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1.
J Nanosci Nanotechnol ; 20(5): 3105-3116, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31635654

RESUMO

The Z-scheme Bi2WO6/NaBiO3 nanocomposites were first fabricated by a facile hydrothermal method, and were then characterized by X-ray diffraction, transmission electron microscopy, scanning electron microscopy, energy dispersive spectrometer, Fourier-transform-infrared spectroscopy, X-ray photoelectron spectroscopy and N2 adsorption-desorption. The as-prepared Bi2WO6/NaBiO3 nanocomposites exhibit outstanding photocatalytic activity and recyclability. A 98.4% photodegradation of 2,3-dichlorophenol (50 mg·L-1) was attained in the presence of Bi2WO6/NaBiO3 (1:10) under the visible-light irradiation in 30 min. In particular, the photocatalytic mechanism has been discussed in detail, based on four aspects: (1) oxidative species, (2) photoelectrochemical performance, (3) conduction band and valence band energy levels and (4) possible transition states and reactions. In conclusion, O-2 is the main active oxidative species in the Bi2WO6/NaBiO3 nanocomposite. The material has higher photocurrent and visible light adsorption but lower electron-hole pairs recombination, which contributes to distinguished photocatalytic efficiency. The Z-scheme photocatalytic path was proposed and the possible degradation process and routes have been summarized.

2.
Artigo em Inglês | MEDLINE | ID: mdl-31674893

RESUMO

Two strains, designated 2251T and 3058, that were aerobic, Gram-stain-negative, non-motile, coccoid or short rod-shaped bacilli, have recently been isolated from Tibetan antelopes on the Qinghai-Tibet Plateau. The results of phylogenetic analyses of 16S rRNA gene sequences indicated that strains 2251T and 3058 represent a new species within the genus Paracoccus and are most similar to 'Paracoccus gahaiensis' CUG00006T (98.9 and 99.3 %), Paracoccus nototheniae I-41R45T (98.3 and 98.7 %) and Paracoccus hibiscisoli THG-T2.31T (97.6 and 97.8 %). Results of genomic sequence-based phylogenomic analysis agreed with those from 16S rRNA gene sequence analysis. Optimal growth was achieved at pH 7.0-7.5 and 28 °C with marine medium. Cells contained C18 : 1 ω7c as the major cellular fatty acid and ubiquinone-10 as the predominant menaquinone. The polar lipids comprised phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol, phospholipid, glycolipid and an unidentified lipid. The cell-wall peptidoglycan amino acids were meso-2,6-diaminopimelic acid, alanine and glutamic acid; the major cell-wall sugar was galactose. The G+C content of strain 2251T was 66.5 mol%. Both strains (2251T and 3058) had DNA-DNA relatedness values less than 50 % with all available genomes of the genus Paracoccus in the ncbi database. Differential genotypic inferences, together with phenotypic and biochemical characteristics, demonstrated that strains 2251T and 3058 should be classified as a novel species of the genus Paracoccus, for which the name Paracoccus liaowanqingii sp. nov. is suggested. The type strain is 2251T (=CGMCC 1.16490T=DSM 106269T).

3.
Opt Express ; 27(20): 28104-28113, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31684568

RESUMO

A compact and high sensitivity refractive index (RI) sensor has been theoretically and experimentally demonstrated based on dual-mode interferometer (DMI) in an eccentric core few-mode fiber (ECFMF). The DMI is fabricated by fusion splicing a piece of ECFMF etched by hydrofluoric acid (HF) and two single mode fibers (SMFs) with a lateral-offset. The interference is formed by LP01 and LP11 modes in the eccentric core of ECFMF. The etched ECFMF-DMI based on core-core mode interference exhibits a higher RI sensitivity than the DMI based on core-cladding mode interference. The sensitivity reaches up to 2565.2 nm/RIU around the RI of 1.4. Both of the etched and unetched ECFMF-DMIs have low temperature sensitivities of 9.6 pm/°C and 33.1 pm/°C, respectively. The etched ECFMF-DMI based on the core-core mode interference possesses tremendous superiority for RI measurement due to its high RI sensitivity and low temperature cross, therefore the proposed sensor has great potentials in chemical and biological fields.

4.
BMJ Open ; 9(11): e031337, 2019 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-31685508

RESUMO

OBJECTIVES: To assess the prevalence of visual impairment (VI) and blindness (BL) due to cataract and cataract surgical outcomes in remote dispersed and high-altitude Tibetan areas of China. DESIGN AND SETTING: A cross-sectional study was conducted among people aged 50 and above in Tibetan Autonomous Prefecture of Kandze (TAPK), China, in 2017. The Rapid Assessment of Avoidable Blindness protocol was followed. PARTICIPANTS: Of 5000 eligible participants, 4764 were examined (response rate 95.3%). PRIMARY AND SECONDARY OUTCOME MEASURES: Cataract VI was defined as lens opacity at visual acuity (VA) levels of <3/60 (Blindness (BL)), ≥3/60 and <6/60 (severe visual impairment (SVI)), ≥6/60 and <6/18 (moderate visual impairment (MVI)), ≥6/18 and <6/12 (early visual impairment (EVI)). RESULTS: The estimated prevalence of cataract BL was 0.61% (95% CI 0.42 to 0.87). With best corrected VA, the estimated prevalence of SVI from cataract was 0.86% (95% CI 0.63 to 1.17); MVI was 2.39% (95% CI 2.00 to 2.87) and EVI was 5.21% (95% CI 4.61 to 5.87). Women in TAPK had a significantly higher prevalence of cataract BL (0.82%, 95% CI 0.54 to 2.15) than men (0.34%, 95% CI 0.16 to 0.70). Women had lower cataract surgical coverage (CSC) by eyes (60.8%, 95% CI 55.5 to 65.8) compared with men (70.1%; 95% CI 63.7 to 75.7). The prevalence of cataract BL was higher among Tibetan (2.28%; 95% CI 1.98 to 2.62) than Han Chinese (1.01%%; 95% CI 0.54% to 1.87%). Overall CSC by person with BL (by better eye) was 82.0% (95% CI 75.2 to 87.6). Among cataract-operated participants, 71.2% had VA equal to or better than 6/18. CONCLUSIONS: The study detected a low prevalence of VI and BL due to cataract with high CSC in the study area compared with many other places in China. Further actions should be taken to improve cataract surgical outcome.

5.
Dalton Trans ; 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31687705

RESUMO

Herein, we have studied the crystallization of zeolite omega by the solid-state transformation of TMA-magadiite at 100 °C for 12 h. The samples prepared at different times were subjected to XRD, SEM, IR, Raman and solid MAS NMR analyses to investigate the crystallization behaviors and changes in the medium-range structure during the synthesis process and a comprehensive mechanism was proposed. It has been demonstrated that the 5Rs and 6Rs in magadiite are partially retained in the system and participate in the growth of zeolite omega. The 4Rs were formed after heating for 4 h. The synthesis time of the zeolite omega using this method is shorter than that using the magadiite hydrothermal conversion method (about 72 h), because special composition building units, which have similarities to the structure of zeolite omega, were formed and adsorbed on the surface of the TMA-magadiite, and then provided a growth surface for the synthesis of targets. In addition, recycling the waste mother liquid produced in the preparation of the precursor was done to achieve the low cost and green synthesis. Finally, several factors influencing the reaction are discussed.

6.
Mol Cell ; 2019 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-31668930

RESUMO

High-resolution Cas9 structures have yet to reveal catalytic conformations due to HNH nuclease domain positioning away from the cleavage site. Nme1Cas9 and Nme2Cas9 are compact nucleases for in vivo genome editing. Here, we report structures of meningococcal Cas9 homologs in complex with sgRNA, dsDNA, or the AcrIIC3 anti-CRISPR protein. DNA-bound structures represent an early step of target recognition, a later HNH pre-catalytic state, the HNH catalytic state, and a cleaved-target-DNA-bound state. In the HNH catalytic state of Nme1Cas9, the active site is seen poised at the scissile phosphodiester linkage of the target strand, providing a high-resolution view of the active conformation. The HNH active conformation activates the RuvC domain. Our structures explain how Nme1Cas9 and Nme2Cas9 read distinct PAM sequences and how AcrIIC3 inhibits Nme1Cas9 activity. These structures provide insights into Cas9 domain rearrangements, guide-target engagement, cleavage mechanism, and anti-CRISPR inhibition, facilitating the optimization of these genome-editing platforms.

7.
Free Radic Biol Med ; 2019 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-31669760

RESUMO

The Nrf2-Keap1 pathway regulates transcription of a wide array of antioxidant and cytoprotective genes and offers critical protection against oxidative stress. This pathway has demonstrated benefit for a variety of retinal conditions. Retinal ischemia plays a pivotal role in many vision threatening diseases. Retinal vascular endothelial cells are an important participant in ischemic injury. In this setting, Nrf2 provides a protective pathway via amelioration of oxidative stress and inflammation. In this study, we investigated a potent small molecule inhibitor of the Nrf2-Keap1 protein-protein interaction (PPI), CPUY192018, for its therapeutic potential in retinal cells and retinal ischemia-reperfusion injury. In human retinal endothelial cells (HREC), treatment with CPUY192018 increased Nrf2 protein levels and nuclear translocation, stimulated Nrf2-ARE-induced transcriptional capacity, and induced Nrf2 target gene expression. Furthermore, CPUY192018 protected HREC against oxidative stress and inflammatory activation. CPUY192018 also activated Nrf2 and suppressed inflammatory response in macrophages. In the retinal ischemia-reperfusion (I/R) model, administration of CPUY192018 induced Nrf2 target gene activation in the retina. Both systemic and topical treatment with CPUY192018 rescued visual function after ischemia-reperfusion injury. Taken together, these findings indicate that small molecule Keap1-Nrf2 PPI inhibitors can activate the Nrf2 pathway in the retina and provide protection against retinal ischemic and inflammatory injury, suggesting Keap1-Nrf2 PPI inhibition in the treatment of retinal conditions.

8.
Biomed Pharmacother ; 120: 109546, 2019 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-31675687

RESUMO

Cervical cancer (CC) is one of the most common cancers in women. However, copy number alteration (CNA)-driven dysregulated genes and their functions in CC are still rarely investigated. In the present study, we conducted integrative analysis of CNA and gene expression data from The Cancer Genome Atlas (TCGA) cervical cancer to identify dysregulated genes triggered by CNAs. The integration of copy number status and RNA expression revealed 763 amplified and 1,391 deleted genes significantly dysregulated by the CNAs (P-value < 1e-8). Among these CNA genes, five driver genes, including PI3KCA, PI3KCB, DVL3, WWTR1, and ERBB2, exhibited a strong association with immune cell infiltration, suggesting that the pathways that they participate in may be involved in regulating immune cell infiltration. Moreover, we also observed that the genes of immunotherapeutic targets were abundantly expressed in the wild-type samples, suggesting that immunotherapy based on these immunotherapeutic targets may be applied to wild-type samples. In addition, the two CNA driver genes, DVL3 and ERBB2, might be sensitive and resistant biomarkers for examining the tumor's response to chemoradiotherapy, respectively. Particularly, the expression of ERBB2 was also observed to be higher in responders of chemotherapy than non-responders. Furthermore, a subset of CNA genes was identified to predict the prognosis of cervical cancer. In summary, our systematic data analysis of these CNA genes not only improved our understanding of the veiled mechanism behind immune cell infiltration, but also provided the potential clinical application of these CNA genes in cervical cancer.

9.
BMC Pregnancy Childbirth ; 19(1): 396, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31675921

RESUMO

BACKGROUND: Hypertensive disorders of pregnancy (HDP) are characterized by hemodynamic disturbances. Altered thyroid function is a risk factor for poor outcomes of pregnancy. However, the associations between thyroid function biomarkers and maternal hemodynamics during pregnancy in HDP remain unclear. METHODS: From January 2016 to January 2018, pregnant women diagnosed with HDP admitted to the Nanjing Maternity and Child Health Care Hospital were prospectively enrolled in the third trimester. Normally distributed variables were expressed as mean ± standard deviation and skewed variables were expressed as median (25th percentile, 75th percentile). Correlations between thyroid-stimulating hormone (TSH) or free thyroxine (FT4) and maternal hemodynamic parameters were assessed by Pearson's correlation coefficient and 95% confidence interval (95%CI). Bonferroni's correction for multiple correlations was performed. Logistic regression models with odd ratio (OR) and 95%CI were applied to confirm the associations. RESULTS: A total of 163 third-trimester pregnant women with HDP with a mean gestational age of 35.62 ± 2.83 weeks were recruited. The infant birth weight of patients with elevated TSH levels was lower than that of patients with normal TSH levels (2635 ± 867 g vs. 3037 ± 673 g, p = 0.002). Reduced cardiac output (CO) was defined as CO < 3.5 L/min. The infant birth weight of patients with reduced CO was lower than that of patients with normal CO (2250 ± 510 g vs. 2890 ± 774 g, p = 0.002). TSH levels were significantly and negatively correlated with CO (r = - 0.260, 95%CI: - 0.392- -0.103, p < 0.001). FT4 levels were not significantly correlated with any of the maternal hemodynamic parameters (all p > 0.05). TSH level (OR = 1.371, 95%CI: 1.086-1.733, p = 0.008) was confirmed associated with reduced CO in the logistic regression analysis. CONCLUSIONS: Elevated TSH levels are associated with reduced CO in HDP during the third trimester.

10.
PLoS One ; 14(11): e0224962, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31697744

RESUMO

Nitrate signaling integrates and coordinates gene expression and plant growth; however, the underlying molecular mechanisms involved remain poorly understood. Our previous study revealed that rice calcineurin B-like protein 1 (OsCBL1) modulates lateral root elongation by affecting auxin biosynthesis. Here, we report that OsCBL1 also modulates nitrate signaling to regulate rice seedlings growth. Compared with wild-type seedlings, seedlings of OsCBL1-knockdown (OsCBL1-KD) plants showed a suppressed growth phenotype, which included reduced root and shoot fresh weights and shorter radicles, crown roots, and lateral roots, when grown in nitrogen-free conditions. Although the growth defects of OsCBL1-KD plants could be partially rescued by the addition of nitrate to the growth conditions, the nitrate uptake capability of the OsCBL1-KD plants did not differ from that of wild-type plants as assessed via nitrate content and 15NO3- influx experiments. The nitrate-regulated expression of nitrate signal sentinel genes (OsNRT2.1 and OsNRT2.2) was affected in the OsCBL1-KD plants under both long- and short-term nitrate treatments. Overall, our results showed a novel role for OsCBL1 in the regulation of nitrate signaling and nitrate-mediated rice growth.

11.
Sci Total Environ ; 700: 134384, 2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31698275

RESUMO

The accuracy of carbon dioxide (CO2) emissions at the provincial-level is urgently needed for China to peak CO2 emission and implement a carbon reduction plan. However, the current estimation methods have some drawbacks, such as not meeting China's situation, data obsolescence, and relatively high uncertainty. Moreover, there are large differences in estimated results among previous studies. To address these problems, this paper proposes a new provincial-level energy-related CO2 emission estimation method refer to methods at different levels in China and abroad. We re-divide the energy involved in a province based on energy flow and consumption-based responsibility and propose an accounting method for calculating provincial-level CO2 emission factors, which provides clear cross-provincial emission allocation and accurate provincial-level emission estimation. By taking Shandong Province as an example, we calculate the provincial-level CO2 emission factors and obtain the CO2 emissions from 2000 to 2016. Furthermore, the reasons for the large gaps between calculated CO2 emissions in Shandong are further quantitatively analyzed from the perspective of the method and data selection. The results indicate that although different methods greatly influence the estimation results, the gaps that arise from different selections of calculation scope, energy classification, activity data and CO2 emission factor within a method also require attention. Finally, some recommendations are proposed when making CO2 emission calculations or comparisons.

12.
BMC Public Health ; 19(1): 1470, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31699058

RESUMO

BACKGROUND: The quality of the family environment-in particular, the kind of parenting children receive in their early years-plays a critical role in influencing children's growth and development. To facilitate the development and delivery of appropriate parenting and family interventions for Chinese parents, this study explores the prevalence of the difficulties that may arise in the course of child-rearing, the associated sociodemographic factors and parents' help-seeking behavior. METHODS: A cross-sectional self-reporting survey was conducted with a sample of 2229 parents of children between 6 and 35 months of age. Using a stratified random-digit design, parents from 15 Chinese cities were surveyed to determine their child-rearing difficulties, support-seeking behavior and their preferences for service delivery. The sociodemographic factors that influenced major child-rearing difficulties were analyzed using bivariate and logistic analyses. RESULTS: The majority (87.5%) of Chinese parents of children aged 6-35 months reported experiencing child-rearing difficulties. Nearly one third (31.5%) of parents reported experiencing major difficulties. Feeding and sleep problems were most often reported. Regression analysis revealed that major child-rearing difficulties most often involved male children (OR = 1.35, 95% CI 1.11-1.64), single-child households (OR = 1.38, 95% CI 1.07-1.77), and households with financial problems (OR = 1.40, 95% CI 1.06-1.85). Just over one third of parents (33.44%) sought professional support, while 21.37% had attended a parenting course in the past year. Prefer ways of sourcing parental support included professional online platform (69.24%), self-help books (43.70%), face-to-face consultation (24.99%), and attending lectures (36.57%). CONCLUSIONS: Child-rearing difficulties are common among parents of children between 6 and 35 months of age in Chinese cities. The family with boys, single-child, financial problems, and father not joining in child-rearing may face the high risk to major child-rearing difficulties. The national initiative to provide more guidance and support for child-rearing difficulties is worthwhile, as is the development of online parenting programs.

13.
Prog Neurobiol ; : 101721, 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31704315

RESUMO

Although exogenous nerve growth factor demonstrated great potential for post-traumatic stress disorder (PTSD) treatment, its therapeutic effect and underlying cytological mechanism were not fully elucidated so far. We employed a controlled, prospectively designed modified single prolonged stress mice model to investigate the role of exogenous nerve growth factor on the modified single prolonged stress induced PTSD-like symptoms and hippocampal cytoarchitecture impairment, as well as the potential neuronal signaling modulation. We discovered that the modified single prolonged stress-exposure induced significant PTSD-like symptoms as well as mildly impaired hippocampal Cornu Ammonis 1 (CA1) subregion cytoarchitecture, but not dentate gyrus neurogenesis, together with a gradual inhibition of TrkA-CREB-ERK signalings in hippocampal CA1 subregion. Nerve growth factor (NGF) treatment dose-dependently ameliorated the modified single prolonged stress induced PTSD-like symptoms. NGF increased the cytoplasm/nucleus ratio and improved the neuronal plasticity, mainly via the TrkA-CREB-ERK pathway. Our study offered the translational evidence for the potential application of exogenous NGF for treating or early preventing PTSD after stress exposure.

14.
J Virol Methods ; 275: 113757, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31669331

RESUMO

The outbreak of an infectious disease characterized by severe symptom of gout has set great threat to several major goose-producing regions in China since December 2016. The causative agent for the novel infection has been identified was a novel goose-origin astrovirus (GoAstV). Lack of effective detection methods indeed hinders further research, as well as prevention and control of GoAstV. Keep this in mind, a TaqMan-based one-step real-time quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) assay for rapid detection of GoAstV was developed. Primers and probe were targeting the capsid protein gene sequence (ORF2). The method is capable of detecting quite low number of targeting nucleic acid as low as 10 copies/µL. What's more, it is also of great specificity and repeatability for GoAstV detection. No cross-activity was found with other goose-origin viruses. The assay had excellent intra-assay and inter-assay repeatability with the coefficient of variation (CV) value from 0.48% to 0.99%. A total of 340 GoAstV specimens from different regions of China were used in this study to verify the feasibility and effectiveness of this method in clinical diagnosis. The results indicated that qRT-PCR is a highly sensitive, specific and repeatable method for quantitative detection of GoAstV, which can be used to detect this virus, thereby facilitating epidemiological investigations of gout in goslings.

15.
Fitoterapia ; 139: 104400, 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31669962

RESUMO

Two novel epimer pairs of acetaminophen derivatives penicilquei A-D (1-4) were isolated from Penicillium herquei JX4. Their structures were elucidated using comprehensive spectroscopic methods. The absolute configurations of penicilquei A-D (1-4) were determined by modifified Mosher's method, and comparing their experimental and calculated electronic circular dichroism (ECD) spectra. Penicilquei A-D (1-4) are the first example of acetaminophen derivatives featuring an unprecedented carbon skeleton. The inhibitory activities of all compounds against nine phytopathogenic fungi and α-glucosidase were evaluated. Penicilquei A-D (1-4) showed strong inhibitory activities against at least eight phytopathogenic fungus.

16.
Lett Appl Microbiol ; 2019 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-31705810

RESUMO

Candida albicans is an opportunistic fungus, which causes vulvovaginal candidiasis (VVC). The aim of this study was to evaluate Mrr2 mutation and its expression levels and Candida drug resistance 1 (Cdr1) in C. albicans associated with fluconazole (FCA) resistance. We identified 80 isolates of C. albicans from 155 vaginal secretions and performed FCA drug sensitivity tests, using M27-A3 micro-broth dilution. We extracted DNA, sequenced Mrr2, and performed reverse transcriptase-quantitative PCR polymerase chain reaction (RT-qPCR) to detect mRNA expression levels of Mrr2 and Cdr1. In total, 40 isolates were sensitive, 10 were dose-dependently sensitive, and 30 were resistant to FCA. Mrr2 mutation occurred in 56·67% isolates, which was significantly higher than that in the FCA sensitive group (26·08%, P < 0·05). The mRNA expression level of Cdr1 in the FCA resistant group was significantly higher than that in the sensitive group Cdr1 (0·42 ± 0·294 VS 0·25 ± 0·289, P < 0·05). The odds ratio of FCA-resistant occurrence in C. albicans with Mrr2 mutation and high expression levels was 47·5 times higher than C. albicans without Mrr2 mutation and low expression levels. The results may provide new insights for improving VVC treatment.

17.
J Clin Immunol ; 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31696364

RESUMO

Autosomal recessive agammaglobulinemia (ARA) is a primary immunodeficiency characterized by absent peripheral B cells, severe hypogammaglobulinemia, and absent BTK gene mutations. In ARA, mutations occur in genes encoding the pre-B cell receptor (pre-BCR) or downstream signaling proteins. In this work, we used candidate gene and whole-exome sequencing to investigate the molecular basis of ARA in 6 patients from 4 consanguineous North-African families. Sanger sequencing of candidate genes encoding the pre-BCR components (ΙGΗΜ, CD79A, CD79B, IGLL1, and VPREB1) was initially performed and determined the genetic defect in five patients. Two novel mutations in IGHM (p.Val378Alafs*1 and p.Ile184Serfs*21) were identified in three patients from two unrelated kindred and a novel nonsense mutation was identified in CD79A (p.Trp66*) in two siblings from a third kindred. Whole-exome sequencing (WES) was performed on the sixth patient who harbored a homozygous stop mutation at position 407 in the RAG2 gene (p.Glu407*). We concluded that conventional gene sequencing, especially when multiple genes are involved in the defect as is the case in ARA, is costly and time-consuming, resulting in delayed diagnosis that contributes to increased morbidity and mortality. In addition, it fails to identify the involvement of novel and unsuspected gene defects when the phenotype of the patients is atypical. WES has the potential to provide a rapid and more accurate genetic diagnosis in ARA, which is crucial for the treatment of the patients.

18.
Autophagy ; : 1-21, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31696776

RESUMO

Macroautophagy/autophagy plays key roles in development, oncogenesis, and cardiovascular and metabolic diseases. Autophagy-specific class III phosphatidylinositol 3-kinase complex I (PtdIns3K-C1) is essential for autophagosome formation. However, the regulation of this complex formation requires further investigation. Here, we discovered that STYK1 (serine/threonine/tyrosine kinase 1), a member of the receptor tyrosine kinases (RTKs) family, is a new upstream regulator of autophagy. We discovered that STYK1 facilitated autophagosome formation in human cells and zebrafish, which was characterized by elevated LC3-II and lowered SQSTM1/p62 levels and increased puncta formation by several marker proteins, such as ATG14, WIPI1, and ZFYVE1. Moreover, we observed that STYK1 directly binds to the PtdIns3K-C1 complex as a homodimer. The binding with this complex was promoted by Tyr191 phosphorylation, by means of which the kinase activity of STYK1 was elevated. We also demonstrated that STYK1 elevated the serine phosphorylation of BECN1, thereby decreasing the interaction between BECN1 and BCL2. Furthermore, we found that STYK1 preferentially facilitated the assembly of the PtdIns3K-C1 complex and was required for PtdIns3K-C1 complex kinase activity. Taken together, our findings provide new insights into autophagy induction and reveal evidence of novel crosstalk between the components of RTK signaling and autophagy.Abbreviations: AICAR: 5-aminoimidazole-4-carboxamide ribonucleotide; AMPK: adenosine 5'-monophosphate (AMP)-activated protein kinase; ATG: autophagy related; ATP: adenosine triphosphate; BCL2: BCL2 apoptosis regulator; BECN1: beclin 1; Bre A: brefeldin A; Co-IP: co-immunoprecipitation; CRISPR: clustered regularly interspaced short palindromic repeats; DAPI: 4',6-diamidino-2-phenylindole; EBSS: Earle's balanced salt solution; GAPDH: glyceraldehyde-3-phosphate dehydrogenase; GFP: green fluorescent protein; GSEA: gene set enrichment analysis; MAP1LC3/LC3, microtubule associated protein 1 light chain 3; MAPK8/JNK1: mitogen-activated protein kinase 8; mRFP: monomeric red fluorescent protein; MTOR: mechanistic target of rapamycin kinase; MTT: 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide; PIK3C3: phosphatidylinositol 3-kinase catalytic subunit type 3; PIK3R4: phosphoinositide-3-kinase regulatory subunit 4; qRT-PCR: quantitative reverse transcription PCR; RACK1: receptor for activated C kinase 1; RUBCN: rubicon autophagy regulator; siRNA: small interfering RNA; SQSTM1: sequestosome 1; STYK1/NOK: serine/threonine/tyrosine kinase 1; TCGA: The Cancer Genome Atlas; Ub: ubiquitin; ULK1: unc-51 like autophagy activating kinase 1; UVRAG: UV radiation resistance associated; WIPI1: WD repeat domain, phosphoinositide interacting 1; ZFYVE1: zinc finger FYVE-type containing 1.

19.
BMC Genomics ; 20(1): 776, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31653200

RESUMO

BACKGROUND: Aphid (Macrosiphoniella sanbourni) stress drastically influences the yield and quality of chrysanthemum, and grafting has been widely used to improve tolerance to biotic and abiotic stresses. However, the effect of grafting on the resistance of chrysanthemum to aphids remains unclear. Therefore, we used the RNA-Seq platform to perform a de novo transcriptome assembly to analyze the self-rooted grafted chrysanthemum (Chrysanthemum morifolium T. 'Hangbaiju') and the grafted Artermisia-chrysanthemum (grafted onto Artemisia scoparia W.) transcription response to aphid stress. RESULTS: The results showed that there were 1337 differentially expressed genes (DEGs), among which 680 were upregulated and 667 were downregulated, in the grafted Artemisia-chrysanthemum compared to the self-rooted grafted chrysanthemum. These genes were mainly involved in sucrose metabolism, the biosynthesis of secondary metabolites, the plant hormone signaling pathway and the plant-to-pathogen pathway. KEGG and GO enrichment analyses revealed the coordinated upregulation of these genes from numerous functional categories related to aphid stress responses. In addition, we determined the physiological indicators of chrysanthemum under aphid stress, and the results were consistent with the molecular sequencing results. All evidence indicated that grafting chrysanthemum onto A. scoparia W. upregulated aphid stress responses in chrysanthemum. CONCLUSION: In summary, our study presents a genome-wide transcript profile of the self-rooted grafted chrysanthemum and the grafted Artemisia-chrysanthemum and provides insights into the molecular mechanisms of C. morifolium T. in response to aphid infestation. These data will contribute to further studies of aphid tolerance and the exploration of new candidate genes for chrysanthemum molecular breeding.

20.
Artigo em Inglês | MEDLINE | ID: mdl-31619042

RESUMO

In the field of all-polymer solar cells, exploring new electron-donating units (D) to match with electron-accepting units (A) is an important subject to promote the performance of D-A-type polymer acceptors. Herein, we developed a fused D unit 2-(thiophen-2-yl)thieno[3,2-b]thiophene (T-TT) derivated from the famous 2-(2-(thiophen-2-yl)vinyl)thiophene (TVT) unit. With classical naphthalene diimide (NDI) as A unit, the new D-A polymer PNDI-T-TT exhibits enhanced absorption coefficient, electron mobility, and miscibility with donor polymer in comparison with the analogous PNDI-TVT polymer. These advantages can be attributed to the enlarged conjugation and reduced rotamers due to the fused T-TT unit, leading to a stronger intermolecular interaction. When blending with the donor polymer PBDB-T, both NDI-based polymers can form better interpenetrating nanostructures than the corresponding blend films with the donor polymer J71. Finally, PBDB-T/PNDI-T-TT device achieves a power conversion efficiency of 6.1%, which is much higher than that of PBDB-T/PNDI-TVT device (4.24%). These results demonstrate that n-type polymer based on fused T-TT unit can ameliorate the absorption coefficient, molecular aggregation, and charge-carrier mobility and consequently achieve an improved photovoltaic performance in comparison with the classic TVT unit.

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