in the brains of non-human primates.


Asunto(s)
Encéfalo , Callithrix , Humanos , Animales , Recién Nacido , Chlorocebus aethiops , Macaca mulatta/genética , Callithrix/genética , Encéfalo/fisiología , Técnicas de Transferencia de Gen , Neuronas , Vectores Genéticos/genética
13.
Food Chem ; 425: 136537, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37290239

RESUMEN

Psathrostachys huashanica (P. huashanica), a wild relative of common wheat, is widely used in wheat variety improvement because of its many beneficial properties. In this study, we carried out preliminary analysis on the grain and flour quality of wheat-P. huashanica addition line 7182-6Ns and its wheat parents 7182, and found that 7182-6Ns had a higher protein content and great dough rheological characteristics and investigated the reasons for the changes. The results indicated that 7182-6Ns contained exogenous gliadin, which changed the gliadin composition and increased the ratio of gliadin in total gluten proteins, rebuilt gluten microstructure and thus optimized dough extensibility. As the addition of 7182-6Ns gliadin gradually increased to wheat flour, the diameter, crispness and spread rate of biscuit increased, the thickness and hardness decreased, and the colour improved. The current research provides a basis for understanding the introduction of exogenic gliadin to improve biscuit wheat varieties.


Asunto(s)
Harina , Gliadina , Gliadina/química , Pan , Triticum/química , Glútenes/química
14.
Nat Commun ; 14(1): 3345, 2023 06 08.
Artículo en Inglés | MEDLINE | ID: mdl-37291094

RESUMEN

Delivering genes to and across the brain vasculature efficiently and specifically across species remains a critical challenge for addressing neurological diseases. We have evolved adeno-associated virus (AAV9) capsids into vectors that transduce brain endothelial cells specifically and efficiently following systemic administration in wild-type mice with diverse genetic backgrounds, and in rats. These AAVs also exhibit superior transduction of the CNS across non-human primates (marmosets and rhesus macaques), and in ex vivo human brain slices, although the endothelial tropism is not conserved across species. The capsid modifications translate from AAV9 to other serotypes such as AAV1 and AAV-DJ, enabling serotype switching for sequential AAV administration in mice. We demonstrate that the endothelial-specific mouse capsids can be used to genetically engineer the blood-brain barrier by transforming the mouse brain vasculature into a functional biofactory. We apply this approach to Hevin knockout mice, where AAV-X1-mediated ectopic expression of the synaptogenic protein Sparcl1/Hevin in brain endothelial cells rescued synaptic deficits.


Asunto(s)
Células Endoteliales , Roedores , Ratones , Ratas , Animales , Células Endoteliales/metabolismo , Roedores/genética , Macaca mulatta/genética , Encéfalo/metabolismo , Tropismo/genética , Ratones Noqueados , Dependovirus/metabolismo , Vectores Genéticos/genética , Transducción Genética , Proteínas de Unión al Calcio/metabolismo , Proteínas de la Matriz Extracelular/genética
15.
Sci Adv ; 9(16): eadg6618, 2023 04 21.
Artículo en Inglés | MEDLINE | ID: mdl-37075114

RESUMEN

The blood-brain barrier (BBB) presents a major challenge for delivering large molecules to study and treat the central nervous system. This is due in part to the scarcity of targets known to mediate BBB crossing. To identify novel targets, we leverage a panel of adeno-associated viruses (AAVs) previously identified through mechanism-agnostic directed evolution for improved BBB transcytosis. Screening potential cognate receptors for enhanced BBB crossing, we identify two targets: murine-restricted LY6C1 and widely conserved carbonic anhydrase IV (CA-IV). We apply AlphaFold-based in silico methods to generate capsid-receptor binding models to predict the affinity of AAVs for these identified receptors. Demonstrating how these tools can unlock target-focused engineering strategies, we create an enhanced LY6C1-binding vector, AAV-PHP.eC, that, unlike our prior PHP.eB, also works in Ly6a-deficient mouse strains such as BALB/cJ. Combined with structural insights from computational modeling, the identification of primate-conserved CA-IV enables the design of more specific and potent human brain-penetrant chemicals and biologicals, including gene delivery vectors.


Asunto(s)
Barrera Hematoencefálica , Anhidrasa Carbónica IV , Ratones , Humanos , Animales , Barrera Hematoencefálica/metabolismo , Anhidrasa Carbónica IV/genética , Anhidrasa Carbónica IV/metabolismo , Encéfalo/metabolismo , Técnicas de Transferencia de Gen , Primates/genética , Dependovirus/genética , Dependovirus/metabolismo
16.
Res Sq ; 2023 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-36789432

RESUMEN

Adeno-associated viruses (AAVs) promise robust gene delivery to the brain through non-invasive, intravenous delivery. However, unlike in rodents, few neurotropic AAVs efficiently cross the blood-brain barrier in non-human primates (NHPs). Here we describe AAV.CAP-Mac, an engineered variant identified by screening in adult marmosets and newborn macaques with improved efficiency in the brain of multiple NHP species: marmoset, rhesus macaque, and green monkey. CAP-Mac is neuron-biased in infant Old World primates, exhibits broad tropism in adult rhesus macaques, and is vasculature-biased in adult marmosets. We demonstrate applications of a single, intravenous dose of CAP-Mac to deliver (1) functional GCaMP for ex vivo calcium imaging across multiple brain areas, and (2) a cocktail of fluorescent reporters for Brainbow-like labeling throughout the macaque brain, circumventing the need for germline manipulations in Old World primates. Given its capabilities for systemic gene transfer in NHPs, CAP-Mac promises to help unlock non-invasive access to the brain.

17.
bioRxiv ; 2023 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-36711773

RESUMEN

Delivering genes to and across the brain vasculature efficiently and specifically across species remains a critical challenge for addressing neurological diseases. We have evolved adeno-associated virus (AAV9) capsids into vectors that transduce brain endothelial cells specifically and efficiently following systemic administration in wild-type mice with diverse genetic backgrounds and rats. These AAVs also exhibit superior transduction of the CNS across non-human primates (marmosets and rhesus macaques), and ex vivo human brain slices although the endothelial tropism is not conserved across species. The capsid modifications translate from AAV9 to other serotypes such as AAV1 and AAV-DJ, enabling serotype switching for sequential AAV administration in mice. We demonstrate that the endothelial specific mouse capsids can be used to genetically engineer the blood-brain barrier by transforming the mouse brain vasculature into a functional biofactory. Vasculature-secreted Hevin (a synaptogenic protein) rescued synaptic deficits in a mouse model.

18.
ACS Omega ; 8(2): 2723-2732, 2023 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-36687026

RESUMEN

CuO x /TiO2 co-photocatalysts with various Cu loading contents were synthesized by an impregnation method, and their photocatalytic activities were evaluated by photodegradation of organic pollutants under visible light illumination. The as-prepared CuO x /TiO2 composites exhibited a unique structure, in which CuO x clusters with about 2-3 nm nanocrystals were uniformly distributed on the TiO2 cube. The mesoporous Ti3+/TiO2 substrate with a uniform pore structure greatly improved the uniformity of the loaded Cu, wherein Ti3+ acted as a reducing agent for reducing Cu2+ to Cu+ and Cu0. The reversible process of the Cu species between Cu+ and Cu0 markedly enhanced the photocatalytic activity of the CuO x /TiO2 co-photocatalyst, by promoting the transfer of photogenerated electrons and suppressing the recombination of photogenerated electron and hole pairs. The synergistic effect between CuO x and TiO2 also played an important role in enhancing the photocatalytic activity of the CuO x /TiO2 co-photocatalyst. The results indicated that CuO x /TiO2-1 had the highest photocatalytic efficiency, which was 1.5 times higher than that of the commercial nano-TiO2 P25 under visible light, and demonstrated a good stability even after five recycles. This structural design and the valence control strategy for the Cu atom provide an idea that facilitates the utilization of visible light and the improvement of the photocatalytic activity of TiO2, promoting the practical application of the TiO2 photocatalyst.

19.
Nat Biotechnol ; 41(9): 1272-1286, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-36702899

RESUMEN

A barrier to advancing engineered adeno-associated viral vectors (AAVs) for precision access to cell subtypes is a lack of high-throughput, high-resolution assays to characterize in vivo transduction profiles. In this study, we developed an ultrasensitive, sequential fluorescence in situ hybridization (USeqFISH) method for spatial transcriptomic profiling of endogenous and viral RNA with a short barcode in intact tissue volumes by integrating hydrogel-based tissue clearing, enhanced signal amplification and multiplexing using sequential labeling. Using USeqFISH, we investigated the transduction and cell subtype tropisms across mouse brain regions of six systemic AAVs, including AAV-PHP.AX, a new variant that transduces robustly and efficiently across neurons and astrocytes. Here we reveal distinct cell subtype biases of each AAV variant, including a bias of AAV-PHP.N toward excitatory neurons. USeqFISH also enables profiling of pooled regulatory cargos, as we show for a 13-variant pool of microRNA target sites in AAV genomes. Lastly, we demonstrate potential applications of USeqFISH for in situ AAV profiling and multimodal single-cell analysis in non-human primates.


Asunto(s)
Técnicas de Transferencia de Gen , Transcriptoma , Ratones , Animales , Transducción Genética , Hibridación Fluorescente in Situ , Transcriptoma/genética , Vectores Genéticos/genética , Tropismo/genética , Dependovirus/genética , Tropismo Viral/genética
20.
Chemosphere ; 313: 137650, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36574788

RESUMEN

Heavy metals such as cadmium (Cd) in farmland soil not only affect crop production, but also endanger human health through the food chain. Rice is the main food crop with the strongest ability to absorb Cd, remediation techniques to reduce soil uptake and grain accumulation of Cd are urgently required, for which the application of foliar spraying seems to be a convenient and auspicious method. This study clarified the effects of nitrogen (N), zinc (Zn), 24-epibrassionlide (EBL) and their combined application on the growth performance and physiological characteristics of Cd and Zn in rice plants under Cd stress. Experimental results showed that N and its combination with Zn, EBL treatments promoted rice growth and yield, especially raised the yield level by 81.12% under N + EBL treatment. Additionally, three EBL treatments (EBL, N + EBL, Zn + EBL) significantly reduced the TF values of Cd in TF stems-grains, TF leaves-grains and TF glumes-grains by 42.70%, 43.67% and 50.33%, while the EF soil-roots under Zn and N + Zn treatments was the lowest, which decreased by 55.39% and 57.71%, respectively. Further, the application of N, Zn, EBL and their combined treatments significantly increased glutathione (GSH) and phytochelatins (PCs) content as well as enhanced Cd distribute into cell walls of rice shoots and roots by 15.18% and 13.20%, respectively. In addition, N, Zn, EBL and their combined application increased Zn concentration, free amino acid and glutelin content, and decreased the Cd accumulation in albumin, glutelin and globulin, thus lowered Cd concentration in grains by 27.55%, 58.29% and 51.56%, respectively. These results comprehensive suggest that the possibility of N management combined with Zn or EBL application for maintaining high yield and alleviating Cd stress by regulating the absorption and remobilization process under mild stress.


Asunto(s)
Oryza , Contaminantes del Suelo , Humanos , Zinc/análisis , Cadmio/análisis , Oryza/química , Contaminantes del Suelo/análisis , Suelo/química
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