The French government must mitigate the risks in its legal imposition of vaccinations by promoting more coherent and proactive vaccine policies.
The country’s research could soon dominate the world stage, but pitfalls lie in wait.
Republican politicians caught unfairly altering electoral districts thanks to computer algorithm.
Experiment smashes electrons into positrons to search for unseen particles and problems with overarching physics framework.
Court temporarily revives protections for some unauthorized immigrants as Trump and Congress clash over policy reform.
Engineered organisms that cannot breed with wild counterparts could prevent transgenic plants from spreading genes to unmodified crops and weeds, and battle pests.
The country’s ambition to become the global leader in artificial intelligence will require a large, highly skilled workforce.
Experiment shows how spacecraft could use stellar signals to navigate in deep space without human instruction.
The womb was thought to be sterile, but some scientists argue that it’s where the microbiome begins.
The world is lit at night like never before, and ecologists are assessing the damage.
News & Views
Mice can learn to overcome their naturally aggressive approach to conflict resolution, instead adopting a cooperative
strategy. This discovery provides a simple animal model in which to investigate a complex social behaviour.
Epidemic strains of the bacterium Clostridium difficile have now been found to grow on unusually low levels of the food additive trehalose, providing a possible explanation for C. difficile outbreaks since 2001.
Compounds have been made that activate only the G-protein signalling pathway when bound to the μ-opioid receptor — the target of opioid pain relievers. These compounds lack one of the main side effects of currently used opioids.
The sensitivity of Earth’s climate to atmospheric carbon dioxide levels is a big unknown in predicting future global warming. A compelling analysis suggests that we can rule out high estimates of this sensitivity.
Evidence has now been found that ribosomes — the cell’s translational apparatus — can pass beyond the main protein-coding region of messenger RNAs to form ‘traffic jams’ that inhibit protein expression.
Two hypervirulent ribotypes of the enteric pathogen Clostridium difficile, RT027 and RT078, have independently acquired unique mechanisms to metabolize low concentrations of the disaccharide trehalose, suggesting a correlation between the emergence of these ribotypes and the widespread adoption of trehalose in the human diet.
Cryo-EM structures of Pol III preinitiation complexes are presented, comprising Pol III and the transcription factor TFIIIB bound to a natural promoter in different functional states.
Detailed structures of yeast RNA polymerase III and its initiation complex shed light on how the transcription of essential non-coding RNAs begins and allow comparisons with other RNA polymerases.
The star formation histories of galaxies, as encapsulated in their integrated optical spectra, depend on the mass of the black holes present at their centres.
Convection plays a major part in many astrophysical processes, including energy transport, pulsation, dynamos and winds on evolved stars, in dust clouds and on brown dwarfs. Most of our knowledge about stellar convection has come from studying the Sun: about two million convective cells with typical sizes of around 2,000 kilometres across are present on the surface of the Sun—a phenomenon known as granulation. But on the surfaces of giant and supergiant stars there should be only a few large (several tens of thousands of times larger than those on the Sun) convective cells, owing to low surface gravity. Deriving the characteristic properties of convection (such as granule size and contrast) for the most evolved giant and supergiant stars is challenging because their photospheres are obscured by dust, which partially masks the convective patterns. These properties can be inferred from geometric model fitting, but this indirect method does not provide information about the physical origin of the convective cells. Here we report interferometric images of the surface of the evolved giant star π1 Gruis, of spectral type S5,7. Our images show a nearly circular, dust-free atmosphere, which is very compact and only weakly affected by molecular opacity. We find that the stellar surface has a complex convective pattern with an average intensity contrast of 12 per cent, which increases towards shorter wavelengths. We derive a characteristic horizontal granule size of about 1.2 × 1011 metres, which corresponds to 27 per cent of the diameter of the star. Our measurements fall along the scaling relations between granule size, effective temperature and surface gravity that are predicted by simulations of stellar surface convection.
Droplets covered with surfactants that respond to multiple stimuli can assemble into hierarchical assemblies or non-spherical, patchy structures, mimic systems of mechanical gears, and even harbour sequences of chemical reactions.
Equilibrium climate sensitivity—which remains the largest uncertainty in climate projections—is constrained to a ‘likely’ range of 2.2–3.4 K by taking into account the variability of global temperature about long-term historical warming.
Deep-ocean O2 concentrations over the past 3.5 billion years are estimated using the oxidation state of iron in submarine basalts and indicate that deep-ocean oxygenation occurred in the Phanerozoic.
Assessment of the impact of armed conflict on large herbivores in Africa between 1946 and 2010 reveals that high conflict frequency is an important predictor of wildlife population declines.
Travel time to cities in 2015 is quantified in a high-resolution global map that will be useful for socio-economic policy design and conservation research.
In hybrid inviability between Xenopus laevis and Xenopus tropicalis, genomic regions on two X. laevis chromosomes are incompatible with the X. tropicalis cytoplasm and are mis-segregated during mitosis, leading to unbalanced gene expression at the maternal to zygotic transition, followed by cell-autonomous catastrophic embryo death.
The cells of multicellular organisms receive extracellular signals using surface
receptors. The extracellular domains (ECDs) of cell surface receptors function as
interaction platforms, and as regulatory modules of receptor activation. Understanding how interactions between ECDs produce
signal-competent receptor complexes is challenging because of their low biochemical
tractability. In plants, the discovery of ECD interactions is
complicated by the massive expansion of receptor families, which creates tremendous
potential for changeover in receptor interactions. The largest of
these families in Arabidopsis thaliana consists of 225 evolutionarily related
leucine-rich repeat receptor kinases (LRR-RKs), which function in
the sensing of microorganisms, cell expansion, stomata development and stem-cell
maintenance. Although the principles that govern LRR-RK
signalling activation are emerging, the systems-level
organization of this family of proteins is unknown. Here, to address this, we
investigated 40,000 potential ECD interactions using a sensitized high-throughput
interaction assay, and produced an LRR-based cell surface
interaction network (CSILRR) that consists of 567 interactions. To
demonstrate the power of CSILRR for detecting biologically relevant
interactions, we predicted and validated the functions of uncharacterized LRR-RKs in
plant growth and immunity. In addition, we show that CSILRR operates
as a unified regulatory network in which the LRR-RKs most crucial for its overall
structure are required to prevent the aberrant signalling of receptors that are
several network-steps away. Thus, plants have evolved LRR-RK networks to process
extracellular signals into carefully balanced responses.
Immune checkpoint blockade with anti-PD-1 or anti-PD-L1 agents produces a high response rate in patients with desmoplastic melanoma.
REV-ERBs, nuclear hormone receptors that regulate transcription as part of the circadian clock cell machinery, inhibit autophagy and lipogenesis in premalignant and malignant cells and impair tumour growth in vivo.
A regulatory mechanism that limits the number of complete protein molecules that can be synthesized from a single mRNA molecule of the human AMD1 gene encoding adenosylmethionine decarboxylase 1.
The crystal structure of a channel-forming O-antigen polysaccharide ABC transporter suggests a novel biopolymer translocation mechanism.