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1.
Nanotechnology ; 35(18)2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38358678

RESUMEN

Graphene is broadly applied as sensitive sensing material results from its superb features. Concurrently, as a derivative of graphene with 0D structure, graphene quantum dots (GQDs) offer more possibilities as a supportive sensing material due to its adjustable size and functional group modification. In this work, GQDs are introduced to single-layer graphene (SLG) based humidity sensor to enhance the sensing performance. Specifically, consistent resistance response to relative humidity (RH) is extended from the range of 10%-60% to 10%-90% by contrary to original SLG based sensor. Parallelly, effect of the amount of GQDs is investigated by means of multiple GQDs deposition. As the resultant higher binding efficiency between water molecules and the functional groups of GQDs, improved response rate is observed. For the case of 4-time deposition of GQDs, the response rate (ΔR/R) reaches ∼130% in RH range of 10%-90%. Besides, the response time and recovery time are ∼0.7 s and ∼1.1 s, respectively. The fluctuation of the resistance change of the sensor under constant humidity is less than 5% over a month which demonstrates long-term reliability.

2.
Nanotechnology ; 35(16)2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38215490

RESUMEN

In this paper, a preparation method of superhydrophobic composites of oxidized multi-walled carbon nanotubes modified by stearic acid (SA) is proposed. Hydroxylated multi-walled carbon nanotubes (HMWCNTs) were obtained by oxidizing multi-walled carbon nanotubes with potassium dichromate to give them hydroxyl groups on the surface. Subsequently, the carboxyl group in the SA molecule was esterified with the hydroxyl group on the HMWCNTs. SA molecules were grafted onto the surface of multi-walled carbon nanotubes. SA modified oxidized multi-walled carbon nanotubes (SMWCNT) superhydrophobic composites were obtained. The results show that the water contact angle (WCA) of superhydrophobic composites can reach up to 174°. At the same time, the modified nanocomposites have good anti-icing and corrosion resistance. After low temperature delayed freezing test, the freezing extension time of the nanocomposite film is 30 times that of the smooth surface. Under strong acid and alkali conditions, the superhydrophobic nanocomposites still maintain good superhydrophobicity. The nanocomposites may have potential applications in the preparation of large-scale superhydrophobic coatings.

3.
Plant Cell Environ ; 45(2): 412-426, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34855989

RESUMEN

Long noncoding RNAs (lncRNAs) have been considered to be important regulators of gene expression in a range of biological processes in plants. A large number of lncRNAs have been identified in plants. However, most of their biological functions still remain to be determined. Here, we identified a total of 3004 lncRNAs in cassava under normal or cold-treated conditions from Iso-seq data. We further characterized a cold-responsive intergenic lncRNA 1 (CRIR1) as a novel positive regulator of the plant response to cold stress. CRIR1 can be significantly induced by cold treatment. Ectopic expression of CRIR1 in cassava enhanced the cold tolerance of transgenic plants. Transcriptome analysis demonstrated that CRIR1 regulated a range of cold stress-related genes in a CBF-independent pathway. We further found that CRIR1 RNA can interact with cassava cold shock protein 5 (MeCSP5), which acts as an RNA chaperone, indicating that CRIR1 may recruit MeCSP5 to improve the translation efficiency of messenger RNA. In summary, our study extends the repertoire of lncRNAs in plants as well as their role in cold stress responses. Moreover, it reveals a mechanism by which CRIR1 affected cold stress response by modulating the expression of stress-responsive genes and increasing their translational yield.


Asunto(s)
Respuesta al Choque por Frío/genética , Manihot/genética , ARN Largo no Codificante/genética , ARN de Planta/genética , Manihot/metabolismo , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/metabolismo , ARN Largo no Codificante/metabolismo , ARN de Planta/metabolismo
4.
Theor Appl Genet ; 135(3): 817-832, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34837123

RESUMEN

KEY MESSAGE: Analysis of drought-related genes in cassava shows the involvement of MeSPL9 in drought stress tolerance and overexpression of a dominant-negative form of this gene demonstrates its negative roles in drought stress resistance. Drought stress severely impairs crop yield and is considered a primary threat to food security worldwide. Although the SQUAMOSA promoter binding protein-like 9 (SPL9) gene participates extensively in numerous developmental processes and in plant response to abiotic stimuli, its role and regulatory pathway in cassava (Manihot esculenta) response to the drought condition remain elusive. In the current study, we show that cassava SPL9 (MeSPL9) plays negative roles in drought stress resistance. MeSPL9 expression was strongly repressed by drought treatment. Overexpression of a dominant-negative form of miR156-resistant MeSPL9, rMeSPL9-SRDX, in which a 12-amino acid repressor sequence was fused to rMeSPL9 at the C terminus, conferred drought tolerance without penalizing overall growth. rMeSPL9-SRDX-overexpressing lines not only exhibited increased osmoprotectant metabolites including proline and anthocyanin, but also accumulated more endogenous jasmonic acid (JA) and soluble sugars. Transcriptomic and real-time PCR analysis suggested that differentially expressed genes were involved in sugar or JA biosynthesis, signaling, and metabolism in transgenic cassava under drought conditions. Exogenous application of JA further confirmed that JA conferred improved drought resistance and promoted stomatal closure in cassava leaves. Taken together, our findings suggest that MeSPL9 affects drought resistance by modulating protectant metabolite levels and JA signaling, which have substantial implications for engineering drought tolerant crops.


Asunto(s)
Sequías , Manihot , Ciclopentanos , Regulación de la Expresión Génica de las Plantas , Manihot/genética , Manihot/metabolismo , Oxilipinas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estrés Fisiológico/genética
5.
J Am Acad Dermatol ; 87(6): 1328-1335, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-33031838

RESUMEN

BACKGROUND: Observational studies have shown promising therapeutic effects of long-pulsed neodymium-doped yttrium-aluminum-garnet (LP-Nd:YAG) laser on warts. OBJECTIVE: To evaluate whether LP-Nd:YAG laser was superior to cryotherapy for cutaneous warts. METHODS: In this study, 150 adult patients with warts were randomized equally to receive laser or cryotherapy every 3 to 4 weeks, for a maximum of 4 sessions. The primary outcomes were the cure rates at 16 weeks and 6 months; secondary outcomes included time to clearance of warts and treatment-related adverse effects. RESULTS: There was no difference in the cure rate for laser versus cryotherapy at 16 weeks (54.1% vs 46.7%, respectively) and 6 months (59.5% vs 57.3%, respectively). However, time to clearance of warts, up to 16 weeks and 6 months, tended to be shorter for laser versus cryotherapy (P = .04 and .08, respectively). Post hoc analyses showed a significantly higher cure rate for laser versus cryotherapy in 3 subgroups of human papillomavirus 2/27/57-induced recalcitrant warts but not in their counterpart subgroups. Laser had more mild adverse effects. LIMITATIONS: Single center. CONCLUSIONS: The overall therapeutic effects of LP-Nd:YAG laser were similar to cryotherapy, but laser may be more effective to relatively recalcitrant warts and may be associated with shorter time to clearance of warts.


Asunto(s)
Láseres de Estado Sólido , Verrugas , Adulto , Humanos , Láseres de Estado Sólido/uso terapéutico , Neodimio , Resultado del Tratamiento , Verrugas/terapia , Crioterapia/efectos adversos
6.
Anal Chem ; 93(5): 2996-3001, 2021 02 09.
Artículo en Inglés | MEDLINE | ID: mdl-33508943

RESUMEN

Lateral flow biosensor (LFB) is one of the most successful and applied commercial detection methods for food safety, drug abuse, and disease. Here, we integrated the ultrasound enrichment as sample preparation with LFB to achieve the ultra-trace protein detection in blood. When the ultrasound field is applied, the interaction between the acoustic field and gold nanoparticles can gather specifically modified gold nanoparticles toward pressure nodes in seconds and enrich target proteins. Such an approach can detect protein with a linear range of 1-20 ng mL-1 and detection limit of 0.58 ng mL-1 in blood within 20 min, which enormously reduces false positive readings caused by interference in real blood samples with complex components. Such a microchip that integrated acoustic enrichment with LFB shows great potential in detecting ultra-trace biomarkers for clinical diagnosis.


Asunto(s)
Técnicas Biosensibles , Nanopartículas del Metal , Oro , Técnicas de Amplificación de Ácido Nucleico
7.
J Exp Bot ; 71(1): 422-434, 2020 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-31713628

RESUMEN

Alternative splicing is an essential post-transcriptional regulatory mechanism that can impact mRNA stability and protein diversity of eukaryotic genomes. Although numerous forms of stress-responsive alternative splicing have been identified in model plants, a large-scale study of alternative splicing dynamics under abiotic stress conditions in cassava has not been conducted. Here, we report the parallel employment of isoform-Seq, ssRNA-Seq, and Degradome-Seq to investigate the diversity, abundance, and fate of alternatively spliced isoforms in response to cold and drought stress. We identified 38 164 alternative splicing events, among which 3292 and 1025 events were significantly regulated by cold and drought stress, respectively. Intron retention was the most abundant subtype of alternative splicing. Global analysis of splicing regulators revealed that the number of their alternatively spliced isoforms and the corresponding abundance were specifically modulated by cold stress. We found that 58.5% of cold-regulated alternative splicing events introduced a premature termination codon into the transcripts, and 77.6% of differential alternative splicing events were detected by Degradome-Seq. Our data reveal that cold intensely affects both quantitative and qualitative aspects of gene expression via alternative splicing pathways, and advances our understanding of the high complexity and specificity of gene regulation in response to abiotic stresses. Alternative splicing is responsible for reprogramming of the transcriptome and the sensitivity of cassava plants to cold.


Asunto(s)
Empalme Alternativo/fisiología , Respuesta al Choque por Frío/genética , Sequías , Manihot/fisiología , Transcriptoma , Manihot/genética
8.
Br J Nutr ; 124(12): 1285-1292, 2020 12 28.
Artículo en Inglés | MEDLINE | ID: mdl-32594922

RESUMEN

Excessive gestational weight gain (GWG) increases the risk of maternal anaemia during pregnancy, but whether it is associated with offspring anaemia has not been investigated. We aimed to prospectively investigate the association of GWG rate in the second/third trimester with infant Hb concentration and anaemia risk. The present study comprised 13 765 infants born during 2006-2009 to mothers who participated in a trial on prenatal micronutrient supplementation. The GWG was calculated by subtracting the maternal weight at enrolment from that at end-pregnancy. The GWG rate was calculated as dividing the GWG by number of weeks between the two measurements and classified into quintiles within each category of maternal BMI. Infant Hb concentrations were measured at 6 and 12 months of age, and anaemia was defined as an Hb concentration <110 g/l. Of the 13 765 infants, 949 (6·9 %) were anaemic at 6 months and 728 (5·3 %) at 12 months. The GWG rate was inversely and linearly associated with the infant Hb concentrations at both 6 and 12 months (P < 0·001 for linearity). Compared with the middle quintile of GWG rate, the highest quintile was associated with an increased risk of anaemia at 6 months (adjusted OR 1·30, 95 % CI 1·07, 1·59) and 12 months (adjusted OR 1·74, 95 % CI 1·40, 2·17). The associations were consistently mediated by maternal anaemia during pregnancy (P < 0·001). In conclusion, excessive GWG rate appears to be associated with an increased risk of infant anaemia, partly independent of maternal anaemia during pregnancy that mediates the association.


Asunto(s)
Anemia/fisiopatología , Ganancia de Peso Gestacional , Complicaciones del Embarazo/fisiopatología , Efectos Tardíos de la Exposición Prenatal/etiología , Adulto , Anemia/sangre , Anemia/etiología , China , Suplementos Dietéticos , Femenino , Hemoglobinas/análisis , Humanos , Lactante , Micronutrientes/administración & dosificación , Embarazo , Complicaciones del Embarazo/sangre , Complicaciones del Embarazo/etiología , Trimestres del Embarazo/sangre , Atención Prenatal/métodos , Estudios Prospectivos , Ensayos Clínicos Controlados Aleatorios como Asunto
9.
PLoS Genet ; 13(5): e1006827, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28562599

RESUMEN

Meiotic recombination is required for proper homologous chromosome segregation in plants and other eukaryotes. The eukaryotic RAD51 gene family has seven ancient paralogs with important roles in mitotic and meiotic recombination. Mutations in mammalian RAD51 homologs RAD51C and XRCC3 lead to embryonic lethality. In the model plant Arabidopsis thaliana, RAD51C and XRCC3 homologs are not essential for vegetative development but are each required for somatic and meiotic recombination, but the mechanism of RAD51C and XRCC3 in meiotic recombination is unclear. The non-lethal Arabidopsis rad51c and xrcc3 null mutants provide an opportunity to study their meiotic functions. Here, we show that AtRAD51C and AtXRCC3 are components of the RAD51-dependent meiotic recombination pathway and required for normal AtRAD51 localization on meiotic chromosomes. In addition, AtRAD51C interacts with both AtRAD51 and AtXRCC3 in vitro and in vivo, suggesting that these proteins form a complex (es). Comparison of AtRAD51 foci in meiocytes from atrad51, atrad51c, and atxrcc3 single, double and triple heterozygous mutants further supports an interaction between AtRAD51C and AtXRCC3 that enhances AtRAD51 localization. Moreover, atrad51c-/+ atxrcc3-/+ double and atrad51-/+ atrad51c-/+ atxrcc3-/+ triple heterozygous mutants have defects in meiotic recombination, suggesting the role of the AtRAD51C-AtXRCC3 complex in meiotic recombination is in part AtRAD51-dependent. Together, our results support a model in which direct interactions between the RAD51C-XRCC3 complex and RAD51 facilitate RAD51 localization on meiotic chromosomes and RAD51-dependent meiotic recombination. Finally, we hypothesize that maintenance of RAD51 function facilitated by the RAD51C-XRCC3 complex could be highly conserved in eukaryotes.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Recombinación Homóloga , Meiosis , Recombinasa Rad51/metabolismo , Arabidopsis/citología , Arabidopsis/metabolismo , Unión Proteica
10.
Int J Mol Sci ; 20(17)2019 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-31450745

RESUMEN

Avocado (Persea americana Mill.) is an economically important crop because of its high nutritional value. However, the absence of a sequenced avocado reference genome has hindered investigations of secondary metabolism. For next-generation high-throughput transcriptome sequencing, we obtained 365,615,152 and 348,623,402 clean reads as well as 109.13 and 104.10 Gb of sequencing data for avocado mesocarp and seed, respectively, during five developmental stages. High-quality reads were assembled into 100,837 unigenes with an average length of 847.40 bp (N50 = 1725 bp). Additionally, 16,903 differentially expressed genes (DEGs) were detected, 17 of which were related to carotenoid biosynthesis. The expression levels of most of these 17 DEGs were higher in the mesocarp than in the seed during five developmental stages. In this study, the avocado mesocarp and seed transcriptome were also sequenced using single-molecule long-read sequencing to acquired 25.79 and 17.67 Gb clean data, respectively. We identified 233,014 and 238,219 consensus isoforms in avocado mesocarp and seed, respectively. Furthermore, 104 and 59 isoforms were found to correspond to the putative 11 carotenoid biosynthetic-related genes in the avocado mesocarp and seed, respectively. The isoform numbers of 10 out of the putative 11 genes involved in the carotenoid biosynthetic pathway were higher in the mesocarp than those in the seed. Besides, alpha- and beta-carotene contents in the avocado mesocarp and seed during five developmental stages were also measured, and they were higher in the mesocarp than in the seed, which validated the results of transcriptome profiling. Gene expression changes and the associated variations in gene dosage could influence carotenoid biosynthesis. These results will help to further elucidate carotenoid biosynthesis in avocado.


Asunto(s)
Carotenoides/metabolismo , Regulación de la Expresión Génica de las Plantas , Persea/genética , Persea/metabolismo , Semillas/genética , Semillas/metabolismo , Transcriptoma , Vías Biosintéticas , Biología Computacional/métodos , Dosificación de Gen , Perfilación de la Expresión Génica , Ontología de Genes , Metaboloma , Metabolómica/métodos , Anotación de Secuencia Molecular , Desarrollo de la Planta/genética
11.
BMC Genomics ; 19(1): 454, 2018 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-29898655

RESUMEN

BACKGROUND: Bananas (Musa spp.) are the most important fruit crops worldwide due to their high nutrition value. Fusarium wilt of banana, caused by fungal pathogen Fusarium oxysporum f. sp. cubense tropical race 4 (Foc 4), is considered as the most destructive disease in the world and results in extensive damage leading to productivity loss. The widespread use of plant resistance inducers (PRIs), such as benzothiadiazole (BTH), is a novel strategy to stimulate defense responses in banana plants to protect against pathogens infection. The recent focus on the crop defense against fungal infections has led to a renewed interest on understanding the molecular mechanisms of specific PRIs-mediated resistance. This transcriptome study aimed to identify genes that are associated with BTH-induced resistance. Patterns of gene expression in the leaves and roots of BTH-sprayed banana plants were studied using RNA-Seq. RESULTS: In this study, 18 RNA-Seq libraries from BTH-sprayed and untreated leaves and roots of the Cavendish plants, the most widely grown banana cultivar, were used for studying the transcriptional basis of BTH-related resistance. Comparative analyses have revealed that 6689 and 3624 differentially expressed genes were identified in leaves and roots, respectively, as compared to the control. Approximately 80% of these genes were differentially expressed in a tissue-specific manner. Further analysis showed that signaling perception and transduction, transcription factors, disease resistant proteins, plant hormones and cell wall organization-related genes were stimulated by BTH treatment, especially in roots. Interestingly, the ethylene and auxin biosynthesis and response genes were found to be up-regulated in leaves and roots, respectively, suggesting a choice among BTH-responsive phytohormone regulation. CONCLUSIONS: Our data suggests a role for BTH in enhancing banana plant defense responses to Foc 4 infection, and demonstrates that BTH selectively affect biological processes associated with plant defenses. The genes identified in the study could be further studied and exploited to develop Foc 4-resistant banana varieties.


Asunto(s)
Fusarium/fisiología , Regulación de la Expresión Génica de las Plantas , Musa/genética , Enfermedades de las Plantas/microbiología , Tiadiazoles/farmacología , Transcriptoma/efectos de los fármacos , Pared Celular/metabolismo , Resistencia a la Enfermedad , Perfilación de la Expresión Génica , Genes cdc , Genoma de Planta , Musa/efectos de los fármacos , Musa/metabolismo , Musa/microbiología , Enfermedades de las Plantas/genética , Reguladores del Crecimiento de las Plantas/biosíntesis , Reguladores del Crecimiento de las Plantas/fisiología , Proteínas de Plantas/biosíntesis , Proteínas de Plantas/genética , Especies Reactivas de Oxígeno/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Metabolismo Secundario/genética , Transducción de Señal , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
12.
J Fluoresc ; 28(4): 905-911, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29936595

RESUMEN

A colorimetric and fluorescent indicator based on cinnamamide group-containing rhodamine derivative was synthesized for the detection of Hg2+. The rhodamine B and cinnamamide were connected via ethylenediamine as a bridging molecule through a condensation reaction to obtain a colorimetric and fluorescent indicator for the detection of Hg2+ in H2O-EtOH (4:1, v/v). The indicator was excellent in the selectivity of Hg2+ and was almost unaffected by other common ions such as Na+, K+, Mg2+, Fe3+, Cu2+, Zn2+, Cr3+. The Hg2+-containing aqueous solution turned from colorless to red within 7 min after the addition of the indicator, and had an absorption peak at 564 nm in UV-vis, which implies a significant colorimetric phenomenon. Their characteristic peaks varied with the Hg2+ content, and they reached a linear relationship at low concentrations. The binding stoichiometry proved to be 1:1. The lowest detection limit was 4.1 × 10-7 mol/L, ranging from acidic to neutral.

13.
J Fluoresc ; 28(3): 809-814, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29808393

RESUMEN

In this paper, a new kind of colorimetric chemsensor aiming at detecting Cr3+ has been synthesized, and it is based on the "Off-On" effect of a rhodamine derivative. Comparing with other metal irons (Na+, K+, Ni2+, Hg2+, Fe3+, Mn2+, Co2+, Cd2+, Cu2+, Pb2+, Zn2+, Mg2+, Ba2+, Ag+, Fe2+, Ce3+), the chemsensor has a quick and accurate response to Cr3+ in H2O-EtOH solution (4/1, v/v). There is an obvious change in color, from colorless to bright pink when Cr3+ is detected. According to the fitting curve based on Benesi-Hildebrand equation and working curve of absorption strength in UV-vis spectrum, the binding pattern of Cr3+ and the rhodamine derivative follows a 1:1 stoichiometry. The chemsensor shows great potential in monitoring Cr3+ in the aqueous medium with high efficiency, which is supposed to complete the recognition in the minimum as 5.2 × 10-7 mol/L within 5 min.

14.
Proc Natl Acad Sci U S A ; 112(40): 12534-9, 2015 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-26392549

RESUMEN

Meiosis halves diploid genomes to haploid and is essential for sexual reproduction in eukaryotes. Meiotic recombination ensures physical association of homologs and their subsequent accurate segregation and results in the redistribution of genetic variations among progeny. Most organisms have two classes of cross-overs (COs): interference-sensitive (type I) and -insensitive (type II) COs. DNA synthesis is essential for meiotic recombination, but whether DNA synthesis has a role in differentiating meiotic CO pathways is unknown. Here, we show that Arabidopsis POL2A, the homolog of the yeast DNA polymerase-ε (a leading-strand DNA polymerase), is required for plant fertility and meiosis. Mutations in POL2A cause reduced fertility and meiotic defects, including abnormal chromosome association, improper chromosome segregation, and fragmentation. Observation of prophase I cell distribution suggests that pol2a mutants likely delay progression of meiotic recombination. In addition, the residual COs in pol2a have reduced CO interference, and the double mutant of pol2a with mus81, which affects type II COs, displayed more severe defects than either single mutant, indicating that POL2A functions in the type I pathway. We hypothesize that sufficient leading-strand DNA elongation promotes formation of some type I COs. Given that meiotic recombination and DNA synthesis are conserved in divergent eukaryotes, this study and our previous study suggest a novel role for DNA synthesis in the differentiation of meiotic recombination pathways.


Asunto(s)
Proteínas de Arabidopsis/genética , Intercambio Genético/genética , ADN Polimerasa II/genética , ADN de Plantas/genética , Meiosis/genética , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Segregación Cromosómica/genética , Cromosomas de las Plantas/genética , ADN Polimerasa II/metabolismo , ADN de Plantas/metabolismo , Fertilidad/genética , Hibridación Fluorescente in Situ , Microscopía Fluorescente , Modelos Genéticos , Mutación , Plantas Modificadas Genéticamente , Subunidades de Proteína/genética , Subunidades de Proteína/metabolismo , Recombinación Genética/genética
15.
PLoS Genet ; 8(11): e1003039, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23144629

RESUMEN

During meiotic recombination, induced double-strand breaks (DSBs) are processed into crossovers (COs) and non-COs (NCO); the former are required for proper chromosome segregation and fertility. DNA synthesis is essential in current models of meiotic recombination pathways and includes only leading strand DNA synthesis, but few genes crucial for DNA synthesis have been tested genetically for their functions in meiosis. Furthermore, lagging strand synthesis has been assumed to be unnecessary. Here we show that the Arabidopsis thaliana DNA replication factor C1 (RFC1) important for lagging strand synthesis is necessary for fertility, meiotic bivalent formation, and homolog segregation. Loss of meiotic RFC1 function caused abnormal meiotic chromosome association and other cytological defects; genetic analyses with other meiotic mutations indicate that RFC1 acts in the MSH4-dependent interference-sensitive pathway for CO formation. In a rfc1 mutant, residual pollen viability is MUS81-dependent and COs exhibit essentially no interference, indicating that these COs form via the MUS81-dependent interference-insensitive pathway. We hypothesize that lagging strand DNA synthesis is important for the formation of double Holliday junctions, but not alternative recombination intermediates. That RFC1 is found in divergent eukaryotes suggests a previously unrecognized and highly conserved role for DNA synthesis in discriminating between recombination pathways.


Asunto(s)
Arabidopsis/genética , Segregación Cromosómica/genética , Intercambio Genético/genética , Proteína de Replicación C/genética , Cromosomas de las Plantas/genética , Roturas del ADN de Doble Cadena , ADN Helicasas/genética , ADN Helicasas/metabolismo , Replicación del ADN/genética , Recombinación Homóloga/genética , Meiosis/genética , Mutación
16.
BMC Plant Biol ; 14: 169, 2014 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-24939556

RESUMEN

BACKGROUND: Soybean is one of the most important crops, providing large amounts of dietary proteins and edible oil, and is also an excellent model for studying evolution of duplicated genes. However, relative to the model plants Arabidopsis and rice, the present knowledge about soybean transcriptome is quite limited. RESULTS: In this study, we employed RNA-seq to investigate transcriptomes of 11 soybean tissues, for genome-wide discovery of truly expressed genes, and novel and alternative transcripts, as well as analyses of conservation and divergence of duplicated genes and their functional implications. We detected a total of 54,132 high-confidence expressed genes, and identified 6,718 novel transcriptional regions with a mean length of 372 bp. We also provided strong evidence for alternative splicing (AS) events for ~15.9% of the genes with two or more exons. Among them, 1,834 genes exhibited stage-dependent AS, and 202 genes had tissue-biased exon-skipping events. We further defined the conservation and divergence in expression patterns between duplicated gene pairs from recent whole genome duplications (WGDs); differentially expressed genes, tissue preferentially expressed genes, transcription factors and specific gene family members were identified for shoot apical meristem and flower development. CONCLUSIONS: Our results significantly improved soybean gene annotation, and also provide valuable resources for functional genomics and studies of the evolution of duplicated genes from WGDs in soybean.


Asunto(s)
Empalme Alternativo/genética , Evolución Molecular , Glycine max/genética , Meristema/genética , Análisis de Secuencia de ARN/métodos , Secuencia Conservada/genética , Duplicación de Gen , Perfilación de la Expresión Génica , Regulación del Desarrollo de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Genes Duplicados , Genes de Plantas , Meristema/metabolismo , Análisis de Secuencia por Matrices de Oligonucleótidos , Especificidad de Órganos/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , Factores de Transcripción/metabolismo , Transcriptoma/genética
17.
New Phytol ; 201(1): 292-304, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24102485

RESUMEN

The eukaryotic RAD51 gene family has seven ancient paralogs conserved between plants and animals. Among these, RAD51, DMC1, RAD51C and XRCC3 are important for homologous recombination and/or DNA repair, whereas single mutants in RAD51B, RAD51D or XRCC2 show normal meiosis, and the lineages they represent diverged from each other evolutionarily later than the other four paralogs, suggesting possible functional redundancy. The function of Arabidopsis RAD51B, RAD51D and XRCC2 genes in mitotic DNA repair and meiosis was analyzed using molecular genetic, cytological and transcriptomic approaches. The relevant double and triple mutants displayed normal vegetative and reproductive growth. However, the triple mutant showed greater sensitivity than single or double mutants to DNA damage by bleomycin. RNA-Seq transcriptome analysis supported the idea that the triple mutant showed DNA damage similar to that caused by bleomycin. On bleomycin treatment, many genes were altered in the wild-type but not in the triple mutant, suggesting that the RAD51 paralogs have roles in the regulation of gene transcription, providing an explanation for the hypersensitive phenotype of the triple mutant to bleomycin. Our results provide strong evidence that Arabidopsis XRCC2, RAD51B and RAD51D have complex functions in somatic DNA repair and gene regulation, arguing for further studies of these ancient genes that have been maintained in both plants and animals during their long evolutionary history.


Asunto(s)
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Daño del ADN , Reparación del ADN , Proteínas de Unión al ADN/genética , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Recombinasa Rad51/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas de Unión al ADN/metabolismo , Meiosis , Mitosis , Mutación , Fenotipo , Recombinasa Rad51/metabolismo
18.
ACS Omega ; 9(4): 4447-4454, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38313553

RESUMEN

The operation of aerospace equipment is often affected by icing and frosting. In order to reduce the loss caused by icing in the industrial field, it is an effective method to prepare superhydrophobic coatings by modifying nanoparticles with low surface energy materials. In order to explore a method of preparing a superhydrophobic surface that can be popularized, a two-step spraying method was employed to create a superhydrophobic coating. The surface was characterized by Fourier transform infrared spectroscopy (FTIR) and field emission scanning electron microscopy (SEM). The optimal preparation process was obtained by analyzing the surface contact angle data. The results showed that stearic acid was grafted onto the surface of TiO2 by esterification reaction. The existence of long methyl and methylene hydrophobic groups in the tail of the stearic acid molecule made the modified TiO2 hydrophobic. It is verified that water molecules have strong adsorption on the surface of unmodified TiO2. Stearic acid molecules can reduce the interfacial energy in the system.

19.
Nanomaterials (Basel) ; 14(10)2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38786844

RESUMEN

The exploration of catalysts for the oxygen evolution reaction (OER) with high activity and acceptable price is essential for water splitting to hydrogen generation. High-entropy materials (HEMs) have aroused increasing interest in the field of electrocatalysis due to their unusual physicochemical properties. In this work, we reported a novel FeCoNiMoZn-OH high entropy hydroxide (HEH)/nickel foam (NF) synthesized by a facile pulsed electrochemical deposition method at room temperature. The FeCoNiMoZn-OH HEH displays a 3D porous nanosheet morphology and polycrystalline structure, which exhibits extraordinary OER activity in alkaline media, including much lower overpotential (248 mV at 10 mA cm-2) and Tafel slope (30 mV dec-1). Furthermore, FeCoNiMoZn-OH HEH demonstrates excellent OER catalytic stability. The enhanced catalytic performance of the FeCoNiMoZn-OH HEH primarily contributed to the porous morphology and the positive synergistic effect between Mo and Zn. This work provides a novel insight into the design of HEMs in catalytic application.

20.
Nat Genet ; 56(1): 136-142, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38082204

RESUMEN

Most fresh bananas belong to the Cavendish and Gros Michel subgroups. Here, we report chromosome-scale genome assemblies of Cavendish (1.48 Gb) and Gros Michel (1.33 Gb), defining three subgenomes, Ban, Dh and Ze, with Musa acuminata ssp. banksii, malaccensis and zebrina as their major ancestral contributors, respectively. The insertion of repeat sequences in the Fusarium oxysporum f. sp. cubense (Foc) tropical race 4 RGA2 (resistance gene analog 2) promoter was identified in most diploid and triploid bananas. We found that the receptor-like protein (RLP) locus, including Foc race 1-resistant genes, is absent in the Gros Michel Ze subgenome. We identified two NAP (NAC-like, activated by apetala3/pistillata) transcription factor homologs specifically and highly expressed in fruit that directly bind to the promoters of many fruit ripening genes and may be key regulators of fruit ripening. Our genome data should facilitate the breeding and super-domestication of bananas.


Asunto(s)
Fusarium , Musa , Musa/genética , Fusarium/genética , Triploidía , Fitomejoramiento , Factores de Transcripción/genética , Enfermedades de las Plantas/genética
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