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1.
Brain ; 147(1): 39-55, 2024 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-37691438

RESUMEN

Brain perivascular macrophages are specialized populations of macrophages that reside in the space around cerebral vessels, such as penetrating arteries and venules. With the help of cutting-edge technologies, such as cell fate mapping and single-cell multi-omics, their multifaceted, pivotal roles in phagocytosis, antigen presentation, vascular integrity maintenance and metabolic regulation have more recently been further revealed under physiological conditions. Accumulating evidence also implies that perivascular macrophages are involved in the pathogenesis of neurodegenerative disease, cerebrovascular dysfunction, autoimmune disease, traumatic brain injury and epilepsy. They can act in either protective or detrimental ways depending on the disease course and stage. However, the underlying mechanisms of perivascular macrophages remain largely unknown. Therefore, we highlight potential future directions in research on perivascular macrophages, including the utilization of genetic mice and novel therapeutic strategies that target these unique immune cells for neuroprotective purposes. In conclusion, this review provides a comprehensive update on the current knowledge of brain perivascular macrophages, shedding light on their pivotal roles in central nervous system health and disease.


Asunto(s)
Enfermedades Neurodegenerativas , Ratones , Animales , Enfermedades Neurodegenerativas/patología , Encéfalo/patología , Macrófagos/metabolismo , Sistema Nervioso Central , Fagocitosis
2.
J Opt Soc Am A Opt Image Sci Vis ; 41(4): 694-699, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38568669

RESUMEN

The degree of paraxiality (DOP) of a radially polarized twisted multi-Gaussian Schell-model (RPT MGSM) beam is discussed, and the influence of the source parameters on its DOP is studied. It is shown that the parameters of the beam source, including the boundary characteristic, the beam waist width, the coherence width of the source correlation, and the twist factor, have a significant impact on the DOP of the RPT MGSM beam. To explain the behaviors of the DOP, the far-field divergence angle of this beam is also discussed.

3.
J Environ Manage ; 351: 119736, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38064982

RESUMEN

In megacities, vehicle emissions face urgent challenges related to air pollution and CO2 control. To achieve the refinement of vehicle control policies for the co-control of air pollutants and CO2, this study established a vehicle emission inventory with high spatial and temporal resolution based on the hourly traffic flow in Shanghai and analyzed the spatial and temporal distribution characteristics of the real-time vehicle emissions. Meanwhile, a policy evaluation framework was constructed by combining pollutant emission predictions with quantitative co-control effect assessments. The results indicated that spatio-temporal variations in different air pollutants and CO2 could mainly be attributed to primary contributing vehicle types. The pollutants (CO2, CO and VOCs) primarily contributed by private cars exhibited a bimodal pattern in 24-h time series and their spatial distribution was concentrated in the urban city center. The spatial distribution of NOx and PM primarily contributed by heavy trucks was still obvious on non-urban center areas. Furthermore, the results of synergistic effect analysis revealed that the alternative energy replacement scenario demonstrated the most significant potential for the co-control. Based on temporal-spatial and co-benefit analysis, the precise control policy of vehicle emissions can be established through time-, region-, and model-control. This study provides references and research methods for the formulation of the vehicle refinement control policies in worldwide megacities.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Contaminantes Atmosféricos/análisis , Emisiones de Vehículos/análisis , Dióxido de Carbono , China , Monitoreo del Ambiente/métodos , Contaminación del Aire/prevención & control , Contaminación del Aire/análisis , Vehículos a Motor
4.
J Integr Plant Biol ; 66(4): 731-748, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38482956

RESUMEN

Soil salinity has a major impact on rice seed germination, severely limiting rice production. Herein, a rice germination defective mutant under salt stress (gdss) was identified by using chemical mutagenesis. The GDSS gene was detected via MutMap and shown to encode potassium transporter OsHAK9. Phenotypic analysis of complementation and mutant lines demonstrated that OsHAK9 was an essential regulator responsible for seed germination under salt stress. OsHAK9 is highly expressed in germinating seed embryos. Ion contents and non-invasive micro-test technology results showed that OsHAK9 restricted K+ efflux in salt-exposed germinating seeds for the balance of K+/Na+. Disruption of OsHAK9 significantly reduced gibberellin 4 (GA4) levels, and the germination defective phenotype of oshak9a was partly rescued by exogenous GA3 treatment under salt stress. RNA sequencing (RNA-seq) and real-time quantitative polymerase chain reaction analysis demonstrated that the disruption of OsHAK9 improved the GA-deactivated gene OsGA2ox7 expression in germinating seeds under salt stress, and the expression of OsGA2ox7 was significantly inhibited by salt stress. Null mutants of OsGA2ox7 created using clustered, regularly interspaced, short palindromic repeat (CRISPR)/CRISPR-associated nuclease 9 approach displayed a dramatically increased seed germination ability under salt stress. Overall, our results highlight that OsHAK9 regulates seed germination performance under salt stress involving preventing GA degradation by mediating OsGA2ox7, which provides a novel clue about the relationship between GA and OsHAKs in rice.


Asunto(s)
Giberelinas , Oryza , Giberelinas/farmacología , Giberelinas/metabolismo , Germinación/fisiología , Potasio/metabolismo , Oryza/metabolismo , Semillas/metabolismo , Estrés Salino , Proteínas de Transporte de Membrana/metabolismo , Regulación de la Expresión Génica de las Plantas
5.
Plant Physiol ; 190(4): 2417-2429, 2022 11 28.
Artículo en Inglés | MEDLINE | ID: mdl-36053193

RESUMEN

Histone modifications are essential for chromatin activity and play an important role in many biological processes. Trimethylation of histone H3K27 (H3K27me3) is a repressive modification established by Polycomb Repressive Complex 2 (PRC2). Although the presence of the histone H3 serine 28 phosphorylation (H3S28ph) modification at adjacent amino acid residues has both positive and negative effects on Polycomb silencing in mammals, little is known about the effect of H3S28ph on H3K27me3-mediated gene silencing in plants. In this study, we show that mutating H3S28A in Arabidopsis (Arabidopsis thaliana) causes a dominant-negative effect that leads to an early-flowering phenotype by promoting the expression of flowering-promoting genes independently of abnormal cell division. While H3S28ph levels decreased due to the H3S28A mutation, H3K27me3 levels at the same loci did not increase. Moreover, we observed decreased H3K27me3 levels at some known PRC2 target genes in H3.3S28A transgenic lines, rather than the expected enhanced H3K27me3-mediated silencing. In line with the reduced H3K27me3 levels, the expression of the PRC2 catalytic subunits CURLY LEAF and SWINGER decreased. Taken together, these data demonstrate that H3.3S28 is required for PRC2-dependent H3K27me3-mediated silencing in Arabidopsis, suggesting that H3S28 has a noncanonical function in H3K27me3-mediated gene silencing.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Animales , Arabidopsis/genética , Arabidopsis/metabolismo , Histonas/genética , Histonas/metabolismo , Serina/genética , Serina/metabolismo , Alanina/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Complejo Represivo Polycomb 2/genética , Complejo Represivo Polycomb 2/metabolismo , Silenciador del Gen , Mutación/genética , Regulación de la Expresión Génica de las Plantas , Mamíferos/metabolismo , Factores de Transcripción/metabolismo
6.
Theor Appl Genet ; 136(3): 58, 2023 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-36912929

RESUMEN

KEY MESSAGE: Two causal OsTTL and OsSAPK1 genes of the key locus qNL3.1 significantly associated with seed germination under salt stress were identified via a genome-wide association study, which could improve rice seed germination under salt stress. Rice is a salt-sensitive crop, and its seed germination determines subsequent seedling establishment and yields. In this study, 168 accessions were investigated for the genetic control of seed germination under salt stress based on the germination rate (GR), germination index (GI), time at which 50% germination was achieved (T50) and mean level (ML). Extensive natural variation in seed germination was observed among accessions under salt stress. Correlation analysis showed significantly positive correlations among GR, GI and ML and a negative correlation with T50 during seed germination under salt stress. Forty-nine loci significantly associated with seed germination under salt stress were identified, and seven of these were identified in both years. By comparison, 16 loci were colocated with the previous QTLs, and the remaining 33 loci might be novel. qNL3.1, colocated with qLTG-3, was simultaneously identified with the four indices in two years and might be a key locus for seed germination under salt stress. Analysis of candidate genes showed that two genes, the similar to transthyretin-like protein OsTTL and the serine/threonine protein kinase OsSAPK1, were the causal genes of qNL3.1. Germination tests indicated that both Osttl and Ossapk1 mutants significantly reduced seed germination under salt stress compared to the wild type. Haplotype analysis showed that Hap.1 of OsTTL and Hap.1 of OsSAPK1 genes were excellent alleles, and their combination resulted in high seed germination under salt stress. Eight accessions with elite performance of seed germination under salt stress were identified, which could improve rice seed germination under salt stress.


Asunto(s)
Germinación , Oryza , Germinación/genética , Oryza/genética , Estudio de Asociación del Genoma Completo/métodos , Semillas/genética , Estrés Salino/genética
7.
Environ Sci Technol ; 57(44): 16779-16787, 2023 11 07.
Artículo en Inglés | MEDLINE | ID: mdl-37897419

RESUMEN

As one of the emerging pollutants, microplastics (MPs) can be taken up by aquatic organisms through ingestion. However, little is known about the uptake pattern in organisms over time and the associated mechanisms of retention patterns. The present study aims to elucidate these patterns in fish, their relationship with light/dark conditions, and examine the uptake kinetic process of small-sized plastic pollutants, especially during the long-neglected dark period. Zebrafish were sampled every 2 h during the light and dark periods after exposure to an environmentally relevant concentration (100 items/L) of MPs. The results demonstrated that MP residues in zebrafish decreased during the dark period rather than increased over time. The MP retention rhythm and the swimming behavior of exposed zebrafish displayed a statistically significant light/dark variation. Moreover, a very strong and statistically significant positive correlation was found between the swimming speed of zebrafish and the number of MP residues in the gastrointestinal tracts of zebrafish. These results clearly demonstrate that fibrous MP residues in the fish have a discernible diel pattern. This work improves the understanding of the dynamic residual process of MPs in organisms and calls for further in-depth circadian toxicokinetic studies to better suit particle pollutants.


Asunto(s)
Contaminantes Ambientales , Contaminantes Químicos del Agua , Animales , Microplásticos , Pez Cebra , Plásticos , Organismos Acuáticos , Contaminantes Químicos del Agua/análisis
8.
Ecotoxicol Environ Saf ; 264: 115464, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37708690

RESUMEN

Emissions from the iron and steel industry are a major source of air pollution. To investigate the composition characteristics, estimate the secondary transformation potential, and assess the ecological risk and human health risks of air pollutants from iron and steel industry, field measurements of volatile organic compounds (VOCs) and trace metals (TMs) were conducted simultaneously from 2020 to 2022 in the Yangtze River Delta (YRD) region, China. The average mixing concentration of VOCs (Σ64VOCs) was 58.2 ppbv. Alkanes, alkenes and aromatics were the major components. Benzene and ethylene were the most abundant VOC species. In the O3 season, the calculated OH loss rates (LOH) and ozone formation potential (OFP) were 10.87 S-1 and 181.74 ppbv, respectively, which increased 39.54% and 21.51% compared to the non-O3 season. Furthermore, the O3-VOCs-NOx sensitivity indicated that O3 formation was under the VOCs-limited regime. The average concentration of total 10 trace metals (Σ10TMs) was 226.8 ng m-3, Zn, Pb and Mn were the top abundant TM species. The results also found that Se was extremely contaminated; Pb and Zn was heavily to extremely contaminated; Cu, As and Ni were moderately to heavily contaminated. For lifetime cancer risk, the cumulative carcinogenic risks were 1.84E-5 for children, 6.14E-5 for adults and 1.83E-5 for workers. The carcinogenic risks of individual chemicals cannot be ignored, especially for Cr, Ni, benzene and 1,3-butadiene. The hazard index values for workers and residents were 0.53 and 2.23, respectively, suggesting a high non-carcinogenic risks to the exposed population. These findings deepen the understanding of the pollutant character of the iron and steel industry, and provide theoretical support for policy development on O3 pollution treatment and human health in the YRD region, China. For the study area, we recommend utilizing high-quality raw coal, reducing the volatile hydrocarbon content in the sinter feed, and installing absorption device for highly reactive VOC components at the exhaust outlet.


Asunto(s)
Contaminantes Ambientales , Oligoelementos , Compuestos Orgánicos Volátiles , Adulto , Niño , Humanos , Hierro , Benceno , Plomo , China , Carcinogénesis , Carcinógenos
9.
Ecotoxicol Environ Saf ; 263: 115274, 2023 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-37499389

RESUMEN

Polyethylene microplastics have been detected in farmland soil, irrigation water, and soil organisms in agroecosystems, while plastic mulching is suggested as a crucial source of microplastic pollution in the agroecosystem. Plastic mulch can be broken down from plastic mulch debris to microplastics through environmental aging and degradation process in farmlands, and the colonization of polyethylene-degrading microorganisms on polyethylene microplastics can eventually enzymatically depolymerize the polyethylene molecular chains with CO2 release through the tricarboxylic acid cycle. The selective colonization of microplastics by soil microorganisms can cause changes in soil microbial community composition, and it can consequently elicit changes in enzyme activities and nutrient element content in the soil. The biological uptake of polyethylene microplastics and the associated disturbance of energy investment are the main mechanisms impacting soil-dwelling animal development and behavior. As polyethylene microplastics are highly hydrophobic, their presence among soil particles can contribute to soil water repellency and influence soil water availability. Polyethylene microplastics have been shown to cause impacts on crop plant growth, as manifested by the effects of polyethylene microplastics on soil properties and soil biota in the agroecosystems. This review reveals the degradation process, biological impacts, and associated mechanisms of polyethylene microplastics in agroecosystems and could be a critical reference for their risk assessment and management.


Asunto(s)
Microplásticos , Contaminantes del Suelo , Animales , Microplásticos/toxicidad , Plásticos/toxicidad , Agricultura , Polietileno/toxicidad , Contaminantes del Suelo/toxicidad , Contaminantes del Suelo/análisis , Suelo/química
10.
J Environ Manage ; 344: 118373, 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37329586

RESUMEN

China is presently confronted with the intricate challenge of simultaneously mitigating air pollution and decelerating the pace of climate change. An integrated perspective to investigate the synergetic control of CO2 and air pollutant emissions is in an urgent need. Using data for 284 Chinese cities from 2009 to 2017, we introduced an indicator called coupling and coordination degree of CO2 and air pollutant emissions control (CCD) and found an upward and spatial agglomeration trend of CCD distribution during the research period. Then, this study posed a specific focus on the impact of China's Air Pollution Prevention and Control Action Plan (APPCAP). The DID model revealed that implementation of the APPCAP resulted in a 4.0% increase in CCD for cities with special emission limits, attributed to industrial structural adjustments and the promotion of technology innovation. Furthermore, we also identified positive spillover effects of the APPCAP on neighboring control group cities situated within 350 km of the treatment group cities, providing an explanation for the spatial agglomeration trend observed in CCD distribution. These findings hold significant implications for the synergetic control in China and underscored the potential benefits of industrial structural adjustments and technology innovation in mitigating environmental pollution.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Contaminantes Atmosféricos/análisis , Ciudades , Dióxido de Carbono , Contaminación del Aire/prevención & control , Contaminación del Aire/análisis , China , Material Particulado/análisis
11.
J Environ Sci (China) ; 125: 603-615, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36375942

RESUMEN

Wuhan Tianhe International Airport (WUH) was suspended to contain the spread of COVID-19, while Shanghai Hongqiao International Airport (SHA) saw a tremendous flight reduction. Closure of a major international airport is extremely rare and thus represents a unique opportunity to straightforwardly observe the impact of airport emissions on local air quality. In this study, a series of statistical tools were applied to analyze the variations in air pollutant levels in the vicinity of WUH and SHA. The results of bivariate polar plots show that airport SHA and WUH are a major source of nitrogen oxides. NOx, NO2 and NO diminished by 55.8%, 44.1%, 76.9%, and 40.4%, 33.3% and 59.4% during the COVID-19 lockdown compared to those in the same period of 2018 and 2019, under a reduction in aircraft activities by 58.6% and 61.4%. The concentration of NO2, SO2 and PM2.5 decreased by 77.3%, 8.2%, 29.5%, right after the closure of airport WUH on 23 January 2020. The average concentrations of NO, NO2 and NOx scatter plots at downwind of SHA after the lockdown were 78.0%, 47.9%, 57.4% and 62.3%, 34.8%, 41.8% lower than those during the same period in 2018 and 2019. However, a significant increase in O3 levels by 50.0% and 25.9% at WUH and SHA was observed, respectively. These results evidently show decreased nitrogen oxides concentrations in the airport vicinity due to reduced aircraft activities, while amplified O3 pollution due to a lower titration by NO under strong reduction in NOx emissions.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , COVID-19 , Humanos , Aeropuertos , Emisiones de Vehículos/análisis , Dióxido de Nitrógeno/análisis , COVID-19/epidemiología , China , Control de Enfermedades Transmisibles , Contaminación del Aire/análisis , Contaminantes Atmosféricos/análisis , Aeronaves , Óxidos de Nitrógeno/análisis , Monitoreo del Ambiente/métodos , Material Particulado/análisis
12.
Stroke ; 53(12): 3751-3762, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36305312

RESUMEN

BACKGROUND: Emerging evidence highlighted vascular injury in aggravating radiation-induced brain injury (RIBI), a common complication of radiotherapy. This study aimed to delineate the pathological feature of cerebral small vessel and investigate the functional roles of Notch signaling in RIBI. METHODS: Brain tissue and functional MRI from RIBI patients were collected and analyzed for radiation-induced vasculopathy. A RIBI mouse model was induced by a single dose of 30-Gy cranial irradiation. Vascular morphology, pulsatility, and reactivity to pharmacological interventions, such as nimodipine and 20-hydroxyeicosa-6(Z),15(Z)-dienoic acid, were monitored by 2-photon imaging in mice at 6 weeks postirradiation. Western blot, real-time quantitative PCR, immunofluorescence staining, and behavioral tests were performed. The effect of N-[N-(3, 5-difluorophenacetyl)-l-alanyl]-s-phenylglycinet-butyl ester, a Notch inhibitor, was used to investigate the vascular pathogenesis of RIBI mouse model. RESULTS: Morphologically, radiation resulted in vascular malformation featured by focal contractile rings together with general stenosis. Functionally, radiation also led to hypoperfusion, attenuated vascular pulsatility, and decreased dilation to nimodipine and 20-hydroxyeicosa-6(Z),15(Z)-dienoic acid. Mechanically, Notch activation and increased expression of α-SMA protein were found in both surgical specimens of RIBI patients and the irradiated mice. Importantly, Notch inhibition by N-[N-(3, 5-difluorophenacetyl)-l-alanyl]-s-phenylglycinet-butyl ester significantly alleviated cerebral hypoperfusion, vasculopathy, and cognitive deficits in the RIBI mouse model. CONCLUSIONS: Radiation-induced cerebral vasculopathy showed bead-like shape and increased contractile state. Inhibition of Notch signaling by N-[N-(3, 5-difluorophenacetyl)-l-alanyl]-s-phenylglycinet-butyl ester effectively attenuated vasculopathy and relieved cognitive impairment, suggesting Notch signaling as a therapeutic target for the treatment of RIBI.


Asunto(s)
Lesiones Encefálicas , Trastornos Cerebrovasculares , Traumatismos por Radiación , Animales , Ratones , Nimodipina , Miocitos del Músculo Liso/patología , Transducción de Señal , Trastornos Cerebrovasculares/complicaciones , Lesiones Encefálicas/patología , Ésteres/metabolismo , Ésteres/farmacología , Receptores Notch/metabolismo
13.
Plant Biotechnol J ; 20(7): 1346-1362, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35315188

RESUMEN

The cultivation of rice varieties with high seed vigour is vital for the direct seeding of rice, and the molecular basis of regulation of seed vigour remains elusive. Here, we cloned a new gene OsHIPL1, which encodes hedgehog-interacting protein-like 1 protein as a causal gene of the major QTL qSV3 for rice seed vigour. OsHIPL1 was mainly localized in the plasma membrane and nucleus. RNA sequencing (RNA-seq) revealed that the ABA-related genes were involved in the OsHIPL1 regulation of seed vigour in rice. The higher levels of endogenous ABA were measured in germinating seeds of OsHIPL1 mutants and NIL-qsv3 line compared to IR26 plants, with two up-regulated ABA biosynthesis genes (OsZEP and OsNCED4) and one down-regulated ABA catabolism gene OsABA8ox3. The expression of abscisic acid-insensitive 3 (OsABI3), OsABI4 and OsABI5 was significantly up-regulated in germinating seeds of OsHIPL1 mutants and NIL-qsv3 line compared to IR26 plants. These results indicate that the regulation of seed vigour of OsHIPL1 may be through modulating endogenous ABA levels and altering OsABIs expression during seed germination in rice. Meanwhile, we found that OsHIPL1 interacted with the aquaporin OsPIP1;1, then affected water uptake to promote rice seed germination. Based on analysis of single-nucleotide polymorphism data of rice accessions, we identified a Hap1 haplotype of OsHIPL1 that was positively correlated with seed germination. Our findings showed novel insights into the molecular mechanism of OsHIPL1 on seed vigour.


Asunto(s)
Oryza , Ácido Abscísico/metabolismo , Regulación de la Expresión Génica de las Plantas/genética , Germinación/genética , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Oryza/metabolismo , Semillas/metabolismo
14.
New Phytol ; 235(6): 2252-2269, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35638341

RESUMEN

Dimethylation of histone H3 lysine 9 (H3K9me2), a crucial modification for heterochromatin formation and transcriptional silencing, is essential for proper meiotic prophase progression in mammals. We analyzed meiotic defects and generated genome-wide profiles of H3K9me2 and transcriptomes for the mutants of H3K9 demethylases. Moreover, we also identified proteins interacting with H3K9 demethylases. H3K9me2 is usually found at transposable elements and repetitive sequences but is absent from the bodies of protein-coding genes. In this study, we show that the Arabidopsis thaliana H3K9 demethylases IBM1 and JMJ27 cooperatively regulate crossover formation and chromosome segregation. They protect thousands of protein-coding genes from ectopic H3K9me2, including genes essential for meiotic prophase progression. In addition to removing H3K9me2, IBM1 and JMJ27 interact with the Precocious Dissociation of Sisters 5 (PDS5) cohesin complex cofactors. The pds5 mutant shared similar transcriptional alterations with ibm1 jmj27, including meiosis-essential genes, yet without affecting H3K9me2 levels. Hence, PDS5s, together with IBM1 and JMJ27, regulate male meiosis and gene expression independently of H3K9 demethylation. These findings uncover a novel role of H3K9me2 removal in meiosis and a new function of H3K9 demethylases and cohesin cofactors in meiotic transcriptional regulation.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Animales , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Histonas/metabolismo , Histona Demetilasas con Dominio de Jumonji/genética , Histona Demetilasas con Dominio de Jumonji/metabolismo , Mamíferos , Meiosis
15.
J Exp Bot ; 73(5): 1402-1414, 2022 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-34698830

RESUMEN

Polyploidy is a widespread phenomenon in flowering plant species. Polyploid plants frequently exhibit considerable transcriptomic alterations after whole-genome duplication (WGD). It is known that the transcriptomic response to tetraploidization is ecotype-dependent in Arabidopsis; however, the biological significance and the underlying mechanisms are unknown. In this study, we found that 4x Col-0 presents a delayed flowering time whereas 4x Ler does not. The expression of FLOWERING LOCUS C (FLC), the major repressor of flowering, was significantly increased in 4x Col-0 but only a subtle change was present in 4x Ler. Moreover, the level of a repressive epigenetic mark, trimethylation of histone H3 at lysine 27 (H3K27me3), was significantly decreased in 4x Col-0 but not in 4x Ler, potentially leading to the differences in FLC transcription levels and flowering times. Hundreds of other genes in addition to FLC showed H3K27me3 alterations in 4x Col-0 and 4x Ler. LIKE HETEROCHROMATIN PROTEIN 1 (LHP1) and transcription factors required for H3K27me3 deposition presented transcriptional changes between the two ecotypes, potentially accounting for the different H3K27me3 alterations. We also found that the natural 4x Arabidopsis ecotype Wa-1 presented an early flowering time, which was associated with low expression of FLC. Taken together, our results demonstrate a role of H3K27me3 alterations in response to genome duplication in Arabidopsis autopolyploids, and that variation in flowering time potentially functions in autopolyploid speciation.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Ecotipo , Flores/genética , Flores/metabolismo , Regulación de la Expresión Génica de las Plantas , Proteínas de Dominio MADS/genética , Proteínas de Dominio MADS/metabolismo , Poliploidía
16.
J Exp Bot ; 73(11): 3446-3461, 2022 06 02.
Artículo en Inglés | MEDLINE | ID: mdl-35191960

RESUMEN

Seed germination plays a pivotal role in the plant life cycle, and its precise regulatory mechanisms are not clear. In this study, 19 quantitative trait loci (QTLs) associated with rice seed germination were identified through genome-wide association studies (GWAS) of the following traits in 2016 and 2017: germination rate (GR) at 3, 5, and 7 days after imbibition (DAI) and germination index (GI). Two major stable QTLs, qSG4 and qSG11.1, were found to be associated with GR and GI over 2 continuous years. Furthermore, OsPK5, encoding a pyruvate kinase, was shown to be a crucial regulator of seed germination in rice, and might be a causal gene of the key QTL qSG11.1, on chromosome 11. Natural variation in OsPK5 function altered the activity of pyruvate kinase. The disruption of OsPK5 function resulted in slow germination and seedling growth during seed germination, blocked glycolytic metabolism, caused glucose accumulation, decreased energy levels, and affected the GA/ABA balance. Taken together, our results provide novel insights into the roles of OsPK5 in seed germination, and facilitate its application in rice breeding to improve seed vigour.


Asunto(s)
Oryza , Ácido Abscísico/metabolismo , Regulación de la Expresión Génica de las Plantas , Estudio de Asociación del Genoma Completo , Germinación/genética , Oryza/genética , Oryza/metabolismo , Fitomejoramiento , Piruvato Quinasa/genética , Piruvato Quinasa/metabolismo , Semillas
17.
Plant Cell ; 31(5): 956-973, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30894459

RESUMEN

Lariats are formed by excised introns, when the 5' splice site joins with the branchpoint (BP) during splicing. Although lariat RNAs are usually degraded by RNA debranching enzyme 1, recent findings in animals detected many lariat RNAs under physiological conditions. By contrast, the features of BPs and to what extent lariat RNAs accumulate naturally are largely unexplored in plants. Here, we analyzed 948 RNA sequencing data sets to document plant BPs and lariat RNAs on a genome-wide scale. In total, we identified 13,872, 5199, 29,582, and 13,478 BPs in Arabidopsis (Arabidopsis thaliana), tomato (Solanum lycopersicum), rice (Oryza sativa), and maize (Zea mays), respectively. Features of plant BPs are highly similar to those in yeast and human, in that BPs are adenine-preferred and flanked by uracil-enriched sequences. Intriguingly, ∼20% of introns harbor multiple BPs, and BP usage is tissue-specific. Furthermore, 10,580 lariat RNAs accumulate in wild-type Arabidopsis plants, and most of these lariat RNAs originate from longer or retroelement-depleted introns. Moreover, the expression of these lariat RNAs is accompanied by the incidence of back-splicing of parent exons. Collectively, our results provide a comprehensive map of intron BPs and lariat RNAs in four plant species and uncover a link between lariat turnover and splicing.


Asunto(s)
Arabidopsis/genética , Oryza/genética , ARN de Planta/genética , Solanum lycopersicum/genética , Zea mays/genética , Intrones/genética , Precursores del ARN/genética , Empalme del ARN/genética
18.
Plant Cell ; 31(5): 1077-1093, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30923230

RESUMEN

Brassinosteroids (BRs) are steroid hormones that play essential roles in plant growth and development. We previously cloned qGL3, a major quantitative trait locus regulating grain length in rice (Oryza sativa). The O. sativa japonica var N411 has extra-large grains compared with the O. sativa indica var 9311, and the recessive qgl3 allele from N411 contributes positively to grain length. qGL3 encodes a putative protein phosphatase with Kelch-like repeat domains, an ortholog of Arabidopsis (Arabidopsis thaliana) brassinosteroid-insensitive1 SUPPRESSOR1 (BSU1). BSU1 positively regulates BR signaling, while overexpression of qGL3 induced BR loss-of-function phenotypes. Both qGL3N411 and qGL39311 physically interact with the rice glycogen synthase kinase 3 (GSK3)/SHAGGY-like kinase 3 (OsGSK3), an ortholog of Arabidopsis BR INSENSITIVE2 (BIN2). qGL39311 dephosphorylates OsGSK3, but qGL3N411 lacks this activity. Knocking out OsGSK3 enhances BR signaling and induces nuclear localization of O. sativa BRASSINAZOLE RESISTANT1 (OsBZR1). Unlike the dephosphorylation of BIN2 (which leads to protein degradation) in Arabidopsis, qGL3 dephosphorylates and stabilizes OsGSK3 in rice. These results demonstrate that qGL3 suppresses BR signaling by regulating the phosphorylation and stability of OsGSK3, which modulates OsBZR1 phosphorylation and subcellular distribution. Our study clarifies the role of qGL3 in the regulation of grain length and provides insight into BR signaling, including the differences between rice and Arabidopsis.


Asunto(s)
Brasinoesteroides/metabolismo , Oryza/genética , Proteínas de Plantas/metabolismo , Transducción de Señal , Arabidopsis/enzimología , Arabidopsis/genética , Arabidopsis/fisiología , Glucógeno Sintasa Quinasa 3/genética , Glucógeno Sintasa Quinasa 3/metabolismo , Mutación con Pérdida de Función , Oryza/enzimología , Oryza/fisiología , Fosforilación , Proteínas de Plantas/genética
19.
J Opt Soc Am A Opt Image Sci Vis ; 39(6): 1111-1116, 2022 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-36215542

RESUMEN

The definition of the degree of paraxiality (DOP) for a stochastic electromagnetic field is applied to a twist stochastic electromagnetic field. As an illustrative example, DOP for a wide class of model stochastic fields, i.e., twist electromagnetic Gaussian Schell-model (TEGSM) fields, is discussed. The dependence of the DOP of the light source on its properties is also studied in detail. The numerical results show that the DOP of a TEGSM beam is determined by the rms widths of auto-correlation functions and the twist factor as well as by the degree of polarization. To explain the behavior of DOP, the far-field divergence angle of this beam source is also discussed.

20.
BMC Public Health ; 22(1): 767, 2022 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-35428227

RESUMEN

BACKGROUND: Previous research suggested an association between maternal exposure to ambient air pollutants and the risk of congenital heart disease (CHD). However, the effect of individual prenatal exposure to indoor air pollutants on CHD occurrence was not reported. METHODS: We performed a hospital-based case-control study to investigate the association between personal air pollution exposure during pregnancy and the risk of CHD in offspring. A total of 44 cases and 75 controls were included from two hospitals in East China. We investigated maternal and residential environmental characteristics using a questionnaire and obtained personal indoor air samples to assess particulate matter (PM) and volatile organic compounds (VOCs) from 22-30 gestational weeks. Formaldehyde, benzene, toluene, xylene, total volatile organic compounds (TVOCs), PM2.5, and PM10 were assessed. Logistic regression was performed to assess associations and interactions between individual indoor air pollutants and CHD after adjusting for confounders. The potential residential environmental factors affecting the risks of indoor air pollutants on CHD were also assessed. RESULTS: Median TVOC (0.400 vs. 0.005 mg/m3, P < 0.001) exposure levels in cases were significantly higher than controls. A logistic regression model adjusted for confounders revealed that exposure to high levels of indoor TVOCs (AOR 7.09, 95% CI 2.10-23.88) during pregnancy was associated with risks for CHD and the occurrence of some major CHD subtype in offspring. These risk effects were enhanced in pregnant women living in a newly renovated house but were mitigated by household use of smoke ventilators when cooking. We observed a positive interaction of maternal exposure to TVOCs and PM2.5 and the risk for CHD. CONCLUSIONS: Maternal exposure to indoor VOCs and PMs may increase the risk of giving birth to foetuses with CHD.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire Interior , Contaminación del Aire , Cardiopatías Congénitas , Compuestos Orgánicos Volátiles , Contaminantes Atmosféricos/efectos adversos , Contaminantes Atmosféricos/análisis , Contaminación del Aire Interior/efectos adversos , Contaminación del Aire Interior/análisis , Estudios de Casos y Controles , China/epidemiología , Femenino , Cardiopatías Congénitas/epidemiología , Cardiopatías Congénitas/etiología , Humanos , Exposición Materna/efectos adversos , Material Particulado/efectos adversos , Material Particulado/análisis , Embarazo , Compuestos Orgánicos Volátiles/efectos adversos
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