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1.
Genes Dev ; 38(1-2): 4-10, 2024 02 13.
Article in English | MEDLINE | ID: mdl-38233109

ABSTRACT

B lineage priming by pioneer transcription factor EBF1 requires the function of an intrinsically disordered region (IDR). Here, we examine the role of regularly spaced tyrosines in the IDR as potential determinants of IDR function and activity of EBF1. We found that four Y > A mutations in EBF1 reduced the formation of condensates in vitro and subdiffractive clusters in vivo. Notably, Y > A mutant EBF1 was inefficient in promoting B cell differentiation and showed impaired chromatin binding, recruitment of BRG1, and activation of specific target genes. Thus, regularly spaced tyrosines in the IDR contribute to the biophysical and functional properties of EBF1.


Subject(s)
B-Lymphocytes , Gene Expression Regulation , Cell Lineage/genetics , Transcription Factors/genetics , Transcription Factors/metabolism , Heterochromatin/metabolism
2.
Pharmaceuticals (Basel) ; 14(11)2021 Nov 04.
Article in English | MEDLINE | ID: mdl-34832906

ABSTRACT

The aim of this study was to evaluate the remineralization and antibacterial effect of silver-containing mesoporous bioactive glass (MBG-Ag) sealing combined with Er:YAG laser irradiation on human demineralized dentin specimens in a Streptococcus mutans cultivated environment. A total of 48 human dentin specimens were randomly divided into four groups. The characteristics of MBG-Ag and the occlusion efficiency of the dentinal tubules were analyzed using X-ray diffraction patterns, Fourier-transform infrared spectroscopy, scanning electron microscope images and energy dispersive X-ray spectroscopy. Moreover, the antibacterial activity against Streptococcus mutans was evaluated by colony formation assay. The results showed that the dentin specimens with Er:YAG laser irradiation can form a melted occlusion with a size of 3-4 µm. MBG-Ag promoted the deposition of numerous crystal particles on the dentinal surface, reaching the deepest penetration depth of 70 µm. The results suggested that both MBG-Ag and laser have the ability to enhance the remineralization and precipitation of hydroxyapatite crystals. While the results showed that MBG-Ag sealing combined with the thermomechanical subablation mode of Er:YAG laser irradiation-induced dense crystalline deposition, reaching a penetration depth of more than 300 µm, silver nanoparticles without good absorption of the Er:YAG laser resulted in a heterogeneous radiated surface. Er:YAG laser irradiation with a low energy and pulse rate cannot completely inhibit the growth of S. mutans, but MBG-Ag sealing reached the bactericidal concentration. It was concluded that the simultaneous application of MBG-Ag sealing and Er:YAG laser treatment can prevent the drawbacks of their independent uses, resulting in a superior form of treatment for dentin hypersensitivity.

3.
Polymers (Basel) ; 13(9)2021 May 10.
Article in English | MEDLINE | ID: mdl-34068784

ABSTRACT

Acinetobacter baumannii (A. baumannii) is a common and challenging pathogen of nosocomial infections, due to its ability to survive on inanimate objects, desiccation tolerance, and resistance to disinfectants. In this study, we investigated an antibacterial strategy to combat A. baumannii via the combination of antibiotics and silver protein. This strategy used a functional platform consisting of silver nanoparticles (AgNPs) resurrected from silver-based calcium thiophosphate (SSCP) through casein and arginine. Then, the silver protein was combined with tigecycline, the first drug in glycylcycline antibiotic, to synergistically inhibit the viability of A. baumannii. The synergistic antibacterial activity was confirmed by the 96-well checkerboard method to determine their minimum inhibitory concentrations (MIC) and calculated for the combination index (CI). The MIC of the combination of silver protein and tigecycline (0.31 mg/mL, 0.16 µg/mL) was significantly lower than that of the individual MIC, and the CI was 0.59, which indicates a synergistic effect. Consequently, we integrated the detailed synergistic antibacterial properties when silver protein was combined with tigecycline. The result could make for a promising approach for the treatment of A. baumannii.

4.
Immunity ; 53(6): 1151-1167.e6, 2020 12 15.
Article in English | MEDLINE | ID: mdl-33159853

ABSTRACT

Establishment of B-lineage-specific gene expression requires the binding of transcription factors to inaccessible chromatin of progenitors. The transcription factor EBF1 can bind genomic regions prior to the detection of chromatin accessibility in a manner dependent on EBF1's C-terminal domain (CTD) and independent of cooperating transcription factors. Here, we studied the mechanism whereby the CTD enables this pioneering function. The CTD of EBF1 was dispensable for initial chromatin targeting but stabilized occupancy via recruitment of the chromatin remodeler Brg1. We found that the CTD harbors a prion-like domain (PLD) with an ability of liquid-liquid phase separation, which was enhanced by interaction of EBF1 with the RNA-binding protein FUS. Brg1 also partitioned into phase-separated FUS condensates and coincided with EBF1 and FUS foci in pro-B cells. Heterologous PLDs conferred pioneering function on EBF1ΔCTD. Thus, the phase separation ability of EBF1 facilitates Brg1-mediated chromatin opening and the transition of naive progenitor chromatin to B-lineage-committed chromatin.


Subject(s)
B-Lymphocytes/metabolism , Chromatin/metabolism , Prions/chemistry , Trans-Activators/metabolism , Amino Acid Sequence , B-Lymphocytes/cytology , DNA Helicases/metabolism , Humans , Nuclear Proteins/metabolism , Phase Transition , Precursor Cells, B-Lymphoid/cytology , Precursor Cells, B-Lymphoid/metabolism , Protein Domains , RNA-Binding Protein FUS/metabolism , RNA-Binding Proteins/metabolism , Trans-Activators/chemistry , Transcription Factors/metabolism
5.
RSC Adv ; 10(27): 15846-15852, 2020 Apr 21.
Article in English | MEDLINE | ID: mdl-35493675

ABSTRACT

In this study, hierarchically mesoporous silica (HMS) with properties such as high specific surface area, high photostability, and no cellular toxicity was synthesized. The synthesized silica can be considered as an excellent carrier candidate material. Through the use of nitrogen adsorption and desorption analysis, the shape of the hysteresis loop implied the presence of mesoporous structures in the HMS powder. In addition, the encapsulation efficiency was more than 90%. These results showed that avobenzone could be encapsulated into the HMS powder because of its high specific surface area and pore volume. Additionally, X-ray diffractometry (XRD), Fourier transform infrared spectroscopy (FTIR), thermal gravimetric analysis (TGA), and UV-visible (Vis) spectrophotometry were used to prove that the hierarchically mesoporous silica was able to effectively encapsulate avobenzone. In addition, the new synthetic sunscreen kept its excellent UVA absorption properties after being encapsulated.

6.
RSC Adv ; 8(36): 20319-20326, 2018 May 30.
Article in English | MEDLINE | ID: mdl-35541691

ABSTRACT

Na3V2(PO4)3 (NVP) is regarded as a promising cathode material for sustainable energy storage applications. Here we present an efficient method to synthesize off-stoichiometric Na3-3x V2+x (PO4)3/C (x = 0-0.10) nanocomposites with excellent high-rate and long-life performance for sodium-ion batteries by high-energy ball milling. It is found that Na3-3x V2+x (PO4)3/C nanocomposites with x = 0.05 (NVP-0.05) exhibit the most excellent performance. When cycled at a rate of 1C in the range of 2.3-3.9 V, the initial discharge capacity of NVP-0.05 is 112.4 mA h g-1, which is about 96% of its theoretical value (117.6 mA h g-1). Even at 20C, it still delivers a discharge capacity of 92.3 mA h g-1 (79% of the theoretical capacity). The specific capacity of NVP-0.05 is as high as 100.7 mA h g-1 after 500 cycles at 5C, which maintains 95% of its initial value (106 mA h g-1). The significantly improved electrochemical performance of NVP-0.05 is attributed to the decrease of internal resistance and increase of the Na+ ion diffusion coefficient.

7.
EMBO Rep ; 18(2): 205-216, 2017 02.
Article in English | MEDLINE | ID: mdl-28073917

ABSTRACT

The functional role of the ubiquitin-proteasome pathway during maternal-to-zygotic transition (MZT) remains to be elucidated. Here we show that the E3 ubiquitin ligase, Rnf114, is highly expressed in mouse oocytes and that knockdown of Rnf114 inhibits development beyond the two-cell stage. To study the underlying mechanism, we identify its candidate substrates using a 9,000-protein microarray and validate them using an in vitro ubiquitination system. We show that five substrates could be degraded by RNF114-mediated ubiquitination, including TAB1. Furthermore, the degradation of TAB1 in mouse early embryos is required for MZT, most likely because it activates the NF-κB pathway. Taken together, our study uncovers that RNF114-mediated ubiquitination and degradation of TAB1 activate the NF-κB pathway during MZT, and thus directly link maternal clearance to early embryo development.


Subject(s)
Adaptor Proteins, Signal Transducing/metabolism , Maternal Inheritance , Ubiquitin-Protein Ligases/metabolism , Zygote/metabolism , Adaptor Proteins, Signal Transducing/genetics , Animals , Cluster Analysis , Embryonic Development/genetics , Female , Gene Expression Profiling , Gene Expression Regulation, Developmental , Gene Knockdown Techniques , Mice , NF-kappa B/metabolism , Oocytes/metabolism , Polyubiquitin/metabolism , Proteolysis , Signal Transduction , Substrate Specificity , Ubiquitin-Protein Ligases/genetics
8.
Nucleic Acids Res ; 44(20): 9681-9697, 2016 Nov 16.
Article in English | MEDLINE | ID: mdl-27431324

ABSTRACT

Meiotic recombination is essential for fertility in most sexually reproducing species, but the molecular mechanisms underlying this process remain poorly understood in mammals. Here, we show that RNF20-mediated H2B ubiquitination is required for meiotic recombination. A germ cell-specific knockout of the H2B ubiquitination E3 ligase RNF20 results in complete male infertility. The Stra8-Rnf20-/- spermatocytes arrest at the pachytene stage because of impaired programmed double-strand break (DSB) repair. Further investigations reveal that the depletion of RNF20 in the germ cells affects chromatin relaxation, thus preventing programmed DSB repair factors from being recruited to proper positions on the chromatin. The gametogenetic defects of the H2B ubiquitination deficient cells could be partially rescued by forced chromatin relaxation. Taken together, our results demonstrate that RNF20/Bre1p-mediated H2B ubiquitination regulates meiotic recombination by promoting chromatin relaxation, and suggest an old drug may provide a new way to treat some oligo- or azoospermia patients with chromatin relaxation disorders.


Subject(s)
Chromatin Assembly and Disassembly , Chromatin/genetics , Chromatin/metabolism , Histones/metabolism , Meiosis , Recombination, Genetic , Adaptor Proteins, Signal Transducing/deficiency , Animals , DNA Breaks, Double-Stranded , DNA Repair , Female , Germ Cells/metabolism , Infertility, Male/genetics , Male , Mice , Mice, Knockout , Pachytene Stage/genetics , Spermatocytes/metabolism , Spermatogenesis/genetics , Ubiquitin-Protein Ligases/deficiency , Ubiquitination
9.
Autophagy ; 12(4): 671-88, 2016.
Article in English | MEDLINE | ID: mdl-27050457

ABSTRACT

Meiosis is a special type of cellular renovation that involves 2 successive cell divisions and a single round of DNA replication. Two major degradation systems, the autophagy-lysosome and the ubiquitin-proteasome, are involved in meiosis, but their roles have yet to be elucidated. Here we show that autophagy mainly affects the initiation of meiosis but not the nuclear division. Autophagy works not only by serving as a dynamic recycling system but also by eliminating some negative meiotic regulators such as Ego4 (Ynr034w-a). In a quantitative proteomics study, the proteasome was found to be significantly upregulated during meiotic divisions. We found that proteasomal activity is essential to the 2 successive meiotic nuclear divisions but not for the initiation of meiosis. Our study defines the roles of autophagy and the proteasome in meiosis: Autophagy mainly affects the initiation of meiosis, whereas the proteasome mainly affects the 2 successive meiotic divisions.


Subject(s)
Autophagy , Meiosis , Proteasome Endopeptidase Complex/metabolism , Saccharomyces cerevisiae/cytology , Saccharomyces cerevisiae/metabolism , DNA Replication , Down-Regulation , Pachytene Stage , Prophase , Protein Binding , Proteomics , Reproducibility of Results , Ribosomes/metabolism , Saccharomyces cerevisiae Proteins/metabolism , Time Factors
10.
Adv Mater ; 28(17): 3290-7, 2016 05.
Article in English | MEDLINE | ID: mdl-26928274

ABSTRACT

UNLABELLED: The successful application of a Ni/Au transparent electrode for fabricating efficient perovskite-based solar cells is demonstrated. Through interdiffusion of the Ni/Au bilayer, Au forms an interconnected metallic network structure as the transparent electrode. Ni diffuses to the bilayer surface and oxidizes into NiOx becoming an appropriate electrode interlayer. These ITO- and PEDOT: PSS-free devices have potential applications in the design of future cost-effective, low-weight, and stable solar cells.

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