Conservation of Helical Bundle Structure between the Exocyst Subunits

Background: The exocyst is a large hetero-octomeric protein complex required for regulating the targeting and fusion of secretory vesicles to the plasma membrane in eukaryotic cells. Although the sequence identity between the eight different exocyst subunits is less than 10%, structures of domains of four of the subunits revealed a similar helical bundle topology. Characterization of several of these subunits has been hindered by lack of soluble protein for biochemical and structural studies. Methodology/Principal Findings: Using advanced hidden Markov models combined with secondary structure predictions, we detect significant sequence similarity between each of the exocyst subunits, indicating that they all contain helical bundle structures. We corroborate these remote homology predictions by identifying and purifying a predicted domain of yeast Sec10p, a previously insoluble exocyst subunit. This domain is soluble and folded with approximately 60 % a-helicity, in agreement with our predictions, and capable of interacting with several known Sec10p binding partners. Conclusions/Significance: Although all eight of the exocyst subunits had been suggested to be composed of similar helical bundles, this has now been validated by our hidden Markov model structure predictions. In addition, these predictions identified protein domains within the exocyst subunits, resulting in creation and characterization of a soluble, folde

Intercomparison of an Aerosol Chemical Speciation Monitor (ACSM) with ambient fine aerosol measurements in downtown Atlanta, Georgia

Currently, there are a limited number of field studies that evaluate the long-term performance of the Aerodyne Aerosol Chemical Speciation Monitor (ACSM) against established monitoring networks. In this study, we present seasonal intercomparisons of the ACSM with collocated fine aerosol (PM_2.5) measurements at the Southeastern Aerosol Research and Characterization (SEARCH) Jefferson Street (JST) site near downtown Atlanta, GA, during 2011–2012. Intercomparison of two collocated ACSMs resulted in strong correlations (<i>r</i>² > 0.8) for all chemical species, except chloride (<i>r</i>² = 0.21) indicating that ACSM instruments are capable of stable and reproducible operation. In general, speciated ACSM mass concentrations correlate well (<i>r</i>² > 0.7) with the filter-adjusted continuous measurements from JST, although the correlation for nitrate is weaker (<i>r</i>² = 0.55) in summer. Correlations of the ACSM NR-PM₁ (non-refractory particulate matter with aerodynamic diameter less than or equal to 1 μm) plus elemental carbon (EC) with tapered element oscillating microbalance (TEOM) PM_2.5 and Federal Reference Method (FRM) PM₁ mass are strong with <i>r</i>² > 0.7 and <i>r</i>² > 0.8, respectively. Discrepancies might be attributed to evaporative losses of semi-volatile species from the filter measurements used to adjust the collocated continuous measurements. This suggests that adjusting the ambient aerosol continuous measurements with results from filter analysis introduced additional bias to the measurements. We also recommend to calibrate the ambient aerosol monitoring instruments using aerosol standards rather than gas-phase standards. The fitting approach for ACSM relative ionization for sulfate was shown to improve the comparisons between ACSM and collocated measurements in the absence of calibrated values, suggesting the importance of adding sulfate calibration into the ACSM calibration routine

Expression of SMARCD1 interacts with age in association with asthma control on inhaled corticosteroid therapy.

BackgroundGlobal gene expression levels are known to be highly dependent upon gross demographic features including age, yet identification of age-related genomic indicators has yet to be comprehensively undertaken in a disease and treatment-specific context.MethodsWe used gene expression data from CD4+ lymphocytes in the Asthma BioRepository for Integrative Genomic Exploration (Asthma BRIDGE), an open-access collection of subjects participating in genetic studies of asthma with available gene expression data. Replication population participants were Puerto Rico islanders recruited as part of the ongoing Genes environments &amp; Admixture in Latino Americans (GALA II), who provided nasal brushings for transcript sequencing. The main outcome measure was chronic asthma control as derived by questionnaires. Genomic associations were performed using regression of chronic asthma control score on gene expression with age in years as a covariate, including a multiplicative interaction term for gene expression times age.ResultsThe SMARCD1 gene (SWI/SNF-related matrix-associated actin-dependent regulator of chromatin subfamily D member 1) interacted with age to influence chronic asthma control on inhaled corticosteroids, with a doubling of expression leading to an increase of 1.3 units of chronic asthma control per year (95% CI [0.86, 1.74], p = 6 × 10- 9), suggesting worsening asthma control with increasing age. This result replicated in GALA II (p = 3.8 × 10- 8). Cellular assays confirmed the role of SMARCD1 in glucocorticoid response in airway epithelial cells.ConclusionFocusing on age-dependent factors may help identify novel indicators of asthma medication response. Age appears to modulate the effect of SMARCD1 on asthma control with inhaled corticosteroids

The politics of playing along: radio and regulation in democratic Europe

The loss of localism has been a common trend in most radio markets in Europe and the United States. Deregulation of ownership led to a concentration phenomenon that has affected local radios in several western democracies. New forms of regulation have been considered as possible ways to stop the erosion of localism by applying rules to markets in the defense of diversity, pluralism, and the local dimension. This article analyses the local radio market in Portugal, by assessing the changes in the legislation and by examining the regulatory action that can, according to its remit, act preventively to avoid market forces to harm these principles.info:eu-repo/semantics/publishedVersio

Genome-Wide Association Study of Anthropometric Traits and Evidence of Interactions With Age and Study Year in Filipino Women

Increased values of multiple adiposity-related anthropometric traits are important risk factors for many common complex diseases. We performed a genome-wide association (GWA) study for four quantitative traits related to body size and adiposity (body mass index [BMI], weight, waist circumference, and height) in a cohort of 1,792 adult Filipino women from the Cebu Longitudinal Health and Nutrition Survey. This is the first GWA study of anthropometric traits in Filipinos, a population experiencing a rapid transition into a more obesogenic environment. In addition to identifying suggestive evidence of additional SNP association signals (P < 10−5), we replicated (P < 0.05, same direction of additive effect) associations previously reported in European populations of both BMI and weight with MC4R and FTO, of BMI with BDNF, and of height with EFEMP1, ZBTB38, and NPPC, but none with waist circumference. We also replicated loci reported in Japanese or Korean populations as associated with BMI (OTOL1) and height (HIST1H1PS2, C14orf145, GPC5). A difference in local linkage disequilibrium between European and Asian populations suggests a narrowed association region for BDNF, while still including a proposed functional non-synonymous amino acid substitution variant (rs6265, Val66Met). Finally, we observed significant evidence (P < 0.0042) for age-by-genotype interactions influencing BMI for rs17782313 (MC4R) and rs9939609 (FTO), and for a study year-by-genotype interaction for rs4923461 (BDNF). Our results show that several genetic risk factors are associated with anthropometric traits in Filipinos and provide further insight into the effects of BDNF, FTO, and MC4R on BMI

Clinicopathological and prognostic significance of RECQL5 helicase expression in breast cancers

RECQL5 is a member of the RecQ family of DNA helicases and has key roles in homologous recombination, base excision repair, replication and transcription. The clinicopathological significance of RECQL5 expression in breast cancer is unknown. In the current study we have evaluated RECQL5 mRNA expression in 1977 breast cancers, and RECQL5 protein level in 1902 breast cancers [Nottingham Tenovus series (n=1650) and ER- cohort (n=252)]. Expression levels were correlated to aggressive phenotypes and survival outcomes. High RECQL5 mRNA expression was significantly associated with high histological grade (p=0.007), HER2 overexpression (p=0.032), ER+/HER2-/high proliferation genefu subtype, integrative molecular clusters (intClust 1and 9) and poor breast cancer specific survival (BCSS) (ps<0.0001). In sub-group analysis, high RECQL5 mRNA level remains significantly associated with poor BCSS in ER+ cohort (p<0.0001) but not in ER- cohort (p=0.116). At the protein level, in tumours with low RAD51, high RECQL5 level was significantly associated with high histological grade (p<0.0001), higher mitotic index (p=0.008), de-differentiation (p=0.025), pleomorphism (p=0.027) and poor BCSS (P=0.003). In sub-group analysis, high RECQL5/low RAD51 remains significantly associated with poor BCSS in ER+ cohort (p=0.010), but not in ER- cohort (p=0.628). In multivariate analysis, high RECQL5 mRNA and high RECQL5/low RAD51 nuclear protein co-expression independently influenced BCSS (p=0.022) in whole cohort and in the ER+ sub-group. Pre-clinically, we show that exogenous expression of RECQL5 in MCF10A cells can drive proliferation supporting an oncogenic function for RECQL5 in breast cancer. We conclude that RECQL5 is a promising biomarker in breast cancer

Biological, clinical and population relevance of 95 loci for blood lipids.

Plasma concentrations of total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol and triglycerides are among the most important risk factors for coronary artery disease (CAD) and are targets for therapeutic intervention. We screened the genome for common variants associated with plasma lipids in &gt;100,000 individuals of European ancestry. Here we report 95 significantly associated loci (P &lt; 5 x 10(-8)), with 59 showing genome-wide significant association with lipid traits for the first time. The newly reported associations include single nucleotide polymorphisms (SNPs) near known lipid regulators (for example, CYP7A1, NPC1L1 and SCARB1) as well as in scores of loci not previously implicated in lipoprotein metabolism. The 95 loci contribute not only to normal variation in lipid traits but also to extreme lipid phenotypes and have an impact on lipid traits in three non-European populations (East Asians, South Asians and African Americans). Our results identify several novel loci associated with plasma lipids that are also associated with CAD. Finally, we validated three of the novel genes-GALNT2, PPP1R3B and TTC39B-with experiments in mouse models. Taken together, our findings provide the foundation to develop a broader biological understanding of lipoprotein metabolism and to identify new therapeutic opportunities for the prevention of CAD

Cytotoxicity of ZnO Nanoparticles Can Be Tailored by Modifying Their Surface Structure: A Green Chemistry Approach for Safer Nanomaterials

ZnO nanoparticles (NP) are extensively used in numerous nanotechnology applications; however, they also happen to be one of the most toxic nanomaterials. This raises significant environmental and health concerns and calls for the need to develop new synthetic approaches to produce safer ZnO NP, while preserving their attractive optical, electronic, and structural properties. In this work, we demonstrate that the cytotoxicity of ZnO NP can be tailored by modifying their surface-bound chemical groups, while maintaining the core ZnO structure and related properties. Two equally sized (9.26 ± 0.11 nm) ZnO NP samples were synthesized from the same zinc acetate precursor using a forced hydrolysis process, and their surface chemical structures were modified by using different reaction solvents. X-ray diffraction and optical studies showed that the lattice parameters, optical properties, and band gap (3.44 eV) of the two ZnO NP samples were similar. However, FTIR spectroscopy showed significant differences in the surface structures and surface-bound chemical groups. This led to major differences in the zeta potential, hydrodynamic size, photocatalytic rate constant, and more importantly, their cytotoxic effects on Hut-78 cancer cells. The ZnO NP sample with the higher zeta potential and catalytic activity displayed a 1.5-fold stronger cytotoxic effect on cancer cells. These results suggest that by modifying the synthesis parameters/conditions and the surface chemical structures of the nanocrystals, their surface charge density, catalytic activity, and cytotoxicity can be tailored. This provides a green chemistry approach to produce safer ZnO NP