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McEwen BS, McEwen CA
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Response to Jerome Kagan's Essay on Stress (2016)

PERSPECTIVES ON PSYCHOLOGICAL SCIENCE 2016 JUL; 11(4):451-455
To be useful, the concept of stress needs to be defined in biological terms linked to a broader framework of allostasis and its role in the adaptation of brain and body to positive and negative life experiences. A clear biological framework helps connect and organize animal and human research on stress. In particular, the concepts of toxic stress and allostatic load and overload highlight those experiences and situations that, as Kagan says, compromise an organism's health and capacity to cope with daily challenges (p. 442). A deeper understanding is needed of the epigenetic influences throughout the life course that contribute both to these negative outcomes and to positive ones.
Tejera F, Reyes A, Altshuler E
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Uninformed sacrifice: Evidence against long-range alarm transmission in foraging ants exposed to localized abduction

EUROPEAN PHYSICAL JOURNAL-SPECIAL TOPICS 2016 JUL; 225(4):663-668
It is well established that danger information can be transmitted by ants through relatively small distances, provoking either a state of alarm when they move away from potentially dangerous stimulus, or charge toward it aggressively. There is almost no knowledge if danger information can be transmitted along large distances. In this paper, we abduct leaf cutting ants of the species Atta insularis while they forage in their natural environment at a certain point of the foraging line, so ants make a "U" turn to escape from the danger zone and go back to the nest. Our results strongly suggest that those ants do not transmit "danger information" to other nestmates marching towards the abduction area. The individualistic behavior of the ants returning from the danger zone results in a depression of the foraging activity due to the systematic sacrifice of non-informed individuals.
Wang L, Zehir A, Nafa K, Zhou NY, Berger MF, Casanova J, Sadowska J, Lu C, Allis CD, Gounder M, Chandhanayingyong C, Ladanyi M, Boland PJ, Hameed M
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Genomic Aberrations Frequently Alter Chromatin Regulatory Genes in Chordoma

GENES CHROMOSOMES & CANCER 2016 JUL; 55(7):591-600
Chordoma is a rare primary bone neoplasm that is resistant to standard chemotherapies. Despite aggressive surgical management, local recurrence and metastasis is not uncommon. To identify the specific genetic aberrations that play key roles in chordoma pathogenesis, we utilized a genome-wide high-resolution SNP-array and next generation sequencing (NGS)-based molecular profiling platform to study 24 patient samples with typical histopathologic features of chordoma. Matching normal tissues were available for 16 samples. SNP-array analysis revealed nonrandom copy number losses across the genome, frequently involving 3, 9p, 1p, 14, 10, and 13. In contrast, copy number gain is uncommon in chordomas. Two minimum deleted regions were observed on 3p within a similar to 8 Mb segment at 3p21.1-p21.31, which overlaps SETD2, BAP1 and PBRM1. The minimum deleted region on 9p was mapped to CDKN2A locus at 9p21.3, and homozygous deletion of CDKN2A was detected in 5/22 chordomas (similar to 23%). NGS-based molecular profiling demonstrated an extremely low level of mutation rate in chordomas, with an average of 0.5 mutations per sample for the 16 cases with matched normal. When the mutated genes were grouped based on molecular functions, many of the mutation events (similar to 40%) were found in chromatin regulatory genes. The combined copy number and mutation profiling revealed that SETD2 is the single gene affected most frequently in chordomas, either by deletion or by mutations. Our study demonstrated that chordoma belongs to the C-class (copy number changes) tumors whose oncogenic signature is non-random multiple copy number losses across the genome and genomic aberrations frequently alter chromatin regulatory genes. (C) 2016 Wiley Periodicals, Inc.
Le Gall A, Cattoni DI, Guilhas B, Mathieu-Demaziere C, Oudjedi L, Fiche JB, Rech J, Abrahamsson S, Murray H, Bouet JY, Nollmann M
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Bacterial partition complexes segregate within the volume of the nucleoid

NATURE COMMUNICATIONS 2016 JUL; 7(?):? Article 12107
Precise and rapid DNA segregation is required for proper inheritance of genetic material. In most bacteria and archaea, this process is assured by a broadly conserved mitotic-like apparatus in which a NTPase (ParA) displaces the partition complex. Competing observations and models imply starkly different 3D localization patterns of the components of the partition machinery during segregation. Here we use super-resolution microscopies to localize in 3D each component of the segregation apparatus with respect to the bacterial chromosome. We show that Par proteins locate within the nucleoid volume and reveal that proper volumetric localization and segregation of partition complexes requires ATPase and DNA-binding activities of ParA. Finally, we find that the localization patterns of the different components of the partition system highly correlate with dense chromosomal regions. We propose a new mechanism in which the nucleoid provides a scaffold to guide the proper segregation of partition complexes.
Dar RD, Shaffer SM, Singh A, Razooky BS, Simpson ML, Raj A, Weinberger LS
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Transcriptional Bursting Explains the Noise-Versus-Mean Relationship in mRNA and Protein Levels

PLOS ONE 2016 JUL 28; 11(7):? Article e0158298
Recent analysis demonstrates that the HIV-1 Long Terminal Repeat (HIV LTR) promoter exhibits a range of possible transcriptional burst sizes and frequencies for any mean-expression level. However, these results have also been interpreted as demonstrating that cell-tocell expression variability (noise) and mean are uncorrelated, a significant deviation from previous results. Here, we re-examine the available mRNA and protein abundance data for the HIV LTR and find that noise in mRNA and protein expression scales inversely with the mean along analytically predicted transcriptional burst-sizemanifolds. We then experimentally perturb transcriptional activity to test a prediction of the multiple burst-size model: that increasing burst frequency will cause mRNA noise to decrease along given burst-size lines as mRNA levels increase. The data show that mRNA and protein noise decrease as mean expression increases, supporting the canonical inverse correlation between noise and mean.
Valente C, Hinds J, Gould KA, Pinto FR, de Lencastre H, Sa-Leao R
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Impact of the 13-valent pneumococcal conjugate vaccine on Streptococcus pneumoniae multiple serotype carriage

VACCINE 2016 JUL 25; 34(34):4072-4078
Introduction: Pneumococcal multiple serotype carriage is important for evolution of the species and to understand how the pneumococcal population is changing with vaccination. We aimed to determine the impact of the 13-valent pneumococcal conjugate vaccine (PCV13) on multiple serotype carriage. Methods and materials: Nasopharyngeal samples from fully vaccinated pneumococcal carriers (4 doses of PCV13, n = 141, aged 18-72 months) or from non-vaccinated pneumococcal carriers (0 doses of any PCV, n = 140, same age group) were analyzed. Multiple serotype carriage was evaluated by DNA hybridization with a molecular serotyping microarray that detects all known serotypes. Results: Vaccinated children had a lower prevalence of multiple serotype carriage than the non vaccinated group (20.6% vs 29.3%, p = 0.097), and a significantly lower proportion of PCV13 serotypes (6.4% vs 38.5%, p = 0.0001). PCV13 serotypes found among vaccinated children were mostly detected as a minor serotype in co-colonization with a more abundant non-vaccine serotype. Vaccinated children were colonized by a significantly higher proportion of commensal non-pneumococcal Streptococcus spp. (58.2% vs 42.8%, p = 0.012). In vaccinated children there were significantly less non-vaccine type (NVT) co-colonization events than expected based on the distribution of these serotypes in non vaccinated children. Conclusions: The results suggest that vaccinated children have lower pneumococcal multiple serotype carriage prevalence due to higher competitive abilities of non-vaccine serotypes expanding after PCV13 use. This might represent an additional benefit of PCV13, as decreased co-colonization rates translate into decreased opportunities for horizontal gene transfer and might have implications for the evolution and virulence of pneumococci. (C) 2016 Elsevier Ltd. All rights reserved.
Ramanan V, Trehan K, Ong ML, Luna JM, Hoffmann HH, Espiritu C, Sheahan TP, Chandrasekar H, Schwartz RE, Christine KS, Rice CM, van Oudenaarden A, Bhatia SN
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Viral genome imaging of hepatitis C virus to probe heterogeneous viral infection and responses to antiviral therapies

VIROLOGY 2016 JUL; 494(?):236-247
Hepatitis C virus (HCV) is a positive single-stranded RNA virus of enormous global health importance, with direct-acting antiviral therapies replacing an immunostimulatory interferon-based regimen. The dynamics of HCV positive and negative-strand viral RNAs (vRNAs) under antiviral perturbations have not been studied at the single-cell level, leaving a gap in our understanding of antiviral kinetics and host virus interactions. Here, we demonstrate quantitative imaging of HCV genomes in multiple infection models, and multiplexing of positive and negative strand vRNAs and host antiviral RNAs. We capture the varying kinetics with which antiviral drugs with different mechanisms of action clear HCV infection, finding the NS5A inhibitor daclatasvir to induce a rapid decline in negative-strand viral RNAs. We also find that the induction of host antiviral genes upon interferon treatment is positively correlated with viral load in single cells. This study adds smFISH to the toolbox available for analyzing the treatment of RNA virus infections. (C) 2016 Elsevier Inc. All rights reserved.
Kow LM, Pataky S, Dupre C, Phan A, Martin-Alguacil N, Pfaff DW
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Analyses of rapid estrogen actions on rat ventromedial hypothalamic neurons

STEROIDS 2016 JUL; 111(?):100-112
Rapid estrogen actions are widely diverse across many cell types. We conducted a series of electrophysiological studies on single rat hypothalamic neurons and found that estradiol (E2) could rapidly and independently potentiate neuronal excitation/depolarizations induced by histamine (HA) and N-Methyl-D-Aspartate (NMDA). Now, the present whole-cell patch study was designed to determine whether E2 potentiates HA and NMDA depolarizations - mediated by distinctly different types of receptors - by the same or by different mechanisms. For this, the actions of HA, NMDA, as well as E2, were investigated first using various ion channel blockers and then by analyzing and comparing their channel activating characteristics. Results indicate that: first, both HA and NMDA depolarize neurons by Inhibiting K+ currents. Second, E2 potentiates both HA and NMDA depolarizations by enhancing the inhibition of K+ currents, an inhibition caused by the two transmitters. Third, E2 employs the very same mechanism, the enhancement of K+ current inhibition, thus to rapidly potentiate HA and NMDA depolarizations. These data are of behavioral importance, since the rapid E2 potentiation of depolarization synergizes with nuclear genomic actions of E2 to facilitate lordosis behavior, the primary female-typical reproductive behavior. (C) 2016 Elsevier Inc. All rights reserved.
Yang S, Zheng XD, Lu C, Li GM, Allis CD, Li HT
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Molecular basis for oncohistone 113 recognition by SETD2 methyltransferase

GENES & DEVELOPMENT 2016 JUL 15; 30(14):1611-1616
High-frequency point mutations of genes encoding his tones have been identified recently as novel drivers in a number of tumors. Specifically, the H3K36M/I mutations were shown to be oncogenic in chondroblastomas and undifferentiated sarcomas by inhibiting H3K36 methyltransferases, including SETD2. Here we report the crystal structures of the SETD2 catalytic domain bound to H3K36M or H3K36I peptides with SAH (5-adenosylhomocysteine). In the complex structure, the catalytic domain adopts an open conformation, with the K36M/I peptide snuggly positioned in a newly formed substrate channel. Our structural and biochemical data reveal the molecular basis underying oncohistone recognition by and inhibition of SETD2.
Czarnowicki T, Krueger JG, Guttman-Yassky E
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Systemic B-cell abnormalities in patients with atopic dermatitis? Reply

JOURNAL OF ALLERGY AND CLINICAL IMMUNOLOGY 2016 JUL; 138(1):318-320