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1.
Sci Rep ; 13(1): 5672, 2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-37024550

RESUMO

It is debatable whether external forcing can change the state of the climate. By investigating decadal changes with and without including the 1990s stratospheric volcanic aerosols, we explored the volcanic eruptions contribution to decadal climate regime shifts occurring in boreal winter over the North Pacific. The volcanic eruptions contribution can be characterized as a series of rapid changes, including the strengthening and poleward shift of the midlatitude westerly jet stream. In addition to the short-lived radiative effects primarily induced by the 1991 Mount Pinatubo eruption, the volcanically driven decadal change can be observed in the mid-to-late 1990s, suggesting a time-lagged characteristic of the volcanic climate impact. Compared with the decadal change irrelevant to volcanic eruption, the decadal state more dramatically enters into the next phase when volcanic forcing is included. The climate oscillation-related pattern shifts that occurred across the 1990s can provide insights into volcanically induced changes in decadal atmospheric circulation.

2.
J Asian Econ ; 83: 101544, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36124127

RESUMO

In 2020, governments worldwide enforced lockdowns to contain the spread of COVID-19, severely impeding aspects of daily life such as work, school, and tourism. Consequently, numerous economic activities were affected. Before the COVID-19 outbreak, city-center housing markets in areas surrounding popular tourist attractions performed better than did suburban housing markets because of the output of the tourism industry. This study examines the changes in the performance of city-center and suburban housing markets in regions with popular tourist attractions after the lockdown. Specifically, the dynamics of city-center and suburban housing markets in Hangzhou, where West Lake is located, and the changes in the information transfer between these housing markets after the lockdown are explored. Transaction data from January 1, 2019 to September 30, 2020 are used to perform analysis, in which adjusted housing prices and asking prices are employed to measure market performance and sellers' pricing strategies, and transaction volume and time on the market are used to measure market liquidity and transaction frequency. The results reveal that the effects of lockdowns differ between city-center and suburban housing markets. After the lockdown, a substantial structural change is observed in the suburban housing market; the volatility risk of housing prices decreases substantially, causing an increase in transaction premiums. Housing prices and transaction volume increase in the city-center housing market after the lockdown; this is possibly because of the influence from the overall housing market booms. In addition, because sellers raise their asking prices and the transaction time is extended, the sellers in the city-center housing market are particularly influenced by the disposition effect. This leads to a reversal in the lead-lag relationship between the city center and suburban housing markets in terms of informativeness. Specifically, before the lockdown, the city-center market transfers information to the suburban market, but after the lockdown, the suburban market transfers information to the city-center market. The COVID-19 pandemic has changed the world in many aspects; this paper finds that it will also change the development pattern of the real estate market in different locations.

3.
Artigo em Inglês | MEDLINE | ID: mdl-35805822

RESUMO

Increasing surface air temperature is a fundamental characteristic of a warming world. Rising temperatures have potential impacts on human health through heat stress. One heat stress metric is the wet-bulb globe temperature, which takes into consideration the effects of radiation, humidity, and wind speed. It also has broad health and environmental implications. This study presents wet-bulb globe temperatures calculated from the fifth-generation European Centre for Medium-Range Weather Forecasts atmospheric reanalysis and combines it with health guidelines to assess heat stress variability and the potential for reduction in labor hours over the past decade on both the continental and urban scale. Compared to 2010-2014, there was a general increase in heat stress during the period from 2015 to 2019 throughout the northern hemisphere, with the largest warming found in tropical regions, especially in the northern part of the Indian Peninsula. On the urban scale, our results suggest that heat stress might have led to a reduction in labor hours by up to ~20% in some Asian cities subject to work-rest regulations. Extremes in heat stress can be explained by changes in radiation and circulation. The resultant threat is highest in developing countries in tropical areas where workers often have limited legal protection and healthcare. The effect of heat stress exposure is therefore a collective challenge with environmental, economic, and social implications.


Assuntos
Parto Obstétrico , Feminino , Resposta ao Choque Térmico , Humanos , Gravidez , Estações do Ano , Fatores de Tempo , Saúde da População Urbana , População Urbana
4.
Sci Total Environ ; 846: 157437, 2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-35863568

RESUMO

Ozone is a primary air pollutant that impairs photosynthesis and reduces crop yields, an effect that received little attention in Taiwan, especially under the context of climate warming. This study predicted the impact of surface O3 on cash crop yields, specifically in wheat, potatoes, and tomatoes, under 2 °C and 4 °C climate warming scenarios in Taiwan via high-resolution simulations. The simulated O3 concentration (daytime mean) over Taiwan's croplands during the growing seasons was around 35-52 ppb, and it increased by 0.9 and 2.1 ppb under 2 °C and 4 °C warming for wheat and potatoes. In contrast, more minor changes of around 0.4 ppb were found for tomatoes. The O3 concentrations were converted to AOT40 (Accumulated Ozone exposure over a threshold of 40 ppb) and POD3 (Phytotoxic Ozone Dose above a threshold of 3 nmol O3 m-2) metrics to estimate changes in relative yield (RY). The mean RYPOD3 (RYAOT40) reductions over irrigated cropland for wheat, tomatoes, and potatoes under current climate and O3-stress conditions are 27.5 % (19.1 %), 14.7 % (3.8 %), and 8.2 % (1.6 %), respectively. Under 2 °C warming, the additional reductions would be 2.7 % (1.8 %) for wheat, 4.1 % (0.3 %) for tomatoes, and 2.4 % (0.4 %) for potatoes; the values under 4 °C warming become 4.7 % (4.1 %) for wheat, 8.1 % (0.6 %) for tomatoes, and 5.2 % (0.8 %) for potatoes. The contribution of RYPOD3 reduction was separated into O3-induced and climate-induced effects. The former dominated the additional yield reduction under a 2 °C warming climate, yet, the latter prevailed under 4 °C warming. Further analysis indicated that the temperature rise enhances ozone uptake flux; still, the amplified water vapor deficit and more incoming solar radiation can offset it and weakens the overall meteorological effect, especially from 2 °C to 4 °C warming conditions. Such effects demonstrated a nonlinear effect related to the co-dependence of the ozone uptake flux, which requires attention in agriculture policymaking.


Assuntos
Poluentes Atmosféricos , Ozônio , Agricultura , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Ozônio/análise , Folhas de Planta/química , Estações do Ano , Taiwan , Triticum
5.
J Behav Exp Finance ; 35: 100698, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35755575

RESUMO

This paper explores changes in social behavior since the start of the COVID-19 pandemic, which are characterized by reduction in relocation, mobility, and community engagement, and how the correlations between regional housing markets are affected by these changes. Because changes in mobility and engagement are the most apparent in large cities, the present study calculates the independence indicator of regional housing markets in the 50 largest metropolitan statistical areas (MSAs) in the United States and determines their relationship with Mobility and Engagement Index values. The empirical results show that as mobility and community engagement decline in a certain area, housing market fluctuations become more independent, indicating correlations between regional housing markets in the US might decrease after the COVID-19 outbreak. This paper also finds that there are more MSAs having significantly decreased in volatility since the outbreak of the pandemic. This paper provides evidence indicating that housing markets may be impacted differently by the COVID-19 pandemic than other asset markets, particularly stock markets. Changes in mobility and engagement can be used as an indicator to assess whether the correlation between regional housing markets would decline, which means that, compared with financial instruments, more factors from real aspects need to be considered when determining the changes in real estate affected by the epidemic.

6.
Sci Total Environ ; 782: 146571, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-33838380

RESUMO

In recent years, many surveillance cameras have been installed in the Greater Taipei Area, Taiwan; traffic data obtained from these surveillance cameras could be useful for the development of roadway-based emissions inventories. In this study, web-based traffic information covering the Greater Taipei Area was obtained using a vision-based traffic analysis system. Web-based traffic data were normalized and applied to the Community Multiscale Air Quality (CMAQ) model to study the impact of vehicle emissions on air quality in the Greater Taipei Area. According to an analysis of the obtained traffic data, sedans were the most common vehicles in the Greater Taipei Area, followed by motorcycles. Moderate traffic conditions with an average speed of 30-50 km/h were most prominent during weekdays, whereas traffic flow with an average speed of 50-70 km/h was most common during weekends. The proportion of traffic flows in free-flow conditions (>70 km/h) was higher on weekends than on weekdays. Two peaks of traffic flow were observed during the morning and afternoon peak hours on weekdays. On the weekends, this morning peak was not observed, and the variation in vehicle numbers was lower than on weekdays. The simulation results suggested that the addition of real-time traffic data improved the CMAQ model's performance, especially for the carbon monoxide (CO) and fine particulate matter (PM2.5) concentrations. According to sensitivity tests for total and vehicle emissions in the Greater Taipei Area, vehicle emissions contributed to >90% of CO, 80% of nitrogen oxides (NOx), and approximately 50% of PM2.5 in the downtown areas of Taipei. The vehicle emissions contribution was affected by both vehicle emissions and meteorological conditions. The connection between the surveillance camera data, vehicle emissions, and regional air quality models in this study can also be used to explore the impact of special events (e.g., long weekends and COVID-19 lockdowns) on air quality.

7.
JCI Insight ; 4(22)2019 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-31723061

RESUMO

The ciliopathies are a group of phenotypically overlapping disorders caused by structural or functional defects in the primary cilium. Although disruption of numerous signaling pathways and cellular trafficking events have been implicated in ciliary pathology, treatment options for affected individuals remain limited. Here, we performed a genome-wide RNAi (RNA interference) screen to identify genetic suppressors of BBS4, one of the genes mutated in Bardet-Biedl syndrome (BBS). We discovered 10 genes that, when silenced, ameliorate BBS4-dependent pathology. One of these encodes USP35, a negative regulator of the ubiquitin proteasome system, suggesting that inhibition of a deubiquitinase, and subsequent facilitation of the clearance of signaling components, might ameliorate BBS-relevant phenotypes. Testing of this hypothesis in transient and stable zebrafish genetic models showed this posit to be true; suppression or ablation of usp35 ameliorated hallmark ciliopathy defects including impaired convergent extension (CE), renal tubule convolution, and retinal degeneration with concomitant clearance of effectors such as ß-catenin and rhodopsin. Together, our findings reinforce a direct link between proteasome-dependent degradation and ciliopathies and suggest that augmentation of this system might offer a rational path to novel therapeutic modalities.


Assuntos
Ciliopatias/genética , Endopeptidases/genética , Proteases Específicas de Ubiquitina/genética , Animais , Síndrome de Bardet-Biedl/tratamento farmacológico , Síndrome de Bardet-Biedl/genética , Sistemas CRISPR-Cas/genética , Linhagem Celular , Cílios/genética , Técnicas Genéticas , Humanos , Proteínas Associadas aos Microtúbulos/genética , Fenótipo , Degeneração Retiniana/genética , Via de Sinalização Wnt/genética , Peixe-Zebra , Proteínas de Peixe-Zebra/genética
8.
Am J Hum Genet ; 104(6): 1233-1240, 2019 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-31130285

RESUMO

Noonan syndrome (NS) is characterized by distinctive craniofacial appearance, short stature, and congenital heart disease. Approximately 80% of individuals with NS harbor mutations in genes whose products are involved in the RAS/mitogen-activating protein kinase (MAPK) pathway. However, the underlying genetic causes in nearly 20% of individuals with NS phenotype remain unexplained. Here, we report four de novo RRAS2 variants in three individuals with NS. RRAS2 is a member of the RAS subfamily and is ubiquitously expressed. Three variants, c.70_78dup (p.Gly24_Gly26dup), c.216A>T (p.Gln72His), and c.215A>T (p.Gln72Leu), have been found in cancers; our functional analyses showed that these three changes induced elevated association of RAF1 and that they activated ERK1/2 and ELK1. Notably, prominent activation of ERK1/2 and ELK1 by p.Gln72Leu associates with the severe phenotype of the individual harboring this change. To examine variant pathogenicity in vivo, we generated zebrafish models. Larvae overexpressing c.70_78dup (p.Gly24_Gly26dup) or c.216A>T (p.Gln72His) variants, but not wild-type RRAS2 RNAs, showed craniofacial defects and macrocephaly. The same dose injection of mRNA encoding c.215A>T (p.Gln72Leu) caused severe developmental impairments and low dose overexpression of this variant induced craniofacial defects. In contrast, the RRAS2 c.224T>G (p.Phe75Cys) change, located on the same allele with p.Gln72His in an individual with NS, resulted in no aberrant in vitro or in vivo phenotypes by itself. Together, our findings suggest that activating RRAS2 mutations can cause NS and expand the involvement of RRAS2 proto-oncogene to rare germline disorders.


Assuntos
Mutação com Ganho de Função , Mutação em Linhagem Germinativa , Proteínas de Membrana/genética , Proteínas Monoméricas de Ligação ao GTP/genética , Síndrome de Noonan/etiologia , Peixe-Zebra/crescimento & desenvolvimento , Sequência de Aminoácidos , Animais , Criança , Pré-Escolar , Exoma , Feminino , Humanos , Masculino , Proteínas de Membrana/química , Proteínas de Membrana/metabolismo , Proteínas Monoméricas de Ligação ao GTP/química , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Síndrome de Noonan/patologia , Fenótipo , Conformação Proteica , Proto-Oncogene Mas , Homologia de Sequência , Peixe-Zebra/genética , Peixe-Zebra/metabolismo
9.
Sci Rep ; 8(1): 10779, 2018 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-30018450

RESUMO

Kabuki Syndrome (KS) is a rare disorder characterized by distinctive facial features, short stature, skeletal abnormalities, and neurodevelopmental deficits. Previously, we showed that loss of function of RAP1A, a RAF1 regulator, can activate the RAS/MAPK pathway and cause KS, an observation recapitulated in other genetic models of the disorder. These data suggested that suppression of this signaling cascade might be of therapeutic benefit for some features of KS. To pursue this possibility, we performed a focused small molecule screen of a series of RAS/MAPK pathway inhibitors, where we tested their ability to rescue disease-relevant phenotypes in a zebrafish model of the most common KS locus, kmt2d. Consistent with a pathway-driven screening paradigm, two of 27 compounds showed reproducible rescue of early developmental pathologies. Further analyses showed that one compound, desmethyl-Dabrafenib (dmDf), induced no overt pathologies in zebrafish embryos but could rescue MEK hyperactivation in vivo and, concomitantly, structural KS-relevant phenotypes in all KS zebrafish models (kmt2d, kmd6a and rap1). Mass spectrometry quantitation suggested that a 100 nM dose resulted in sub-nanomolar exposure of this inhibitor and was sufficient to rescue both mandibular and neurodevelopmental defects. Crucially, germline kmt2d mutants recapitulated the gastrulation movement defects, micrognathia and neurogenesis phenotypes of transient models; treatment with dmDf ameliorated all of them significantly. Taken together, our data reinforce a causal link between MEK hyperactivation and KS and suggest that chemical suppression of BRAF might be of potential clinical utility for some features of this disorder.


Assuntos
Anormalidades Múltiplas/prevenção & controle , Face/anormalidades , Doenças Hematológicas/prevenção & controle , Imidazóis/farmacologia , Oximas/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Doenças Vestibulares/prevenção & controle , Peixe-Zebra/crescimento & desenvolvimento , Anormalidades Múltiplas/patologia , Animais , Anormalidades Craniofaciais/prevenção & controle , Face/patologia , Doenças Hematológicas/patologia , Imidazóis/efeitos adversos , Imidazóis/química , Anormalidades Maxilomandibulares/prevenção & controle , Sistema de Sinalização das MAP Quinases , Oximas/efeitos adversos , Oximas/química , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Testes de Toxicidade , Doenças Vestibulares/patologia , Peixe-Zebra/embriologia , Peixe-Zebra/genética
10.
Hum Genomics ; 12(1): 11, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29490693

RESUMO

BACKGROUND: Intellectual disability (ID) is a common condition with a population prevalence frequency of 1-3% and an enrichment for males, driven in part by the contribution of mutant alleles on the X-chromosome. Among the more than 500 genes associated with ID, DDX3X represents an outlier in sex specificity. Nearly all reported pathogenic variants of DDX3X are de novo, affect mostly females, and appear to be loss of function variants, consistent with the hypothesis that haploinsufficiency at this locus on the X-chromosome is likely to be lethal in males. RESULTS: We evaluated two male siblings with syndromic features characterized by mild-to-moderate ID and progressive spasticity. Quad-based whole-exome sequencing revealed a maternally inherited missense variant encoding p.R79K in DDX3X in both siblings and no other apparent pathogenic variants. We assessed its possible relevance to their phenotype using an established functional assay for DDX3X activity in zebrafish embryos and found that this allele causes a partial loss of DDX3X function and thus represents a hypomorphic variant. CONCLUSIONS: Our genetic and functional data suggest that partial loss of function of DDX3X can cause syndromic ID. The p.R79K allele affects a region of the protein outside the critical RNA helicase domain, offering a credible explanation for the observed retention of partial function, viability in hemizygous males, and lack of pathology in females. These findings expand the gender spectrum of pathology of this locus and suggest that analysis for DDX3X variants should be considered relevant for both males and females.


Assuntos
RNA Helicases DEAD-box/genética , Deficiência Intelectual/genética , Doenças Neurodegenerativas/genética , Transtornos do Neurodesenvolvimento/genética , Adolescente , Adulto , Alelos , Cromossomos Humanos X/genética , Exoma/genética , Feminino , Humanos , Deficiência Intelectual/fisiopatologia , Masculino , Mutação , Doenças Neurodegenerativas/fisiopatologia , Transtornos do Neurodesenvolvimento/fisiopatologia , Linhagem , Sequenciamento do Exoma , Adulto Jovem
11.
Sci Total Environ ; 566-567: 919-928, 2016 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-27285533

RESUMO

The prospective impacts of electric vehicle (EV) penetration on the air quality in Taiwan were evaluated using an air quality model with the assumption of an ambitious replacement of current light-duty vehicles under different power generation scenarios. With full EV penetration (i.e., the replacement of all light-duty vehicles), CO, VOCs, NOx and PM2.5 emissions in Taiwan from a fleet of 20.6 million vehicles would be reduced by 1500, 165, 33.9 and 7.2Ggyr(-1), respectively, while electric sector NOx and SO2 emissions would be increased by up to 20.3 and 12.9Ggyr(-1), respectively, if the electricity to power EVs were provided by thermal power plants. The net impacts of these emission changes would be to reduce the annual mean surface concentrations of CO, VOCs, NOx and PM2.5 by about 260, 11.3, 3.3ppb and 2.1µgm(-3), respectively, but to increase SO2 by 0.1ppb. Larger reductions tend to occur at time and place of higher ambient concentrations and during high pollution events. Greater benefits would clearly be attained if clean energy sources were fully encouraged. EV penetration would also reduce the mean peak-time surface O3 concentrations by up to 7ppb across Taiwan with the exception of the center of metropolitan Taipei where the concentration increased by <2ppb. Furthermore, full EV penetration would reduce annual days of O3 pollution episodes by ~40% and PM2.5 pollution episodes by 6-10%. Our findings offer important insights into the air quality impacts of EV and can provide useful information for potential mitigation actions.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Fontes de Energia Elétrica , Veículos Automotores/classificação , Emissões de Veículos/análise , Eletricidade , Monitoramento Ambiental , Taiwan
12.
J Clin Invest ; 125(9): 3585-99, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26280580

RESUMO

The genetic disorder Kabuki syndrome (KS) is characterized by developmental delay and congenital anomalies. Dominant mutations in the chromatin regulators lysine (K)-specific methyltransferase 2D (KMT2D) (also known as MLL2) and lysine (K)-specific demethylase 6A (KDM6A) underlie the majority of cases. Although the functions of these chromatin-modifying proteins have been studied extensively, the physiological systems regulated by them are largely unknown. Using whole-exome sequencing, we identified a mutation in RAP1A that was converted to homozygosity as the result of uniparental isodisomy (UPD) in a patient with KS and a de novo, dominant mutation in RAP1B in a second individual with a KS-like phenotype. We elucidated a genetic and functional interaction between the respective KS-associated genes and their products in zebrafish models and patient cell lines. Specifically, we determined that dysfunction of known KS genes and the genes identified in this study results in aberrant MEK/ERK signaling as well as disruption of F-actin polymerization and cell intercalation. Moreover, these phenotypes could be rescued in zebrafish models by rebalancing MEK/ERK signaling via administration of small molecule inhibitors of MEK. Taken together, our studies suggest that the KS pathophysiology overlaps with the RASopathies and provide a potential direction for treatment design.


Assuntos
Anormalidades Múltiplas/genética , Exoma , Face/anormalidades , Doenças Hematológicas/genética , Sistema de Sinalização das MAP Quinases/genética , Proteínas Monoméricas de Ligação ao GTP/genética , Mutação , Proteínas de Ligação a Telômeros/genética , Doenças Vestibulares/genética , Proteínas de Peixe-Zebra/genética , Anormalidades Múltiplas/metabolismo , Actinas/genética , Actinas/metabolismo , Animais , Bovinos , Criança , Pré-Escolar , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Modelos Animais de Doenças , Doenças Hematológicas/metabolismo , Histona Desmetilases/genética , Histona Desmetilases/metabolismo , Humanos , Masculino , Camundongos , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Ratos , Complexo Shelterina , Proteínas de Ligação a Telômeros/metabolismo , Doenças Vestibulares/metabolismo , Peixe-Zebra , Proteínas de Peixe-Zebra/metabolismo
13.
Am J Hum Genet ; 94(5): 745-54, 2014 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-24746959

RESUMO

Homozygosity for a recurrent 290 kb deletion of NPHP1 is the most frequent cause of isolated nephronophthisis (NPHP) in humans. A deletion of the same genomic interval has also been detected in individuals with Joubert syndrome (JBTS), and in the mouse, Nphp1 interacts genetically with Ahi1, a known JBTS locus. Given these observations, we investigated the contribution of NPHP1 in Bardet-Biedl syndrome (BBS), a ciliopathy of intermediate severity. By using a combination of array-comparative genomic hybridization, TaqMan copy number assays, and sequencing, we studied 200 families affected by BBS. We report a homozygous NPHP1 deletion CNV in a family with classical BBS that is transmitted with autosomal-recessive inheritance. Further, we identified heterozygous NPHP1 deletions in two more unrelated persons with BBS who bear primary mutations at another BBS locus. In parallel, we identified five families harboring an SNV in NPHP1 resulting in a conserved missense change, c.14G>T (p.Arg5Leu), that is enriched in our Hispanic pedigrees; in each case, affected individuals carried additional bona fide pathogenic alleles in another BBS gene. In vivo functional modeling in zebrafish embryos demonstrated that c.14G>T is a loss-of-function variant, and suppression of nphp1 in concert with each of the primary BBS loci found in our NPHP1-positive pedigrees exacerbated the severity of the phenotype. These results suggest that NPHP1 mutations are probably rare primary causes of BBS that contribute to the mutational burden of the disorder.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Síndrome de Bardet-Biedl/genética , Variações do Número de Cópias de DNA , Proteínas de Membrana/genética , Alelos , Animais , Proteínas do Citoesqueleto , Gastrulação/genética , Loci Gênicos , Heterozigoto , Homozigoto , Humanos , Rim/anormalidades , Camundongos , Linhagem , Deleção de Sequência , Peixe-Zebra/anormalidades , Peixe-Zebra/genética
14.
Biomed Res Int ; 2014: 136130, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24757665

RESUMO

The clinical and biological significance of the study of fungal pathogen Candida albicans (C. albicans) has markedly increased. However, the explicit pathogenic and invasive mechanisms of such host-pathogen interactions have not yet been fully elucidated. Therefore, the essential functional modules involved in C. albicans-zebrafish interactions were investigated in this study. Adopting a systems biology approach, the early-stage and late-stage protein-protein interaction (PPI) networks for both C. albicans and zebrafish were constructed. By comparing PPI networks at the early and late stages of the infection process, several critical functional modules were identified in both pathogenic and defensive mechanisms. Functional modules in C. albicans, like those involved in hyphal morphogenesis, ion and small molecule transport, protein secretion, and shifts in carbon utilization, were seen to play important roles in pathogen invasion and damage caused to host cells. Moreover, the functional modules in zebrafish, such as those involved in immune response, apoptosis mechanisms, ion transport, protein secretion, and hemostasis-related processes, were found to be significant as defensive mechanisms during C. albicans infection. The essential functional modules thus determined could provide insights into the molecular mechanisms of host-pathogen interactions during the infection process and thereby devise potential therapeutic strategies to treat C. albicans infection.


Assuntos
Candida albicans/imunologia , Candidíase/imunologia , Candidíase/microbiologia , Interações Hospedeiro-Patógeno/imunologia , Imunidade Inata/imunologia , Peixe-Zebra/imunologia , Peixe-Zebra/microbiologia , Animais , Proteínas de Bactérias/imunologia , Candida albicans/patogenicidade , Transdução de Sinais/imunologia
15.
J Clin Invest ; 124(5): 2059-70, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24691443

RESUMO

Cilia are critical mediators of paracrine signaling; however, it is unknown whether proteins that contribute to ciliopathies converge on multiple paracrine pathways through a common mechanism. Here, we show that loss of cilopathy-associated proteins Bardet-Biedl syndrome 4 (BBS4) or oral-facial-digital syndrome 1 (OFD1) results in the accumulation of signaling mediators normally targeted for proteasomal degradation. In WT cells, several BBS proteins and OFD1 interacted with proteasomal subunits, and loss of either BBS4 or OFD1 led to depletion of multiple subunits from the centrosomal proteasome. Furthermore, overexpression of proteasomal regulatory components or treatment with proteasomal activators sulforaphane (SFN) and mevalonolactone (MVA) ameliorated signaling defects in cells lacking BBS1, BBS4, and OFD1, in morphant zebrafish embryos, and in induced neurons from Ofd1-deficient mice. Finally, we tested the hypothesis that other proteasome-dependent pathways not known to be associated with ciliopathies are defective in the absence of ciliopathy proteins. We found that loss of BBS1, BBS4, or OFD1 led to decreased NF-κB activity and concomitant IκBß accumulation and that these defects were ameliorated with SFN treatment. Taken together, our data indicate that basal body proteasomal regulation governs paracrine signaling pathways and suggest that augmenting proteasomal function might benefit ciliopathy patients.


Assuntos
Proteínas I-kappa B/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas/metabolismo , Proteólise , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/metabolismo , Animais , Anticarcinógenos/farmacologia , Linhagem Celular , Transtornos da Motilidade Ciliar/tratamento farmacológico , Transtornos da Motilidade Ciliar/genética , Transtornos da Motilidade Ciliar/metabolismo , Transtornos da Motilidade Ciliar/patologia , Humanos , Proteínas I-kappa B/genética , Isotiocianatos/farmacologia , Ácido Mevalônico/análogos & derivados , Ácido Mevalônico/farmacologia , Camundongos , Proteínas Associadas aos Microtúbulos/genética , Proteínas/genética , Sulfóxidos , Proteínas de Peixe-Zebra/genética
16.
Hum Mol Genet ; 23(13): 3607-17, 2014 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-24556213

RESUMO

Loss-of-function mutations in PAK3 contribute to non-syndromic X-linked intellectual disability (NS-XLID) by affecting dendritic spine density and morphology. Linkage analysis in a three-generation family with affected males showing ID, agenesis of corpus callosum, cerebellar hypoplasia, microcephaly and ichthyosis, revealed a candidate disease locus in Xq21.33q24 encompassing over 280 genes. Subsequent to sequencing all coding exons of the X chromosome, we identified a single novel variant within the linkage region, affecting a conserved codon of PAK3. Biochemical studies showed that, similar to previous NS-XLID-associated lesions, the predicted amino acid substitution (Lys389Asn) abolished the kinase activity of PAK3. In addition, the introduced residue conferred a dominant-negative function to the protein that drives the syndromic phenotype. Using a combination of in vitro and in vivo studies in zebrafish embryos, we show that PAK3(N389) escapes its physiologic degradation and is able to perturb MAPK signaling via an uncontrolled kinase-independent function, which in turn leads to alterations of cerebral and craniofacial structures in vivo. Our data expand the spectrum of phenotypes associated with PAK3 mutations, characterize a novel mechanism resulting in a dual molecular effect of the same mutation with a complex PAK3 functional deregulation and provide evidence for a direct functional impact of aberrant PAK3 function on MAPK signaling.


Assuntos
Proteínas Quinases Ativadas por Mitógeno/metabolismo , Quinases Ativadas por p21/genética , Proteínas ras/metabolismo , Animais , Éxons/genética , Humanos , Cariotipagem , Proteínas Quinases Ativadas por Mitógeno/genética , Mutação , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Proteínas ras/genética
17.
J Vis Exp ; (78): e50338, 2013 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-23995499

RESUMO

Here, we present methods for the development of assays to query potentially clinically significant nonsynonymous changes using in vivo complementation in zebrafish. Zebrafish (Danio rerio) are a useful animal system due to their experimental tractability; embryos are transparent to enable facile viewing, undergo rapid development ex vivo, and can be genetically manipulated. These aspects have allowed for significant advances in the analysis of embryogenesis, molecular processes, and morphogenetic signaling. Taken together, the advantages of this vertebrate model make zebrafish highly amenable to modeling the developmental defects in pediatric disease, and in some cases, adult-onset disorders. Because the zebrafish genome is highly conserved with that of humans (~70% orthologous), it is possible to recapitulate human disease states in zebrafish. This is accomplished either through the injection of mutant human mRNA to induce dominant negative or gain of function alleles, or utilization of morpholino (MO) antisense oligonucleotides to suppress genes to mimic loss of function variants. Through complementation of MO-induced phenotypes with capped human mRNA, our approach enables the interpretation of the deleterious effect of mutations on human protein sequence based on the ability of mutant mRNA to rescue a measurable, physiologically relevant phenotype. Modeling of the human disease alleles occurs through microinjection of zebrafish embryos with MO and/or human mRNA at the 1-4 cell stage, and phenotyping up to seven days post fertilization (dpf). This general strategy can be extended to a wide range of disease phenotypes, as demonstrated in the following protocol. We present our established models for morphogenetic signaling, craniofacial, cardiac, vascular integrity, renal function, and skeletal muscle disorder phenotypes, as well as others.


Assuntos
Doença/genética , Genoma Humano , Genômica/métodos , Modelos Animais , Peixe-Zebra/genética , Animais , Humanos , Microinjeções , Morfolinos/administração & dosagem , Morfolinos/genética , Oligonucleotídeos Antissenso/administração & dosagem , Oligonucleotídeos Antissenso/genética , RNA Mensageiro/administração & dosagem , RNA Mensageiro/genética
18.
Nat Med ; 18(9): 1423-8, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22941275

RESUMO

Cilia are evolutionarily conserved microtubule-based organelles that are crucial for diverse biological functions, including motility, cell signaling and sensory perception. In humans, alterations in the formation and function of cilia manifest clinically as ciliopathies, a growing class of pleiotropic genetic disorders. Despite the substantial progress that has been made in identifying genes that cause ciliopathies, therapies for these disorders are not yet available to patients. Although mice with a hypomorphic mutation in the intraflagellar transport protein IFT88 (Ift88Tg737Rpw mice, also known as ORPK mice)5 have been well studied, the relevance of IFT88 mutations to human pathology is unknown. We show that a mutation in IFT88 causes a hitherto unknown human ciliopathy. In vivo complementation assays in zebrafish and mIMCD3 cells show the pathogenicity of this newly discovered allele. We further show that ORPK mice are functionally anosmic as a result of the loss of cilia on their olfactory sensory neurons (OSNs). Notably, adenoviral-mediated expression of IFT88 in mature, fully differentiated OSNs of ORPK mice is sufficient to restore ciliary structures and rescue olfactory function. These studies are the first to use in vivo therapeutic treatment to reestablish cilia in a mammalian ciliopathy. More broadly, our studies indicate that gene therapy is a viable option for cellular and functional rescue of the complex ciliary organelle in established differentiated cells.


Assuntos
Cílios/genética , Cílios/patologia , Doenças Genéticas Inatas/genética , Terapia Genética/métodos , Neurônios Receptores Olfatórios/citologia , Olfato/fisiologia , Proteínas Supressoras de Tumor/genética , Adenoviridae , Animais , Teste de Complementação Genética , Doenças Genéticas Inatas/patologia , Doenças Genéticas Inatas/terapia , Vetores Genéticos , Humanos , Camundongos , Microscopia de Fluorescência , Mutação/genética , Neurônios Receptores Olfatórios/metabolismo , Olfato/genética , Tubulina (Proteína)/metabolismo , Peixe-Zebra
19.
Plant Physiol Biochem ; 56: 1-13, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22579939

RESUMO

A cDNA fragment (FaPR4) encoding a class I pathogenesis-related protein 4 (PR-4) from Ficus awkeotsang was obtained by PCR cloning. Plant PR-4s were grouped into class I and II, differing by the presence of ChtBD and hinge. The predicted mature FaPR4 comprises N-terminal chitin-binding domain (ChtBD), hinge, Barwin domain and C-terminal extension. FaPR4-C, an N-terminal truncated form of FaPR4, was designed to mimic the structural feature of class II PR-4s. FaPR4 and FaPR4-C were over-expressed in yeast Pichia pastoris, and both recombinants exhibited RNase and anti-fungal activities. To our knowledge, it is the first report that FaPR4, a member of class I PR-4s has RNase activity as class II. FaPR4 possesses better anti-fungal activities toward Fusarium oxysporum and Sclerotium rolfsii than FaPR4-C. Heat-treated FaPR4 remained RNase and anti-fungal activities; while heat-treated FaPR4-C lost those activities. Therefore, ChtBD of FaPR4 may not only contribute to its anti-fungal but also improve the thermal stability of protein. It also implied the correlation of RNase activity with anti-fungal activity of FaPR4-C. Furthermore, FaPR4 was detected to have weak but significant chitinase activity, and its chitinase activity was reduced after heat treatment. The chitinase activity by FaPR4-C was much lower than FaPR4.


Assuntos
Antifúngicos/farmacologia , Quitina/metabolismo , Ficus/química , Fungos/efeitos dos fármacos , Expressão Gênica , Proteínas de Plantas/farmacologia , Ribonucleases/farmacologia , Sequência de Aminoácidos , Antifúngicos/metabolismo , Quitinases/metabolismo , Clonagem Molecular , DNA Complementar , Fusarium/efeitos dos fármacos , Temperatura Alta , Dados de Sequência Molecular , Pichia/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , RNA/metabolismo , Ribonucleases/genética , Ribonucleases/metabolismo , Sementes/química
20.
Naunyn Schmiedebergs Arch Pharmacol ; 381(6): 495-505, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20349046

RESUMO

The established antiplatelet and anticoagulant agents show beneficial effects in the treatment of thromboembolic diseases; however, these drugs still have considerable limitations. The effects of NP-184, a synthetic compound, on platelet functions, plasma coagulant activity, and mesenteric venule thrombosis in mice were investigated. NP-184 concentration-dependently inhibited the human platelet aggregation induced by collagen, arachidonic acid (AA), and U46619, a thromboxane (TX)A(2) mimic, with IC(50) values of 4.5 +/- 0.2, 3.9 +/- 0.1, and 9.3 +/- 0.5 microM, respectively. Moreover, NP-184 concentration-dependently suppressed TXA(2) formations caused by collagen and AA. In exploring effects of NP-184 on enzymes involved in TXA(2) synthesis, we found that NP-184 selectively inhibited TXA(2) synthase activity with an IC(50) value of 4.3 +/- 0.2 microM. Furthermore, NP-184 produced a right shift of the concentration-response curve of U46619, indicating a competitive antagonism on TXA(2)/prostaglandin H(2) receptor. Intriguingly, NP-184 also caused a concentration-dependent prolongation of the activated partial thromboplastin time (aPTT) with no changes in the prothrombin and thrombin time, indicating that it selectively impairs the intrinsic coagulation pathway. Oral administration of NP-184 significantly inhibited thrombus formation of the irradiated mesenteric venules in fluorescein sodium-treated mice without affecting the bleeding time induced by tail transection. However, after oral administration, NP-184 inhibited the ex vivo mouse platelet aggregation triggered by collagen and U46619 and also prolonged aPTT. Taken together, the dual antiplatelet and anticoagulant activities of NP-184 may have therapeutic potential as an oral antithrombotic agent in the treatment of thromboembolic disorders.


Assuntos
Benzimidazóis/farmacologia , Fibrinolíticos/farmacologia , Administração Oral , Animais , Anticoagulantes/administração & dosagem , Anticoagulantes/farmacologia , Benzimidazóis/administração & dosagem , Coagulação Sanguínea/efeitos dos fármacos , Relação Dose-Resposta a Droga , Fibrinolíticos/administração & dosagem , Humanos , Concentração Inibidora 50 , Masculino , Camundongos , Camundongos Endogâmicos ICR , Agregação Plaquetária/efeitos dos fármacos , Inibidores da Agregação Plaquetária/administração & dosagem , Inibidores da Agregação Plaquetária/farmacologia , Trombose Venosa/tratamento farmacológico
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