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1.
Nat Chem Biol ; 19(9): 1097-1104, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36959461

RESUMO

The global regulation of cell growth rate on gene expression perturbs the performance of gene networks, which would impose complex variations on the cell-fate decision landscape. Here we use a simple synthetic circuit of mutual repression that allows a bistable landscape to examine how such global regulation would affect the stability of phenotypic landscape and the accompanying dynamics of cell-fate determination. We show that the landscape experiences a growth-rate-induced bifurcation between monostability and bistability. Theoretical and experimental analyses reveal that this bifurcating deformation of landscape arises from the unbalanced response of gene expression to growth variations. The path of growth transition across the bifurcation would reshape cell-fate decisions. These results demonstrate the importance of growth regulation on cell-fate determination processes, regardless of specific molecular signaling or regulation.


Assuntos
Redes Reguladoras de Genes , Transdução de Sinais , Diferenciação Celular/fisiologia , Proliferação de Células
2.
Drug Resist Updat ; 72: 101017, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37988981

RESUMO

The role of ABCC4, an ATP-binding cassette transporter, in the process of platelet formation, megakaryopoiesis, is unknown. Here, we show that ABCC4 is highly expressed in megakaryocytes (MKs). Mining of public genomic data (ATAC-seq and genome wide chromatin interactions, Hi-C) revealed that key megakaryopoiesis transcription factors (TFs) interacted with ABCC4 regulatory elements and likely accounted for high ABCC4 expression in MKs. Importantly these genomic interactions for ABCC4 ranked higher than for genes with known roles in megakaryopoiesis suggesting a role for ABCC4 in megakaryopoiesis. We then demonstrate that ABCC4 is required for optimal platelet formation as in vitro differentiation of fetal liver derived MKs from Abcc4-/- mice exhibited impaired proplatelet formation and polyploidization, features required for optimal megakaryopoiesis. Likewise, a human megakaryoblastic cell line, MEG-01 showed that acute ABCC4 inhibition markedly suppressed key processes in megakaryopoiesis and that these effects were related to reduced cAMP export and enhanced dissociation of a negative regulator of megakaryopoiesis, protein kinase A (PKA) from ABCC4. PKA activity concomitantly increased after ABCC4 inhibition which was coupled with significantly reduced GATA-1 expression, a TF needed for optimal megakaryopoiesis. Further, ABCC4 protected MKs from 6-mercaptopurine (6-MP) as Abcc4-/- mice show a profound reduction in MKs after 6-MP treatment. In total, our studies show that ABCC4 not only protects the MKs but is also required for maximal platelet production from MKs, suggesting modulation of ABCC4 function might be a potential therapeutic strategy to regulate platelet production.


Assuntos
Plaquetas , Megacariócitos , Animais , Humanos , Camundongos , Transportadores de Cassetes de Ligação de ATP/metabolismo , Plaquetas/metabolismo , Diferenciação Celular , Megacariócitos/metabolismo , Mercaptopurina/farmacologia , Mercaptopurina/metabolismo , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo
3.
Immunology ; 172(4): 566-576, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38618995

RESUMO

The inflammatory response is tightly regulated to eliminate invading pathogens and avoid excessive production of inflammatory mediators and tissue damage. Caspase-8 is a cysteine protease that is involved in programmed cell death. Here we show the TRIF-RIPK1-Caspase-8 is required for LPS-induced CYLD degradation in macrophages. TRIF functions in the upstream of RIPK1. The homotypic interaction motif of TRIF and the death domain of RIPK1 are essential for Caspase-8 activation. Caspase-8 cleaves CYLD and the D235A mutant is resistant to the protease activity of Caspase-8. TRIF and RIPK1 serve as substrates of Capase-8 in vitro. cFLIP interacts with Caspase-8 to modulate its protease activity on CYLD and cell death. Deficiency in TRIF, Caspase-8 or CYLD can lead to a decrease or increase in the expression of genes encoding inflammatory cytokines. Together, the TRIF-Caspase-8 and CYLD play opposite roles in the regulation of TLR4 signalling.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular , Caspase 8 , Enzima Desubiquitinante CYLD , Lipopolissacarídeos , Proteína Serina-Treonina Quinases de Interação com Receptores , Transdução de Sinais , Receptor 4 Toll-Like , Caspase 8/metabolismo , Caspase 8/genética , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Proteínas Adaptadoras de Transporte Vesicular/genética , Receptor 4 Toll-Like/metabolismo , Receptor 4 Toll-Like/genética , Enzima Desubiquitinante CYLD/metabolismo , Enzima Desubiquitinante CYLD/genética , Animais , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Camundongos , Humanos , Regulação da Expressão Gênica , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos Knockout , Camundongos Endogâmicos C57BL , Proteína de Domínio de Morte Associada a Fas
4.
Cereb Cortex ; 33(21): 10770-10783, 2023 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-37727985

RESUMO

It is well known that functional magnetic resonance imaging (fMRI) is a widely used tool for studying brain activity. Recent research has shown that fluctuations in fMRI data can reflect functionally meaningful patterns of brain activity within the white matter. We leveraged resting-state fMRI from an adolescent population to characterize large-scale white matter functional gradients and their formation during adolescence. The white matter showed gray-matter-like unimodal-to-transmodal and sensorimotor-to-visual gradients with specific cognitive associations and a unique superficial-to-deep gradient with nonspecific cognitive associations. We propose two mechanisms for their formation in adolescence. One is a "function-molded" mechanism that may mediate the maturation of the transmodal white matter via the transmodal gray matter. The other is a "structure-root" mechanism that may support the mutual mediation roles of the unimodal and transmodal white matter maturation during adolescence. Thus, the spatial layout of the white matter functional gradients is in concert with the gray matter functional organization. The formation of the white matter functional gradients may be driven by brain anatomical wiring and functional needs.


Assuntos
Substância Branca , Adolescente , Humanos , Substância Branca/patologia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Substância Cinzenta/patologia , Imageamento por Ressonância Magnética , Mapeamento Encefálico/métodos
5.
Small ; 19(42): e2301163, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37267935

RESUMO

Microvascular networks are essential for the efficient transport of nutrients, waste products, and drugs throughout the body. Wire-templating is an accessible method for generating laboratory models of these blood vessel networks, but it has difficulty fabricating microchannels with diameters of ten microns and narrower, a requirement for modeling human capillaries. This study describes a suite of surface modification techniques to  selectively control the interactions amongst wires, hydrogels, and world-to-chip interfaces. This wire templating method enables the fabrication of perfusable hydrogel-based rounded cross-section capillary-scale networks whose diameters controllably narrow at bifurcations down to 6.1 ± 0.3 microns in diameter. Due to its low cost, accessibility, and compatibility with a wide range of common hydrogels of tunable stiffnesses such as collagen, this technique may increase the fidelity of experimental models of capillary networks for the study of human health and disease.


Assuntos
Capilares , Hidrogéis , Humanos , Engenharia Tecidual/métodos
6.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 45(1): 124-128, 2023 Feb.
Artigo em Zh | MEDLINE | ID: mdl-36861165

RESUMO

Epigenetics refers to heritable changes in gene expression and function without alterations in gene sequences,including DNA methylation,histone modification,and non-coding RNAs.Endometriosis is a benign gynecological disease that affects the fertility and health of reproductive-age women,the etiology of which remains unclear.The recent studies have demonstrated that epigenetics plays a key role in the occurrence and development of endometriosis.This article reviews the research progress in the regulatory mechanism and application of epigenetics in endometriosis.


Assuntos
Endometriose , Feminino , Humanos , Endometriose/genética , Epigênese Genética , Metilação de DNA , Processamento de Proteína Pós-Traducional
7.
Neuroimage ; 260: 119482, 2022 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-35842101

RESUMO

Cognitive and psychological development during adolescence is different from one another, which is rooted in individual differences in maturational changes in the adolescent brain. This study employed multi-modal MRI data and characterized interindividual variability in functional connectivity (IVFC) and its associations with cognition and psychopathology using the Philadelphia Neurodevelopmental Cohort (PNC) of 755 youth. We employed resting state functional MRI (rs-fMRI) and diffusion weighted images (DWIs) to estimate brain structural and functional networks. We computed the IVFC of individuals and examined its relation with structural and functional organizations. We further employed sparse partial least squares (sparse-PLS) and meta-analysis to examine the developmental associations of the IVFC with cognition and transdiagnostic dimensions of psychopathology in early, middle, and late adolescence. Our results revealed that the IVFC spatial topography reflects the brain functional integration and structure-function decoupling. Age effects on the IVFC of association networks were mediated by the FC among the triple networks, including frontoparietal, salience, and default mode networks (DMN), while those of primary and cerebellar networks were mediated by the cerebello-cortical FC. The IVFC of the triple and cerebellar networks explained the variance of executive functions and externalizing behaviors in early adolescence and then the variance of emotion and internalizing and psychosis in middle and late adolescence. We further evaluated this finding via meta-analysis on task-based studies on cognition and psychopathology. These findings implicate the emerging importance of the IVFC of the triple and cerebellar networks in cognitive, emotional, and psychopathological development during adolescence.


Assuntos
Cognição , Transtornos Psicóticos , Adolescente , Encéfalo , Mapeamento Encefálico/métodos , Humanos , Imageamento por Ressonância Magnética/métodos
8.
Reproduction ; 164(5): 231-241, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-35900339

RESUMO

In brief: Insufficient trophoblast invasion at the maternal-fetal interface contributes to abortion-prone pregnancy. Our study shows that decreased levels of IGFBP7 in unexplained recurrent spontaneous abortion (URSA) trophoblast cells inhibit MMP2 and Slug expression as well as trophoblast invasion, suggesting that IGFBP7 should be considered a potential therapeutic protein target in URSA. Abstract: Insufficient trophoblast invasion at the maternal-fetal interface contributes to abortion-prone pregnancy. Cyclosporine A (CsA) can exert therapeutic effects on URSA by promoting trophoblast invasion. A previous study showed decreased expression of insulin-like growth factor-binding protein 7 (IGFBP7) in the sera of recurrent spontaneous abortion patients. However, the role of IGFBP7 in URSA remains unknown. The aim of this study was to determine whether IGFBP7 modulates trophoblast invasion in URSA and the underlying molecular mechanisms. We found that IGFBP7 was expressed at lower levels in villous specimens from URSA patients. Manipulating IGFBP7 expression significantly affected the MMP2 and Slug expression in HTR-8/SVneo cells as well as trophoblast invasion in vitro. Inactivation of IGF-1R by IGFBP7 was observed, and IGF-1R inhibition increased the IGFBP7-induced MMP2 and Slug expression in HTR-8/SVneo cells. Moreover, the level of c-Jun was significantly upregulated in the URSA group. Silencing IGFBP7 increased the binding of downstream c-Jun to the MMP2 and Slug promoter regions in HTR-8/SVneo cells, thus suppressing transcription. In addition, increased expression of IGFBP7 in HTR-8/SVneo cells was observed upon CsA treatment. Knockdown of IGFBP7 inhibited the CsA-enhanced MMP2 and Slug expression in HTR-8/SVneo cells. Our results suggest that in normal pregnancy, IGFBP7 induces MMP2 and Slug expression via the IGF-1R-mediated c-Jun signaling pathway, thereby promoting trophoblast invasion. IGFBP7 depletion in URSA inhibits MMP2 and Slug expression as well as trophoblast invasion. Moreover, IGFBP7 participates in CsA-induced trophoblast invasion, suggesting that IGFBP7 is a potential therapeutic target for URSA.


Assuntos
Aborto Habitual , Aborto Espontâneo , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina , Aborto Habitual/metabolismo , Aborto Espontâneo/metabolismo , Movimento Celular , Ciclosporina/farmacologia , Feminino , Humanos , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/genética , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/metabolismo , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Gravidez , Proteínas Proto-Oncogênicas c-jun/metabolismo , Receptor IGF Tipo 1/metabolismo , Transdução de Sinais , Trofoblastos/metabolismo
9.
BMC Med Res Methodol ; 22(1): 137, 2022 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-35562672

RESUMO

BACKGROUND: With the spread of COVID-19, the time-series prediction of COVID-19 has become a research hotspot. Unlike previous epidemics, COVID-19 has a new pattern of long-time series, large fluctuations, and multiple peaks. Traditional dynamical models are limited to curves with short-time series, single peak, smoothness, and symmetry. Secondly, most of these models have unknown parameters, which bring greater ambiguity and uncertainty. There are still major shortcomings in the integration of multiple factors, such as human interventions, environmental factors, and transmission mechanisms. METHODS: A dynamical model with only infected humans and removed humans was established. Then the process of COVID-19 spread was segmented using a local smoother. The change of infection rate at different stages was quantified using the continuous and periodic Logistic growth function to quantitatively describe the comprehensive effects of natural and human factors. Then, a non-linear variable and NO2 concentrations were introduced to qualify the number of people who have been prevented from infection through human interventions. RESULTS: The experiments and analysis showed the R2 of fitting for the US, UK, India, Brazil, Russia, and Germany was 0.841, 0.977, 0.974, 0.659, 0.992, and 0.753, respectively. The prediction accuracy of the US, UK, India, Brazil, Russia, and Germany in October was 0.331, 0.127, 0.112, 0.376, 0.043, and 0.445, respectively. CONCLUSION: The model can not only better describe the effects of human interventions but also better simulate the temporal evolution of COVID-19 with local fluctuations and multiple peaks, which can provide valuable assistant decision-making information.


Assuntos
COVID-19 , Brasil/epidemiologia , COVID-19/epidemiologia , Humanos , Índia/epidemiologia , Pandemias , SARS-CoV-2
10.
BMC Infect Dis ; 22(1): 771, 2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-36195855

RESUMO

BACKGROUND AND OBJECTIVES: Bloodstream infection (BSI) is a life-threatening condition in critically ill patients, but pathogen quantification techniques during treatment are laborious. This study aimed to explore the impact of monitoring pathogen DNA load changes and polymicrobial infection in blood by droplet digital polymerase chain reaction (ddPCR) on the prognosis of patients with BSIs. METHODS: This prospective case series study was conducted in the general intensive care unit of the Zhejiang Provincial People's Hospital and included patients with BSIs from May 2020 to January 2021. Pathogens DNA load and presence of polymicrobial BSIs were dynamically monitored by ddPCR. RESULTS: Sixteen patients with BSIs proven by blood culture were recruited (87.5% men; mean age, 69.3 ± 13.7 years). All pathogens identified by blood culture were Gram-negative bacteria, among which seven were multidrug-resistant strains. The 28-day mortality rate was 62.5%. Compared to the 28-day survivors, the non-survivors were older (P = 0.04), had higher pathogen DNA load on the second (day 3-4) and third (day 6-7) ddPCR assay (P < 0.01 in both cases). In addition, the changes of pathogen DNA load in the 28-day survivors had a downward trend in the first three ddPCR assay, whereas stable load or an upward trend was observed in the 28-day non-survivors. Moreover, the number of pathogen species in patients with BSIs in the 28-day survivors decreased during the period of effective antibiotic treatment. CONCLUSION: The changes of pathogen DNA load and species monitored in blood by ddPCR may be used to determine antibiotic efficacy and make a more accurate prognostic assessment in patients with BSIs.


Assuntos
Bacteriemia , Sepse , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/uso terapêutico , Bacteriemia/diagnóstico , Bacteriemia/tratamento farmacológico , Bacteriemia/microbiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase/métodos , Estudos Prospectivos , Sepse/tratamento farmacológico
11.
BMC Nurs ; 21(1): 210, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35915490

RESUMO

BACKGROUND: Nasopharyngeal carcinoma (NPC) is one of the most common head and neck malignancies, having a high incidence in Guangxi, China. Although chemoradiotherapy offers more effective cancer treatment, it also causes a variety of acute and chronic side effects, seriously affecting the quality of life. NPC has evolved into a chronic disease with most patients opting for home-based rehabilitation. Therefore, efforts on improving the home-based extended care services to improve the quality of life of patients are booming. The Chinese government encourages the use of internet technology for expanding the prospect of nursing. This study aimed to evaluate the impact of a mHealth-based care model on the health outcomes of discharged patients with nasopharyngeal carcinoma. METHODS: An experimental design was applied for this study. The study enrolled 116 discharged patients who were re-examined in the Radiotherapy Department of the First Affiliated Hospital of Guangxi Medical University from November 2019 to February 2020. These patients were randomized into control and intervention groups (n = 58 per group), but during the implementation of the project, there was one dropout in the control group due to the loss of follow-up, and one dropout in the intervention group due to distant metastasis. In the end, 57 patients in the control and intervention groups completed the trial. The control group was subjected to routine discharge guidance and follow-up, while the experimental group was implemented with a mobile health (mHealth)-based continuous nursing intervention model. The scores of the side effects, cancer fatigue, and quality of life were compared between the two groups of patients for 3, 6, and 12 months, respectively after discharge from the hospital. RESULTS: This study included 114 patients and there were no significant differences in the baseline data between the two groups. After 6 and 12 months of intervention, the severity of radiation toxicity and side effects, the scores of cancer-related fatigue, and quality of life (symptom field) of the patients in the interventional group were significantly lowered statistically compared to those in the control group. CONCLUSION: This study is based on the mHealth continuous nursing intervention model, which can reduce the side effects of radiotherapy and cancer fatigue, and improve the quality of life. TRIAL REGISTRATION: This study was retrospectively registered as a randomized controlled trial in the Chinese Clinical Trial Center. Registration Date: January 12, 2021, Registration Number: ChiCTR2100042027.

12.
Neuroimage ; 245: 118716, 2021 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-34767941

RESUMO

The developing brain grows exponentially in the first few years of life. There is a need to have age-appropriate brain atlases that coherently characterize the geometry of the cerebral cortex, white matter tracts, and functional organization. This study employed multi-modal brain images of an Asian cohort and constructed brain structural and functional atlases for 6-month-old infants, 4.5-, 6-, and 7.5-year-old children. We exploited large deformation diffeomorphic metric mapping and probabilistic atlas generation approaches to integrate structural MRI and diffusion weighted images (DWIs) and to create the atlas where white matter tracts well fit into the cortical folding pattern. Based on this structural atlas, we then employed spectral clustering to parcellate the brain into functional networks from resting-state fMRI (rs-fMRI). Our results provided the atlas that characterizes the cortical folding geometry, subcortical regions, deep white matter tracts, as well as functional networks in a stereotaxic coordinate space for the four different age groups. The functional networks consisting of the primary cortex were well established in infancy and remained stable to childhood, while specific higher-order functional networks showed specific patterns of hemispherical, subcortical-cerebellar, and cortical-cortical integration and segregation from infancy to childhood. Our multi-modal fusion analysis demonstrated the use of the integrated structural and functional atlas for understanding coherent patterns of brain anatomical and functional development during childhood. Hence, our atlases can be potentially used to study coherent patterns of brain anatomical and functional development.


Assuntos
Atlas como Assunto , Encéfalo/diagnóstico por imagem , Encéfalo/crescimento & desenvolvimento , Imageamento por Ressonância Magnética , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Valores de Referência , Singapura
13.
Biol Reprod ; 105(1): 128-136, 2021 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-33693540

RESUMO

Endometriosis is an estrogen-dependent disease. Our previous study demonstrated that elevated levels of transcription factor 21 (TCF21) in endometriotic tissues enhanced steroidogenic factor-1 (SF-1) and estrogen receptor ß (ERß) expression by forming a heterodimer with upstream stimulatory factor 2 (USF2), allowing these TCF21/USF2 complexes to bind to the promoters of SF-1 and ERß. Furthermore, TCF21 contributed to the increased proliferation of endometriotic stromal cells (ESCs), suggesting that TCF21 may play a vital role in the pathogenesis of endometriosis. SUMOylation is a posttranslational modification that has emerged as a crucial molecular regulatory mechanism. However, the mechanism regulating TCF21 SUMOylation in endometriosis is incompletely characterized. Thus, this study aimed to explore the effect of TCF21 SUMOylation on its expression and regulation in ovarian endometriosis. We found that the levels of SUMOylated TCF21 were increased in endometriotic tissues and stromal cells compared with eutopic endometrial tissues and stromal cells and enhanced by estrogen. Treatment with the SUMOylation inhibitor ginkgolic acid and the results of a protein half-life assay demonstrated that SUMOylation can stabilize the TCF21 protein. A coimmunoprecipitation assay showed that SUMOylation probably increased its interaction with USF2. Further analyses elucidated that SUMOylation of TCF21 significantly increased the binding activity of USF2 to the SF-1 and ERß promoters. Moreover, the SUMOylation motifs in TCF21 affected the proliferation ability of ESCs. The results of this study suggest that SUMOylation plays a critical role in mediating the high expression of TCF21 in ESCs and may participate in the development of endometriosis.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Endometriose/metabolismo , Endométrio/metabolismo , Sumoilação , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Feminino , Humanos , Células Estromais/metabolismo
14.
Indoor Air ; 31(2): 440-453, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32979003

RESUMO

This study comprehensively investigated the impact of indoor carbon dioxide (CO2 ) concentration on sleep quality. Three experimental conditions (800, 1900, 3000 ppm) were created in chambers decorated as bedroom and other environmental parameters that may influence the sleep quality were under strict control. Sleep quality of 12 subjects (6 men and 6 women) was monitored for 54 consecutive days through sleep quality questionnaire and physiological measures. Both subjective and physiological results showed that sleep quality decreased significantly with the increase of CO2 concentration, and the comprehensive questionnaire score at 3000 ppm was only 80.8% of that at 800 ppm. A linear positive correlation was found between sleep onset latency (SOL) and CO2 concentration, while a linear negative correlation occurred between slow-wave sleep (SWS) and CO2 concentration. In addition, in the same sleep environment, men had higher subjective questionnaire scores after wake-up, longer SWS and shorter SOL, which lead to a better sleep quality compared with women, and there was a significant gender difference in sleep quality at 800 ppm (P < .05).


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Dióxido de Carbono/análise , Sono/fisiologia , Adulto , Feminino , Humanos , Masculino
15.
J Environ Manage ; 279: 111583, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33187783

RESUMO

Greenhouse gasses (GHG) emission from the agricultural lands is a serious threat to the environment. Plants such as rice (Oryza sativa L.) that are cultivated in submerged conditions (paddy field) contribute up to 19% of CH4 emission from agricultural lands. Such plants have evolved lysigenous aerenchyma in their root system which facilitates the exchange of O2 and GHG between aerial parts of plant and rhizosphere. Currently, the regulation of GHG and O2 via aerenchyma formation is poorly understood in plants, especially in rice. Here, a reverse genetic approach was employed to reduce the aerenchyma formation by analyzing two mutants i.e., oslsd1.1-m12 and oslsd1.1-m51 generated by Tos17 and T-DNA insertion. The wild-type (WT) and the mutants were grown in paddy (flooded), non-paddy and hydroponic system to assess phenotypic traits including O2 diffusion, GHG emission and aerenchyma formation. The mutants exhibited significant reductions in several morphophysiological traits including 20-60% aerenchyma formation at various distances from the root apex, 25% root development, 50% diffusion of O2 and 27-36% emission of methane (CH4) as compared to WT. The differential effects of the oslsd1.1 mutants in aerenchyma-mediated CH4 mitigation were also evident in the diversity of (pmoA, mcrA) methanotrophs in the rhizosphere. Our results indicate the novel pathway in which reduced aerenchyma in rice is responsible for the mitigation of CH4, diffusion of O2 and the root growth in rice. Limited aerenchyma mediated approach to mitigate GHG specially CH4 mitigation in agriculture is helpful technique for sustainable development.


Assuntos
Gases de Efeito Estufa , Oryza , Agricultura , Metano/análise , Oxigênio , Solo
16.
BMC Genomics ; 21(1): 245, 2020 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-32188400

RESUMO

BACKGROUND: Sheath blight (SB), caused by Rhizoctonia solani, is a common rice disease worldwide. Currently, rice cultivars with robust resistance to R. solani are still lacking. To provide theoretic basis for molecular breeding of R. solani-resistant rice cultivars, the changes of transcriptome profiles in response to R. solani infection were compared between a moderate resistant cultivar (Yanhui-888, YH) and a susceptible cultivar (Jingang-30, JG). RESULTS: In the present study, 3085 differentially express genes (DEGs) were detected between the infected leaves and the control in JG, with 2853 DEGs in YH. A total of 4091 unigenes were significantly upregulated in YH than in JG before infection, while 3192 were significantly upregulated after infection. Further analysis revealed that YH and JG showed similar molecular responses to R. solani infection, but the responses were earlier in JG than in YH. Expression levels of trans-cinnamate 4-monooxygenase (C4H), ethylene-insensitive protein 2 (EIN2), transcriptome factor WRKY33 and the KEGG pathway plant-pathogen interaction were significantly affected by R. solani infection. More importantly, these components were all over-represented in YH cultivar than in JG cultivar before and/or after infection. CONCLUSIONS: These genes possibly contribute to the higher resistance of YH to R. solani than JG and were potential target genes to molecularly breed R. solani-resistant rice cultivar.


Assuntos
Oryza/genética , Oryza/microbiologia , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Folhas de Planta/genética , Folhas de Planta/microbiologia , Rhizoctonia , Transcriptoma/genética , Resistência à Doença/genética , Regulação da Expressão Gênica de Plantas
17.
Hum Mol Genet ; 25(6): 1215-24, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26744325

RESUMO

Epidemiological studies suggest that levels of n-3 and n-6 long-chain polyunsaturated fatty acids are associated with risk of cardio-metabolic outcomes across different ethnic groups. Recent genome-wide association studies in populations of European ancestry have identified several loci associated with plasma and/or erythrocyte polyunsaturated fatty acids. To identify additional novel loci, we carried out a genome-wide association study in two population-based cohorts consisting of 3521 Chinese participants, followed by a trans-ethnic meta-analysis with meta-analysis results from 8962 participants of European ancestry. Four novel loci (MYB, AGPAT4, DGAT2 and PPT2) reached genome-wide significance in the trans-ethnic meta-analysis (log10(Bayes Factor) ≥ 6). Of them, associations of MYB and AGPAT4 with docosatetraenoic acid (log10(Bayes Factor) = 11.5 and 8.69, respectively) also reached genome-wide significance in the Chinese-specific genome-wide association analyses (P = 4.15 × 10(-14) and 4.30 × 10(-12), respectively), while associations of DGAT2 with gamma-linolenic acid (log10(Bayes Factor) = 6.16) and of PPT2 with docosapentaenoic acid (log10(Bayes Factor) = 6.24) were nominally significant in both Chinese- and European-specific genome-wide association analyses (P ≤ 0.003). We also confirmed previously reported loci including FADS1, NTAN1, NRBF2, ELOVL2 and GCKR. Different effect sizes in FADS1 and independent association signals in ELOVL2 were observed. These results provide novel insight into the genetic background of polyunsaturated fatty acids and their differences between Chinese and European populations.


Assuntos
Ácidos Graxos Insaturados/genética , População Branca/genética , Povo Asiático/genética , Teorema de Bayes , Dessaturase de Ácido Graxo Delta-5 , Ácidos Graxos Insaturados/sangue , Feminino , Loci Gênicos , Estudo de Associação Genômica Ampla , Humanos , Masculino , Polimorfismo de Nucleotídeo Único , Fatores de Risco
18.
Phys Chem Chem Phys ; 20(23): 15687-15695, 2018 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-29846373

RESUMO

More than ten years ago, Manners and coworkers published the first experimental study on the efficiency of titanocene to catalyze the dehydrocoupling of dimethylamine borane (DMAB, T. Clark, C. Russell and I. Manners, J. Am. Chem. Soc., 2006, 128, 9582-9583). Several experimental investigations have shown that a two-step mechanism leads to the formation of a cyclic diborazane (Me2N-BH2)2via the linear diborazane (HNMe2-BH2-NMe2-BH3). This finding stood in contradiction to the following theoretical investigations of the reaction pathway. Herein, using dispersion-corrected density functional theory (DFT-D), we propose an energetically favored reaction mechanism in perfect agreement with the experimental findings. It is shown that van der Waals interactions play a prominent role in the reaction pathway. The formation of 3-center 2-electron interactions, classical dihydrogen bonds, and non-classical dihydrogen bonds was identified with the help of topological and localized orbital approaches.

19.
J Lipid Res ; 58(5): 974-981, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28298293

RESUMO

MUFAs are unsaturated FAs with one double bond and are derived from endogenous synthesis and dietary intake. Accumulating evidence has suggested that plasma and erythrocyte MUFA levels are associated with cardiometabolic disorders, including CVD, T2D, and metabolic syndrome (MS). Previous genome-wide association studies (GWASs) have identified seven loci for plasma and erythrocyte palmitoleic and oleic acid levels in populations of European origin. To identify additional MUFA-associated loci and the potential functional variant at each locus, we performed ethnic-specific GWAS meta-analyses and trans-ethnic meta-analyses in more than 15,000 participants of Chinese and European ancestry. We identified novel genome-wide significant associations for vaccenic acid at FADS1/2 and PKD2L1 [log10(Bayes factor) ≥ 8.07] and for gondoic acid at FADS1/2 and GCKR [log10(Bayes factor) ≥ 6.22], and also observed improved fine-mapping resolutions at FADS1/2 and GCKR loci. The greatest improvement was observed at GCKR, where the number of variants in the 99% credible set was reduced from 16 (covering 94.8 kb) to 5 (covering 19.6 kb, including a missense variant rs1260326) after trans-ethnic meta-analysis. We also confirmed the previously reported associations of PKD2L1, FADS1/2, GCKR, and HIF1AN with palmitoleic acid and of FADS1/2 and LPCAT3 with oleic acid in the Chinese-specific GWAS and the trans-ethnic meta-analyses. Pathway-based analyses suggested that the identified loci were in unsaturated FA metabolism and signaling pathways. Our findings provide novel insight into the genetic basis relevant to MUFA metabolism and biology.


Assuntos
Povo Asiático/genética , Mapeamento Cromossômico/métodos , Ácidos Graxos Monoinsaturados/metabolismo , Loci Gênicos/genética , População Branca/genética , Dessaturase de Ácido Graxo Delta-5 , Estudo de Associação Genômica Ampla , Humanos
20.
Hum Mol Genet ; 24(3): 865-74, 2015 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-25249183

RESUMO

Hypertension is a common disorder and the leading risk factor for cardiovascular disease and premature deaths worldwide. Genome-wide association studies (GWASs) in the European population have identified multiple chromosomal regions associated with blood pressure, and the identified loci altogether explain only a small fraction of the variance for blood pressure. The differences in environmental exposures and genetic background between Chinese and European populations might suggest potential different pathways of blood pressure regulation. To identify novel genetic variants affecting blood pressure variation, we conducted a meta-analysis of GWASs of blood pressure and hypertension in 11 816 subjects followed by replication studies including 69 146 additional individuals. We identified genome-wide significant (P < 5.0 × 10(-8)) associations with blood pressure, which included variants at three new loci (CACNA1D, CYP21A2, and MED13L) and a newly discovered variant near SLC4A7. We also replicated 14 previously reported loci, 8 (CASZ1, MOV10, FGF5, CYP17A1, SOX6, ATP2B1, ALDH2, and JAG1) at genome-wide significance, and 6 (FIGN, ULK4, GUCY1A3, HFE, TBX3-TBX5, and TBX3) at a suggestive level of P = 1.81 × 10(-3) to 5.16 × 10(-8). These findings provide new mechanistic insights into the regulation of blood pressure and potential targets for treatments.


Assuntos
Povo Asiático/genética , Pressão Sanguínea/genética , Canais de Cálcio Tipo L/genética , Hipertensão/genética , Complexo Mediador/genética , Simportadores de Sódio-Bicarbonato/genética , Esteroide 21-Hidroxilase/genética , Adulto , Idoso , China , Feminino , Loci Gênicos , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único
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