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1.
Ecotoxicol Environ Saf ; 208: 111582, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396105

RESUMO

In recent years, heavy metal pollution has caused immeasurable harm to the environment. As an emerging technology, phytoremediation technology has gained a place in the treatment of heavy metal pollution with its unique advantages. This study analyzes the toxic effects of mulberry (Morus alba) seeds, seedling growth and silkworm under heavy metal stress of lead (Pb) and cadmium (Cd), and explore the accumulation and migration of Pb and Cd in the soil-mulberry tree-silkworm system. The main results were as follows: (1) Seed germination and potted seedling experiments were conducted under heavy metal Pb and Cd stresses, and it was found that Pb and Cd had inhibitory effects on mulberry seed germination, growth and photosynthesis of mulberry seedlings, and as the concentration of heavy metals increased, the stronger the inhibitory effect. Moreover, Pb and Cd have a synergistic effect under compound stress. (2) The accumulation and transfer rules of Pb and Cd ions in mulberry were different. The content of Pb in mulberry was root > leaf > stem and the content of Cd was root > stem > leaf. The combined stress promoted the transfer of Pb and Cd from the underground part to the aerial portion of mulberry. (3) The silkworm feeds on mulberry leaves contaminated with heavy metals in this experiment and found that: with the increase of silkworm feeding, the heavy metal content in the silkworm body increased significantly, but the content remained in the silkworm body was less, most of it was excreted with silkworm excrement. Combined stress has no significant effect on the detoxification mechanism of silkworm. It is indispensable to think of the synergistic effect of heavy metals on plants germination when seeds are used for phytoremediation.


Assuntos
Bombyx/fisiologia , Cádmio/toxicidade , Cadeia Alimentar , Chumbo/toxicidade , Morus/fisiologia , Poluentes do Solo/toxicidade , Solo/química , Animais , Biodegradação Ambiental , Cádmio/análise , Cádmio/metabolismo , Frutas/química , Metais Pesados/análise , Fotossíntese , Folhas de Planta/química , Plântula/química , Poluentes do Solo/análise , Poluentes do Solo/metabolismo
2.
Artigo em Inglês | MEDLINE | ID: mdl-32028713

RESUMO

China has initiated a tree planting program in epidemic regions of schistosomiasis as a part of efforts to eliminate schistosomiasis. More than 518,900 ha of tree plantations have been planted through the program between 2006 and 2015. However, whether the planting program has fulfilled its mission or not is an open question. In this study, we intended to get the answer from the main stakeholders of the planting program through a large-scale survey. Based on interviews with 80 administrators of the planting program and 1440 farmers in 24 counties and districts in four provinces, we found that most stakeholders viewed the planting program positively. Nearly 92% of farmers and all administrators believed that the planting program had reduced snail densities, while 94.3% of farmers and all administrators believed that the program had lowered the incidences of schistosomiasis. In addition, they reported that the impacts on farmers' living and local environments by the tree planting program were mainly positive. Based on the stakeholders' responses, we conclude that the tree planting program has been perceived by the main stakeholders as an effective environmental control measure of schistosomiasis. However, certain places and people that may be impacted negatively by the program should be given more attention when implementing the program.


Assuntos
Fazendeiros , Programas Governamentais , Esquistossomose , Árvores , Animais , China/epidemiologia , Fazendeiros/estatística & dados numéricos , Feminino , Programas Governamentais/normas , Humanos , Masculino , Percepção , Densidade Demográfica , Prevalência , Esquistossomose/epidemiologia , Esquistossomose/prevenção & controle , Caramujos/parasitologia
3.
Biomed Pharmacother ; 120: 109555, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31669915

RESUMO

Glucagon-like peptide-1 receptor (GLP-1R) is an important pharmacological target for type 2 diabetes mellitus because it maintains glucose homeostasis and promotes ß cell proliferation. Androgen is suggested not only to regulate hypothalamic-pituitary-gonadal axis but also to affect metabolism. In this study, Glp1r mRNA was found widely expressed in normal male mice and its levels were positively correlated with the serum testosterone (T) concentrations. Using mouse insulinoma 6 (MIN6) cells, which highly express GLP-1R, we observed GLP-1R was upregulated both at transcriptional and protein levels induced by dihydrotestosterone (DHT) and was downregulated by androgen receptor inhibitor ARN-509 or small interfering RNA (siRNA) targeting Glp1r mRNA. In normal C57BL/6 mice and db/db mice, Glp1r mRNA levels in the pancreases increased in the DHT treatment group and decreased in the ARN-509 treatment group. And the increased GLP-1R expression had insulinotropic function both in vitro and in vivo. Further analysis showed that the androgen receptor (Ar) located in the cytosol of MIN6 cells and translocated to the nucleus after DHT treatment. In addition, we found that there was an Ar motif in the promoter region of the Glp1r gene. Further studies revealed that the translocated DHT/Ar complex from the cytosol to the nucleus bound to the Ar motif of the Glp1r gene and upregulated gene transcription. Taken together, the widely expressed GLP-1R was positively regulated by androgen under physiological condition and in diabetic models at the transcriptional level.


Assuntos
Androgênios/farmacologia , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Animais , Linhagem Celular , Membrana Celular/metabolismo , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Di-Hidrotestosterona/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Receptor do Peptídeo Semelhante ao Glucagon 1/genética , Secreção de Insulina/efeitos dos fármacos , Masculino , Camundongos Endogâmicos C57BL , Modelos Biológicos , Especificidade de Órgãos , Regiões Promotoras Genéticas/genética , Transporte Proteico/efeitos dos fármacos , Receptores Androgênicos/metabolismo , Maturidade Sexual , Testosterona/sangue , Transcrição Genética/efeitos dos fármacos
4.
PLoS One ; 14(9): e0216975, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31539377

RESUMO

Alpine sand dunes restoration is extremely difficult but important in the ecosystem restoration. Sand dunes are known as harsh soil and poor seed bank which freed from advantages on plants growth naturally. Effective restoration measures are required to guide the sand dune restoration. Here, indigenous grass (Elymus nutans) was sown in sand dune on the Zoige Plateau and treated with no sand barrier (CK) and environmental friendly materials including wicker sand barrier (wicker) and sandbag sand barrier (sandbag). The soil conditions were assessed by measuring the soil moisture and nutrients of the topsoil, and interspecific relationship and population niche were utilized to analyze the plant community structure variances among different restoration measures. Results showed that the soil and vegetation in the sand barriers measures were better than that in the CK. The soil moisture in the sandbag measure was 16.67% higher than that in the wicker measure. The nutrients content and microbial biomass were also the best in the sandbag measures. The ratio of strong association was the highest in the sandbag measure and the lowest in the CK, whereas the plants had the highest none association ratio in the CK. In addition, the average population niche overlap ranked by sandbag (0.39)>wicker (0.32)>CK (0.26). Thus, incorporation of sand barriers and indigenous grass seeding in alpine sand dunes could promote the sand dune restoration. And the sandbag measure showed a stronger improvement effect on the sand dune soil and vegetation conditions than the wicker measure.


Assuntos
Conservação dos Recursos Naturais , Meio Ambiente , Plantas , Areia , Solo , Algoritmos , China , Ecossistema , Modelos Teóricos
5.
Sci Rep ; 9(1): 9613, 2019 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-31270427

RESUMO

Increasing precipitation has been predicted to occur in the karst areas in southwestern regions of China. However, it is little known how various plants respond to increasing precipitation in this region. Here we determined the impacts of water addition on leaf metabolites of grasses (Cymbopogon distans and Arundinella sitosa) and shrubs (Carissa spinarum and Bauhinia brachycarpa) in this area. Four levels of water additions (CK, T1, T2 and T3 indicating 0%, +20%, +40% and +60% relative to the current monthly precipitation, respectively) were designed. Sphingolipids substantially increased in the leaves of all four species with increasing water supply which suggests that these plants adopted biochemical strategy to tolerate the wet stress. However, both shrubs showed decreases in valine and threonine (amino acids), threonate, succinate and ascorbic acid (organic acids), galactose and rhamnose (sugars) and epicatchin and oleamides (secondary metabolites) with increasing water supply. Both grasses increased in the total metabolites at T1, but the total metabolites in A. sitosa significantly decreased at T2 and T3 while remains unchanged in C. distans. Tri-carboxylic acid cycle and amino acid metabolism in shrubs and shikimate pathway in grasses were strongly affected with water supply. Overall, shrubs and grasses respond differentially to variation in water addition in terms of metabolomics, which is helpful in understanding how plants respond to climate change.


Assuntos
Irrigação Agrícola , Metabolismo Energético , Plantas/metabolismo , Poaceae/metabolismo , China , Mudança Climática , Biologia Computacional/métodos , Ecossistema , Cromatografia Gasosa-Espectrometria de Massas , Metabolismo dos Lipídeos , Redes e Vias Metabólicas , Metabolômica/métodos , Fenótipo , Folhas de Planta/metabolismo , Água
6.
Sci Rep ; 9(1): 8761, 2019 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-31217455

RESUMO

Understanding how patterns of recovery and geological conditions affect microbial communities is important for determining the stability of karst ecosystems. Here, we investigated the diversity and composition of microorganisms in karst and non-karst environments under natural restoration and artificial rehabilitation conditions. The results showed no significant differences in soil microbial diversity, but the microbial communities associated with geological conditions and tree species differed significantly. Variation partitioning analysis (VPA) showed that a total of 77.3% of the variation in bacteria and a total of 69.3% of the variation in fungi could be explained by vegetation type and geological background. There were significant differences in six bacterial classes (Actinobacteria, Alphaproteobacteria, Ktedonobacteria, TK10, Gammaproteobacteria, and Anaerolineae) and nine fungal classes (Eurotiomycetes, Agaricomycetes, unclassified _p_Ascomycota, Sordariomycetes, Tremellomycetes, norank_k_Fungi, Pezizomycetes, Leotiomycetes and Archaeorhizomycetes) among the soils collected from six plots. A Spearman correlation heatmap showed that the microbial community was affected by the major soil properties. Principal coordinates analysis indicated that the microbial community of Pinus yunnanensis in the artificial forest, which was established for the protection of the environment was most similar to that in the natural secondary forest in the karst ecosystem. These findings further our understanding of microbial responses to vegetation restoration and geological conditions.


Assuntos
Bactérias , Ecossistema , Microbiota , Rizosfera , Microbiologia do Solo , Bactérias/classificação , Bactérias/crescimento & desenvolvimento
7.
Infect Dis Poverty ; 8(1): 13, 2019 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-30732636

RESUMO

BACKGROUND: Snail control is an important component in the national schistosomiasis control programme in China, by application of chemical molluscicides, forestry projects, agriculture projects and water conservancy projects in recent decades. However, there are still wide areas of snail inhabited in China which remains a great challenge to achieve the goal of schistosomiasis elimination by 2025. Therefore, a SWOT (strengths, weaknesses, opportunities and threats) analysis on snail control measures is required for precision schistosomiasis control. METHODS: The SWOT approach, which is a well-known structured analysis tool, was used to identify and evaluate the specific characteristics of four types of snail control measures in China, including chemical mollusciciding, forestry, agriculture, and water conservancy projects. The analysis were carried out based on the information collection from literature review, of research papers, books, annual report database of national schistosomiasis control programme in China, reports from the academic forums, and so on. RESULTS: For chemical mollusciciding, application strategy needs to focus on specific local settings, such as stage of schistosomiasis control, environmental factors, and limitations from external policies and internal deficiencies. Regarding forestry projects, the optimal strategies are to cooperate with other national forestry programmes to share the investment costs and pay attention on wetland protection. In agriculture projects, it is necessary to develop related cash crop industries and combine with national farmland consolidation projects simultaneously to increase the total economic benefits. Concerning water conservancy projects, the main purpose is to control snail migration from snail area to snail-free areas nationwide. CONCLUSIONS: Integrated strategies for various measures application and a top-level designed cooperation mechanism will be the necessary to eliminate snail and schistosomiasis in China.


Assuntos
Modelos Biológicos , Moluscocidas/uso terapêutico , Controle de Pragas/métodos , Esquistossomose/prevenção & controle , Caramujos , Agricultura , Animais , China , Florestas , Humanos , Caramujos/efeitos dos fármacos , Caramujos/parasitologia
8.
Environ Sci Pollut Res Int ; 26(2): 1379-1393, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30426369

RESUMO

Efficient disposal of urban sewage sludge, material that typically contains high concentrations of heavy metals, has become a significant concern worldwide. The empirical purpose of the current study is to investigate physical and chemical parameters of composted sludge and garden waste at different ratios. Results reveal that nutrient content has significantly increased after the application of composts as compared to the controlled sample. Composting garden waste with sewage sludge at a 1:1 ratio promoted plant growth and gradually showed superiority in the later period. The maximum plant height, total biomass, and crown width of mulberry trees increased by 12.1, 33.5, and 45.7%, respectively, compared with the control treatment. The bound to organic matter of Hg, Cr, and Pb in the sewage sludge increased after composting with garden waste, and the mulberry exhibited a high ability to accumulate Ni and Cd from the soil. Conclusively, compared to using the two soil mediums separately, composting garden waste and sewage sludge together is beneficial for soil improvement and vegetation growth.


Assuntos
Compostagem , Morus/crescimento & desenvolvimento , Gerenciamento de Resíduos/métodos , China , Jardins , Mercúrio/análise , Metais Pesados/análise , Metais Pesados/farmacocinética , Morus/efeitos dos fármacos , Morus/metabolismo , Esgotos , Solo/química , Poluentes do Solo/análise , Poluentes do Solo/farmacocinética
9.
Sci Rep ; 8(1): 17606, 2018 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-30514965

RESUMO

Plant functional groups (PFGs) have been increasingly introduced in land degradation (LD) studies; however, it is unclear whether PFGs can indicate LD. Here, we selected five different degraded lands (i.e., pristine and, lightly, moderately, seriously and extremely degraded) higher than 4650 m on the Tibetan Plateau. In addition, we investigated floristic metrics (i.e., composition, height, cover, biomass and abundance) and soil conditions (e.g., moisture, temperature and gravel ratio) by sampling 225 subplots. We found 75 vascular plants that consist of sedges (Cyperaceae), grasses (Gramineae), legumes, forbs, cushion plants and shrubs PFGs. LD dramatically deteriorated soil conditions, vegetation cover and productivity, however, improved species diversity. Moreover, cover and productivity showed a hump-shaped relationship with LD intensification in legumes, grasses and forbs and decreased mainly in sedges. Productivity increased considerably in cushion plants and shrubs on the extremely degraded land. Major characteristics of the LD process were the replacement of Kobresia spp. by Carex spp. in sedges; cushion plants significantly expanded, and shrubs appeared on the extremely degraded land. We, thus, confirm that the PFG variations are likely to indicate a LD process and demonstrate ways of using PFGs to assess LD status on the Tibetan Plateau.


Assuntos
Biodiversidade , Ecossistema , Desenvolvimento Vegetal , Plantas/classificação , Solo/química , Biomassa , Plantas/anatomia & histologia , Tibet
10.
Sci Total Environ ; 643: 1502-1513, 2018 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-30189566

RESUMO

This work describes the spatial distribution of metal concentrations, resulting environmental quality, and potential ecological risks using ArcGIS. The data were based on collecting the soil background and baseline values of eight metal elements (As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn) in 31 Chinese provincial capital cities (PCCs) from published literatures 2005-2017. The following results were obtained in accordance with the integrated pollution index and the total potential ecological risk index: (1) The average concentrations of metals varied in relatively low degree in Chinese PCCs, while 10 and six PCCs were classified as having "severe" contamination and "moderate" risk, respectively. (2) Cd, Hg, Cu, Pb, and Zn were chosen as priority control metals; Beijing, Chengdu, Tianjin, Changsha, Shijiazhuang, Shenyang, Ji'nan, Changchun, and Xi'an were chosen as priority control PCCs, due to their higher pollution level and ecological risk of soils in comparison to other metals or PCCs. (3) A clear southeast/northwest boundary marked the urban soil metal pattern, which was aligned with the famous demographic, geological, and economic boundary known as the "Hu-line." This finding suggests that metal contamination in urban soil was caused by both geochemical background and human activities. These results provide basic information that can assist to avoid further degradation of soil by preventing and monitoring metal contamination in China's PCCs. The study suggests that more attention should be focused on developing cities in western China and "The Belt and Road" when pursuing economic development.

11.
EMBO J ; 37(19)2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30104406

RESUMO

In eukaryotes, heterochromatin regions are typically subjected to transcriptional silencing. DNA methylation has an important role in such silencing and has been studied extensively. However, little is known about how methylated heterochromatin regions are subjected to silencing. We conducted a genetic screen and identified an epcr (enhancer of polycomb-related) mutant that releases heterochromatin silencing in Arabidopsis thaliana We demonstrated that EPCR1 functions redundantly with its paralog EPCR2 and interacts with PWWP domain-containing proteins (PWWPs), AT-rich interaction domain-containing proteins (ARIDs), and telomere repeat binding proteins (TRBs), thus forming multiple functionally redundant protein complexes named PEAT (PWWPs-EPCRs-ARIDs-TRBs). The PEAT complexes mediate histone deacetylation and heterochromatin condensation and thereby facilitate heterochromatin silencing. In heterochromatin regions, the production of small interfering RNAs (siRNAs) and DNA methylation is repressed by the PEAT complexes. The study reveals how histone deacetylation, heterochromatin condensation, siRNA production, and DNA methylation interplay with each other and thereby maintain heterochromatin silencing.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas/fisiologia , Inativação Gênica/fisiologia , Heterocromatina/metabolismo , Histonas/metabolismo , Complexos Multiproteicos/metabolismo , Acetilação , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Heterocromatina/genética , Histonas/genética , Complexos Multiproteicos/genética
12.
Cell Death Dis ; 9(7): 717, 2018 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-29915327

RESUMO

Substantial evidence shows that long non-coding RNAs (lncRNAs) participate in many biological mechanisms, and their dysregulation are also involved in the development and progression of cancers, including gastric cancer (GC). Long intergenic non-coding RNA 00324 (LINC00324), a 2115 bp ncRNA, is located on chromosome 17p13.1. The biological function and molecular mechanisms of LINC00324 in GC remains undiscovered. In this paper, we found that the expression level of LINC00324 was significantly upregulated in GC tissues compared with the corresponding normal tissues. The overexpression of LINC00324 was correlated with advanced TNM stage, larger tumor size, and lymph node metastasis as well as poor prognosis. Further experiments revealed that knockdown of LINC00324 could suppress the proliferation of GC cells. RNA transcriptome sequencing technology revealed that FAM83B may be a significant downstream target gene of LINC00324. LINC00324 could combine with the RNA-binding protein (RBP) human antigen R (HuR) and thus stabilize the expression of FAM83B. Moreover, rescue assays showed that the reduced FAM83B expression partially reversed the promotion of cell growth in GC induced by the overexpression of LINC00324. In conclusion, our study revealed that LINC00324 acted as an oncogene in tumorigenesis and progression, suggesting that it could be a new biomarker in diagnosis and prognosis of GC.


Assuntos
Proliferação de Células/genética , Proteína Semelhante a ELAV 1/metabolismo , Proteínas de Neoplasias/genética , RNA Longo não Codificante/fisiologia , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Animais , Transformação Celular Neoplásica/genética , Células Cultivadas , DNA Intergênico , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Humanos , Metástase Linfática , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteínas de Neoplasias/metabolismo , Ligação Proteica , Estabilidade de RNA/genética , Neoplasias Gástricas/metabolismo
13.
PeerJ ; 6: e4463, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29707428

RESUMO

Melatonin is well known as a powerful free radical scavenger and exhibits the ability to prevent cell apoptosis. In the present study, we investigated the role of melatonin and its receptor MTNR1B in regulating the function of bovine granulosa cells (GCs) and hypothesized the involvement of MTNR1B in mediating the effect of melatonin on GCs. Our results showed that MTNR1B knockdown significantly promoted GCs apoptosis but did not affect the cell cycle. These results were further verified by increasing the expression of pro-apoptosis genes (BAX and CASP3), decreasing expression of the anti-apoptosis genes (BCL2 and BCL-XL) and anti-oxidant genes (SOD1 and GPX4) without affecting cell cycle factors (CCND1, CCNE1 and CDKN1A) and TP53. In addition, MTNR1B knockdown did not disrupt the effects of melatonin in suppressing the GCs apoptosis or blocking the cell cycle. Moreover, MTNR1B knockdown did not affect the role of melatonin in increasing BCL2, BCL-XL, and CDKN1A expression, or decreasing BAX, CASP3, TP53, CCND1 and CCNE1 expression. The expression of MTNR1A was upregulated after MTNR1B knockdown, and melatonin promoted MTNR1A expression with or without MTNR1B knockdown. However, despite melatonin supplementation, the expression of SOD1 and GPX4 was still suppressed after MTNR1B knockdown. In conclusion, these findings indicate that melatonin and MTNR1B are involved in BCL2 family and CASP3-dependent apoptotic pathways in bovine GCs. MTNR1A and MTNR1B may coordinate the work of medicating the appropriate melatonin responses to GCs.

14.
Environ Microbiol ; 20(7): 2386-2396, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29687609

RESUMO

The importance of assembly processes in shaping biological communities is poorly understood, especially for microbes. Here, we report on the forces that structure soil bacterial communities along a 2000 m elevational gradient. We characterized the relative importance of habitat filtering and competition on phylogenetic structure and turnover in bacterial communities. Bacterial communities exhibited a phylogenetically clustered pattern and were more clustered with increasing elevation. Biotic factors (i.e., relative abundance of dominant bacterial lineages) appeared to be most important to the degree of clustering, evidencing the role of the competitive ability of entire clades in shaping the communities. Phylogenetic turnover showed the greatest correlation to elevation. After controlling the elevation, biotic factors showed greater correlation to phylogenetic turnover than all the habitat variables (i.e., climate, soil and vegetation). Structural equation modelling also identified that elevation and soil organic matter exerted indirect effects on phylogenetic diversity and turnover by determining the dominance of microbial competitors. Our results suggest that competition among bacterial taxa induced by soil carbon contributes to the phylogenetic pattern across elevational gradient in the Tibetan Plateau. This highlights the importance of considering not only abiotic filtering but also biotic interactions in soil bacterial communities across stressful elevational gradients.


Assuntos
Bactérias/classificação , Microbiologia do Solo , Fenômenos Fisiológicos Bacterianos , Clima , Ecossistema , Microbiota , Filogenia , Solo
15.
J Integr Plant Biol ; 60(5): 362-368, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29314758

RESUMO

LHP1 mediates recruitment of the PRC2 histone methyltransferase complex to chromatin and thereby facilitates maintenance of H3K27me3 on FLC, a key flowering repressor gene. Here, we report that the PWWP domain proteins (PDPs) interact with FVE and MSI5 to suppress FLC expression and thereby promote flowering. We demonstrated that FVE, MSI5, and PDP3 were co-purified with LHP1. The H3K27me3 level on FLC was decreased in the pdp mutants as well as in the fve/msi5 double mutant. This study suggests that PDPs function together with FVE and MSI5 to regulate the function of the PRC2 complex on FLC.


Assuntos
Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/metabolismo , Flores/fisiologia , Histonas/metabolismo , Proteínas de Domínio MADS/metabolismo , Arabidopsis/genética , Arabidopsis/fisiologia , Metilação , Domínios Proteicos , Fatores de Tempo
16.
Environ Pollut ; 230: 639-647, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28711824

RESUMO

Atmospheric deposition leads to accumulation of atmospheric polycyclic aromatic hydrocarbons (PAHs) on urban surfaces and topsoils. To capture the inherent variability of atmospheric deposition of PAHs in Shanghai's urban agglomeration, 85 atmospheric bulk deposition samples and 7 surface soil samples were collected from seven sampling locations during 2012-2014. Total fluxes of 17 PAHs were 587-32,300 ng m-2 day-1, with a geometric mean of 2600 ng m-2 day-1. The deposition fluxes were categorized as moderate to high on a global scale. Phenanthrene, fluoranthene and pyrene were major contributors. The spatial distribution of deposition fluxes revealed the influence of urbanization/industrialization and the relevance of local emissions. Meteorological conditions and more heating demand in cold season lead to a significant increase of deposition rates. Atmospheric deposition is the principal pathway of PAHs input to topsoils and the annual deposition load in Shanghai amounts to ∼4.5 tons (0.7 kg km-2) with a range of 2.5-10 tons (0.4-1.6 kg km-2).


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes do Solo/análise , China , Indústrias , Estações do Ano , Análise Espaço-Temporal , Urbanização
17.
Genome Biol ; 18(1): 103, 2017 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-28569170

RESUMO

BACKGROUND: The chromodomain helicase DNA-binding family of ATP-dependent chromatin remodeling factors play essential roles during eukaryote growth and development. They are recruited by specific transcription factors and regulate the expression of developmentally important genes. Here, we describe an unexpected role in non-coding RNA-directed DNA methylation in Arabidopsis thaliana. RESULTS: Through forward genetic screens we identified PKL, a gene required for developmental regulation in plants, as a factor promoting transcriptional silencing at the transgenic RD29A promoter. Mutation of PKL results in DNA methylation changes at more than half of the loci that are targeted by RNA-directed DNA methylation (RdDM). A small number of transposable elements and genes had reduced DNA methylation correlated with derepression in the pkl mutant, though for the majority, decreases in DNA methylation are not sufficient to cause release of silencing. The changes in DNA methylation in the pkl mutant are positively correlated with changes in 24-nt siRNA levels. In addition, PKL is required for the accumulation of Pol V-dependent transcripts and for the positioning of Pol V-stabilized nucleosomes at several tested loci, indicating that RNA polymerase V-related functions are impaired in the pkl mutant. CONCLUSIONS: PKL is required for transcriptional silencing and has significant effects on RdDM in plants. The changes in DNA methylation in the pkl mutant are correlated with changes in the non-coding RNAs produced by Pol IV and Pol V. We propose that at RdDM target regions, PKL may be required to create a chromatin environment that influences non-coding RNA production, DNA methylation, and transcriptional silencing.


Assuntos
Metilação de DNA/genética , RNA Polimerases Dirigidas por DNA/genética , RNA não Traduzido/genética , Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Inativação Gênica , Mutação/genética , Regiões Promotoras Genéticas , RNA Interferente Pequeno/genética , Transcrição Genética/genética
18.
Wei Sheng Yan Jiu ; 46(1): 113-119, 2017 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-29903163

RESUMO

OBJECTIVE: Effects of boron( B) on the serum biochemical index and microstructure of immune organs in male obese rats were studied. METHODS: 40 male SD rats( 3-month old) were divided into five groups: normal control group, high-fat-diet control group and boron supplemental group of low, medium and high dose, randomly. The normal control group were fed with normal diet, the other 4 groups were fed with highfat diet to establish the model of obesity for 8 weeks. The boron supplemental group of low, medium and high dose were supplemented 20, 40 and 80 mg B / L in drinking water for 90 d, respectively. At the end, the rats were anesthetized and bled. The blood were collected from right atrium to detected the biochemical indexes related to liver function, and the thymus and spleen were obtained to weighted and fixed, then the samples were made into paraffin sections, stained with hematoxylin-eosin( HE) stain, observed and measured the histological parameters of immune organs. RESULTS: Compared with normal control group, the Lee's index and abdominal fat rate, the level of serum low density lipoprotein cholesterol( LDL-c) and the thymus weight were significantly increased( P <0. 05), but the level of serum total protein( TP) and high density lipoprotein cholesterol( HDL-c) were significantly decreased( P < 0. 05) in high-fat-diet control group, 40 mg /L and 80 mg / L supplement groups of boron. However, these detection indexes did not change significantly( P > 0. 05) in 20 mg / L supplement groups of boron. Compared with the high-fat-diet control group, the Lee's index and abdominal fat rate, the level of serum Apolipoprotein B( apo B) and LDL-c, the thymus weight and index were significantly decreased( P < 0. 05), but the level of serum TP and high density lipoprotein cholesterol( HDL-c) were significantly increased( P < 0. 05) in 20 mg /L supplement groups of boron. The level of serum LDL-c and thymus weight was significantly lower( P < 0. 05) in40 mg / L supplement groups of boron. But all the above detection indicators did not change significantly( P > 0. 05) in 80 mg / L supplement groups of boron. Under the microscope, compared with high-fat-diet control group, splenic nodule area was increased significantly( P < 0. 05), splenic periarterial lymphatic sheath, marginal zone and splenic cord were also thicker significantly( P < 0. 05), thymus medulla / cortex ratio decreased significantly( P < 0. 05), the cells arranged closely, vacuolar like structures were less in the thymus medulla of 20 mg / L and 40 mg / L supplement groups of boron. Microstructure of spleen and thymus did not change significantly in 80 mg / L supplement groups of boron. CONCLUSION: Supplementation of 20 mg B / L could decrease the level of serum apo B and LDL-c, and increase the level of serum HDL-c, and protect the liver function and immune organ of rat from damage caused obese by high fat diet.


Assuntos
Boro/farmacologia , Dieta Hiperlipídica , Obesidade/sangue , Animais , HDL-Colesterol , Suplementos Nutricionais , Água Potável , Masculino , Ratos , Ratos Sprague-Dawley
19.
PLoS One ; 11(10): e0163566, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27798642

RESUMO

Over the past several decades, rocky desertification has led to severe ecological problems in karst areas in South China. After a rocky desertification treatment project was completed, the vegetation coverage changed greatly and, consequently, increased the ecology water consumption (approximately equal to the actual evapotranspiration) of the regional vegetation. Thus, it intensified the regional water stresses. This study explored the changes in the actual evapotranspiration (ETa) response to the vegetation coverage changes in the rocky desertification areas in South China based on the precipitation (P), potential evapotranspiration (ETp) and NDVI (the normalized difference vegetation index) datasets. The revised Bagrov model was used to simulate the actual evapotranspiration changes with the supposed increasing NDVI. The results indicated that the average NDVI value was lower when the rocky desertification was more severe. The ETa, evapotranspiration efficiency (ETa/ETp) and potential humidity (P/ETp) generally increased with the increasing NDVI. The sensitivity of the ETa response to vegetation coverage changes varied due to different precipitation conditions and different rocky desertification severities. The ETa was more sensitive under drought conditions. When a drought occurred, the ETa exhibited an average increase of 40~60 mm with the NDVI increasing of 0.1 in the rocky desertification areas. Among the 5 different severity categories of rocky desertification, the ETa values' responses to NDVI changes were less sensitive in the severe rocky desertification areas but more sensitive in the extremely and potential rocky desertification areas. For example, with the NDVI increasing of 0.025, 0.05, 0.075, and 0.1, the corresponding ETa changes increased by an average of 2.64 mm, 10.62 mm, 19.19 mm, and 27.58 mm, respectively, in severe rocky desertification areas but by 4.94 mm, 14.99 mm, 26.80, and 37.13 mm, respectively, in extremely severe rocky desertification areas. Understanding the vegetation ecological water consumption response to the vegetation coverage changes is essential for the vegetation restoration and water stresses mitigation in rocky desertification areas.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Meio Ambiente , Plantas , Água , China , Ecologia , Monitoramento Ambiental , Geografia , Chuva , Análise Espacial
20.
Huan Jing Ke Xue ; 37(4): 1546-52, 2016 Apr 15.
Artigo em Chinês | MEDLINE | ID: mdl-27548981

RESUMO

A total of 6 thermophilic cellulase-producing strainswere isolated from organic garden waste mixed chicken composting at thermophilic period. These isolates were identified as Streptomyces thermoviolaceus, S. thermodiastaticus, S. thermocarboxydus, S. albidoflavus, S. thermovulgaris and Brevibacillus borstelensis through 16S rRNA gene sequence alignment and phylogenetic tree analysis. The cellulose-degrading microbial community has been investigated in few researches so far both at home and abroad. In this study, the mixed strains M-1 was made up of the 6 cellulose-decomposing microorganisms. The CMCase activity of the mixed strains M- 1 was stronger than any of the 6 single strains. Production of CMCase from mixed strains M-1 was studied by optimizing different physico-chemical parameters. The Maximum CMCase production (135.9 U · mL⁻¹) of strains M-1 was achieved at 45 °C in a liquid medium (pH 4) inoculated with 1% (volume fraction), containing a mixture of wheat bran and starch, corn flour and KNO3. After optimization of separation conditions, CMCase production capacity was improved by 1.8 times.


Assuntos
Proteínas de Bactérias/metabolismo , Celulase/metabolismo , Microbiologia Industrial , Filogenia , Streptomyces/enzimologia , Proteínas de Bactérias/genética , Celulase/genética , Celulose/metabolismo , Genes Bacterianos , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Streptomyces/classificação , Streptomyces/genética
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