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Phosphorus (P) deficiency is one of the most critical factors for plant growth and productivity, including its inhibition of lateral root initiation. Auxin response factors (ARFs) play crucial roles in root development via auxin signaling mediated by genetic pathways. In this study, we found that the transcription factor ZmARF1 was associated with low inorganic phosphate (Pi) stress-related traits in maize. This superior root morphology and greater phosphate stress tolerance could be ascribed to the overexpression of ZmARF1. The knock out mutant zmarf1 had shorter primary roots, fewer root tip number, and lower root volume and surface area. Transcriptomic data indicate that ZmLBD1, a direct downstream target gene, is involved in lateral root development, which enhances phosphate starvation tolerance. A transcriptional activation assay revealed that ZmARF1 specifically binds to the GC-box motif in the promoter of ZmLBD1 and activates its expression. Moreover, ZmARF1 positively regulates the expression of ZmPHR1, ZmPHT1;2, and ZmPHO2, which are key transporters of Pi in maize. We propose that ZmARF1 promotes the transcription of ZmLBD1 to modulate lateral root development and Pi-starvation induced (PSI) genes to regulate phosphate mobilization and homeostasis under phosphorus starvation. In addition, ZmERF2 specifically binds to the ABRE motif of the promoter of ZmARF1 and represses its expression. Collectively, the findings of this study revealed that ZmARF1 is a pivotal factor that modulates root development and confers low-Pi stress tolerance through the transcriptional regulation of the biological function of ZmLBD1 and the expression of key Pi transport proteins.
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Fosfatos , Zea mays , Fosfatos/metabolismo , Fósforo/metabolismo , Ácidos Indolacéticos/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Raíces de Plantas , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismoRESUMEN
Circular RNAs (CircRNAs) play an important role in diverse biological processes; however, their origin and functions, especially in plants, remain largely unclear. Here, we used two maize (Zea mays) inbred lines, as well as 14 of their derivative RILs with different drought sensitivity, to systematically characterize 8,790 circRNAs in maize roots under well-watered (WW) and water-stress (WS) conditions. We found that a diverse set of circRNAs expressed at significantly higher levels under WS. Enhanced expression of circRNAs was associated with longer flanking introns and an enrichment of long interspersed nuclear element (LINE) retrotransposable elements. The epigenetic marks found at the back-splicing junctions of circRNA-producing genes were markedly different from canonical splicing, characterized by increased levels of H3K36me3/H3K4me1, as well as decreased levels of H3K9Ac/H3K27Ac. We found that genes expressing circRNAs are subject to relaxed selection. The significant enrichment of trait-associated sites along their genic regions suggested that genes giving rise to circRNAs were associated with plant survival rate under drought stress, implying that circRNAs play roles in plant drought responses. Furthermore, we found that overexpression of circMED16, one of the drought-responsive circRNAs, enhances drought tolerance in Arabidopsis (Arabidopsis thaliana). Our results provide a framework for understanding the intricate interplay of epigenetic modifications and how they contribute to the fine-tuning of circRNA expression under drought stress.
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The accurate construction of neural circuits requires the precise control of axon growth and guidance, which is regulated by multiple growth and guidance cues during early nervous system development. It is generally thought that the growth and guidance cues that control the major steps of axon development have been defined. Here, we describe cerebellin-1 (Cbln1) as a novel cue that controls diverse aspects of axon growth and guidance throughout the central nervous system (CNS) by experiments using mouse and chick embryos. Cbln1 has previously been shown to function in late neural development to influence synapse organization. Here, we find that Cbln1 has an essential role in early neural development. Cbln1 is expressed on the axons and growth cones of developing commissural neurons and functions in an autocrine manner to promote axon growth. Cbln1 is also expressed in intermediate target tissues and functions as an attractive guidance cue. We find that these functions of Cbln1 are mediated by neurexin-2 (Nrxn2), which functions as the Cbln1 receptor for axon growth and guidance. In addition to the developing spinal cord, we further show that Cbln1 functions in diverse parts of the CNS with major roles in cerebellar parallel fiber growth and retinal ganglion cell axon guidance. Despite the prevailing role of Cbln1 as a synaptic organizer, our study discovers a new and unexpected function for Cbln1 as a general axon growth and guidance cue throughout the nervous system.
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Axones , Cerebelo , Embrión de Pollo , Animales , Ratones , Axones/metabolismo , Cerebelo/metabolismo , Médula Espinal/metabolismo , Neuronas/metabolismo , Proteínas del Tejido Nervioso/genética , Precursores de Proteínas/metabolismoRESUMEN
KEY MESSAGE: Eight selected hotspots related to ear traits were identified from two maize-teosinte populations. Throughout the history of maize cultivation, ear-related traits have been selected. However, little is known about the specific genes involved in shaping these traits from their origins in the wild progenitor, teosinte, to the characteristics observed in modern maize. In this study, five ear traits (kernel row number [KRN], ear length [EL], kernel number per row [KNR], cob diameter [CD], and ear diameter [ED]) were investigated, and eight quantitative trait loci (QTL) hotspots were identified in two maize-teosinte populations. Notably, our findings revealed a significant enrichment of genes showing a selection signature and expressed in the ear in qbdCD1.1, qbdCD5.1, qbpCD2.1, qbdED1.1, qbpEL1.1, qbpEL5.1, qbdKNR1.1, and qbdKNR10.1, suggesting that these eight QTL are selected hotspots involved in shaping the maize ear. By combining the results of the QTL analysis with data from previous genome-wide association study (GWAS) involving two natural panels, we identified eight candidate selected genes related to KRN, KNR, CD, and ED. Among these, considering their expression pattern and sequence variation, Zm00001d025111, encoding a WD40/YVTN protein, was proposed as a positive regulator of KNR. This study presents a framework for understanding the genomic distribution of selected loci crucial in determining ear-related traits.
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Estudio de Asociación del Genoma Completo , Zea mays , Zea mays/genética , Genómica , Fenotipo , Sitios de Carácter CuantitativoRESUMEN
Lateral organ boundaries domain (LBD) proteins are plant-specific transcription factors. Class-I LBD genes have been widely demonstrated to play pivotal roles in organ development; however, knowledge on class-II genes remains limited. Here, we report that ZmLBD5, a class-II LBD gene, is involved in the regulation of maize (Zea mays) growth and the drought response by affecting gibberellin (GA) and abscisic acid (ABA) synthesis. ZmLBD5 is mainly involved in regulation of the TPS-KS-GA2ox gene module, which is comprised of key enzyme-encoding genes involved in GA and ABA biosynthesis. ABA insufficiency increases stomatal density and aperture in overexpression plants and causes a drought-sensitive phenotype by promoting water transpiration. Increased GA1 levels promotes seedling growth in overexpression plants. Accordingly, CRISPR/Cas9 knockout lbd5 seedlings are dwarf but drought-tolerant. Moreover, lbd5 has a higher grain yield under drought stress conditions and shows no penalty in well-watered conditions compared to the wild type. On the whole, ZmLBD5 is a negative regulator of maize drought tolerance, and it is a potentially useful target for drought resistance breeding.
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Ácido Abscísico , Resistencia a la Sequía , Ácido Abscísico/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estomas de Plantas/fisiología , Plantas Modificadas Genéticamente/metabolismo , Fitomejoramiento , Agua/metabolismo , Sequías , Regulación de la Expresión Génica de las Plantas/genética , Estrés Fisiológico/genéticaRESUMEN
RNA-binding proteins (RBPs) play significant roles in many biological life activities, many algorithms and tools are proposed to predict RBPs for researching biological mechanisms of RNA-protein binding sites. Deep learning algorithms based on traditional machine learning get better result for predicting RBPs. Recently, deep learning method fused with attention mechanism has attracted huge attention in many fields and gets competitive result. Thus, attention mechanism module may also improve model performance for predicting RNA-protein binding sites. In this study, we propose convolutional residual multi-head self-attention network (CRMSNet) that combines convolutional neural network (CNN), ResNet, and multi-head self-attention blocks to find RBPs for RNA sequence. First, CRMSNet incorporates convolutional neural networks, recurrent neural networks, and multi-head self-attention block. Second, CRMSNet can draw binding motif pictures from the convolutional layer parameters. Third, attention mechanism module combines the local and global RNA sequence information for capturing long sequence feature. CRMSNet gets competitive AUC (area under the receiver operating characteristic [ROC] curve) result in a large-scale dataset RBP-24. And CRMSNet experiment result is also compared with other state-of-the-art methods. The source code of our proposed CRMSNet method can be found in https://github.com/biomg/CRMSNet.
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Aprendizaje Profundo , Secuencia de Bases , Redes Neurales de la Computación , ARN/química , Proteínas de Unión al ARN/químicaRESUMEN
Control of magnetism has attracted interest in achieving low-power and high-speed applications such as magnetic data storage and spintronic devices. Two-dimensional magnets allow for control of magnetic properties using the electric field, electrostatic doping and strain. In two-dimensional atomically thin magnets, a non-volatile all-optical method would offer the distinct advantage of switching magnetic states without application of an external field. Here, we demonstrate such all-optical magnetization switching in the atomically thin ferromagnetic semiconductor, CrI3, triggered by circularly polarized light pulses. The magnetization switching behaviour strongly depends on the exciting photon energy and polarization, in correspondence with excitonic transitions in CrI3, indicating that the switching process is related to spin angular momentum transfer from photoexcited carriers to local magnetic moments. Such an all-optical magnetization switching should allow for further exploration of magneto-optical interactions and open up applications in high-speed and low-power spintronic devices.
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BACKGROUND: The existence of amino acid metabolic reprogramming in tumor cells is well established. However, the potential correlation between blood amino acids and the risk of colon adenocarcinoma remains largely unexplored. METHODS: We utilized Mendelian randomization (MR) analysis to examine the association between 20 amino acids in the blood and the risk of colon adenocarcinoma. Additionally, reverse MR analysis was employed to identify the presence of reverse causality. A two-step MR analysis was conducted to ascertain the potential mediating effect. Lastly, the alanine detection data from colon adenocarcinoma patients in our hospital were utilized to investigate the differences in alanine levels among healthy individuals and patients with colon cancer, as well as among patients with different stages and locations of colon cancer. Furthermore, a Kaplan-Meier curve was employed to examine the correlation between alanine and overall survival, followed by the implementation of COX univariate analysis. RESULTS: The results of our study indicate that there is an inverse correlation between alanine and the risk of colon adenocarcinoma. Additionally, we found no significant evidence to support a causal relationship between colon adenocarcinoma and alanine. Furthermore, our analysis revealed that alanine aminotransferase (ALT) and blood glucose do not act as mediators in this causal pathway. Moreover, individuals diagnosed with colon adenocarcinoma exhibited a significant decrease in alanine levels, particularly in cases of stage IV colon adenocarcinoma with distant metastasis. Additionally, elevated alanine levels were associated with improved overall survival rates among colon adenocarcinoma patients. CONCLUSIONS: The results of this study indicate that alanine exhibits protective characteristics against the onset of colon adenocarcinoma and may play a role in promoting a more favorable disease prognosis. Consequently, dietary interventions aimed at increasing alanine intake may serve as a potential strategy for the prevention and treatment of colon adenocarcinoma.
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Adenocarcinoma , Neoplasias del Colon , Humanos , Adenocarcinoma/patología , Aminoácidos , Análisis de la Aleatorización Mendeliana , Neoplasias del Colon/patología , Alanina , Estudio de Asociación del Genoma CompletoRESUMEN
Long noncoding RNAs (lncRNAs) are transcripts with lengths of more than 200 nt and limited protein-coding potential. They were found to play important roles in plant stress responses. In this study, the maize drought-tolerant inbred line AC7643 and drought-sensitive inbred line AC7729/TZSRW, as well as their recombinant inbred lines (RILs) were selected to identify drought-responsive lncRNAs in roots. Compared with non-responsive lncRNAs, drought-responsive lncRNAs had different sequence characteristics in length of genes and number of exons. The ratio of down-regulated lncRNAs induced by drought was significantly higher than that of coding genes; and lncRNAs were more widespread expressed in recombination sites in the RILs. Additionally, by integration of the modifications of DNA 5-methylcytidine (5mC), histones, and RNA N6-methyladenosine (m6A), it was found that the enrichment of histone modifications associated with transcriptional activation in the genes generated lncRNAs was lower that coding genes. The lncRNAs-mRNAs co-expression network, containing 15,340 coding genes and 953 lncRNAs, was constructed to investigate the molecular functions of lncRNAs. There are 13 modules found to be associated with survival rate under drought. We found nine SNPs located in lncRNAs among the modules associated with plant survival under drought. In conclusion, we revealed the characteristics of lncRNAs responding to drought in maize roots based on multiomics studies. These findings enrich our understanding of lncRNAs under drought and shed light on the complex regulatory networks that are orchestrated by the noncoding RNAs in response to drought stress.
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ARN Largo no Codificante , Zea mays , Zea mays/genética , ARN Largo no Codificante/genética , Sequías , Exones , Regulación de la Expresión Génica de las Plantas , Perfilación de la Expresión GénicaRESUMEN
Root architecture remodelling is critical for forage moisture in water-limited soil. DEEPER ROOTING 1 (DRO1) in Oryza, Arabidopsis, and Prunus has been reported to improve drought avoidance by promoting roots to grow downward and acquire water from deeper soil. In the present study, we found that ZmDRO1 responded more strongly to abscisic acid (ABA)/drought induction in Zea mays ssp. mexicana, an ancestral species of cultivated maize, than in B73. It was proposed that this is one of the reasons why Zea mays ssp. mexicana has a more noticeable change in the downward direction angle of the root and fewer biomass penalties under water-deficient conditions. Thus, a robust, synthetic ABA/drought-inducible promoter was used to control the expression of ZmDRO1B73 in Arabidopsis and cultivated maize for drought-resistant breeding. Interestingly, ABA-inducible ZmDRO1 promoted a larger downward root angle and improved grain yield by more than 40% under water-limited conditions. Collectively, these results revealed that different responses to ABA/drought induction of ZmDRO1 confer different drought avoidance abilities, and we demonstrated the application of ZmDRO1 via an ABA-inducible strategy to alter the root architecture of modern maize to improve drought adaptation in the field.
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Ácido Abscísico , Arabidopsis , Ácido Abscísico/metabolismo , Zea mays/metabolismo , Agua/metabolismo , Arabidopsis/metabolismo , Raíces de Plantas/metabolismo , Fitomejoramiento , Sequías , SueloRESUMEN
KEY MESSAGE: Teosinte improves maize grain yield and broadens the maize germplasm. Seventy-one quantitative trait loci associated with 24 differential traits between maize and teosinte were identified. Maize is a major cereal crop with a narrow germplasm that has limited its production and breeding progress. Teosinte, an ancestor of maize, provides valuable genetic resources for maize breeding. To identify the favorable alien alleles in teosinte and its yield potential for maize breeding, 4 backcrossed maize-teosinte recombinant inbred line (RIL) populations were cultivated under five conditions. A North Carolina mating design II experiment was conducted on inbred lines with B73 and Mo17 pedigree backgrounds to analyze their combining ability. Abundant phenotypic variation on 26 traits of four RIL populations were found, of which barren tip length, kernel height, and test weight showed positive genetic improvement potential. The hybrid FM132 (BD138/MP116) showed a superior grain yield to that of the check, with an average yield gain of 4.86%. Moreover, inbred lines BD138 and MP048 showed a higher general grain yield combining ability than those of their corresponding checks. We screened 4,964,439 high-quality single-nucleotide polymorphisms in the BD (B73/Zea diploperennis) RIL population for bin construction and used 2322 bin markers for genetic map construction and quantitative trait loci (QTL) mapping. Via inclusive composite interval mapping, 71 QTL associated with 24 differential traits were identified. Gene annotation and transcriptional expression suggested that Zm00001eb352570 and Zm00001eb352580, both annotated as ethylene-responsive transcription factors, were key candidate genes that regulate ear height and the ratio of ear to plant height. Our results indicate that teosinte could broaden the narrow maize germplasm, improve yield potential, and provide desirable alleles for maize breeding.
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Fitomejoramiento , Zea mays , Alelos , Grano Comestible/genética , Etilenos , Fenotipo , Factores de Transcripción/genética , Zea mays/genética , Zea mays/metabolismoRESUMEN
Maize (Zea mays) is an important multi-functional crop. The growth and yield of maize are severely affected by drought stress. Previous studies have shown that microRNAs (miRNAs) in maize play important roles in response to abiotic stress; however, their roles in response to drought stress in maize roots is unclear. In our study, we found 375 miRNAs in the roots of 16 inbred lines. Of the 16 lines, zma-MIR168, zma-MIR156, and zma-MIR166 were highly expressed, whereas zma-MIR399, zma-MIR2218, and zma-MIR2275 exhibited low expression levels. The expression patterns of miRNA in parental lines and their derived RILs are different. Over 50% of miRNAs exhibited a lower expression in recombinant inbred lines than in parents. The expression of 50 miRNAs was significantly altered under water stress (WS) in at least three inbred lines, and the expression of miRNAs in drought-tolerant lines changed markedly. To better understand the reasons for miRNA response to drought, the degree of histone modifications for miRNA genes was estimated. The methylation level of H3K4 and H3K9 in miRNA precursor regions changed more noticeably after WS, but no such phenomenon was seen for DNA methylation and m6A modification. After the prediction of miRNA targets using psRNATarget and psRobot, we used correlation analysis and qRT-PCR to further investigate the relationship between miRNAs and target genes. We found that 87 miRNA-target pairs were significantly negatively correlated. In addition, a weighted gene co-expression network analysis using miRNAs, as well as their predicted targets, was conducted to reveal that miR159, miR394, and miR319 may be related to maize root growth. The results demonstrated that miRNAs might play essential roles in the response to drought stress.
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MicroARNs , Zea mays , Sequías , Regulación de la Expresión Génica de las Plantas , MicroARNs/genética , MicroARNs/metabolismo , Hojas de la Planta/metabolismo , Estrés Fisiológico/genética , Zea mays/genética , Zea mays/metabolismoRESUMEN
Plant growth and development are closely related to phosphate (Pi) and auxin. However, data regarding auxin response factors (ARFs) and their response to phosphate in maize are limited. Here, we isolated ZmARF4 in maize and dissected its biological function response to Pi stress. Overexpression of ZmARF4 in Arabidopsis confers tolerance of Pi deficiency with better root morphology than wild-type. Overexpressed ZmARF4 can partially restore the absence of lateral roots in mutant arf7 arf19. The ZmARF4 overexpression promoted Pi remobilization and up-regulated AtRNS1, under Pi limitation while it down-regulated the expression of the anthocyanin biosynthesis genes AtDFR and AtANS. A continuous detection revealed higher activity of promoter in the Pi-tolerant maize P178 line than in the sensitive 9782 line under low-Pi conditions. Meanwhile, GUS activity was specifically detected in new leaves and the stele of roots in transgenic offspring. ZmARF4 was localized to the nucleus and cytoplasm of the mesophyll protoplast and interacted with ZmILL4 and ZmChc5, which mediate lateral root initiation and defense response, respectively. ZmARF4 overexpression also conferred salinity and osmotic stress tolerance in Arabidopsis. Overall, our findings suggest that ZmARF4, a pleiotropic gene, modulates multiple stress signaling pathways, and thus, could be a candidate gene for engineering plants with multiple stress adaptation.
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Fosfatos/metabolismo , Raíces de Plantas/metabolismo , Estrés Fisiológico , Factores de Transcripción/metabolismo , Zea mays/metabolismo , Antocianinas/metabolismo , Arabidopsis/genética , Organogénesis de las Plantas , Proteínas de Plantas/metabolismo , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/fisiología , Plantas Modificadas Genéticamente , Transducción de Señal , Zea mays/fisiologíaRESUMEN
Bisphenol A epoxy resin cured with a mixture of dimerized and trimerized fatty acids is the first epoxy vitrimer and has been extensively studied. However, the cure behavior and thermal and mechanical properties of this epoxy vitrimer depend on the epoxy/acid stoichiometry. To address these issues, epoxy vitrimers with three epoxy/acid stoichiometries (9:11, 1:1 and 11:9) were prepared and recycled four times. Differential scanning calorimetry (DSC) was used to study the cure behavior of the original epoxy vitrimers. The dynamic mechanical properties and mechanical performance of the original and recycled epoxy vitrimers were investigated by using dynamic mechanical analysis (DMA) and a universal testing machine. Furthermore, the reaction mechanism of epoxy vitrimer with different epoxy/acid stoichiometry was interpreted. With an increase in the epoxy/acid ratio, the reaction rate, swelling ratio, glass transition temperature and mechanical properties of the original epoxy vitrimers decreased, whereas the gel content increased. The recycling decreased the swelling ratio and elongation at break of the original epoxy vitrimers. Moreover, the elongation at break of the recycled epoxy vitrimers decreased with the epoxy/acid ratio at the same recycling time. However, the gel content, tensile strength and toughness of the original epoxy vitrimers increased after the recycling. The mechanical properties of epoxy vitrimers can be tuned with the variation in the epoxy/acid stoichiometry.
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Ácidos , Resinas Epoxi , Resinas Epoxi/química , Ácidos Grasos/química , Temperatura , Resistencia a la TracciónRESUMEN
The application of crumb rubber from end-of-life tires and waste cooking oil (WCO) in road pavements is of significant importance from an economic and environmental viewpoint. However, the incorporation of crumb rubber greatly shortens the allowable construction time of epoxy asphalt binders due to the high viscosity of the epoxy asphalt rubber (EAR) binder and poor compatibility between crumb rubber and asphalt binder. To lower the viscosity of asphalt rubber, extend the allowable construction time and improve the compatibility of EAR binder, waste cooking oil (WCO) was introduced. The effect of WCO on the viscosity-time behavior, thermal stability, dynamic modulus, glass transitions, crosslink density, damping ability, compatibility, mechanical properties and phase separation of WCO-modified EAR binders was investigated by using the Brookfield viscometer, thermogravimetric analysis, dynamic mechanical analysis, universal testing machine and laser confocal microscopy. The test results demonstrated that the incorporation of WCO declined the viscosity and extended the allowable construction time of the unmodified EAR binder. The inclusion of WCO improved the compatibility between asphalt and crumb rubber and the damping ability and elongation at the break of the unmodified EAR binder. The presence of WCO had a marginal effect on the thermal stability of the unmodified EAR binder. Confocal microscopy observation revealed that asphalt rubber particles aggregated in the epoxy phase of the unmodified EAR binder. With the inclusion of WCO, co-continuous asphalt rubber particles became more spherical.
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Culinaria , Hidrocarburos , Viscosidad , Resinas EpoxiRESUMEN
The frontal eye field (FEF) is a key part of the oculomotor system, with dominant responses to the direction of single saccades. However, whether and how FEF contributes to sequential saccades remain largely unknown. By training rhesus monkeys to perform saccade sequences, we found sequence-related activities in FEF neurons, whose selectivity to saccade direction undergoes dynamic changes during sequential vs. single saccades. These sequence-related activities are context-dependent, exhibiting different firing activities during memory- vs. visually guided sequences. When the monkey was performing the sequential saccade task, the thresholds of microstimulation to evoke saccades in FEF were increased and the percentage of the successfully induced saccades was significantly reduced compared with the fixation condition. Pharmacological inactivation of FEF impaired the monkey's performance of previously learned sequential saccades, with different effects on the same actions depending on its position within the sequence. These results reveal the context-dependent, sequence-specific dynamic encoding of saccades in FEF, and underscore the crucial role of FEF in the planning and execution of sequential saccades. KEY POINTS: FEF neurons respond differently during sequential vs. single saccades Sequence-related FEF activity is context-dependent The microstimulation threshold in FEF was increased during the sequential task but the evoked saccade did not alter the sequence structure FEF inactivation severely impaired the performance of sequential saccades.
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Lóbulo Frontal , Movimientos Sacádicos , Animales , Macaca mulatta , NeuronasRESUMEN
The new physics of magic-angle twisted bilayer graphene (TBG) motivated extensive studies of flat bands hosted by moiré superlattices in van der Waals structures, inspiring the investigations into their photonic counterparts with potential applications including Bose-Einstein condensation. However, correlation between photonic flat bands and bilayer photonic moiré systems remains unexplored, impeding further development of moiré photonics. In this work, we formulate a coupled-mode theory for low-angle twisted bilayer honeycomb photonic crystals as a close analogy of TBG, discovering magic-angle photonic flat bands with a non-Anderson-type localization. Moreover, the interlayer separation constitutes a convenient degree of freedom in tuning photonic moiré bands without high pressure. A phase diagram is constructed to correlate the twist angle and separation dependencies to the photonic magic angles. Our findings reveal a salient correspondence between fermionic and bosonic moiré systems and pave the avenue toward novel applications through advanced photonic band or state engineering.
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DNA methylation is important for plant growth, development, and stress response. To understand DNA methylation dynamics in maize roots under water stress (WS), we reanalyzed DNA methylation sequencing data to profile DNA methylation and the gene expression landscape of two inbred lines with different drought sensitivities, as well as two of their derived recombination inbred lines (RILs). Combined with genotyping-by-sequencing, we found that the inheritance pattern of DNA methylation between RILs and parental lines was sequence-dependent. Increased DNA methylation levels were observed under WS and the methylome of drought-tolerant inbred lines were much more stable than that of the drought-sensitive inbred lines. Distinctive differentially methylated genes were found among diverse genetic backgrounds, suggesting that inbred lines with different drought sensitivities may have responded to stress in varying ways. Gene body DNA methylation showed a negative correlation with gene expression but a positive correlation with exon splicing events. Furthermore, a positive correlation of a varying extent was observed between small interfering RNA (siRNA) and DNA methylation, which at different genic regions. The response of siRNAs under WS was consistent with the differential DNA methylation. Taken together, our data can be useful in deciphering the roles of DNA methylation in plant drought-tolerance variations and in emphasizing its function in alternative splicing.
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Empalme Alternativo , Metilación de ADN , Estrés Fisiológico , Zea mays/genética , Sequías , Regulación de la Expresión Génica de las Plantas , Zea mays/metabolismoRESUMEN
PURPOSE: To evaluate the degree of gastric, enteric, colonic, and rectal filling in multidetector computed tomography (MDCT) whole gastroenterography. METHODS: In this prospective study involving 124 patients, 78 and 46 patients underwent MDCT whole gastroenterography using positive and neutral oral contrast agents, respectively. The degree of filling of the stomach, small and large bowel, was qualitatively analyzed by experienced radiologists using a 3-point scoring system. RESULTS: The majority of patients received a score of ≥2 for small intestine filling using both positive and neutral contrast agents (90.5% and 78.2%, respectively), and <9% of the patients had a score of 0. The highest score for the degree of filling in the small intestine was observed in the ileum, followed by the duodenum and jejunum. There was a significant difference in the degree of filling achieved with positive and neutral contrast agents in the duodenum (P = .013) and jejunum (P = .047). More than 74% of cases had an optimal filling of the stomach, whereas >80% of the cases had an optimal filling of the colorectal segments. Only ≤5.1% had a score of 0 for the analyzed segments of the colorectum. Positive and neutral contrast agents were associated with similar degree of filling in the stomach and colon segments without a significant difference in the extent of contrast agent filling (P > .05). CONCLUSIONS: Multidetector computed tomography whole gastroenterography was found to be a simple, safe, noninvasive, painless, and effective modality for the diagnosis of stomach and bowel complications in clinical settings.
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Neoplasias del Colon/diagnóstico por imagen , Medios de Contraste , Tracto Gastrointestinal/diagnóstico por imagen , Tomografía Computarizada Multidetector/métodos , Administración Oral , Adulto , Anciano , Anciano de 80 o más Años , Colon/diagnóstico por imagen , Pólipos del Colon/diagnóstico por imagen , Medios de Contraste/administración & dosificación , Femenino , Humanos , Intestino Delgado/diagnóstico por imagen , Masculino , Manitol/administración & dosificación , Persona de Mediana Edad , Estudios Prospectivos , Dosis de Radiación , Recto/diagnóstico por imagen , Estómago/diagnóstico por imagen , Ácidos Triyodobenzoicos/administración & dosificaciónRESUMEN
The motor and nonmotor symptoms of PD involve several brain regions. However, whether α-syn pathology originating from the SNc can directly lead to the pathological changes in distant cerebral regions and induce PD-related symptoms remains unclear. Here, AAV9-synapsin-mCherry-human SNCA (A53T) was injected into the unilateral SNc of mice. Motor function and olfactory sensitivity were evaluated. Our results showed that AAV9-synapsin-mCherry-human SNCA was continuously expressed in SNc. The animals showed mild motor and olfactory dysfunction at 7 months after viral injection. The pathology in SNc was characterized by the loss of dopaminergic neurons accompanied by ER stress. In the striatum, hα-syn expression was high, CaMKß-2 and NR2B expression decreased, and active synapses reduced. In the olfactory bulb, hα-syn expression was high, and aging cells in the mitral layer increased. The results suggested that hα-syn was transported in the striatum and OB along the nerve fibers that originated from the SNc and induced pathological changes in the distant cerebral regions, which contributed to the motor and nonmotor symptoms of PD.