| | Microbiology: A beacon for bacterial tubulin
The protein FtsZ forms a ring structure that constricts to allow bacterial cells to divide. A second protein, MapZ, has now been found to guide FtsZ to the correct mid-cell position in the bacterium Streptococcus pneumoniae.
| Structural biology: Photosynthetic complex in close-up
Photosystem II, a photosynthetic protein complex, is prone to X-ray damage during crystallography. A high-resolution structure of the undamaged complex now offers a detailed view of its catalytic centre.
| Malaria: How vector mosquitoes beat the heat
Intensive longitudinal sampling of malaria mosquitoes in the African semi-desert reveals that three morphologically indistinguishable species have distinctive strategies for surviving the dry season.
| Materials science: Breakthrough for protons
The atomically thin material called graphene is impermeable to atoms as small as helium. The finding that protons can pass through it might enable new kinds of membrane to be developed and aid research into fuel cells.
| RNA helicase DDX21 coordinates transcription and ribosomal RNA processing
DEAD-box RNA helicase DDX21 is involved in both the transcription and RNA processing of ribosomal genes in human cells, sensing the transcriptional status of both RNA polymerase I and RNA polymerase II and associating with non-coding RNAs involved in ribonucleoprotein formation, possibly allowing for coordinated regulation of protein synthesis.
| Dynamics of genomic clones in breast cancer patient xenografts at single-cell resolution
Deep-genome and single-cell sequencing analyses of patient-derived breast cancer xenografts reveal extensive, dynamic and reproducible changes in intra-tumoral mutational clonal composition on engraftment and serial propagation.
| TRIM37 is a new histone H2A ubiquitin ligase and breast cancer oncoprotein
The RING finger protein TRIM37 is encoded by a gene that is amplified in certain breast cancers, but its function is unknown; here, it is shown to mono-ubiquitinate histone H2A and repress gene expression, and to function as a breast cancer oncoprotein.
| Transferred interbacterial antagonism genes augment eukaryotic innate immune function
Documented cases of horizontal gene transfer from bacteria to eukaryotes are rare, but now, not only is a new class of transferred genes identified, the function of one representative is also demonstrated in its new setting, where it controls bacterial growth.
| MapZ marks the division sites and positions FtsZ rings in Streptococcus pneumoniae
A new mechanism is identified for correct placement of the division machinery in Streptococcus pneumoniae that relies on the novel factor MapZ to form ring structures at the cell equator; these structures move apart as the cell elongates, acting as permanent markers of division sites.
| Interception of host angiogenic signalling limits mycobacterial growth
Using a model of tuberculosis in zebrafish, granuloma formation is shown to coincide with hypoxia and angiogenesis; furthermore, the pharmacological inhibition of the pro-angiogenic VEGF pathway reduces infection burden, suggesting a possible treatment strategy in patients with the disease.
| Conductive two-dimensional titanium carbide 'clay' with high volumetric capacitance
Two-dimensional titanium carbide has been produced by etching out aluminium in a lithium fluoride and hydrochloric acid mixture; it is hydrophilic and mouldable like clay and has excellent volumetric capacitance and cyclability, properties that are desirable for portable electronics.
| Signatures of aestivation and migration in Sahelian malaria mosquito populations
Malaria-carrying mosquitoes nearly disappear in the dry season, yet they reappear suddenly following the first rains; using surveys of mosquito densities, the authors characterize the population dynamics of the three main vector species and use these to infer persistence by long-distance migration in two species and aestivation in the third.
| Native structure of photosystem II at 1.95 Å resolution viewed by femtosecond X-ray pulses
The radiation-damage-free structure of the photosystem II membrane protein complex, which oxidizes water into dioxygen in an oxygen evolving complex, has been determined by an X-ray free electron laser at a resolution of 1.95 Å; one of the substrate oxygen atoms in this reaction is now identified.
| Proton transport through one-atom-thick crystals
Measurements show that monolayers of graphene and hexagonal boron nitride are unexpectedly highly permeable to thermal protons and that their conductivity rapidly increases with temperature, but that no proton transport is detected for few-layer crystals.
| | Belowground biodiversity and ecosystem functioning
Growing evidence points to belowground biota as a significant contributor to aboveground diversity and functioning as well as impacting eco-evolutionary responses to environmental change; this review explores such evidence and proposes further research directions.
Richard D. Bardgett, Wim H. van der Putten | | Global diets link environmental sustainability and human health
As incomes grow, diets change, with varying impacts on human health and the environment; here the links are examined and suggestions made for diets that both improve health and minimize environmental impacts.
David Tilman, Michael Clark | A positional Toll receptor code directs convergent extension in Drosophila
Body axis elongation from head to tail is essential for animal development, however, the spatial cues that direct cell rearrangements relative to the anterior–posterior axis were unknown; this Drosophila study of convergent extension reveals that three Toll family receptors, expressed in overlapping stripes, modulate the contractile properties of cells to generate the polarized cell rearrangements that lead to body axis elongation.
Adam C. Paré, Athea Vichas, Christopher T. Fincher et al. | First cranial remains of a gondwanatherian mammal reveal remarkable mosaicism
The gondwanatherians were mammals known only from teeth and some jaw fragments that lived in the southern continents alongside dinosaurs; here the entire cranium of a bizarre and badger-sized fossil mammal from the Cretaceous of Madagascar shows that gondwanatherians were related to the better-known multituberculates, a long-lived and successful group of now-extinct rodent-like mammals.
David W. Krause, Simone Hoffmann, John R. Wible et al. | | A dust-parallax distance of 19 megaparsecs to the supermassive black hole in NGC 4151
A distance measurement based on observations of the hot-dust emitting region of the active galaxy NGC 4151 yields a value of 19 megaparsecs, implying a 1.4-fold increase in the dynamical mass of the galaxy's central black hole and a corresponding correction to emission line reverberation masses of black holes in other active galactic nuclei if calibrated against NGC 4151′s dynamical mass.
Sebastian F. Hönig, Darach Watson, Makoto Kishimoto et al. | An impenetrable barrier to ultrarelativistic electrons in the Van Allen radiation belts
Analysis of data obtained by probe spacecraft shows that ultrarelativistic electrons in the Van Allen radiation belts are prevented from entering a sharply defined region around the Earth, possibly owing to a combination of slow natural inward diffusion and pitch angle scattering.
D. N. Baker, A. N. Jaynes, V. C. Hoxie et al. | Metallization of vanadium dioxide driven by large phonon entropy
X-ray and neutron scattering measurements and ab initio molecular dynamics calculations show that the transition from an insulating phase to a metallic phase in vanadium dioxide is driven primarily by the entropic effects of soft anharmonic lattice vibrations, or phonons, which stabilize the metallic phase.
John D. Budai, Jiawang Hong, Michael E. Manley et al. | Passive radiative cooling below ambient air temperature under direct sunlight
A multilayer photonic structure is described that strongly reflects incident sunlight while emitting heat selectively through an atmospheric transparency window to outer space; this leads to passive cooling under direct sunlight of 5 degrees Celsius below ambient air temperature, which has potential applications in air-conditioning and energy efficiency.
Aaswath P. Raman, Marc Abou Anoma, Linxiao Zhu et al. | Design and fabrication of memory devices based on nanoscale polyoxometalate clusters
Flash memories are essential for modern electronics; here a selenium-templated polyoxometalate is used to engineer new metal–oxide–semiconductor devices.
Christoph Busche, Laia Vilà-Nadal, Jun Yan et al. | Evolution and forcing mechanisms of El Niño over the past 21,000 years
A simulation of the evolution of El Niño Southern Oscillation in the past 21,000 years in a state-of-the-art climate model shows the complex response mechanisms of El Niño to external climate forcings and poses further challenges to our understanding and projection of El Niño in the future.
Zhengyu Liu, Zhengyao Lu, Xinyu Wen et al. | Multiplex single-molecule interaction profiling of DNA-barcoded proteins
Single-molecular-interaction-sequencing involves attaching DNA barcodes to proteins, assaying these barcoded proteins en masse in an aqueous solution, followed by immobilization in a polyacrylamide film and amplifying and analysing the barcoding DNAs—the method allows for precise protein quantification and simultaneous interrogation of molecular binding affinity and specificity.
Liangcai Gu, Chao Li, John Aach et al. | MPDL3280A (anti-PD-L1) treatment leads to clinical activity in metastatic bladder cancer
The results of a clinical phase I study in metastatic urothelial bladder cancer treated with the MPDL3280A antibody show that expression of PD-L1 on tumour-infiltrating immune cells is relevant for the therapeutic response.
Thomas Powles, Joseph Paul Eder, Gregg D. Fine et al. | Predictive correlates of response to the anti-PD-L1 antibody MPDL3280A in cancer patients
Clinical and correlative biomarker results from a phase 1 clinical trial in patients with different solid tumours are presented; the findings indicate that PD-L1 expression on tumour-infiltrating immune cells is associated with clinical response to MPDL3280A (anti-PD-L1).
Roy S. Herbst, Jean-Charles Soria, Marcin Kowanetz et al. | PD-1 blockade induces responses by inhibiting adaptive immune resistance
The dynamics of T-cell responses are investigated in tumour tissue from patients with advanced melanoma who were treated with a PD-1-blocking monoclonal antibody, revealing that clinical efficacy of the treatment correlates with increased frequencies of pre-existing CD8+ T cells and PD-1 and PD-L1 expression.
Paul C. Tumeh, Christina L. Harview, Jennifer H. Yearley et al. | Predicting immunogenic tumour mutations by combining mass spectrometry and exome sequencing
A combination of genome-wide exome and transcriptome analysis, mass spectrometry and computational structural modelling are used here to identify immunogenic neo-antigens in two mouse tumour cancer cell lines; mice vaccinated with predicted immunogenic peptides yielded therapeutically useful cytotoxic T-lymphocyte responses.
Mahesh Yadav, Suchit Jhunjhunwala, Qui T. Phung et al. | Checkpoint blockade cancer immunotherapy targets tumour-specific mutant antigens
A carcinogen-induced mouse tumour model is used here to show that mutant tumour-specific antigens are targets for CD8+ T-cell responses, mediating tumour regression after checkpoint blockade immunotherapy, and that these antigens can be used effectively in therapeutic vaccines; this advance potentially opens the door to personalized cancer vaccines.
Matthew M. Gubin, Xiuli Zhang, Heiko Schuster et al. | Histone H2A.Z subunit exchange controls consolidation of recent and remote memory
The authors identify a specific histone variant as a memory-suppressor that is initially reduced in expression within the hippocampus during memory formation; as a memory is consolidated to the cortex, reduced histone association with specific plasticity genes is observed, promoting stabilization of the memory.
Iva B. Zovkic, Brynna S. Paulukaitis, Jeremy J. Day et al. | Epigenetic reprogramming that prevents transgenerational inheritance of the vernalized state
The Arabidopsis thaliana floral repressor FLC is epigenetically silenced by prolonged cold in a process called vernalization and then is reactivated before the completion of seed development; a histone demethylase, ELF6, is now shown to be involved in reactivating FLC in reproductive tissues, allowing the resetting of FLC expression and thus the requirement for vernalization in each generation.
Pedro Crevillén, Hongchun Yang, Xia Cui et al. | A structure-based mechanism for tRNA and retroviral RNA remodelling during primer annealing
To prime reverse transcription of Moloney murine leukaemia virus, a transfer RNA molecule must bind two regions of the retroviral RNA, the primer binding site (PBS) and primer activation signal within the U5-PBS; here, the NMR structures of the U5-PBS RNA and tRNA primer are solved, with and without the retroviral nucleocapsid protein, which remodels these regions.
Sarah B. Miller, F. Zehra Yildiz, Jennifer A. Lo et al. | | | | |
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