NMR-based metabolic characterization of chicken tissues and biofluids: a model for avian research

Introduction Poultry is one of the most consumed meat in the world and its related industry is always looking for ways to improve animal welfare and productivity. It is therefore essential to understand the metabolic response of the chicken to new feed formulas, various supplements, infections and treatments. Objectives As a basis for future research investigating the impact of diet and infections on chicken’s metabolism, we established a high-resolution proton nuclear magnetic resonance (NMR)-based metabolic atlas of the healthy chicken (Gallus gallus). Methods Metabolic extractions were performed prior to 1H-NMR and 2D NMR spectra acquisition on twelve biological matrices: liver, kidney, spleen, plasma, egg yolk and white, colon, caecum, faecal water, ileum, pectoral muscle and brain of 6 chickens. Metabolic profiles were then exhaustively characterized. Results Nearly 80 metabolites were identified. A cross-comparison of these matrices was performed to determine metabolic variations between and within each section and highlighted that only eight core metabolites were systematically found in every matrice. Conclusion This work constitutes a database for future NMR-based metabolomic investigations in relation to avian production and health

Genome-wide association mapping identifies a new arsenate reductase enzyme critical for limiting arsenic accumulation in plants

Inorganic arsenic is a carcinogen, and its ingestion through foods such as rice presents a significant risk to human health. Plants chemically reduce arsenate to arsenite. Using genome-wide association (GWA) mapping of loci controlling natural variation in arsenic accumulation in Arabidopsis thaliana allowed us to identify the arsenate reductase required for this reduction, which we named High Arsenic Content 1 (HAC1). Complementation verified the identity of HAC1, and expression in Escherichia coli lacking a functional arsenate reductase confirmed the arsenate reductase activity of HAC1. The HAC1 protein accumulates in the epidermis, the outer cell layer of the root, and also in the pericycle cells surrounding the central vascular tissue. Plants lacking HAC1 lose their ability to efflux arsenite from roots, leading to both increased transport of arsenic into the central vascular tissue and on into the shoot. HAC1 therefore functions to reduce arsenate to arsenite in the outer cell layer of the root, facilitating efflux of arsenic as arsenite back into the soil to limit both its accumulation in the root and transport to the shoot. Arsenate reduction by HAC1 in the pericycle may play a role in limiting arsenic loading into the xylem. Loss of HAC1-encoded arsenic reduction leads to a significant increase in arsenic accumulation in shoots, causing an increased sensitivity to arsenate toxicity. We also confirmed the previous observation that the ACR2 arsenate reductase in A. thaliana plays no detectable role in arsenic metabolism. Furthermore, ACR2 does not interact epistatically with HAC1, since arsenic metabolism in the acr2 hac1 double mutant is disrupted in an identical manner to that described for the hac1 single mutant. Our identification of HAC1 and its associated natural variation provides an important new resource for the development of low arsenic-containing food such as rice

D.: Effect of inhibition of -yglutamyl transpeptidase on biliary and urinary excretion of glutathione-derived thiols and methylmercury

ABSTRACT ABBREVIATIONS: CYSSG, disulfide of Cys and reduced glutathione; GS, glutathione; GSH, reduced glutathione; GSSG, odixized glutathione; GGT, -y-glutamyftranspeptidase

Fuzziness enables context dependence of protein interactions

Proteins may undergo adaptive structural transitions to accommodate to their cellular milieu and respond to external signals. Modulation of conformational ensembles can rewire the intra- or intermolecular interaction networks and shift between different functional states. Adaptive conformational transitions are associated with protein fuzziness, which enables (a) rewiring interaction networks via alternative motifs, (b) new functional features via allosteric motifs, (c) functional switches upon post-translational modifications, or (d) regulation of higher-order organizations. We propose that all these context-dependent functional changes are intertwined with structural multiplicity or dynamic disorder in protein assemblies and can only be described by stochastic structure\u2013function relationships

Women\u27s Experiences of Sexual Attention: A Cross-Sectional Study of U.S. University Students

This cross-sectional investigation of women\u27s experiences of sexual attention examined the role of dispositional and situational variables in how women experienced sexual attention (as positive, negative, or neutral). Methods: Participants were 350U.S. college women recruited from undergraduate psychology courses. They completed questionnaires on objectified body consciousness, social physique anxiety, self-esteem, body esteem, and social desirability. A subset (N = 275) also reported retrospectively on experiences with sexual attention in 1 of 4 contexts: at a bar/club, at a gym, at school, or at work. It was hypothesized that the context where sexual attention occurs would be associated with how positive or negative the encounter was experienced. Results: The relationship between context and experience of sexual attention approached but did not achieve significance. When controlling for demographic variables and social desirability, self-esteem and body esteem were negatively associated with self-objectification and social physique anxiety. White women younger than the age of 25 with higher body mass index were most likely to engage in self-objectifying behaviors. Themes identified from responses to open-ended questions describe reasons for experiencing sexual attention to be uncomfortable or pleasurable. Conclusions: There is wide variability in women\u27s experiences of sexual attention. Self-esteem and body esteem may protect against self-objectification. Future studies should examine how contextual factors influence women\u27s experiences of sexual attention