RESUMO
Glucans are major biomaterials on the earth, with α-(1â4)-glucans (i. e., amylose) and ß-(1â4)-glucans (i. e., cellulose) being the most abundant ones, which are relevant to energy storage and structural function, respectively. Interestingly, (1â4)-glucans with alternate α/ß-linkages, namely herewith amycellulose, have never been disclosed in nature. Here we report a robust glycosylation protocol for the stereoselective construction of the 1,2-cis-α- and 1,2-trans-ß-glucosidic linkages, which employs an optimal combination of glycosyl N-phenyltrifluoroacetimidates as donors, TMSNTf2 as promoter, CH2 Cl2 /nitrile or CH2 Cl2 /THF as solvents. A broad substrate scope has been demonstrated by coupling five imidate donors with eight glycosyl acceptors, in which most of the glycosylations lead to high yield and exclusively 1,2-cis-α- or 1,2-trans-ß-selectivity. Applying this glycosylation protocol and with an iterative manner, the unprecedented α/ß-alternate (1â4)-glucans up to a 16-mer have been synthesized. Differently from amylose, that adopts a compact helicoidal arrangement, the synthetic amycellulose features an extended ribbon-like conformation, comparable to the extended shape of cellulose.
RESUMO
INTRODUCTION: MicroRNAs (miRNAs)-a class of small endogenous non-coding RNAs-are widely involved in post-transcriptional gene regulation of numerous physiological processes. High-throughput sequencing revealed that the miR-192 expression level appeared to be significantly higher in the blood exosomes of sows at early gestation than that in non-pregnant sows. Furthermore, miR-192 was hypothesized to have a regulatory role in embryo implantation; however, the target genes involved in exerting the regulatory function of miR-192 required further elucidation. METHODS: In the present study, potential target genes of miR-192 in porcine endometrial epithelial cells (PEECs) were identified through biotin-labeled miRNA pull-down; functional and pathway enrichment analysis was performed via gene ontology analysis and Kyoto Encyclopedia of Genes and Genomes pathway enrichment. Bioinformatic analyses were concurrently used to predict the potential target genes associated with sow embryo implantation. In addition, double luciferase reporter vectors, reverse transcriptase-quantitative polymerase chain reaction (RT-qPCR), and Western blot were performed to verify the targeting and regulatory roles of the abovementioned target genes. RESULTS: A total of 1688 differentially expressed mRNAs were identified via miRNA pull-down. Through RT-qPCR, the accuracy of the sequencing data was verified. In the bioinformatics analysis, potential target genes of miR-192 appeared to form a dense inter-regulatory network and regulated multiple signaling pathways, such as metabolic pathways and the PI3K-Akt, MAPKs, and mTOR signaling pathways, that are relevant to the mammalian embryo implantation process. In addition, CSK (C-terminal Src kinase) and YY1 (Yin-Yang-1) were predicted to be potential candidates, and we validated that miR-192 directly targets and suppresses the expression of the CSK and YY1 genes. CONCLUSION: We screened 1688 potential target genes of miR-192 were screened, and CSK and YY1 were identified as miR-192 target genes. The outcomes of the present study provide novel insights into the regulatory mechanism of porcine embryo implantation and the identification of miRNA target genes.
Assuntos
Endométrio , MicroRNAs , Animais , Feminino , Células Epiteliais/metabolismo , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Mamíferos/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , RNA Mensageiro/genética , Transdução de Sinais/genética , Suínos/genética , Endométrio/metabolismoRESUMO
DNA nanotubes with prescribed geometry could allow for nanomaterial organization with designed optical or electrical function. As one of the dominating driving forces for DNA nanotube assembly, intrinsic curvature and twist of building blocks can be induced by bending deformation and twisting deformation. However, it is still unknown that how bending and twisting design on nanoscale building blocks affects the geometry of DNA tubes with micrometer length. Here, through targeted base pair deletion or insertion, the amount of bending deformation in building blocks is modulated by length gradient and the amount of twisting deformation is modulated by average twist density. This work systematically explores the independent effect and synergistic effect of two types of deformation on tube geometry, including diameter, chirality, and helical angles, via a streptavidin-labeling technique. The design rules enable the construction of DNA nanotubes with prescribed chirality and tailored diameters.
Assuntos
DNARESUMO
MiRNAs-containing extracellular vesicles (EVs) possess the unique function of mediating intercellular communication and participating in many biological processes such as post-transcriptional gene regulation of embryo implantation and placental development. In the present study, Illumina small-RNA sequencing was used to identify differentially expressed (DE) miRNAs in serum EVs of pregnant (P) and non-pregnant (NP) Kazakh sheep at Day 17 from mating. The specifically and differentially expressed miRNAs at early pregnancy in sheep were verified by using RT-PCR. The target genes of DE miRNAs were predicted by bioinformatics software, and the functional and pathway enrichment analysis was performed on Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) terms. A total of 562 miRNAs (210 novel miRNAs) were identified by sequencing, of which 57 miRNAs were differentially expressed, 49 were up-regulated, 8 were down-regulated and 22 novel miRNAs were specifically expressed in the pregnant sheep. Eight highly expressed known miRNA (miR-378-3p, miR-320-3p, miR-22-3p, let-7b, miR-423-3p, miR-221, miR-296-3p, miR-147-3p) in pregnant group were down-regulated in the control group. miRNAs-containing pregnancy-related terms and regulatory pathways regulation were enriched using both GO and KEGG analyses. Moreover, we also envisioned a miRNA-mRNA interaction network to understand the function of miRNAs involved in the early pregnancy serum regulatory network. The results of RT-PCR verification confirmed the reliability of small-RNA sequencing. Among them, miR-22-3p and miR-378-3p were significantly differentially expressed (DE) between pregnant sheep and non-pregnant group (p < 0.01). The site at which oar-miR-22-3p binds MAPK3 was determined with a dual-luciferase system. This is the first integrated analysis of the expression profiles of EV-miRNAs and their targets during early pregnancy in ewes. These data identify key miRNAs that influence the implantation of sheep in the early stage of pregnancy, and provide theoretical basis for further molecular regulatory mechanisms research.
Assuntos
Vesículas Extracelulares/metabolismo , MicroRNAs/metabolismo , Prenhez/sangue , Animais , Vesículas Extracelulares/genética , Feminino , Perfilação da Expressão Gênica/veterinária , MicroRNAs/genética , Gravidez , Prenhez/metabolismo , Carneiro DomésticoRESUMO
Insects utilize diverse families of ion channels to respond to environmental cues and control mating, feeding, and the response to threats. Although degenerin/epithelial sodium channels (DEG/ENaC) represent one of the largest families of ion channels in Drosophila melanogaster, the physiological functions of these proteins are still poorly understood. We found that the DEG/ENaC channel ppk23 is expressed in a subpopulation of sexually dimorphic gustatory-like chemosensory bristles that are distinct from those expressing feeding-related gustatory receptors. Disrupting ppk23 or inhibiting activity of ppk23-expressing neurons did not alter gustatory responses. Instead, blocking ppk23-positive neurons or mutating the ppk23 gene delayed the initiation and reduced the intensity of male courtship. Furthermore, mutations in ppk23 altered the behavioral response of males to the female-specific aphrodisiac pheromone 7(Z), 11(Z)-Heptacosadiene. Together, these data indicate that ppk23 and the cells expressing it play an important role in the peripheral sensory system that determines sexual behavior in Drosophila.
Assuntos
Corte , Proteínas de Drosophila , Drosophila melanogaster , Canais Iônicos , Comportamento Sexual Animal , Alcadienos/farmacologia , Animais , Animais Geneticamente Modificados , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/fisiologia , Feminino , Regulação da Expressão Gênica , Canais Iônicos/genética , Canais Iônicos/metabolismo , Masculino , Mutação , Neurônios/metabolismo , Comportamento Sexual Animal/efeitos dos fármacos , Comportamento Sexual Animal/fisiologia , Percepção Gustatória/genéticaRESUMO
Monitoring heavy metal concentrations in soils is central to assessing agricultural production safety. Satellite observations permit inferring concentrations from spectrum, thereby contributing to the prevention and control of soil heavy metal pollution. However, heavy metals exhibit weak spectral responses, particularly at low and medium concentrations, and are predominantly influenced by other soil components. Machine learning (ML)-driven modelling can produce predictions but lacks interpretability. Here, we present an interpretable ML framework for concentration quantification modelling and investigated the contributions of spectral and environmental factors-pH and organic carbon-to the estimation of metals with multiple concentration gradients, as analysed through SHAP (SHapley Additive exPlanations) data derived from four learning-based scenarios. The results indicated that scenarios SHC (spectral, pH, and organic carbon) and SH (spectral and pH) were the most optimal for chromium (Cr) [RPD = 1.42, Adj R2 = 0.62], and cadmium (Cd) [RPD = 1.80, Adj R2 = 0.80]. Under environmental constraints, the spectral predictability for Cr and Cd was improved by 67 % and 87 %, respectively. We concluded that interpretable modelling, utilising both spectral and soil environmental factors, holds significant potential for estimating heavy metals across concentration gradients. It is recommended that samples with higher organic carbon content and lower pH be selected to enhance Cr and Cd predictions. An advanced grasp of interpretable predictions facilitates earlier warning of heavy metal contamination and guides the formulation of robust sampling strategies.
RESUMO
Voltage-gated sodium (Nav) channels sense membrane potential and drive cellular electrical activity. The deathstalker scorpion α-toxin LqhαIT exerts a strong action potential prolonging effect on Nav channels. To elucidate the mechanism of action of LqhαIT, we determined a 3.9 Å cryoelectron microscopy (cryo-EM) structure of LqhαIT in complex with the Nav channel from Periplaneta americana (NavPas). We found that LqhαIT binds to voltage sensor domain 4 and traps it in an "S4 down" conformation. The functionally essential C-terminal epitope of LqhαIT forms an extensive interface with the glycan scaffold linked to Asn330 of NavPas that augments a small protein-protein interface between NavPas and LqhαIT. A combination of molecular dynamics simulations, structural comparisons, and prior mutagenesis experiments demonstrates the functional importance of this toxin-glycan interaction. These findings establish a structural basis for the specificity achieved by scorpion α-toxins and reveal the conserved glycan as an essential component of the toxin-binding epitope.
RESUMO
Widespread soil contamination endangers public health and undermines global attempts to achieve the United Nations Sustainable Development Goals. Due to the lack of relevant studies and low precision of spaceborne spectroscopy, estimating soil heavy metal concentrations is challenging. In this study, we developed a coupled retrieval to qualify the heavy metal nickel (Ni) concentration in agricultural soil from spaceborne hyperspectral imagery. The retrieval couples spectral feature extraction from multi-scale discrete wavelet transform (DWT) and dimension reduction (DR), optimal band combination algorithm to five machine learning retrieval models using tree-based ensemble learning, neural network-based, and kernel-based. The comparison between the retrievals and Ni measurements shows that the DWT combined with t-distributed stochastic neighbor embedding (tSNE) coupled extreme gradient boosting (XGboost) retrieval model exhibited the best prediction for the validation dataset. Moreover, due to the integration of six statistical indicators of model performance and the fitted slope of the regression line, the retrieval framework can produce more robust and accurate predictions than those that rely on correlation coefficients. The demonstrated potential of spaceborne hyperspectral remote sensing to provide accurate quantitative measurements of soil heavy metal concentrations will serve as a reference for agricultural plot applications worldwide.
RESUMO
OBJECTIVE: To evaluate 99mtechnetium-three polyethylene glycol spacers-arginine-glycine-aspartic acid (99mTc-3PRGD2) single-photon emission computed tomography (SPECT)/computed tomography (CT) imaging for diagnosing lymph node metastasis of primary malignant lung neoplasms. MATERIALS AND METHODS: We prospectively enrolled 26 patients with primary malignant lung tumors who underwent 99mTc-3PRGD2 SPECT/CT and 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)/CT imaging. Both imaging methods were analyzed in qualitative (visual dichotomous and 5-point grades for lymph nodes and lung tumors, respectively) and semi-quantitative (maximum tissue-to-background radioactive count) manners for the lymph nodes and lung tumors. The performance of the differentiation of lymph nodes with and without metastasis was determined at the per-lymph node station and per-patient levels using histopathological results as the reference standard. RESULTS: Total 42 stations had metastatic lymph nodes and 136 stations had benign lymph nodes. The differences between metastatic and benign lymph nodes in the visual qualitative and semiquantitative analyses of 99mTc-3PRGD2 SPECT/CT and 18F-FDG PET/CT were statistically significant (all P < 0.001). The area under the receiver operating characteristic curve (AUC) in the semi-quantitative analysis of 99mTc-3PRGD2 SPECT/CT was 0.908 (95% confidence interval [CI], 0.851-0.966), and the sensitivity, specificity, positive predictive value, and negative predictive value were 0.86 (36/42), 0.88 (120/136), 0.69 (36/52), and 0.95 (120/126), respectively. Among the 26 patients (including two patients each with two lung tumors), 15 had pathologically confirmed lymph node metastasis. The difference between primary lung lesions in patients with and without lymph node metastasis was statistically significant only in the semi-quantitative analysis of 99mTc-3PRGD2 SPECT/CT (P = 0.007), with an AUC of 0.807 (95% CI, 0.641-0.974). CONCLUSION: 99mTc-3PRGD2 SPECT/CT imaging may notably perform in the direct diagnosis of lymph node metastasis of primary malignant lung tumors and indirectly predict the presence of lymph node metastasis through uptake in the primary lesions.
Assuntos
Neoplasias Pulmonares , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Fluordesoxiglucose F18 , Metástase Linfática/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Neoplasias Pulmonares/diagnóstico por imagem , Compostos RadiofarmacêuticosRESUMO
Extrusion speed has a significant influence on the extrusion temperature, microstructure and mechanical properties of the material in the repetitive continuous extrusion forming (RCEF) process. In this work, the mechanical properties of Al2024 were improved by adjusting the speed (with a general range of 2-10 rpm) of repetitive continuous extrusion and applying subsequent heat treatment. During the RCEF process, an increase in the extrusion speed from 4 to 8 rpm was found to increase the extrusion temperature and then enhance the solid solution function. The grain size was affected by the combined effect of deformation speed and its induced temperature. A high-strength Al2024 (ultimate tensile strength of 497.6 MPa) with good elongation (12.93%) was obtained by increasing the extrusion speed and conducting solid solution and artificial aging treatments. The main strengthening mechanisms could be attributed to finer grain size and a larger amount of S (Al2CuMg) precipitates.
RESUMO
The study aimed to investigate the associations between different types of screen time (ST) and anxiety and depressive symptoms in college students during the Coronavirus disease 2019 (COVID-19) outbreak in Shanghai, China; the potential mediation role of sleep quality was also examined. A total of 1,550 college students completed an online survey in May 2022. ST, Self-rating Anxiety Scale (SAS) score, Self-rating Depression Scale (SDS) score, Pittsburgh Sleep Quality Index (PSQI) score, and physical activity were self-reported. Multiple linear regression and mediation analysis were conducted. The results showed that more time spent in TV/movie viewing (>2 h/day) and recreational reading (>1 h/day) was associated with higher levels of anxiety, while more time spent in online social media (>2 h/day) was associated with a higher level of depressive symptoms. In contrast, time spent in online social media (1-2 h/day) was associated with a lower level of anxiety. Meanwhile, recreational reading (2-3 h/day) had a significant indirect effect on anxiety and depressive symptoms through sleep quality. During the COVID-19 outbreak, the associations of ST with anxiety and depressive symptoms varied by the type of screen viewing in college students. The associations of slightly excessive time spent on recreational reading with higher levels of anxiety and depressive symptoms were partially mediated by sleep quality.
RESUMO
The accurate estimation of leaf chlorophyll content (LCC) is a significant foundation in assessing litchi photosynthetic activity and possible nutrient status. Hyperspectral remote sensing data have been widely used in agricultural quantitative monitoring research for the non-destructive assessment of LCC. Variable selection approaches are crucial for analyzing high-dimensional datasets due to the high danger of overfitting, time-intensiveness, or substantial computational requirements. In this study, the performance of five machine learning regression algorithms (MLRAs) was investigated based on the hyperspectral fractional order derivative (FOD) reflection of 298 leaves together with the variable combination population analysis (VCPA)-genetic algorithm (GA) hybrid strategy in estimating the LCC of Litchi. The results showed that the correlation coefficient (r) between the 0.8-order derivative spectrum and LCC had the highest correlation coefficients (r = 0.9179, p < 0.01). The VCPA-GA hybrid strategy fully utilizes VCPA and GA while compensating for their limitations based on a large number of variables. Moreover, the model was developed using the selected 14 sensitive bands from 0.8-order hyperspectral reflectance data with the lowest root mean square error in prediction (RMSEP = 5.04 µg·cm-2). Compared with the five MLRAs, validation results confirmed that the ridge regression (RR) algorithm derived from the 0.2 order was the most effective for estimating the LCC with the coefficient of determination (R2 = 0.88), mean absolute error (MAE = 3.40 µg·cm-2), root mean square error (RMSE = 4.23 µg·cm-2), and ratio of performance to inter-quartile distance (RPIQ = 3.59). This study indicates that a hybrid variable selection strategy (VCPA-GA) and MLRAs are very effective in retrieving the LCC through hyperspectral reflectance at the leaf scale. The proposed methods could further provide some scientific basis for the hyperspectral remote sensing band setting of different platforms, such as an unmanned aerial vehicle (UAV) and satellite.
RESUMO
Background: We aimed to investigate the diagnostic value of dynamic 2-deoxy-2-[18F]-fluoro-D-glucose positron emission tomography-computed tomography in non-small cell lung cancer and fluoro-D-glucose hypermetabolic lymph nodes. Methods: Patients who made an active appointment for positron emission tomography-computed tomography were randomly enrolled by referring to previous imaging data and clinical information. Finally, 34 histopathologically confirmed non-small cell lung cancers (18 adenocarcinoma and 16 squamous cell carcinoma cases) were prospectively studied using dynamic and static 2-deoxy-2-[18F]-fluoro-D-glucose positron emission tomography-computed tomography imaging (the diagnostic study has not yet been registered on a clinical trial platform). In dynamic positron emission tomography images, a volume of interest, defined by the thoracic aorta, was selected for estimating the arterial input function. Patlak and irreversible two-tissue compartment model analyses were performed based on the pixel points to obtain first-order characteristic kinetic parameters for each lesion and hypermetabolic lymph node. The first-order characteristic kinetic parameters were obtained based on the basic data of dynamic positron emission tomography images in the corresponding model and the lesion delineation of region-of-interest based on computed tomography images, such as V_Median (the median gray intensity of V), k3_Entropy, VB_Entropy, K1_Uniformity, and ki_Uniformity. The first-order characteristic kinetic parameters were also modeled by logistic regression for the differential diagnosis of non-small cell lung cancer and hypermetabolic lymph nodes. Maximum and mean standard uptake values (SUVmax and SUVmean, respectively) were obtained from static positron emission tomography images. The diagnostic efficacy of the parameters was evaluated using the receiver operating characteristic curve and the DeLong test. Results: There was a significant difference in the V_Median values of adenocarcinoma and squamous cell carcinoma. The regression models for K1, k3, and V provided good predictions of adenocarcinoma and squamous cell carcinoma typology. Significant differences were observed in k3_Entropy, VB_Entropy, K1_Uniformity, and ki_Uniformity between benign and malignant lymph nodes. The regression model of Ki, VB, and k3 could make a good prediction for identifying benign and malignant lymph nodes. Conclusions: Dynamic 2-deoxy-2-[18F]-fluoro-D-glucose positron emission tomography-computed tomography imaging showed high diagnostic value in the staging of non-small cell lung cancer and fluoro-D-glucose hypermetabolic lymph nodes, and can be of great use in non-small cell lung cancer lymph node staging and surgical decision-making.
RESUMO
Copy number variants (CNVs) that delete or duplicate 30 genes within the 16p11.2 genomic region give rise to a range of neurodevelopmental phenotypes with high penetrance in humans. Despite the identification of this small region, the mechanisms by which 16p11.2 CNVs lead to disease are unclear. Relevant models, such as human cortical organoids (hCOs), are needed to understand the human-specific mechanisms of neurodevelopmental disease. We generated hCOs from 17 patients and controls, profiling 167,958 cells with single-cell RNA-sequencing analysis, which revealed neuronal-specific differential expression of genes outside the 16p11.2 region that are related to cell-cell adhesion, neuronal projection growth, and neurodevelopmental disorders. Furthermore, 16p11.2 deletion syndrome organoids exhibited reduced mRNA and protein levels of RBFOX1, a gene that can also harbor CNVs linked to neurodevelopmental phenotypes. We found that the genes previously shown to be regulated by RBFOX1 are also perturbed in organoids from patients with the 16p11.2 deletion syndrome and thus identified a novel link between independent CNVs associated with neuronal development and autism. Overall, this work suggests convergent signaling, which indicates the possibility of a common therapeutic mechanism across multiple rare neuronal diseases.
Assuntos
Deleção Cromossômica , Variações do Número de Cópias de DNA , Humanos , Variações do Número de Cópias de DNA/genética , Encéfalo , Fenótipo , Organoides , Fatores de Processamento de RNA/genéticaRESUMO
Although many animal species sense gravity for spatial orientation, the molecular bases remain uncertain. Therefore, we studied Drosophila melanogaster, which possess an inherent upward movement against gravity-negative geotaxis. Negative geotaxis requires Johnston's organ, a mechanosensory structure located in the antenna that also detects near-field sound. Because channels of the transient receptor potential (TRP) superfamily can contribute to mechanosensory signaling, we asked whether they are important for negative geotaxis. We identified distinct expression patterns for 5 TRP genes; the TRPV genes nanchung and inactive were present in most Johnston's organ neurons, the TRPN gene nompC and the TRPA gene painless were localized to 2 subpopulations of neurons, and the TRPA gene pyrexia was expressed in cap cells that may interact with the neurons. Likewise, mutating specific TRP genes produced distinct phenotypes, disrupting negative geotaxis (painless and pyrexia), hearing (nompC), or both (nanchung and inactive). Our genetic, physiological and behavioral data indicate that the sensory component of negative geotaxis involves multiple TRP genes. The results also distinguish between different mechanosensory modalities and set the stage for understanding how TRP channels contribute to mechanosensation.
Assuntos
Estruturas Animais/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Sensação Gravitacional/fisiologia , Audição/fisiologia , Canais de Potencial de Receptor Transitório/metabolismo , Estruturas Animais/citologia , Animais , Comportamento Animal , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Fenômenos Eletrofisiológicos , Regulação da Expressão Gênica , Genes de Insetos , Gravitropismo , Mutação/genética , Postura , Rotação , Canais de Potencial de Receptor Transitório/genéticaRESUMO
Highly integrated transparent electronic systems are experiencing significant thermal bottlenecks due to the rapid growth of transparent electronics and the lack of suitable transparent thermal management solutions. Therefore, transparent thermal management materials are highly desirable in modern transparent electronics. Based on the phase change properties of polyethylene glycol (PEG) and the encapsulable properties of epoxy resin (EP), we synthesize a biphasically and reversibly transparent PEG/EP composite for thermal energy storage (TPE-TES). Energy-driven structural rearrangements in cross-linked networks are responsible for the high transparency with practical thickness. According to SEM and TEM investigations, PEG and EP achieve submicron phase dispersion, while TPE-TES forms a smooth and continuous surface that suppresses diffuse reflections and contributes to improved visible light penetration. The unique combination of phase change and optical transparency gives TPE-TES the ability to regulate thermal storage, rapid temperature change, and spatial temperature uniformity of transparent electronics. Due to its flexibility, stability, and processability, TPE-TES is also suitable and ideal as thin surface coating films or thick transparent flexible substrates for a wide range of applications in the integration of electronic devices.
RESUMO
To explore the effects of iminodisuccinic acid (a chelating agent) on maize (Zea mays L.) seed germination under lead (Pb) stress, we comparatively analyzed the effects of applying different concentrations of iminodisuccinic acid (0, 5, 20, and 100 mmol·dm-3) and combined an addition of exogenous substances regulating reactive oxygen species production on maize seed germination, seedling growth, H2O2 content, NADPH oxidase activity, and antioxidant enzyme activities under Pb-stressed and Pb-free conditions. Iminodisuccinic acid (100 mmol·dm-3) significantly delayed seed germination under normal germination conditions and alleviated the inhibitory effects of Pb stress (20 mmol·dm-3) on seed germination. Under normal conditions (without Pb stress), the iminodisuccinic acid-induced inhibition of seed germination was enhanced by treatment with dimethylthiourea (a specific scavenger of reactive oxygen species) or diphenyleneiodonium chloride (a specific inhibitor of NADPH oxidase), but diminished by treatment with H2O2, CaCl2, diethyldithiocarbamic acid (a specific inhibitor of superoxide dismutase), or aminotriazole (a specific inhibitor of catalase). Under Pb stress, iminodisuccinic acid partially eliminated the excessive H2O2 accumulation, improved superoxide dismutase and catalase activity, and weakened the high NADPH oxidase activity. In addition, Ca2+ chelation may be essential for maintaining the reactive oxygen species' balance and improving seed germination and seedling growth by iminodisuccinic acid supplementation in maize under Pb stress. The proposed iminodisuccinic acid supplementation-based method improved maize seed germination in Pb-polluted soil.
RESUMO
Ovulation rate is an extremely important factor affecting litter size in sows. It differs greatly among pig breeds with different genetic backgrounds. Long non-coding RNAs (lncRNAs) can regulate follicle development, granulosa cell growth, and hormone secretion, which in turn can affect sow litter size. In this study, we identified 3554 lncRNAs and 25,491 mRNAs in M2 follicles of Meishan and Duroc sows. The lncRNA sequence and open reading frame lengths were shorter than mRNAs, and lncRNAs had fewer exons, were less abundant, and more conserved than protein-coding RNAs. Furthermore, 201 lncRNAs were differentially expressed (DE) between breeds, and quantitative trait loci analysis of DE lncRNAs were performed. A total of 127 DE lncRNAs were identified in 119 reproduction trait-related loci. In addition, the potential target genes of lncRNAs in cis or trans configurations were predicted. Gene ontology and Kyoto Encyclopedia of Genes and Genomes pathway analysis revealed that some potential target genes were involved in follicular development and hormone secretion-related biological processes or pathways, such as progesterone biosynthetic process, estrogen metabolic process, ovarian steroidogenesis, and PI3K-Akt signaling pathway. Furthermore, we also screened 19 differentially expressed lncRNAs in the PI3K-Akt signaling pathway as candidates. This study provides new insights into the roles of lncRNAs in follicular growth and development in pigs.
Assuntos
Folículo Ovariano/crescimento & desenvolvimento , RNA Longo não Codificante/metabolismo , Transcriptoma , Animais , Éxons , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Ontologia Genética , Redes Reguladoras de Genes , Células da Granulosa/metabolismo , MicroRNAs/genética , Biologia Molecular , Folículo Ovariano/metabolismo , Ovário , Fosfatidilinositol 3-Quinases/metabolismo , Progesterona/metabolismo , Locos de Características Quantitativas , RNA/metabolismo , RNA Mensageiro/genética , SuínosRESUMO
Beta-pompilidotoxin (ß-PMTX) is a 13-amino acid wasp venom peptide that activates human neuronal sodium channel NaV1.1 with weak activity (40% activation at 3.3 µM of ß-PMTX). Through rational design of ß-PMTX analogs, we have identified peptides with significantly improved activity on human NaV1.1 (1170% activation at 3.3 µM of peptide 18). The underlying structure-activity relationship suggests importance of charge interactions (from residue Lys-3) and lipophilic interactions (from residue Phe-7 and Ser-11). Three top-ranked analogs showed parallel activity improvement for other neuronal sodium channels (human NaV1.2/1.3/1.6/1.7) but not muscular subtypes (NaV1.4/1.5). Finally, we found that analog 16 could partially rescue the pharmacological block imposed by NaV1.1/1.3 selective inhibitor ICA-121431 in cultured mouse cortical GABAergic neurons, demonstrating an activating effect of this peptide on native neuronal sodium channels and its potential utility as a neuropharmacological tool.
RESUMO
Circular RNAs (circRNAs) are a newly discovered class of endogenous non-coding RNAs that play an important role in growth and development by regulating gene expression and participating in a variety of biological processes. However, the role of circRNAs in porcine follicles remains unclear. Therefore, this study examined middle-sized ovarian follicles obtained from Meishan and Duroc sows at day 4 of the follicular phase. High-throughput RNA sequencing (RNA-seq) was utilized to construct circRNAs, and differential expression was identified. The findings were validated using reverse transcription PCR (RT-PCR) and DNA sequencing, GO and KEGG analyses were performed, and potential miRNA targets were identified. The RNA-seq identified a total of 15,866 circRNAs, with 244 differentially expressed in the Meishan relative to the Duroc (111 up-regulated and 133 down-regulated). The RT-PCR finding confirmed the RNA-seq results, and quantitative real-time PCR (qPCR) analysis examining a subset of the circRNAs showed that they are resistant to RNase R digestion. Bioinformatics analysis (GO and KEGG) showed that the host genes associated with the differentially expressed circRNAs are involved in reproduction and follicular development signaling pathways. Furthermore, many of the circRNAs were found to interact with miRNAs that are associated with follicular development. This study presents a new perspective for studying circRNAs and provides a valuable resource for further examination into the potential roles of circRNAs in porcine follicular development.