NF-Y Recruits Ash2L to Impart H3K4 Trimethylation on CCAAT Promoters

BACKGROUND: Different histone post-translational modifications (PTMs) are crucial in the regulation of chromatin, including methylations of H3 at Lysine 4 by the MLL complex. A relevant issue is how this is causally correlated to the binding of specific transcription factors (TFs) in regulatory regions. NF-Y is a TF that regulates 30% of mammalian promoters containing the widespread CCAAT element. We and others established that the presence of H3K4me3 is dependent upon the binding of NF-Y. Here, we investigate the mechanisms of H3K4me3 deposition by NF-Y. METHODS: We employed Chromatin Immunoprecipitation in cells in which Ash2L and NF-Y subunits were knocked down by RNAi, to monitor the presence of histones PTMs and components of the MLL complex. We performed gene expression profiling of Ash2L-knocked down cells and analyzed the regulated genes. We performed ChIPs in leukemic cells in which MLL1 is devoid of the methyltransferase domain and fused to the AF4 gene. RESULTS: Knock down of the Ash2L subunit of MLL leads to a decrease in global H3K4me3 with a concomitant increase in H3K79me2. Knock down of NF-Y subunits prevents promoter association of Ash2L, but not MLL1, nor WDR5, and H3K4me3 drops dramatically. Endogenous NF-Y and Ash2L specifically interact in vivo. Analysis of the promoters of Ash2L regulated genes, identified by transcriptional profiling, suggests that a handful TF binding sites are moderately enriched, among which the CCAAT box. Finally, leukemic cells carrying the MLL-AF4 translocation show a decrease of H3K4me3, absence of Ash2L and increase in H3K79me2, while NF-Y binding was not significantly affected. CONCLUSIONS: Three types of conclusions are reached: (i) H3K4 methylation is not absolutely required for NF-Y promoter association. (ii) NF-Y acts upstream of H3K4me3 deposition by recruiting Ash2L. (iii) There is a general cross-talk between H3K4me3 and H3K79me2 which is independent from the presence of MLL oncogenic fusions

Enhanced control of self-doping in halide perovskites for improved thermoelectric performance

Metal halide perovskites have emerged as promising photovoltaic materials, but, despite ultralow thermal conductivity, progress on developing them for thermoelectrics has been limited. Here, we report the thermoelectric properties of all-inorganic tin based perovskites with enhanced air stability. Fine tuning the thermoelectric properties of the films is achieved by self-doping through the oxidation of tin (ΙΙ) to tin (ΙV) in a thin surface-layer that transfers charge to the bulk. This separates the doping defects from the transport region, enabling enhanced electrical conductivity. We show that this arises due to a chlorine-rich surface layer that acts simultaneously as the source of free charges and a sacrificial layer protecting the bulk from oxidation. Moreover, we achieve a figure-of-merit (ZT) of 0.14 ± 0.01 when chlorine-doping and degree of the oxidation are optimised in tandem

Herbal Medicines for Parkinson's Disease: A Systematic Review of Randomized Controlled Trials

OBJECTIVE: We conducted systematic review to evaluate current evidence of herbal medicines (HMs) for Parkinson's disease (PD). METHODS: Along with hand searches, relevant literatures were located from the electronic databases including CENTRAL, MEDLINE, EMBASE, CINAHL, AMED, PsycInfo, CNKI, 7 Korean Medical Databases and J-East until August, 2010 without language and publication status. Randomized controlled trials (RCTs), quasi-randomized controlled trials and randomized crossover trials, which evaluate HMs for idiopathic PD were selected for this review. Two independent authors extracted data from the relevant literatures and any disagreement was solved by discussion. RESULTS: From the 3432 of relevant literatures, 64 were included. We failed to suggest overall estimates of treatment effects on PD because of the wide heterogeneity of used herbal recipes and study designs in the included studies. When compared with placebo, specific effects were not observed in favor of HMs definitely. Direct comparison with conventional drugs suggested that there was no evidence of better effect for HMs. Many studies compared combination therapy with single active drugs and combination therapy showed significant improvement in PD related outcomes and decrease in the dose of anti-Parkinson's drugs with low adverse events rate. CONCLUSION: Currently, there is no conclusive evidence about the effectiveness and efficacy of HMs on PD. For establishing clinical evidence of HMs on PD, rigorous RCTs with sufficient statistical power should be promoted in future

The disruption of proteostasis in neurodegenerative diseases

Cells count on surveillance systems to monitor and protect the cellular proteome which, besides being highly heterogeneous, is constantly being challenged by intrinsic and environmental factors. In this context, the proteostasis network (PN) is essential to achieve a stable and functional proteome. Disruption of the PN is associated with aging and can lead to and/or potentiate the occurrence of many neurodegenerative diseases (ND). This not only emphasizes the importance of the PN in health span and aging but also how its modulation can be a potential target for intervention and treatment of human diseases.info:eu-repo/semantics/publishedVersio

Enhancement of ionic conductivity of PEO based polymer electrolyte by the addition of nanosize ceramic powders

The ionic conductivity of polyethylene oxide (PEO) based solid polymer electrolytes (SPEs) has been improved by the addition of nanosize ceramic powders (TiO 2 and Al 2O 3). The PEO based solid polymer electrolytes were prepared by the solution-casting method. Electrochemical measurement shows that the 10 wt% TiO 2 PEO-LiClO 4 polymer electrolyte has the best ionic conductivity (about 10 -4 S cm -1 at 40-60°C). The lithium transference number of the 10 wt% TiO 2 PEO-LiClO 4 polymer electrolyte was measured to be 0.47, which is much higher than that of bare PEO polymer electrolyte. Ac impedance testing shows that the interface resistance of ceramic-added PEO polymer electrolyte is stable. Linear sweep voltammetry measurement shows that the PEO polymer electrolytes are electrochemically stable in the voltage range of 2.0-5.0 V versus a Li/Li + reference electrode. Copyright © 2005 American Scientific Publishers All rights reserved

Enhanced reversible lithium storage in a nanosize silicon/graphene composite.

Si/graphene composite was prepared by simply mixing of commercially available nanosize Si and graphene. Electrochemical tests show that the Si/graphene composite maintains a capacity of 1168 mAh g−1 and an average coulombic efficiency of 93% up to 30 cycles. EIS indicates that the Si/graphene composite electrode has less than 50% of the charge-transfer resistance compared with nanosize Si electrode, evidencing the enhanced ionic conductivity of Si/graphene composite. The enhanced cycling stability is attributed to the fact that the Si/graphene composite can accommodate large volume charge of Si and maintain good electronic contact. © 2010, Elsevier Ltd

Electron Delocalization and Dissolution-Restraint in Vanadium Oxide Superlattices to Boost Electrochemical Performance of Aqueous Zinc-Ion Batteries

© 2020 Wiley-VCH GmbH Aqueous zinc-ion batteries (ZIBs) have triggered a great deal of scientific research and become a promising alternative for large-scale energy storage applications, owing to the unique merits of high volumetric energy density, abundance of zinc resources, eco-friendliness, and safety. The pace of progress of ZIB development, however, is hindered by their poor reversibility and sluggish kinetics, derived from the dissolution of active materials in aqueous electrolytes and the strong electrostatic interactions between Zn2+ and the cathode lattice. Herein, a vanadium oxide (V2O5-x)/polyaniline (PANI-V) superlattice structure is demonstrated as a model of superlattice structural engineering to overcome these weaknesses. In this superlattice, the PANI layer not only plays the role of a spacer to expand the V2O5-x interlayer spacing but also serves as a conductive capacity contributor. Moreover, the PANI layer servers as structural stabilizer to restrain the dissolution of V2O5-x active materials in aqueous electrolytes. In addition, it introduces an interface effect to modulate the charge distribution of the V2O5-x monolayer, promoting Zn-ion diffusion into the structure. Correspondingly, weakening the electrostatic interactions and supressing the active materials dissolution synergistically boosts the electrochemical performance for Zn-ion storage. This work paves the way for the development/improvement of cathodes for aqueous zinc-ion batteries

Nanostructured electrode materials for rechargeable lithium-ion battery applications

Nanocrystalline LiFePO4 and Si-C powders were prepared as electrode materials for lithium-ion batteries. Near full capacity (170 mAh/g) was achieved at the C/8 rate at room temperature for LiFePO4 electrodes. Nanosize Si-C composite anode materials demonstrated a reversible lithium storage capacity of 1450 mAh/g with good cyclability when used as anodes in lithium-ion cells. Nanostructured electrode materials have an important role to play in developing a new generation of lithium-ion batteries that will offer a dramatic improvement in power delivery