Research articles

In situ measurement of O₂ in the coma of comet 67P/Churyumov–Gerasimenko shows local abundances ranging from one per cent to ten per cent relative to H₂O; the spatial and temporal uniformity of the O₂/H₂O ratio suggests that primordial O₂ was incorporated into the nucleus during the comet’s formation.

Salamanders are the only tetrapod that can fully regenerate their limbs and tail, a capacity that might be linked to their unique preaxial mode of limb development; here, data from fossils reveal the existence of preaxial polarity in various amphibians from the Carboniferous and Permian periods, suggesting that salamander-like regeneration is an ancient feature of tetrapods that was subsequently lost at least once in the lineage leading to amniotes.

The X-ray crystal structure of influenza C virus polymerase, captured in a closed, pre-activation confirmation, is solved at 3.9 Å resolution; comparison with previous RNA-bound structures reveals large conformational changes associated with RNA binding and activation, and illustrates the notable flexibility of the influenza virus RNA polymerase.

Two flexible metal-organic frameworks are presented as solid adsorbents for methane that undergo reversible phase transitions at specific methane pressures, enabling greater storage capacities of usable methane than have been achieved previously, while also providing internal heat management of the system.

This study visualizes the interior of a dsRNA virus using cryo-electron microscopy, revealing the organization of the genome of cytoplasmic polyhedrosis virus together with its transcriptional enzyme complex in both quiescent and transcribing states.

Fungal pathogens reorient hyphal growth towards their plant hosts in response to chemical signals; here, directed growth of the plant pathogen Fusarium oxysporum towards the roots of the tomato plant is shown to be triggered by class III peroxidases secreted by the tomato plant, with the fungal response requiring a sex pheromone receptor.

Treating ovarian cancer in mouse models with inhibitors for the epigenetic regulators EZH2 and DNMT1 increases the expression of the inflammatory chemokines CXCL9 and CXCL10, resulting in enhanced tumour infiltration by effector T cells, and slowed tumour progression.

The structure of the Cas1–Cas2 complex bound to a protospacer sequence illustrates how foreign DNA is captured and measured by bacterial proteins in preparation for integration into CRISPR loci.

Chemical methods for adding carbon-based or nitrogen-based functional groups to alkenes are well established, but strategies for adding both to the same double bond have limitations; here, a method for the carboamination of alkenes at the same double bond is described.

The atmospheres of white dwarfs often contain elements heavier than helium, even though these elements would be expected to settle into the stars’ interiors; observations of the white dwarf WD 1145+017 suggest that disintegrating rocky bodies are orbiting the star, perhaps contributing heavy elements to its atmosphere.

A Bell experiment that is ‘loophole’ free—leaving no room for explanations based on experimental imperfections—reveals a statistically significant conflict with local realism

The authors trained mice to attend to or suppress vision based on behavioral context and show, through novel and established techniques, that changes in visual gain rely on tunable feedforward inhibition of visual thalamus via innervating thalamic reticular neurons; these findings introduce a subcortical model of attention in which modality-specific thalamic reticular subnetworks mediate top-down and context-dependent control of sensory selection.

At the initiation of DNA double-strand break repair, a number of ubiquitylation events occur; here, the RNF8 ubiquitin E3 ligase and the ubiquitin-conjugating E2 enzyme, UBC13, are shown to primarily modify H1-type linker histones, via a K63 linkage.

Economic productivity is shown to peak at an annual average temperature of 13 °C and decline at high temperatures, indicating that climate change is expected to lower global incomes more than 20% by 2100.

Marine anaerobic methanotrophic archaea and sulfate-reducing bacteria connect by pili-like nanowires, suggesting that direct interspecies exchange of electrons could be a fundamental mechanism in the anaerobic oxidation of methane.

High-resolution X-ray spectra reveal highly ionized X-ray gas flows in a nearby tidal disruption event, ASASSN-14li, near to the black hole of the galaxy PGC 043234.

Charcot–Marie–Tooth diseases are hereditary peripheral neuropathies for which there are currently no effective therapies; here the type 2D subtype of these diseases is shown to be caused by mutations impeding a signalling pathway necessary for motor neuron survival.

Experiments, asymptotic theory and computer simulations of wall-bounded shear flow uncover a bifurcation scenario that explains the transition from localized turbulent patches to fully turbulent flow.

This study finds that the Hippo pathway is essential for gut epithelial regeneration and tumour initiation; the Hippo component Yap holds off differentiation of intestinal stem cells to Paneth cells to promote a survival and self-renewal regenerative program through activation of the Egfr pathway.

An affordable, safe, and scalable battery system is presented, which uses organic polymers as the charge-storage material in combination with inexpensive dialysis membranes and an aqueous sodium chloride solution as the electrolyte.