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Background: The drug delivery vehicle 2-hydroxypropyl-β-cyclodextrin (HPβCD) prevents cholesterol storage. Results: HPβCD treatment induces TFEB mediated activation of autophagy and clearance of the autophagic substrate ceroid lipopigment. Conclusion: HPβCD administration results in enhancement of the innate autophagic clearance capacity. Significance: Dissecting the cellular pathways impacted by HPβCD is crucial to design HPβCD-based therapeutic modalities. 2-Hydroxypropyl-β-cyclodextrin (HPβCD) is a Food and Drug Administration-approved excipient used to improve the stability and bioavailability of drugs. Despite its wide use as a drug delivery vehicle and the recent approval of a clinical trial to evaluate its potential for the treatment of a cholesterol storage disorder, the cellular pathways involved in the adaptive response that is activated upon exposure to HPβCD are still poorly defined. Here, we show that cell treatment with HPβCD results in the activation of the transcription factor EB, a master regulator of lysosomal function and autophagy, and in enhancement of the cellular autophagic clearance capacity. HPβCD administration promotes transcription factor EB-mediated clearance of proteolipid aggregates that accumulate due to inefficient activity of the lysosome-autophagy system in cells derived from a patient with a lysosomal storage disorder. Interestingly, HPβCD-mediated activation of autophagy was found not to be associated with activation of apoptotic pathways. This study provides a mechanistic understanding of the cellular response to HPβCD treatment, which will inform the development of safe HPβCD-based therapeutic modalities and may enable engineering HPβCD as a platform technology to reduce the accumulation of lysosomal storage material. [ABSTRACT FROM AUTHOR]

TDP-43 is a highly conserved, 43-kDa RNA-binding protein implicated to play a role in transcription repression, nuclear organization, and alternative splicing. More recently, this factor has been identified as the major disease protein of several neurodegenerative diseases, including frontotemporal lobar degeneration with ubiquitin-positive inclusions and amyotrophic lateral sclerosis. For the splicing activity, the factor has been shown to be mainly an exon-skipping promoter. In this study using the survival of motor neuron (SMN) minigenes as the reporters in transfection assay, we show for the first time that TDP-43 could also act as an exon-inclusion factor. Furthermore, both RNA-recognition motif domains are required for its ability to enhance the SMN2 exon 7 inclusion. Combined protein-immunoprecipitation and RNA-immunoprecipitation experiments also suggested that this exon inclusion activity might be mediated by multimeric complex(es) consisting of this protein interacting with other splicing factors, including Htra2-β1. Our data further evidence TDP-43 as a multifunctional RNA-binding protein for a diverse set of cellular activities. [ABSTRACT FROM AUTHOR]

A bio-inspired nanofibrous Co 3 O 4 /TiO 2 /carbon composite was fabricated using natural cellulose substrate (laboratory filter paper) as both the carbon source and the structural scaffold. Employing a surface sol–gel process to form a thin TiO 2 gel layer coating on each cellulose nanofiber of the filter paper, the resulted composite sheet was successively carbonized in inert atmosphere to give a nanofibrous TiO 2 /carbon composite; afterwards, nano-sized Co 3 O 4 particles (10–30 nm) were uniformly deposited onto the yielded composite fibers via a simple hydrothermal method, resulting in the Co 3 O 4 /TiO 2 /carbon hybrid. The ternary composite possessed a unique hierarchically three-dimensional porous structure which inherited precisely from the initial filter paper. This special structure with the internal conductive carbon fiber and the external nano-sized Co 3 O 4 particles offered the nanocomposite with an excellent electrochemical performance as anodic material for lithium-ion batteries. The optimal sample with a Co 3 O 4 mass content of 50.6% delivered an initial discharge capacity of 1239 mAh g−1 at a current density of 100 mA g−1, which was far exceeded the theoretical capacity of Co 3 O 4. The extra capacity is ascribed to the additional lithium storage sites provided by the large specific surface area of the composite, and the formation of the solid electrolyte interface (SEI) layer in the initial discharge process causing a large consumption of Li+ which results in some irreversible capacity. And after 200 discharge/charge cycles, a high reversible capacity of 764 mAh g−1 was maintained, which is higher than most of the Co 3 O 4 /carbon hybrid materials reported. This work provided a simple and efficient strategy for designing and preparing nanoscale metal-oxide/carbon composite material with considerable potential in energy storage and conversion. Nanofibrous Co 3 O 4 /TiO 2 /carbon composite derived from cellulose substance was fabricated, showing enhanced electrochemical performances as an anodic material for lithium-ion batteries. Image 1 • A cellulose derived nanofibrous Co 3 O 4 /TiO 2 /carbon composite was fabricated. • Nanosized Co 3 O 4 particles were coated uniformly on the nanofiber surfaces. • The composite possessed a unique hierarchically porous net work structure. • It exhibited superior electrochemical performances as anodic material for LIBs. [ABSTRACT FROM AUTHOR]

NiCrAl–WC–Ti 3 SiC 2 composite coatings with the different Ti 3 SiC 2 mass fractions were prepared on H13 steel by laser cladding (LC). The influence of Ti 3 SiC 2 mass fraction on the tribological property of obtained composite coatings at 500 °C was investigated using a high temperature wear machine, and the roles of WC and Ti 3 SiC 2 in the friction process were discussed in detail. The results show that the coefficients of friction (COFs) and wear rates of NiCrAl–WC–Ti 3 SiC 2 composite coatings are increased with the Ti 3 SiC 2 mass fraction, exhibiting the appropriate Ti 3 SiC 2 mass fraction plays a certain role in the friction reduction and wear resistance, which are contributed to the coarsening of grains and the decrease of hardness. In addition, it is also found that the Ti 3 SiC 2 is reacted with the WC to generate SiC, TiC, TiWC 2 and other hard phases, and the amount of WC particles of coatings is decreased by the addition of Ti 3 SiC 2 , which is the main factor for the decline of tribological performance. [Display omitted] • The TiWC 2 , SiC and TiC phases are generated by the reactions between the Ti 3 SiC 2 and the WC. • The grains of NiCrAl-WC-Ti 3 SiC 2 coatings become coarser with Ti 3 SiC 2 mass fraction. • The NiCrAl-40%WC-3%Ti 3 SiC 2 coating has the best tribological property. • The wear mechanism of NiCrAl-WC-Ti 3 SiC 2 coatings is adhesive, abrasive and oxidation wear. [ABSTRACT FROM AUTHOR]

Coronary artery disease (CAD) is the leading cause of death worldwide. Long noncoding RNAs (lncRNAs) are a class of noncoding transcripts of > 200 nucleotides and are increasingly recognized as playing functional roles in physiology and disease. ANRIL is a lncRNA gene mapped to the chromosome 9p21 genetic locus for CAD identified by the first series of genome-wide association studies (GWAS). However, ANRIL's role in CAD and the underlying molecular mechanism are unknown. Here, we show that the major ANRIL transcript in endothelial cells (ECs) is DQ485454 with a much higher expression level in ECs than in THP-1 monocytes. Of note, DQ485454 expression was down-regulated in CAD coronary arteries compared with non-CAD arteries. DQ485454 overexpression significantly reduced monocyte adhesion to ECs, transendothelial monocyte migration (TEM), and EC migration, which are critical cellular processes involved in CAD initiation, whereas siRNA-mediated ANRIL knockdown (KD) had the opposite effect. Microarray and follow-up quantitative RT-PCR analyses revealed that the ANRIL KD down-regulated expression of AHNAK2, CLIP1, CXCL11, ENC1, EZR, LYVE1, WASL, and TNFSF10 genes, and up-regulated TMEM100 and TMEM106B genes. Mechanistic studies disclosed that overexpression of CLIP1, EZR, and LYVE1 reversed the effects of ANRIL KD on monocyte adhesion to ECs, TEM, and EC migration. These findings indicate that ANRIL regulates EC functions directly related to CAD, supporting the hypothesis that ANRIL is involved in CAD pathogenesis at the 9p21 genetic locus and identifying a molecular mechanism underlying lncRNA-mediated regulation of EC function and CAD development. [ABSTRACT FROM AUTHOR]

Nav1.5 is the α-subunit of the cardiac sodium channel complex. Abnormal expression of Nav1.5 on the cell surface because of mutations that disrupt Nav1.5 trafficking causes Brugada syndrome (BrS), sick sinus syndrome (SSS), cardiac conduction disease, dilated cardiomyopathy, and sudden infant death syndrome. We and others previously reported that Ran-binding protein MOG1 (MOG1), a small protein that interacts with Nav1.5, promotes Nav1.5 intracellular trafficking to plasma membranes and that a substitution in MOG1, E83D, causes BrS. However, the molecular basis for the MOG1/Nav1.5 interaction and how the E83D substitution causes BrS remains unknown. Here, we assessed the effects of defined MOG1 deletions and alanine-scanning substitutions on MOG1's interaction with Nav1.5. Large deletion analysis mapped the MOG1 domain required for the interaction with Nav1.5 to the region spanning amino acids 146-174, and a refined deletion analysis further narrowed this domain to amino acids 146-155. Site-directed mutagenesis further revealed that Asp-148, Arg-150, and Ser-151 cluster in a peptide loop essential for binding toNav1.5.GST pulldown and electrophysiological analyses disclosed that the substitutions E83D, D148Q, R150Q, and S151Q disrupt MOG1's interaction with Nav1.5 and significantly reduce its trafficking to the cell surface. Examination of MOG1's 3D structure revealed that Glu-83 and the loop containing Asp-148, Arg-150, and Ser-151 are spatially proximal, suggesting that these residues form a critical binding site for Nav1.5. In conclusion, our findings identify the structural elements in MOG1 that are crucial for its interaction with Nav1.5 and improve our understanding of how the E83D substitution causes BrS. [ABSTRACT FROM AUTHOR]

The nuclear factor κB (NF-κB) transcription factor family regulates genes involved in cell proliferation and inflammation. The promoters of these genes often contain NF-κBbinding sites (κB sites) arranged in tandem. How NF-κB activates transcription through these multiple sites is incompletely understood. We report here an X-ray crystal structure of homodimers comprising the RelA DNA-binding domain containing the Rel homology region (RHR) in NF-κB bound to an E-selectin promoter fragment with tandem κB sites. This structure revealed that two dimers bind asymmetrically to the symmetrically arranged κB sites at which multiple cognate contacts between one dimer to the corresponding DNA are broken. Because simultaneous RelA-RHR dimer binding to tandem sites in solution was anti-cooperative, we inferred that asymmetric RelA-RHR binding with fewer contacts likely indicates a dissociative binding mode. We found that both κB sites are essential for reporter gene activation by full-length RelA homodimer, suggesting that dimers facilitate DNA binding to each other even though their stable cooccupation is not promoted. Promoter variants with altered spacing and orientation of tandem κB sites displayed unexpected reporter activities that were not explained by the solution- binding pattern of RelA-RHR. Remarkably, full-length RelA bound all DNAs with a weaker affinity and specificity. Moreover, the transactivation domain played a negative role in DNA binding. These observations suggest that other nuclear factors influence full-length RelA binding toDNAby neutralizing the transactivation domain negative effect. We propose that DNA binding by NF-κB dimers is highly complex and modulated by facilitated association-dissociation processes. [ABSTRACT FROM AUTHOR]

Targeted inhibitors of the human epidermal growth factor receptor 2 (HER2), such as trastuzumab and lapatinib, are among the first examples of molecularly targeted cancer therapy and have proven largely effective for the treatment of HER2-positive breast cancers. However, approximately half of those patients either do not respond to these therapies or develop secondary resistance. Although a few signaling pathways have been implicated, a comprehensive understanding of mechanisms underlying HER2 inhibitor drug resistance is still lacking. To address this critical question, we undertook a concerted approach using patient expression data sets, HER2-positive cell lines, and tumor samples biopsied both before and after trastuzumab treatment. Together, these methods revealed that high expression and activation of a specific subset of receptor tyrosine kinases (RTKs) was strongly associated with poor clinical prognosis and the development of resistance. Mechanistically, these RTKs are capable of maintaining downstream signal transduction to promote tumor growth via the suppression of cellular senescence. Consequently, these findings provide the rationale for the design of therapeutic strategies for overcoming drug resistance in breast cancer via combinational inhibition of the limited number of targets from this specific subset of RTKs. [ABSTRACT FROM AUTHOR]

Once it enters the host cell, herpes simplex virus type 1 (HSV-1) recruits a series of host cell factors to facilitate its life cycle. Here, we demonstrate that serine/arginine-rich splicing factor 2 (SRSF2), which is an important component of the splicing speckle, mediates HSV-1 replication by regulating viral gene expression at the transcriptional and posttranscriptional levels. Our results indicate that SRSF2 functions as a transcriptional activator by directly binding to infected cell polypeptide 0 (ICP0), infected cell polypeptide 27 (ICP27), and thymidine kinase promoters. Moreover, SRSF2 participates in ICP0 pre-mRNA splicing by recognizing binding sites in ICP0 exon 3. These findings provide insight into the functions of SRSF2 in HSV-1 replication and gene expression. [ABSTRACT FROM AUTHOR]

To explore the interactions among immunity related genes and the risk of breast cancer (BC), 376 invasive ductal carcinoma (IDC) of the breast cases and 366 healthy controls were selected into our study. Twenty single nucleotide polymorphisms (SNPs) of five immunological genes in the CD28/B7 pathway were genotyped. Overall, five SNPs filtered by the Relief F algorithm were rs733618, rs11889031, rs4553808, rs4675374 and rs10754339. The best model of multifactor dimensionality reduction (MDR) contained rs733618 and rs11889031. The high risk genotype combination contributed to increasing risk of breast cancer (odds ratio (OR), 4.36; 95% confidence interval (CI); 3.15–6.02). The information gain (IG) value of these two SNPs was 8.07%, presented the strongest interaction effect. Five significant multiplicative interactions and seven significant combining effects were found among the filtered SNPs. Moreover, the filtered SNPs were still stable in the groups of ER(+), PR(+), CerbB2(−) and lymph node (LN) involvement positive with the best models including rs733618 and rs11889031. The most frequent haplotype was TACC which significantly increased breast cancer risk (OR, 1.80; 95% CI, 1.43–2.25). These results suggested that interactions among cytotoxic T lymphocyte antigen-4 ( CTLA4 ), inducible co-stimulator ( ICOS ) and B7H4 might play critical roles on the risk of breast cancer. [ABSTRACT FROM AUTHOR]

• In In ZnGa2O4:Cr3+ system, Cr3+-doping and Cr-O bond distort the local lattice and change the crystal field • Cr3+-doping narrows the real optical band gap of ZnGa2O4:Cr3+ system and shifts its absorption edge. • Cr3+-doping increase the static dielectric constant of ZnGa2O4:Cr3+ material system. ZnGa 2 O 4 is an important cathodoluminescent material which exhibits good near-infrared long afterglow characteristics after being Cr-doped into Ga sites (ZGO: Cr). The band structure, crystal structure and optical properties of ZGO: Cr are investigated by using first-principles calculations based on density functional theory. It is found that, in the ZGO: Cr system, due to the presence of the Cr-O bond, the distortion of the local lattice goes up as the Cr3+ doping amount increases. Meanwhile, impurity levels appear near the Fermi level of the ZGO system, and the orbital controlling the conduction band bottom gradually moves from the Ga-4s orbital to the Cr-3d orbital. Consequently, the real optical band-gap of the ZGO: Cr system becomes narrower, and the absorption edge undergoes a red-shift. The density of states of all upward and downward atomic spins is distributed asymmetrically, indicating that ZGO: Cr exhibits a certain amount of spin polarization. Additionally, the static dielectric constant of the ZGO: Cr material system increases with the increase in the Cr3+ doping amount. According to the findings, adjustments can be made of the doping concentration and energy range in the optical applications of ZGO: Cr material system. [ABSTRACT FROM AUTHOR]

Brain-selective kinase 2 (BRSK2) has been shown to play an essential role in neuronal polarization. In the present study, we show that BRSK2 is also abundantly expressed in pancreatic islets and MIN6 β-cell line. Yeast two-hybrid screening, GST fusion protein pull-down, and co-immunoprecipitation assays reveal that BRSK2 interacts with CDK-related protein kinase PCTAIRE1, a kinase involved in neurite outgrowth and neurotransmitter release. In MIN6 cells, BRSK2 co-localizes with PCTAIRE1 in the cytoplasm and phosphorylates one of its serine residues, Ser-12. Phosphorylation of PCTAIRE1 by BRSK2 reduces glucose-stimulated insulin secretion (GSIS) in MIN6 cells. Conversely, knockdown of BRSK2 by siRNA increases serum insulin levels in mice. Our results reveal a novel function of BRSK2 in the regulation of GSIS in β-cells via a PCTAIRE1- dependent mechanism and suggest that BRSK2 is an attractive target for developing novel diabetic drugs. [ABSTRACT FROM AUTHOR]

Unlike neurons in the central nervous system (CNS), injured neurons in the peripheral nervous system (PNS) can regenerate their axons and reinnervate their targets. However, functional recovery in the PNS often remains suboptimal, especially in cases of severe damage. The lack of regenerative ability of CNS neurons has been linked to down-regulation of the mTOR (mammalian target of rapamycin) pathway. We report here that PNS dorsal root ganglial neurons (DRGs) activate mTOR following damage and that this activity enhances axonal growth capacity. Furthermore, genetic up-regulation of mTOR activity by deletion of tuberous sclerosis complex 2 (TSC2) in DRGs is sufficient to enhance axonal growth capacity in vitro and in vivo. We further show that mTOR activity is linked to the expression of GAP-43, a crucial component of axonal outgrowth. However, although TSC2 deletion in DRGs facilitates axonal regrowth, it leads to defects in target innervation. Thus, whereas manipulation of mTOR activity could provide new strategies to stimulate nerve regeneration in the PNS, fine control of mTOR activity is required for proper target innervation. [ABSTRACT FROM AUTHOR]

NDRG4 is a largely unstudied member of the predominantly tumor suppressive N-Myc downstream-regulated gene (NDRG) family. Unlike its family members NDRG1-3, which are ubiquitously expressed, NDRG4 is expressed almost exclusively in the heart and brain. Given this tissue-specific expression pattern and the established tumor suppressive roles of the NDRG family in regulating cellular proliferation, we investigated the cellular and biochemical functions of NDRG4 in the context of astrocytes and glioblastoma multiforme (GBM) cells. We show that, in contrast to NDRG2, NDRG4 expression is elevated in GBM and NDRG4 is required for the viability of primary astrocytes, established GBM cell lines, and both CD133+ (cancer stem cell (CSC)-enriched) and CD133- primary GBM xenograft cells. While NDRG4 overexpression has no effect on cell viability, NDRG4 knockdown causes G1 cell cycle arrest followed by apoptosis. The initial G1 arrest is associated with a decrease in cyclin Dl expression and an increase in p27Kip1 expression, and the subsequent apoptosis is associated with a decrease in the expression of XIAP and survivin. As a result of these effects on cell cycle progression and survival, NDRG4 knockdown decreases the tumorigenic capacity of established GBM cell lines and GBM CSC-enriched cells that have been implanted intracranially into immunocompromised mice. Collectively, these data indicate that NDRG4 is required for cell cycle progression and survival, thereby diverging in function from its tumor suppressive family member NDRG2 in astrocytes and GBM cells. [ABSTRACT FROM AUTHOR]

Abstract: Rich silver-bearing low-grade complex sulfide ores can be found in great supply in China''s Yunnan Province. The beneficiation experiment showed that it would be very difficult to separate Ag (Zn or Pb) minerals with traditional ore beneficiation methods. In the present work, acid pressure oxidative leaching of such complex sulfide ores in sulfate medium added sodium iodine and at the temperature ranging from 90 to 170 °C was studied to search for silver recovery alternatives. The Lab-scale experiments were conducted in a 2-L autoclave to investigate the influences of temperature, acidity, sodium iodide addition, oxygen pressure, oxygen flow rate on recovery of silver and zinc. The experimental results obtained show that under optimum conditions, recovery yield of silver and zinc reaches 71.5% and 41.29%, respectively. [Copyright &y& Elsevier]

Secreted protein acidic, rich in cysteine (SPARC), is an extracellular matrix protein expressed in many advanced cancers, including malignant gliomas. We and others have previously shown that human glioma cell lines engineered to overexpress SPARC adopt an invasive phenotype. We now show that SPARC expression increases cell survival under stress initiated by serum withdrawal through a decrease in apoptosis. Phosphatidylinositol 3-OH kinase/AKT is a potent pro-survival pathway that contributes to the malignancy of gliomas. Cells expressing SPARC display increased AKT activation with decreased caspase 3/7 activity. Exogenous SPARC rapidly induces AKT phosphorylation, an effect that is blocked by a neutralizing SPARC antibody. Furthermore, AKT activation is essential for the anti-apoptotic effects of SPARC as the decreased apoptosis and caspase activity associated with SPARC expression can be blocked with dominant-negative AKT or a specific AKT inhibitor. As tumor cells face stressful microenvironments particularly during the process of invasion, these results suggest that SPARC functions, in part, to promote tumor progression by enabling tumor cells to survive under stressful conditions. [ABSTRACT FROM AUTHOR]

The transforming growth factor-β (TGF-β) signaling pathway is known to be involved in a wide range of biological events, including development, cellular differentiation, apoptosis, and oncogenesis. The TGF-β signal is mediated by ligand binding to the type II receptor, leading to the recruitment and activation of the type I receptor, and subsequent activation of a family of intracellular signal transducing proteins called Smads. Here we report a regulatory role for casein kinase I∈ (CKI∈) in the TGF-β signaling cascade. We find that CKI∈ binds to all Smads and the cytoplasmic domains of the type I and type II receptors both in vitro and in vivo. The interaction of CKI∈ with the type I and type II receptors is independent of TGF-β stimulation, whereas the CKI∈/ Smad interaction is transiently disrupted by ligand treatment. Additionally, CKI∈ is able to phosphorylate the receptor-activated Smads (Smads 1-3 and 5) and the type II receptor in vitro. Transcriptional reporter assays reveal that transient overexpression of wild type CKI∈ dramatically reduces basal reporter activity but enhances TGF-β-stimulated transcription. Furthermore, overexpression of a kinase-dead mutant of CKI∈ inhibits both basal and ligand-induced transcription, whereas inhibition of endogenous CKI catalytic activity with IC261 blocks only TGF-β-stimulated reporter activity. Finally, knocking down CKI∈ protein levels results in a significant increase in basal and TGF-β-induced transcription. These results suggest that CKI∈ plays a ligand-dependent, differential, and dual regulatory role within the TGF-β signaling pathway. [ABSTRACT FROM AUTHOR]

Activation of vascular smooth muscle cells (VSMCs) by proinflammatory cytokines is a key feature of atherosclerotic lesion formation. Transforming growth factor (TGF)-β1 is a pleiotropic growth factor that can modulate the inflammatory response in diverse cell types including VSMCs. However, the mechanisms by which TGF-β1 is able to mediate these effects remains incompletely understood. We demonstrate here that the ability of TGF-β1 to inhibit markers of VSMC activation, inducible nitric-oxide synthase (iNOS) and interleukin (IL)-6, is mediated through its downstream effector Smad3. In reporter gene transfection studies, we found that among a panel of Smads, Smad3 could inhibit iNOS induction in an analogous manner as exogenous TGFβ1. Adenoviral overexpression of Smad3 potently repressed inducible expression of endogenous iNOS and IL-6. Conversely, TGF-β1 inhibition of cytokine-mediated induction of iNOS and IL-6 expression was completely blocked in Smad3-deficient VSMCs. Previous studies demonstrate that CCAAT/enhancer-binding protein (C/EBP) and NF-κB sites are critical for cytokine induction of both the iNOS and IL-6 promoters. We demonstrate that the inhibitory effect of Smad3 occurs via a novel antagonistic effect of Smad3 on C/EBP DNA-protein binding and activity. Smad3 mediates this effect in part by inhibiting C/EBP-β and C/EBP-δ through distinct mechanisms. Furthermore, we find that Smad3 prevents the cooperative induction of the iNOS promoter by C/EBP and NF-κB. These data demonstrate that Smad3 plays an essential role in mediating TGF-β1 anti-inflammatory response in VSMCs. [ABSTRACT FROM AUTHOR]

Investigates the contributions of two genes upregulated in several cancers to phenotypic changes associated with late stages of tumorigenesis. Tumor cell expressing two structurally unrelated bone-related genes, osteonectin and osteoactivin; Invasion of tumor cells into the brain along blood vessels; Creation of a complex relationship between invading tumor and vasculature.