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In the family of protein arginine methyltransferases (PRMTs) that predominantly generate either asymmetric or symmetric dimethylarginine (SDMA), PRMT7 is unique in producing solely monomethylarginine (MMA) products. The type of methylation on histones and other proteins dictates changes in gene expression, and numerous studies have linked altered profiles of methyl marks with disease phenotypes. Given the importance of specific inhibitor development, it is crucial to understand the mechanisms by which PRMT product specificity is conferred. We have focused our attention on active-site residues of PRMT7 from the protozoan Trypanosoma brucei. We have designed 26 single and double mutations in the active site, including residues in the Glu-Xaa(8)-Glu (double E) loop and the Met-Gln-Trp sequence of the canonical Thr-His-Trp (THW) loop known to interact with the methyl-accepting substrate arginine. Analysis of the reaction products by high resolution cation exchange chromatography combined with the knowledge of PRMT crystal structures suggests a model where the size of two distinct subregions in the active site determines PRMT7 product specificity. A dual mutation of Glu-181 to Asp in the double E loop and Gln-329 to Ala in the canonical THW loop enables the enzyme to produce SDMA. Consistent with our model, the mutation of Cys-431 to His in the THW loop of human PRMT9 shifts its product specificity from SDMA toward MMA. Together with previous results, these findings provide a structural basis and a general model for product specificity in PRMTs, which will be useful for the rational design of specific PRMT inhibitors.

The impact of alpha linolenic acid (ALA), EPA, and DHA on obesity and metabolic complications was studied in mice fed a high-fat, high-sucrose (HF) diet. HF diets were supplemented with ALA, EPA, or DHA (1% w/w) and given to C57BL/6J mice for 16 weeks and to Ob/Ob mice for 6 weeks. In C57BL/6J mice, EPA reduced plasma cholesterol (-20%), limited fat mass accumulation (-23%) and adipose cell hypertrophy (-50%), and reduced plasma leptin concentration (-60%) compared with HF-fed mice. Furthermore, mice supplemented with EPA exhibited a higher insulin sensitivity (+24%) and glucose tolerance (+20%) compared with HF-fed mice. Similar effects were observed in EPA-supplemented Ob/Ob mice, although fat mass accumulation was not prevented. By contrast, in comparison with HF-fed mice, DHA did not prevent fat mass accumulation, increased plasma leptin concentration (+128%) in C57BL/6J mice, and did not improve glucose homeostasis in C57BL/6J and Ob/Ob mice. In 3T3-L1 adipocytes, DHA stimulated leptin expression whereas EPA induced adiponectin expression, suggesting that improved leptin/adiponectin balance may contribute to the protective effect of EPA.(jlr) In conclusion, supplementation with EPA, but not ALA and DHA, could preserve glucose homeostasis in an obesogenic environment and limit fat mass accumulation in the early stage of weight gain.-Pinel, A., E. Pitois, J-P. Rigaudiere, C. Jouve, S. De Saint-Vincent, B. Laillet, C. Montaurier, A. Huertas, B. Morio, and F. Capel. EPA prevents fat mass expansion and metabolic disturbances in mice fed with a Western diet.

Emerging evidence has shown that noncoding RNAs, particularly microRNAs (miRNAs), contribute to the pathogenesis of mood and anxiety disorders, although the molecular mechanisms are poorly understood. Here, we show that altered levels of miR17-92 in adult hippocampal neural progenitors have a significant impact on neurogenesis and anxiety and depression-related behaviors in mice. miR-1792 deletion in adult neural progenitors decreases neurogenesis in the dentate gyrus, while its overexpression increases neurogenesis. miR-17-92 affects neurogenesis by regulating genes in the glucocorticoid pathway, especially serum- and glucocorticoid- inducible protein kinase-1 (Sgk1). miR-17-92 knockout mice show anxiety-and depression-like behaviors, whereas miR-17-92 overexpressing mice exhibit anxiolytic and antidepression-like behaviors. Furthermore, we show that miR-17-92 expression in the adult mouse hippocampus responds to chronic stress, and miR-17-92 rescues proliferation defects induced by corticosterone in hippocampal neural progenitors. Our study uncovers a crucial role for miR-17-92 in adult neural progenitors through regulation of neurogenesis and anxiety-and depression-like behaviors.

Polyamines play important roles in a range of cellular processes. In this issue of Cell Host & Microbe, Mounce et al. (2016) link polyamine metabolism to the interferon response and demonstrate proviral effects for polyamines. The study points to the pathway as a potential novel pan-viral therapeutic target.

A search for exclusive or quasi-exclusive gamma gamma -> W (+) W (-) production, via pp -> p ((*)) W (+) W (-) p ((*)) -> p ((*)) mu (+/-)e(a") p ((*)) at TeV, is reported using data corresponding to an integrated luminosity of 19.7 fb(-1). Events are selected by requiring the presence of an electron-muon pair with large transverse momentum p (T)(mu (+/-)e(a")) > 30 GeV, and no associated charged particles detected from the same vertex. The 8 TeV results are combined with the previous 7 TeV results (obtained for 5.05 fb(-1) of data). In the signal region, 13 (2) events are observed over an expected background of 3.9 +/- 0.6 (0.84 +/- 0.15) events for 8 (7) TeV, resulting in a combined excess of 3.4 sigma over the background-only hypothesis. The observed yields and kinematic distributions are compatible with the standard model prediction for exclusive and quasi-exclusive gamma gamma -> W (+) W (-) production. Upper limits on the anomalous quartic gauge coupling operators a (0,C) (W) (dimension-6) and f (M0,1,2,3) (dimension-8), the most stringent to date, are derived from the measured dilepton transverse momentum spectrum.

The exclusive deep inelastic electroproduction of psi(2S) and J/psi (1S) at an ep centre-of-mass energy of 317 GeV has been studied with the ZEUS detector at HERA in the kinematic range 2 < Q(2) < 80 GeV2, 30 < W < 210 GeV and vertical bar t vertical bar < 1 GeV2, where Q(2) is the photon virtuality, W is the photon-proton centre-of-mass energy and t is the squared four-momentum transfer at the proton vertex. The data for 2 < Q(2) < 5 GeV2 were taken in the HERA I running period and correspond to an integrated luminosity of 114 pb(-1). The data for 5 < Q(2) < 80 GeV2 are from both HERA I and HERA II periods and correspond to an integrated luminosity of 468 pb(-1). The decay modes analysed were mu(+)mu(-) and J/psi(1S)pi(+)pi(-) for the psi(2S) and mu(+)mu(-) for the J/psi(1S). The cross-section ratio sigma(psi(2S))/sigma(J/psi(1S)) has been measured as a function of Q(2), W and t. The results are compared to predictions of QCD-inspired models of exclusive vector-meson production. (C) 2016 The Author(s). Published by Elsevier B.V.

Over the past 20 years, breakthrough discoveries of chromatin-modifying enzymes and associated mechanisms that alter chromatin in response to physiological or pathological signals have transformed our knowledge of epigenetics from a collection of curious biological phenomena to a functionally dissected research field. Here, we provide a personal perspective on the development of epigenetics, from its historical origins to what we define as 'the modern era of epigenetic research'. We primarily highlight key molecular mechanisms of and conceptual advances in epigenetic control that have changed our understanding of normal and perturbed development.

Background: Understanding the relationship between a stimulus and how it is perceived reveals fundamental principles about the mechanisms of sensory perception. While this stimulus-percept problem is mostly understood for color vision and tone perception, it is not currently possible to predict how a given molecule smells. While there has been some progress in predicting the pleasantness and intensity of an odorant, perceptual data for a larger number of diverse molecules are needed to improve current predictions. Towards this goal, we tested the olfactory perception of 480 structurally and perceptually diverse molecules at two concentrations using a panel of 55 healthy human subjects. Results: For each stimulus, we collected data on perceived intensity, pleasantness, and familiarity. In addition, subjects were asked to apply 20 semantic odor quality descriptors to these stimuli, and were offered the option to describe the smell in their own words. Using this dataset, we replicated several previous correlations between molecular features of the stimulus and olfactory perception. The number of sulfur atoms in a molecule was correlated with the odor quality descriptors "garlic," "fish," and "decayed," and large and structurally complex molecules were perceived to be more pleasant. We discovered a number of correlations in intensity perception between molecules. We show that familiarity had a strong effect on the ability of subjects to describe a smell. Many subjects used commercial products to describe familiar odorants, highlighting the role of prior experience in verbal reports of olfactory perception. Nonspecific descriptors like "chemical" were applied frequently to unfamiliar odorants, and unfamiliar odorants were generally rated as neither pleasant nor unpleasant. Conclusions: We present a very large psychophysical dataset and use this to correlate molecular features of a stimulus to olfactory percept. Our work reveals robust correlations between molecular features and perceptual qualities, and highlights the dominant role of familiarity and experience in assigning verbal descriptors to odorants.

We show here that the Saccharomyces cerevisiae GARP complex and the Cog1-4 subcomplex of the COG complex, both members of the complexes associated with tethering containing helical rods (CATCHR) family of multisubunit tethering complexes, share the same subunit organization. We also show that HOPS, a tethering complex acting in the endolysosomal pathway, shares a similar architecture, thus suggesting that multisubunit tethering complexes use related structural frameworks.

Individuals with developmental prosopagnosia (DP) exhibit severe difficulties in recognizing faces and to a lesser extent, also exhibit difficulties in recognizing non-face objects. We used fMRI to investigate whether these behavioral deficits could be accounted for by altered spontaneous neural activity. Two aspects of spontaneous neural activity were measured: the intensity of neural activity in a voxel indexed by the fractional amplitude of spontaneous low-frequency fluctuations (fALFF), and the connectivity of a voxel to neighboring voxels indexed by regional homogeneity (ReHo). Compared with normal adults, both the fALFF and ReHo values within the right occipital face area (rOFA) were significantly reduced in DP subjects. Follow-up studies on the normal adults revealed that these two measures indicated further functional division of labor within the rOFA. The fALFF in the rOFA was positively correlated with behavioral performance in recognition of non-face objects, whereas ReHo in the rOFA was positively correlated with processing of faces. When considered together, the altered fALFF and ReHo within the same region (rOFA) may account for the comorbid deficits in both face and object recognition in DPs, whereas the functional division of labor in these two measures helps to explain the relative independency of deficits in face recognition and object recognition in DP. (C) 2016 Elsevier Ltd. All rights reserved.