Ethane and propane rises have been traced to the global fossil-fuel industry. Now governments need to act.
A set of guidelines could trigger positive action.
Reporting summaries help authors to provide important details before review.
Wildlife traffickers seek body parts from protected species to satisfy consumers in China.
Pension changes spur more than 40,000 university academics to walk out on research activities, conferences and lectures.
Education bills would allow people who live in the state to review and recommend instructional materials to be used in schools.
Researchers in India hope that institute's finding will motivate other academic organizations to confront harassment.
Therapies to prevent infection are advancing in a crowded field.
Publishers would need to join forces to apply image-checking software across the literature.
Neuroscientists are getting excited about non-invasive procedures to tune the brain’s natural oscillations.
News & Views
Researchers have produced high-resolution maps of childhood growth failure and educational attainment across Africa
between 2000 and 2015, to assess progress and guide policy decisions in public health.
Quantum logic gates based on trapped ions perform more accurately than solid-state devices, but have been slower. Experiments show how trapped-ion gates can be sped up, as is needed to realize a quantum computer.
A population of progenitor cells in the midgut of fruit flies undergoes differentiation in response to mechanical force. This finding marks the first time that such a phenomenon has been reported in vivo.
Exotic states of matter called topological superconductors have potential applications in quantum computing, but have been difficult to produce in more than one dimension. A way of overcoming this limitation has now been found.
Charged groups on protein surfaces often take part in molecular interactions. Two unstructured proteins have been found to use charge complementarity to form a tight complex that has biologically useful kinetic properties.
An experiment to estimate when stars began to form in the Universe suggests that gas temperatures just before stars appeared had fallen well below predicted limits, and that dark matter is not as shadowy as was thought.
Geospatial estimates of child growth failure in Africa provide a baseline for measuring progress and a precision public health platform to target interventions to those populations with the greatest need.
Local-level analyses show that, despite marked progress in educational attainment from 2000 to 2015 across Africa, substantial differences persist between locations and sexes that have widened in many countries.
Single-cell transcriptomics, fate assays and a computational theory enable prediction of cell fates during haematopoiesis, discovery of regulators of erythropoiesis and reveal coupling between the erythroid, basophil and mast cell fates.
A high-affinity complex of histone H1 and prothymosin-α reveals an unexpected interaction mechanism, where the large opposite net charge enables the two proteins to remain highly disordered even in the complex.
The 21-cm absorption profile is detected in the sky-averaged radio spectrum, but is much stronger than predicted, suggesting that the primordial gas might have been cooler than predicted.
The large absorption of the 21-centimetre transition of hydrogen around redshift 20 is explained by radiation from the first stars, combined with excess cooling of the cosmic gas caused by baryon–dark matter scattering.
Fast and high-fidelity two-qubit logic gates are demonstrated by using amplitude-shaped laser pulses to ensure that the gate operation is insensitive to the optical phase of the pulses.
Ultrashort mid-infrared laser pulses can drive atoms far from their equilibrium positions in LiNbO3, exciting high phonon harmonics and providing a way to map the interatomic potential.
A scalable process is described for fabricating skin-like electronic circuitry that can be bent and stretched while retaining desirable electronic functionality.
Active volcanic hotspots can tap into domains in Earth’s deep interior that were formed more than two billion years ago. High-precision data on variability in tungsten isotopes have shown that some of these domains resulted from differentiation events that occurred within the first fifty million years of Earth history. However, it has not proved easy to resolve analogous variability in neodymium isotope compositions that would track regions of Earth’s interior whose composition was established by events occurring within roughly the first five hundred million years of Earth history. Here we report 142Nd/144Nd ratios for Réunion Island igneous rocks, some of which are resolvably either higher or lower than the ratios in modern upper-mantle domains. We also find that Réunion 142Nd/144Nd ratios correlate with helium-isotope ratios (3He/4He), suggesting parallel behaviour of these isotopic systems during very early silicate differentiation, perhaps as early as 4.39 billion years ago. The range of 142Nd/144Nd ratios in Réunion basalts is inconsistent with a single-stage differentiation process, and instead requires mixing of a conjugate melt and residue formed in at least one melting event during the Hadean eon, 4.56 billion to 4 billion years ago. Efficient post-Hadean mixing nearly erased the ancient, anomalous 142Nd/144Nd signatures, and produced the relatively homogeneous 143Nd/144Nd composition that is characteristic of Réunion basalts. Our results show that Réunion magmas tap into a particularly ancient, primitive source compared with other volcanic hotspots, offering insight into the formation and preservation of ancient heterogeneities in Earth’s interior.
Analyses of a global dataset of plant root traits identify an ancestral conservative strategy based on thick roots and mycorrhizal symbiosis, and an evolutionarily more-recent opportunistic strategy of thin roots that efficiently use photosynthetic carbon for soil exploration.
Circadian clocks coordinate behaviour, physiology and metabolism with
Earth’s diurnal cycle. These clocks entrain to both
light and temperature cycles, and daily environmental temperature
oscillations probably contribute to human sleep patterns. However,
the neural mechanisms through which circadian clocks monitor environmental
temperature and modulate behaviour remain poorly understood. Here we elucidate how
the circadian clock neuron network of Drosophila melanogaster processes
changes in environmental temperature. In vivo calcium-imaging techniques
demonstrate that the posterior dorsal neurons 1 (DN1ps), which are a
discrete subset of sleep-promoting clock neurons, constantly monitor
modest changes in environmental temperature. We find that these neurons are acutely
inhibited by heating and excited by cooling; this is an unexpected result when
considering the strong correlation between temperature and light, and the fact that
light excites clock neurons. We demonstrate that the
DN1ps rely on peripheral thermoreceptors located in the chordotonal
organs and the aristae. We also show that the
DN1ps and their thermosensory inputs are required for the normal
timing of sleep in the presence of naturalistic temperature cycles. These results
identify the DN1ps as a major gateway for temperature sensation into the
circadian neural network, which continuously integrates temperature changes to
coordinate the timing of sleep and activity.
Somatic stem cells constantly adjust their self-renewal and lineage commitment by
integrating various environmental cues to maintain tissue homeostasis. Although
numerous chemical and biological signals have been identified that regulate
stem-cell behaviour, whether stem cells can directly sense mechanical signals in
vivo remains unclear. Here we show that mechanical stress
regulates stem-cell differentiation in the adult Drosophila midgut through
the stretch-activated ion channel Piezo. We find that Piezo is specifically
expressed in previously unidentified enteroendocrine precursor cells, which have
reduced proliferation ability and are destined to become enteroendocrine cells. Loss
of Piezo activity reduces the generation of enteroendocrine cells in the
adult midgut. In addition, ectopic expression of Piezo in all stem cells
triggers both cell proliferation and enteroendocrine cell differentiation. Both the
Piezo mutant and overexpression phenotypes can be rescued by manipulation
of cytosolic Ca2+ levels, and increases in cytosolic
Ca2+ resemble the Piezo overexpression phenotype, suggesting that
Piezo functions through Ca2+ signalling. Further studies suggest that
Ca2+ signalling promotes stem-cell proliferation and
differentiation through separate pathways. Finally, Piezo is required for
both mechanical activation of stem cells in a gut expansion assay and the increase
of cytosolic Ca2+ in response to direct mechanical stimulus in a gut
compression assay. Thus, our study demonstrates the existence of a specific group of
stem cells in the fly midgut that can directly sense mechanical signals through
A sequence that is frequently found in Alu elements drives the localization of some long RNAs to the nucleus in human cells.
Oncogene activation results in firing of ectopic origins of replication within transcribed genes, resulting in replication stress and genome instability.
The structure of huntingtin in complex with an interactor is determined to an overall resolution of 4 Å, paving the way for improved understanding of the cellular functions of this protein.
The class B glucagon-like peptide-1 (GLP-1) G protein-coupled receptor is a major target for the treatment of type 2 diabetes and obesity. Endogenous and mimetic GLP-1 peptides exhibit biased agonism—a difference in functional selectivity—that may provide improved therapeutic outcomes. Here we describe the structure of the human GLP-1 receptor in complex with the G protein-biased peptide exendin-P5 and a Gαs heterotrimer, determined at a global resolution of 3.3 Å. At the extracellular surface, the organization of extracellular loop 3 and proximal transmembrane segments differs between our exendin-P5-bound structure and previous GLP-1-bound GLP-1 receptor structure. At the intracellular face, there was a six-degree difference in the angle of the Gαs–α5 helix engagement between structures, which was propagated across the G protein heterotrimer. In addition, the structures differed in the rate and extent of conformational reorganization of the Gαs protein. Our structure provides insights into the molecular basis of biased agonism.