| Re-engineering the zinc fingers of PRDM9 reverses hybrid sterility in mice PRDM9 is a DNA-binding protein that controls the position of double-strand breaks in meiosis, and the gene that encodes it is responsible for hybrid infertility between closely related mouse species; this hybrid infertility is eliminated by introducing the zinc-finger domain sequence from the human version of the PRDM9 gene, a change which alters both the position of double-strand breaks and the symmetry of PRDM9 binding and suggests that PRDM9 may have a more general but transient role in the early stages of speciation. | Naturally occurring p16Ink4a-positive cells shorten healthy lifespan When senescent cells accumulate during adulthood they negatively influence lifespan and promote age-dependent changes in several organs; clearance of these cells delayed tumorigenesis in mice and attenuated age-related deterioration of several organs without overt side effects, suggesting that the therapeutic removal of senescent cells may be able to extend healthy lifespan. | Cryo-EM structure of the yeast U4/U6.U5 tri-snRNP at 3.7 Å resolution A 3.7 Å resolution structure for the yeast U4/U6.U5 tri-snRNP, a complex involved in splicing, allows a better appreciation of the architecture of the tri-snRNP, and offers new functional insights into the activation of the spliceosome and the assembly of the catalytic core. | Observing the Rosensweig instability of a quantum ferrofluid Spontaneous translational symmetry breaking is experimentally observed in a dipolar Bose–Einstein condensate of dysprosium atoms, whereby an instability causes a spontaneous transition from an unstructured superfluid to an ordered arrangement of droplet crystals, which is surprisingly long-lived. | Covariation of deep Southern Ocean oxygenation and atmospheric CO2 through the last ice age A reconstruction of changes in ocean oxygenation throughout the last glacial cycle shows that respired carbon was removed from the deep Southern Ocean during deglaciation and Antarctic warm events, consistent with a prominent role of reduced iron fertilization and enhanced ocean ventilation, modifying atmospheric carbon dioxide concentrations over the past 80,000 years. | Multistage coupling of independent laser-plasma accelerators Laser-plasma particle accelerators offer much higher acceleration than conventional methods, which could enable high-energy applications; here two separate accelerator stages, driven by two independent lasers, are coupled using plasma-based optics. | Backbone NMR reveals allosteric signal transduction networks in the β1-adrenergic receptor Although several X-ray crystal structures of G protein-coupled receptors (GPCRs) have been reported, relatively little is known about the conformational dynamics of these important membrane proteins; here, the authors used NMR spectroscopy to monitor the conformational changes that occur in the turkey β1-adrenergic receptor in the presence of antagonists, partial agonists, and full agonists. | Late acquisition of mitochondria by a host with chimaeric prokaryotic ancestry Evidence that among the eukaryotic ancestor genes, those derived from the proto-mitochondrion have the closest evolutionary distances to their bacterial relatives. | Real-time, portable genome sequencing for Ebola surveillance A nanopore DNA sequencer is used for real-time genomic surveillance of the Ebola virus epidemic in the field in Guinea; the authors demonstrate that it is possible to pack a genomic surveillance laboratory in a suitcase and transport it to the field for on-site virus sequencing, generating results within 24 hours of sample collection. | | Structural disorder of monomeric α-synuclein persists in mammalian cells Atomic resolution in-cell NMR and EPR spectroscopy show that the human amyloid protein α-synuclein remains disordered within all mammalian cells tested, including neurons, and identifies which parts of the protein dynamically interact or remain shielded from the cytoplasm, thus counteracting aggregation under physiological cell conditions. Francois-Xavier Theillet, Andres Binolfi, Beata Bekei et al. | Persistent HIV-1 replication maintains the tissue reservoir during therapy By examining viral sequences in lymphoid tissue from three HIV-1-infected individuals receiving drug therapy, the authors find phylogenetic evidence for ongoing virus replication, suggesting that the antiretroviral drug concentration in the lymphoid tissue is insufficient to fully suppress the virus; using a mathematical model, they further explain why drug resistance does not necessarily arise as a result. Ramon Lorenzo-Redondo, Helen R. Fryer, Trevor Bedford et al. | Active medulloblastoma enhancers reveal subgroup-specific cellular origins Genomic studies of the paediatric brain tumour medulloblastoma have revealed four clinically distinct molecular subgroups; here active gene regulatory elements in 28 primary medulloblastoma tissues are mapped to reveal differentially regulated enhancers across the different subgroups, allowing insights into the transcription factors that characterize subgroup divergence and the cellular origin of the poorly characterized Group 3 and 4 subgroups. Charles Y. Lin, Serap Erkek, Yiai Tong et al. | | A homogeneous nucleus for comet 67P/Churyumov–Gerasimenko from its gravity field The precise mass, bulk density, porosity and internal structure of the nucleus of comet 67P/Churyumov–Gerasimenko are calculated, on the basis of its gravity field, showing it to be dusty, homogeneous, low-density and highly porous. M. Pätzold, T. Andert, M. Hahn et al. | Optical attosecond pulses and tracking the nonlinear response of bound electrons Intense light pulses in the visible and adjacent spectral ranges with their energy mostly confined to a half wave cycle—optical attosecond pulses—are synthesized and used to measure the time it takes electrons to respond to light. M. Th. Hassan, T. T. Luu, A. Moulet et al. | Bioresorbable silicon electronic sensors for the brain Electronic implants are often used in diagnosing and treating human illness, but permanent implants come with problems; here, devices are described that can sense temperature, pressure, pH or thermal characteristics, and—crucially—are fully resorbable by the body. Seung-Kyun Kang, Rory K. J. Murphy, Suk-Won Hwang et al. | Sub-particle reaction and photocurrent mapping to optimize catalyst-modified photoanodes Using single-molecule fluorescence imaging of photoelectrocatalysis, the charge-carrier activities on single TiO2 nanorods and the corresponding water-oxidation photocurrent are mapped at high spatiotemporal resolution, revealing the best catalytic sites and the most effective sites for depositing an oxygen evolution catalyst. Justin B. Sambur, Tai-Yen Chen, Eric Choudhary et al. | Dehydration of lawsonite could directly trigger earthquakes in subducting oceanic crust Deformation experiments on lawsonite reveal that unstable fault slip occurs during dehydration reactions with continuous acoustic emission signals; this indicates the potential for unstable frictional sliding in natural lawsonite layers, which could possibly be the source of intermediate-depth earthquakes in cold subduction zones. Keishi Okazaki, Greg Hirth | Historical nectar assessment reveals the fall and rise of floral resources in Britain Historical assessment of nectar provision in the UK from the 1930s to 2007 shows an initial dramatic fall, but more recently nectar provision has increased; the diversity of nectar sources has fallen to the point that four species now produce half of the total UK nectar. Mathilde Baude, William E. Kunin, Nigel D. Boatman et al. | Xenacoelomorpha is the sister group to Nephrozoa Robust phylogenetic analysis based on transcriptomes of Xenoturbella and acoelomorph worms shows that Xenacoelomorpha is an early bilaterian lineage forming the sister group to Nephrozoa. Johanna Taylor Cannon, Bruno Cossermelli Vellutini, Julian Smith et al. | New deep-sea species of Xenoturbella and the position of Xenacoelomorpha Description of four new species of Xenoturbella and phylogenomic analyses, aligning Xenacoelomorpha as sister group to the rest of Bilateria, or as sister to Protostomia. Greg W. Rouse, Nerida G. Wilson, Jose I. Carvajal et al. | Autism-like behaviours and germline transmission in transgenic monkeys overexpressing MeCP2 Lentivirus-based transgenic Macaca fascicularis monkeys are generated expressing the human MECP2 transgene in the brain, and they display behavioural alterations including changes in social interaction and increased anxiety; germline transmission of the transgene to the F1 offspring is shown, and these monkeys also had an altered social interaction phenotype. Zhen Liu, Xiao Li, Jun-Tao Zhang et al. | The temporal scaling of Caenorhabditis elegans ageing A diverse range of molecular and genetic manipulations all alter lifespan distributions of Caenorhabditis elegans by an apparent stretching or shrinking of time. Nicholas Stroustrup, Winston E. Anthony, Zachary M. Nash et al. | An essential receptor for adeno-associated virus infection An adeno-associated virus (AAV) receptor protein essential for AAV2 entry into cells is identified; AAV receptor binds directly to the virus, and its ablation renders a diverse range of mammalian cell types and mice resistant to infection by AAV of multiple serotypes. S. Pillay, N. L. Meyer, A. S. Puschnik et al. | Genome-wide nucleosome specificity and function of chromatin remodellers in ES cells Genome-wide binding profiles for eight different chromatin remodellers in mouse embryonic stem (ES) cells are determined at single nucleosome resolution; each remodeller binds at specific nucleosome positions relative to the start of genes, and the same remodeller acts as a positive or negative regulator of transcription depending on the promoter chromatin organization and epigenetic marking of the gene it binds. Maud de Dieuleveult, Kuangyu Yen, Isabelle Hmitou et al. | | | | |
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