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1.
Environ Res ; 244: 117935, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38103781

RESUMO

Nanofiltration (NF) membranes, extensively used in advanced wastewater treatment, have broad application prospects for the removal of emerging trace organic micropollutants (MPs). The treatment performance is affected by several factors, such as the properties of NF membranes, characteristics of target MPs, and operating conditions of the NF system concerning MP rejection. However, quantitative studies on different contributors in this context are limited. To fill the knowledge gap, this study aims to assess critical impact factors controlling MP rejection and develop a feasible model for MP removal prediction. The mini-review firstly summarized membrane pore size, membrane zeta potential, and the normalized molecular size (λ = rs/rp), showeing better individual relationships with MP rejection by NF membranes. The Lindeman-Merenda-Gold model was used to quantitatively assess the relative importance of all summarized impact factors. The results showed that membrane pore size and operating pressure were the high impact factors with the highest relative contribution rates to MP rejection of 32.11% and 25.57%, respectively. Moderate impact factors included membrane zeta potential, solution pH, and molecular radius with relative contribution rates of 10.15%, 8.17%, and 7.83%, respectively. The remaining low impact factors, including MP charge, molecular weight, logKow, pKa and crossflow rate, comprised all the remaining contribution rates of 16.19% through the model calculation. Furthermore, based on the results and data availabilities from references, the machine learning-based random forest regression model was trained with a relatively low root mean squared error and mean absolute error of 12.22% and 6.92%, respectively. The developed model was then successfully applied to predict MPs' rejections by NF membranes. These findings provide valuable insights that can be applied in the future to optimize NF membrane designs, operation, and prediction in terms of removing micropollutants.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Poluentes Químicos da Água/química , Purificação da Água/métodos
2.
J Environ Manage ; 354: 120263, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38387360

RESUMO

Biogenic carbon emissions, including carbon dioxide (CO2) and methane (CH4), have emerged as a major concern during organic pollutant degradation within constructed wetlands (CWs). Since these organic compounds primarily originate from the photosynthetic fixation of atmospheric CO2, it potentially introduces uncertainty when assessing the greenhouse effect of biogenic carbon emissions in CWs based on direct field observations. To objectively assessing this effect, this study proposed a new strategy by quantifying CO2-equivalent (CO2-eq) changes as carbon passes through CWs and tested it in various types of CWs based on 64 literature records. The findings reveal that CWs can contribute to CO2-eq additions, yet are only responsible for 15.6% derived from direct field observations. The type of CWs plays a crucial role in these CO2-eq additions, with vertical flow CWs causing the lowest levels (6.8%), followed by surface flow CWs (14.2%). In contrast, horizontal flow CWs are associated with the strongest CO2-eq addition (25.7%). The findings provide new insights for the objective assessment of the greenhouse effect of biogenic carbon emissions in CWs, which will be beneficial for future life cycle assessment.


Assuntos
Poluentes Ambientais , Áreas Alagadas , Efeito Estufa , Dióxido de Carbono/análise , Metano , Óxido Nitroso/análise
3.
New Phytol ; 239(5): 1790-1803, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37430391

RESUMO

Meiotic crossovers ensure accurate chromosome segregation and increase genetic diversity. RAD51C and RAD51D play an early role in facilitating RAD51 during homologous recombination. However, their later function in meiosis is largely unknown in plants. Here, through targeted disruption of RAD51C and RAD51D, we generated three new mutants and revealed their later meiotic role in crossover maturation. The rad51c-3 and rad51d-4 mutants showed a mixture of bivalents and univalents and no chromosomal entanglements, whereas rad51d-5 exhibited an intermediate phenotype with reduced chromosomal entanglements and increased bivalent formation compared with knockout alleles. Comparisons of RAD51 loadings and chromosomal entanglements in these single mutants, rad51c-3 rad51d-4, rad51c-3 dmc1a dmc1b, and rad51d-4 dmc1a dmc1b suggest that the retained level of RAD51 in mutants is required for uncovering their function in crossover formation. Reductions in chiasma frequency and later HEI10 foci in these mutants support that crossover maturation requires RAD51C and RAD51D. Moreover, interaction between RAD51D and MSH5 indicates that RAD51 paralogs may cooperate with MSH5 to ensure accurate Holliday junction processing into crossover products. This finding of the role of RAD51 paralogs in crossover control may be conserved from mammals to plants and advances our current understanding of these proteins.


Assuntos
Oryza , Animais , Oryza/genética , Oryza/metabolismo , Rad51 Recombinase/genética , Rad51 Recombinase/metabolismo , Meiose/genética , Recombinação Homóloga , Mamíferos
4.
New Phytol ; 237(6): 2422-2434, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36495065

RESUMO

The endonuclease methyl methanesulfonate and UV-sensitive protein 81 (MUS81) has been reported to participate in DNA repair during mitosis and meiosis. However, the exact meiotic function of MUS81 in rice remains unclear. Here, we use a combination of physiological, cytological, and genetic approaches to provide evidence that MUS81 functions in atypical recombination intermediate resolution rather than crossover designation in rice. Cytological and genetic analysis revealed that the total chiasma numbers in mus81 mutants were indistinguishable from wild-type. The numbers of HEI10 foci (the sites of interference-sensitive crossovers) in mus81 were also similar to that of wild-type. Moreover, disruption of MUS81 in msh5 or msh4 msh5 background did not further decrease chiasmata frequency, suggesting that rice MUS81 did not function in crossover designation. Mutation of FANCM and ZEP1 could enhance recombination frequency. Unexpectedly, chromosome fragments and bridges were frequently observed in mus81 zep1 and mus81 fancm, illustrating that MUS81 may resolve atypical recombination intermediates. Taken together, our data suggest that MUS81 contributes little to crossover designation but plays a crucial role in the resolution of atypical meiotic intermediates by working together with other anti-crossover factors.


Assuntos
Troca Genética , Oryza , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Oryza/genética , Oryza/metabolismo , Meiose/genética , Endonucleases/genética , Endonucleases/metabolismo
5.
Plant Cell ; 32(10): 3273-3289, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32732308

RESUMO

RNA-dependent RNA polymerase 6 (RDR6) is a core component of the small RNA biogenesis pathway, but its function in meiosis is unclear. Here, we report a new allele of OsRDR6 (Osrdr6-meiosis [Osrdr6-mei]), which causes meiosis-specific phenotypes in rice (Oryza sativa). In Osrdr6-mei, meiotic double-strand break (DSB) formation is partially blocked. We created a biallelic mutant with more severe phenotypes, Osrdr6-bi, by crossing Osrdr6-mei with a knockout mutant, Osrdr6-edit In Osrdr6-bi meiocytes, 24 univalents were observed, and no histone H2AX phosphorylation foci were detected. Compared with the wild type, the number of 21-nucleotide small RNAs in Osrdr6-mei was dramatically lower, while the number of 24-nucleotide small RNAs was significantly higher. Thousands of differentially methylated regions (DMRs) were discovered in Osrdr6-mei, implying that OsRDR6 plays an important role in DNA methylation. There were 457 genes downregulated in Osrdr6-mei, including three genes, CENTRAL REGION COMPONENT1, P31 comet , and O. sativa SOLO DANCERS, related to DSB formation. Interestingly, the downregulated genes were associated with a high level of 24-nucleotide small RNAs but less strongly associated with DMRs. Therefore, we speculate that the alteration in expression of small RNAs in Osrdr6 mutants leads to the defects in DSB formation during meiosis, which might not be directly dependent on RNA-directed DNA methylation.


Assuntos
Quebras de DNA de Cadeia Dupla , Reparo do DNA , Meiose , Oryza/genética , Proteínas de Plantas/genética , RNA Polimerase Dependente de RNA/genética , Metilação de DNA , Reparo do DNA/fisiologia , Regulação da Expressão Gênica de Plantas , Mutação , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , RNA de Plantas/biossíntese , RNA Polimerase Dependente de RNA/metabolismo
6.
FASEB J ; 36(5): e22289, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35436023

RESUMO

Previous studies have found that amphiregulin (AREG) may participate in eye elongation during the development of myopia, but the mechanism remains unclear. Here, we tested tear concentrations of AREG in adults and detected the role of AREG in scleral remodeling in form-deprivation myopia (FDM) in guinea pigs. We found the tear concentrations of AREG in myopes were significantly higher than those in emmetropes using enzyme-linked immunosorbent assay (ELISA). Tear concentrations of AREG were negatively correlated with spherical equivalent refraction and positively correlated with axial length (AL) and AL/corneal radii. We then used RNAi, DNA transfection and PD98059 treatments to determine the effects of AREG on extracellular signal-regulated kinase 1/2 (ERK1/2) and matrix metalloprotease-2 (MMP-2) in primary scleral fibroblasts (SFs). The hypothesis was further verified via loss- and gain-of-function experiments by intravitreal application of anti-AREG antibody (anti-AR) or AREG in form-deprivation eyes in guinea pigs. Immunofluorescence assay was used for cell type identification. Western-blot and q-PCR were used for the detection of relative expressions. Transmission electron microscopy was performed for posterior scleral observation. In vitro, we found AREG overexpression increased phospho-ERK1/2 and MMP-2 expression, while depletion of AREG inhibited their expressions. PD98059 (an effective ERK1/2 inhibitor) inhibited AREG-induced MMP-2 upregulation. In vivo, we found anti-AR treatments suppressed FDM by inhibiting scleral remodeling, while AREG treatments promoted FDM. Our results suggest that AREG in tear fluids can serve as a potential biomarker in myopes. AREG is involved in scleral remodeling through the ERK1/2-MMP-2 pathway. AREG is a potential target for myopia control.


Assuntos
Metaloproteinase 2 da Matriz , Miopia , Anfirregulina/metabolismo , Animais , Modelos Animais de Doenças , Cobaias , Sistema de Sinalização das MAP Quinases , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Miopia/genética
7.
Environ Res ; 233: 116472, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37348631

RESUMO

Inland waters are significant sources of atmospheric greenhouse gas (GHG) emissions. The thin boundary layer (TBL) model is often employed as a means of estimating GHG diffusion in inland waters based on gas transfer velocity (k) at the air-water interface, with k being subject to regulation by near-surface turbulence that is primarily driven by wind speed in many cases. This wind speed-based estimation of k (wind-k), however, can introduce substantial uncertainty for turbulent waterways where wind speed does not accurately represent overall turbulence. In this study, GHG diffusion in the Beijing-Hangzhou Grand Canal (China), the first and longest man-made canal in the world, was estimated using the TBL model, revealing that this model substantially underestimated GHG diffusion when relying on wind-k. Strikingly, the carbon dioxide, methane, and nitrous oxide diffusions were respectively underestimated by 159%, 162%, and 124% when using this model. These findings are significant for developing more reliable approaches to evaluate GHG emissions from inland waterways.


Assuntos
Gases de Efeito Estufa , Humanos , Dióxido de Carbono/análise , Vento , Metano/análise , China , Óxido Nitroso , Efeito Estufa
8.
Sensors (Basel) ; 23(15)2023 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-37571567

RESUMO

Respiratory rate and skin humidity are important physiological signals and have become an important basis for disease diagnosis, and they can be monitored by humidity sensors. However, it is difficult to employ high-quality humidity sensors on a broad scale due to their high cost and complex fabrication. Here, we propose a reliable, convenient, and efficient method to mass-produce humidity sensors. A capacitive humidity sensor is obtained by ablating a polyimide (PI) film with a picosecond laser to produce an interdigital electrode (IDE), followed by drop-casting graphene oxide (GO) as a moisture-sensitive material on the electrode. The sensor has long-time stability, a wide relative humidity (RH) detection range from 10% to 90%, and high sensitivity (3862 pF/%RH). In comparison to previous methods, the technology avoids the complex procedures and expensive costs of conventional interdigital electrode preparation. Furthermore, we discuss the effects of the electrode gap size and the amount of graphene oxide on humidity sensor performance, analyze the humidity sensing mechanism by impedance spectrum, and finally perform the monitoring of human respiratory rate and skin humidity change in a non-contact manner.


Assuntos
Grafite , Humanos , Umidade , Eletrodos , Lasers , Taxa Respiratória
9.
J Environ Sci (China) ; 125: 798-810, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36375961

RESUMO

Although point and nonpoint sources contribute roughly equal nutrient loads to lakes, their relative role in supporting algae growth has not been clarified. In this research, we have established a quantitative relationship between algae-available phosphorus (P) and P chemical fractions in sediments; the latter indicates the relative contribution of point versus nonpoint sources. Surface sediments from three large shallow lakes in eastern China, namely, the Chaohu, Taihu and Hongzehu Lakes, were sampled to assess their algae-available P and chemically extracted P fractions. The algae-available P primarily comes from iron/aluminium (hydr)oxide-bound P (Fe/Al-bound P), 45% of which is algae-available P. The ratio of Fe/Al-bound P to calcium compound-bound P (Ca-bound P) indicated the relative contribution of point to nonpoint sources, with the point sources contributing the majority of increased Fe/Al-bound P in sediments. Therefore, the reduction of point sources from urbanized areas, rather than nonpoint sources from agricultural areas that primarily contribute to the Ca-bound P fraction, should be prioritized to alleviate cyanobacterial algal blooms (CyanoHABs) in shallow lakes with sediment P as a potential source to support algae growth. With these important results, we proposed a conceptual model for "P-pumping suction" from sediments to algae to aid in the development of the criteria for sediment P concentrations in shallow lakes.


Assuntos
Lagos , Poluentes Químicos da Água , Fósforo/análise , Sedimentos Geológicos , Poluentes Químicos da Água/análise , Eutrofização , China , Monitoramento Ambiental
10.
Plant Physiol ; 187(3): 1605-1618, 2021 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-34618076

RESUMO

Replication protein A (RPA), a single-stranded DNA-binding protein, plays essential role in homologous recombination. However, because deletion of RPA causes embryonic lethality in mammals, the exact function of RPA in meiosis remains unclear. In this study, we generated an rpa1a mutant using CRISPR/Cas9 technology and explored its function in rice (Oryza sativa) meiosis. In rpa1a, 12 bivalents were formed at metaphase I, just like in wild-type, but chromosome fragmentations were consistently observed at anaphase I. Fluorescence in situ hybridization assays indicated that these fragmentations were due to the failure of the recombination intermediates to resolve. Importantly, the mutant had a highly elevated chiasma number, and loss of RPA1a could completely restore the 12 bivalent formations in the zmm (for ZIP1-4, MSH4/5, and MER3) mutant background. Protein-protein interaction assays showed that RPA1a formed a complex with the methyl methansulfonate and UV sensitive 81 (and the Fanconi anemia complementation group M-Bloom syndrome protein homologs (RECQ4A)-Topoisomerase3α-RecQ-mediated genome instability 1 complex to regulate chiasma formation and processing of the recombination intermediates. Thus, our data establish a pivotal role for RPA1a in promoting the accurate resolution of recombination intermediates and in limiting redundant chiasma formation during rice meiosis.


Assuntos
Proteínas de Ligação a DNA/genética , Meiose , Oryza/genética , Proteínas de Plantas/genética , Proteína de Replicação A/genética , Proteínas de Ligação a DNA/metabolismo , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Proteína de Replicação A/metabolismo
11.
Langmuir ; 38(8): 2467-2477, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35179898

RESUMO

Low-rank coal (LRC) contains large amounts of harmful impurities that must be processed before utilization. Flotation is an effective means for separating fine particles, which can be influenced by air solubility in water. In this work, deaerated water (DW), ordinary water (OW), and pressurized water (PW) were prepared to research the underlying mechanism of the effect of air solubility on the flotation performance of LRC. The results show that PW dissolves the greatest amount of air in the three kinds of water (DW, OW, and PW). The flotation performance of LRC in different water types is directly proportional to air solubility in aqueous solutions. In addition, the induction time of LRC in PW (600 ms) is significantly shorter than those in OW (1200 ms) and DW (4000 ms). Atomic force microscopy (AFM) studies reveal that typical interfacial nanobubbles (NBs) only form on a highly oriented pyrolytic graphite (HOPG) surface in PW due to the supersaturated air in water. Furthermore, the interaction between LRC particles and HOPG in PW is significantly stronger than those in both OW and DW, which is attributed to the capillary force of rgw nanobubble bridge formed between particles. The hydrophobic interaction enhanced by NBs is critically important for the attachment of LRC particles to macrobubbles in flotation. Overall, air solubility in water has a great effect on LRC flotation performance, and PW flotation technology can be extended to LRC purification.

12.
BMC Ophthalmol ; 22(1): 49, 2022 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-35109804

RESUMO

PURPOSE: To explore functional connectivity density (FCD) values of brain areas in children with strabismus and amblyopia (SA) based on blood oxygen level-dependent (BOLD) signals. METHODS: This study recruited 26 children (14 male, 12 females) with SA and 26 healthy children (14 male, 12 female) as healthy controls (HCs). Both groups matched in age, gender, educational level and socioeconomic background. While resting, all participants underwent fMRI scanning and global FCD (gFCD) and local FCD (lFCD) values were calculated. Receiver operating characteristic (ROC) curves were created to investigate whether there was a significant difference between children with SA and healthy controls. RESULTS: When compared with healthy controls, children with SA had significantly lower gFCD values in the right cerebellum, left putamen, and right superior frontal gyrus; however, the same metrics showed opposite changes in the right angular gyrus, left middle cingulate gyrus, left angular gyrus, right superior parietal gyrus, and right middle frontal gyrus. In children with SA, lFCD values were found to be remarkably decreased in regions of the middle right temporal pole, right cerebellum, left putamen, left hippocampus, right hippocampus, left thalamus, left cerebellum; values were increased in the right superior parietal gyrus as compared with healthy controls. CONCLUSION: We noted abnormal neural connectivity in some brain areas of children with SA; detailing such connectivity aberrations is useful in exploring the pathophysiology of SA and providing useful information for future clinical management.


Assuntos
Ambliopia , Estrabismo , Ambliopia/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Estudos de Casos e Controles , Criança , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino
13.
Proc Natl Acad Sci U S A ; 116(32): 15967-15972, 2019 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-31341087

RESUMO

The organization of microtubules into a bipolar spindle is essential for chromosome segregation. Both centrosome and chromatin-dependent spindle assembly mechanisms are well studied in mouse, Drosophila melanogaster, and Xenopus oocytes; however, the mechanism of bipolar spindle assembly in plant meiosis remains elusive. According to our observations of microtubule assembly in Oryza sativa, Zea mays, Arabidopsis thaliana, and Solanum lycopersicum, we propose that a key step of plant bipolar spindle assembly is the correction of the multipolar spindle into a bipolar spindle at metaphase I. The multipolar spindles failed to transition into bipolar ones in OsmtopVIB with the defect in double-strand break (DSB) formation. However, bipolar spindles were normally assembled in several other mutants lacking DSB formation, such as Osspo11-1, pair2, and crc1, indicating that bipolar spindle assembly is independent of DSB formation. We further revealed that the mono-orientation of sister kinetochores was prevalent in OsmtopVIB, whereas biorientation of sister kinetochores was frequently observed in Osspo11-1, pair2, and crc1 In addition, mutations of the cohesion subunit OsREC8 resulted in biorientation of sister kinetochores as well as bipolar spindles even in the background of OsmtopVIB Therefore, we propose that biorientation of the kinetochore is required for bipolar spindle assembly in the absence of homologous recombination.


Assuntos
Meiose , Oryza/citologia , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Fuso Acromático/metabolismo , Quebras de DNA de Cadeia Dupla , Haploidia , Cinetocoros/metabolismo , Modelos Biológicos , Mutação/genética
14.
Medicina (Kaunas) ; 58(12)2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36556951

RESUMO

BACKGROUND AND OBJECTIVES: Hypericum perforatum (HP) is widely used for depressive therapy. Nevertheless, the antidepressant effect and potential mechanism of hyperoside (Hyp), the main active component of HP, have not been determined. MATERIALS AND METHODS: We performed ultra-performance liquid chromatography-quadrupole-time-of-flight-tandem mass spectrometry (UPLC-Q-TOF-MS/MS) technology to analyze the components in HP. Using data mining and network pharmacology methods, combined with Cytoscape v3.7.1 and other software, the active components, drug-disease targets, and key pathways of HP in the treatment of depression were evaluated. Finally, the antidepressant effects of Hyp and the mechanism involved were verified in chronic-stress-induced mice. RESULTS: We identified 12 compounds from HP. Hyp, isoquercetin, and quercetin are the main active components of HP. The Traditional Chinese Medicine Systems Pharmacology Database (TCMSP), the Analysis Platform, DrugBank, and other databases were analyzed using data mining, and the results show that the active components of HP and depression are linked to targets such as TNF-, IL-2, TLR4, and so on. A potential signaling pathway that was most relevant to the antidepressant effects of Hyp is the C-type lectin receptor signaling pathway. Furthermore, the antidepressant effects of Hyp were examined, and it is verified for the first time that Hyp significantly alleviated depressive-like behaviors in chronic-stress-induced mice, which may be mediated by inhibiting the NLRP1 inflammasome through the CXCL1/CXCR2/BDNF signaling pathway. CONCLUSION: Hyp is one of the main active components of HP, and Hyp has antidepressant effects through the NLRP1 inflammasome, which may be connected with the CXCL1/CXCR2/BDNF signaling pathway.


Assuntos
Depressão , Inflamassomos , Camundongos , Animais , Depressão/tratamento farmacológico , Quercetina/uso terapêutico , Espectrometria de Massas em Tandem/métodos , Fator Neurotrófico Derivado do Encéfalo , Antidepressivos/farmacologia , Antidepressivos/uso terapêutico
15.
Anal Chem ; 93(13): 5355-5359, 2021 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-33759498

RESUMO

We describe the incorporation of gated ion channels into probes for scanning ion conductance microscopy (SICM) as a robust platform for collecting spatial information at interfaces. Specifically, a dual-barrel pipet is used, where one barrel controls the pipet position and the second barrel houses voltage-gated transient receptor potential vanilloid 1 (TRPV1) channels excised in a sniffer-patch configuration. Spatially resolved sensing with TRPV1 channels is demonstrated by imaging a porous membrane where a transmembrane potential across the membrane generates local electric field gradients at pores that activate TRPV1 channels when the probe is in the vicinity of the pore. The scanning routine and automated signal analysis demonstrated provide a generalizable approach to employing gated ion channels as sensors for imaging applications.


Assuntos
Canais Iônicos , Microscopia , Porosidade
16.
New Phytol ; 230(2): 585-600, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33421144

RESUMO

The bipolar spindle structure in meiosis is essential for faithful chromosome segregation. PUTATIVE RECOMBINATION INITIATION DEFECT 1 (PRD1) previously has been shown to participate in the formation of DNA double strand breaks (DSBs). However, the role of PRD1 in meiotic spindle assembly has not been elucidated. Here, we reveal by both genetic analysis and immunostaining technology that PRD1 is involved in spindle assembly in rice (Oryza sativa) meiosis. We show that DSB formation and bipolar spindle assembly are disturbed in prd1 meiocytes. PRD1 signals display a dynamic pattern of localization from covering entire chromosomes at leptotene to congregating at the centromere region after leptotene. Centromeric localization of PRD1 signals depends on the organization of leptotene chromosomes, but not on DSB formation and axis establishment. PRD1 exhibits interaction and co-localization with several kinetochore components. We also find that bi-orientation of sister kinetochores within a univalent induced by mutation of REC8 can restore bipolarity in prd1. Furthermore, PRD1 directly interacts with REC8 and SGO1, suggesting that PRD1 may play a role in regulating the orientation of sister kinetochores. Taken together, we speculate that PRD1 promotes bipolar spindle assembly, presumably by modulating the orientation of sister kinetochores in rice meiosis.


Assuntos
Oryza , Segregação de Cromossomos/genética , Recombinação Homóloga , Cinetocoros , Meiose , Oryza/genética , Fatores de Iniciação de Peptídeos , Fuso Acromático
17.
Plant Cell ; 30(12): 3024-3037, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30538156

RESUMO

Response regulators play significant roles in controlling various biological processes; however, their roles in plant meiosis remain unclear. Here, we report the identification of OsRR24/LEPTOTENE1 (LEPTO1), a rice (Oryza sativa) type-B response regulator that participates in the establishment of key molecular and morphological features of chromosomes in leptotene, an early stage of prophase I in meiosis. Although meiosis initiates normally, as indicated by staining of the centromere-specific histone CENH3, the meiotic chromosomes in lepto1 mutant pollen mother cells fail to form the thin thread-like structures that are typical of leptotene chromosomes in wild-type pollen mother cells. Furthermore, lepto1 mutants fail to form chromosomal double-strand breaks, do not recruit meiosis-specific proteins to the meiotic chromosomes, and show disrupted callose deposition. LEPTO1 also is essential for programmed cell death in tapetal cells. LEPTO1 contains a conserved signal receiver domain (DDK) and a myb-like DNA binding domain at the N terminus. LEPTO1 interacts with two authentic histidine phosphotransfer (AHP) proteins, OsAHP1 and OsAHP2, via the DDK domain, and a phosphomimetic mutation of the DDK domain relieves its repression of LEPTO1 transactivation activity. Collectively, our results show that OsRR24/LEPTO1 plays a significant role in the leptotene phase of meiotic prophase I.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Meiose/genética , Proteínas Nucleares/metabolismo , Oryza/genética , Proteínas de Ciclo Celular/genética , Cromossomos de Plantas/genética , Meiose/fisiologia , Prófase Meiótica I/genética , Prófase Meiótica I/fisiologia , Proteínas Nucleares/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Pólen/genética , Pólen/metabolismo
18.
Med Sci Monit ; 27: e930588, 2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34388144

RESUMO

BACKGROUND By using functional magnetic resonance imaging (fMRI), we aimed to study the changes in potential brain function network activity in patients with acute eye pain. Also, by using the voxel-wise degree centrality (DC) method, we aimed to explore the relationship between spontaneous brain activity and the clinical features of patients with acute eye pain. MATERIAL AND METHODS A total of 15 patients with acute eye pain (5 women and 10 men; EP group) and 15 healthy controls (5 women and 10 men; HC group), were scanned by fMRI. The DC method was used to evaluate changes in spontaneous brain activity. Receiver operating characteristic (ROC) curves were analyzed, and Pearson correlation analysis was used to study the relationship between DC values and clinical manifestations in different regions of brain. RESULTS The area of the left limbic lobe showed a reduction in DC value in patients in the EP group. DC values were elevated in the left cerebellum posterior lobe, left inferior parietal lobule, left inferior temporal gyrus, left precuneus, and right cerebellum posterior lobe in the EP group. The visual analog scale value of the eyes in the EP group was negatively correlated with the left limbic lobe signal value and positively correlated with the left inferior parietal lobule signal value. Further, the scores of the hospital anxiety and depression scale and DC value of the left limbic lobe were negatively correlated. CONCLUSIONS Compared with the HC group, patients with acute eye pain had abnormal patterns of intrinsic brain activity in different brain regions, which may help reveal the potential neural mechanisms involved in eye pain.


Assuntos
Conectoma/métodos , Dor Ocular/diagnóstico por imagem , Dor Ocular/fisiopatologia , Adulto , Encéfalo/fisiopatologia , Mapeamento Encefálico/métodos , Olho/patologia , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Rede Nervosa/fisiopatologia , Curva ROC , Descanso
19.
BMC Ophthalmol ; 21(1): 255, 2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-34107904

RESUMO

BACKGROUND: Previous studies have demonstrated that strabismus amblyopia can result in markedly brain function alterations. However, the differences in spontaneous brain activities of strabismus amblyopia (SA) patients still remain unclear. Therefore, the current study intended to employthe voxel-mirrored homotopic connectivity (VMHC) method to investigate the intrinsic brain activity changes in SA patients. PURPOSE: To investigate the changes in cerebral hemispheric functional connections in patients with SA and their relationship with clinical manifestations using the VMHC method. MATERIAL AND METHODS: In the present study, a total of 17 patients with SA (eight males and nine females) and 17 age- and weight-matched healthy control (HC) groups were enrolled. Based on the VMHC method, all subjects were examined by functional magnetic resonance imaging. The functional interaction between cerebral hemispheres was directly evaluated. The Pearson's correlation test was used to analyze the clinical features of patients with SA. In addition, their mean VMHC signal values and the receiver operating characteristic curve were used to distinguish patients with SA and HC groups. RESULTS: Compared with HC group, patients with SA had higher VMHC values in bilateral cingulum ant, caudate, hippocampus, and cerebellum crus 1. Moreover, the VMHC values of some regions were positively correlated with some clinical manifestations. In addition, receiver operating characteristic curves presented higher diagnostic value in these areas. CONCLUSION: SA subjects showed abnormal brain interhemispheric functional connectivity in visual pathways, which might give some instructive information for understanding the neurological mechanisms of SA patients.


Assuntos
Ambliopia , Imageamento por Ressonância Magnética , Encéfalo , Feminino , Humanos , Masculino , Fibras Nervosas
20.
PLoS Genet ; 14(11): e1007769, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30419020

RESUMO

Meiotic cytokinesis influences the fertility and ploidy of gametes. However, limited information is available on the genetic control of meiotic cytokinesis in plants. Here, we identified a rice mutant with low male fertility, defective callose in meiosis 1 (dcm1). The pollen grains of dcm1 are proved to be defective in exine formation. Meiotic cytokinesis is disrupted in dcm1, resulting in disordered spindle orientation during meiosis II and formation of pollen grains with varied size and DNA content. We demonstrated that meiotic cytokinesis defect in dcm1 is caused by prematurely dissolution of callosic plates. Furthermore, peripheral callose surrounding the dcm1 pollen mother cells (PMCs) also disappeared untimely around pachytene. The DCM1 protein contains five tandem CCCH motifs and interacts with nuclear poly (A) binding proteins (PABNs) in nuclear speckles. The expression profiles of genes related to callose synthesis and degradation are significantly modified in dcm1. Together, we propose that DCM1 plays an essential role in male meiotic cytokinesis by preserving callose from prematurely dissolution in rice.


Assuntos
Glucanos/metabolismo , Oryza/citologia , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Sequência de Aminoácidos , Núcleo Celular/metabolismo , Citocinese/genética , Citocinese/fisiologia , Técnicas de Inativação de Genes , Genes de Plantas , Meiose/genética , Meiose/fisiologia , Oryza/genética , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Pólen/citologia , Pólen/genética , Pólen/metabolismo , Proteínas de Ligação a Poli(A)/metabolismo , Homologia de Sequência de Aminoácidos , Sequências de Repetição em Tandem , Dedos de Zinco/genética
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