| |
Evolution: Fitness tracking for adapting populations
A method for tracking the descendants of hundreds of thousands of yeast cells in an evolving population reveals that thousands of individuals contribute to early increases in population-wide fitness. |
Cell signalling: Disarming Wnt
The secreted enzyme Notum has been found to inhibit the Wnt signalling pathway through removal of a lipid that is linked to the Wnt protein and that is required for activation of Wnt receptor proteins. |
A motor cortex circuit for motor planning and movement
During movement preparation, motor cortical neuronal subpopulations that project to downstream motor areas are more selective for the direction of upcoming movement than those that project to other cortical targets, especially immediately before movement, emphasizing the need to interpret complex neuronal responses measured during behaviour in the context of hierarchically organized cortical circuits. |
A gp130–Src–YAP module links inflammation to epithelial regeneration
This study demonstrates the activation of a STAT3-independent healing pathway in response to mucosal injury which involves the co-receptor for IL-6 cytokines gp130 and downstream effectors Src, Yes, YAP and Notch. |
Notum deacylates Wnt proteins to suppress signalling activity
The biochemical activity of Notum as a carboxylesterase that removes an essential lipid moiety from Wnt proteins is uncovered; the interaction of Notum with glypicans is required to ensure localization at the cell surface, and Notum may provide a new target for therapeutic development in diseases with defective Wnt signalling. |
Quantitative evolutionary dynamics using high-resolution lineage tracking
Random DNA barcodes were used to simultaneously track hundreds of thousands of lineages in large cell populations, revealing deterministic dynamics early in their evolution. |
NIK1-mediated translation suppression functions as a plant antiviral immunity mechanism
A new mechanism that plants use to combat begomoviruses—one of the most pathogenic groups of plant viruses, causing severe disease in major crops worldwide—is uncovered: plants inhibit the transcription of genes associated with the translational apparatus, thus causing a general reduction in protein synthesis. |
Decrease in CO2 efflux from northern hardwater lakes with increasing atmospheric warming
Atmospheric warming may reduce CO2 emissions from hardwater lakes by reducing the duration of ice cover, increasing lake water pH and favouring CO2 sequestration. |
Differential DNA mismatch repair underlies mutation rate variation across the human genome
An analysis of how regional mutation rates vary across 652 tumours identifies variable DNA mismatch repair as the basis of the characteristic regional variation in mutation rates seen across the human genome; the results show that differential DNA repair, rather than differential mutation supply, is likely to be the primary cause of this variation. |
Horizontal membrane-intrinsic α-helices in the stator a-subunit of an F-type ATP synthase
Electron cryomicroscopy of a complete mitochondrial ATP-synthase dimer reveals the elusive structure of the essential a-subunit. |
Observation of antiferromagnetic correlations in the Hubbard model with ultracold atoms
Ultracold atomic gases in optical lattices potentially offer simulations of condensed-matter phenomena beyond what theory and computations can access; compensated optical lattice techniques applied to the Hubbard model now enable unprecedented low temperatures to be reached for fermions — only 1.4 times that of the antiferromagnetic phase transition, approaching the limits of present modelling techniques. |
Dietary emulsifiers impact the mouse gut microbiota promoting colitis and metabolic syndrome
Emulsifying agents, which are common food additives in the human diet, induce low-grade inflammation and obesity/metabolic syndrome in mice, suggesting that further investigation into the potential impact of dietary emulsifiers on the gut microbiota and human heath are warranted. |
Observational determination of surface radiative forcing by CO2 from 2000 to 2010
Empirical evidence for the effect of rising atmospheric carbon dioxide levels on Earth’s surface energy balance is presented: the increase in surface radiative forcing from 2000 to 2010 measured at two sites is directly attributable to the increase in atmospheric carbon dioxide over that decade and agrees with model results. |
Structure of the E. coli ribosome–EF-Tu complex at <3 Å resolution by Cs-corrected cryo-EM
A single particle cryo-EM structure of the 70S ribosome in complex with the elongation factor Tu breaks the 3 Å resolution barrier of the technique and locally exceeds the resolution of previous crystallographic studies, revealing all modifications in rRNA and explaining their roles in ribosome function and antibiotic binding. |
| Erratum: A new antibiotic kills pathogens without detectable resistance |
| Corrigendum: OSCA1 mediates osmotic-stress-evoked Ca2+ increases vital for osmosensing in Arabidopsis |
|
Whole genomes redefine the mutational landscape of pancreatic cancer
A whole-genome sequencing analysis of 100 pancreatic ductal adenocarcinomas has discovered known and newly identified genetic drivers of pancreatic cancer; these genetic alterations can be classified into four subtypes, which raises the possibility of improved targeting of clinical treatments.
Nicola Waddell, Marina Pajic, Ann-Marie Patch et al. |
Lagging-strand replication shapes the mutational landscape of the genome
The emRiboSeq sequencing method is used to track polymerase activity genome-wide in vivo; despite Okazaki fragment processing, DNA synthesized by error-prone polymerase-α (Pol-α) is retained in vivo and comprises ∼1.5% of the genome, establishing Pol-α as an important source of genomic variability and providing a mechanism for site-specific variation in nucleotide substitution rates.
Martin A. M. Reijns, Harriet Kemp, James Ding et al. |
Crystal structure of the V(D)J recombinase RAG1–RAG2
The crystal structure of the RAG1–RAG2 heterotetramer forms a Y-shaped structure, with each arm containing a RAG1–RAG2 heterodimer; the overall structure is reminiscent of hairpin-forming transposases, attesting to its evolutionary history as a specialized form of a transposition activity.
Min-Sung Kim, Mikalai Lapkouski, Wei Yang et al. |
|
An ultraluminous quasar with a twelve-billion-solar-mass black hole at redshift 6.30
Observations of an ultraluminous quasar, SDSS J010013.02+280225.8, at redshift z=6.30 show that the object has an optical and near-infrared luminosity a few times greater than those of previously known quasars at z > 6; the black hole that drives the quasar has a mass about 12 billion times that of the Sun.
Xue-Bing Wu, Feige Wang, Xiaohui Fan et al. |
Quantum teleportation of multiple degrees of freedom of a single photon
The quantum teleportation of composite quantum states of a single photon encoded in both spin and orbital angular momentum is achieved, with a teleportation fidelity above the classical limit, by quantum non-demolition measurement assisted discrimination of the Bell states describing the entanglement of the two degrees of freedom.
Xi-Lin Wang, Xin-Dong Cai, Zu-En Su et al. |
Role of TP53 mutations in the origin and evolution of therapy-related acute myeloid leukaemia
Somatic TP53 mutations are highly prevalent in therapy-related acute myeloid leukaemia and myelodysplastic syndrome, which arise as complications of cytotoxic chemotherapy or radiotherapy; although it was believed that these TP53 mutations are directly induced by cytotoxic therapy, new data indicate that they predate cytotoxic therapy and that haematopoietic progenitors harbouring these pre-existing mutations may selectively expand after exposure to chemotherapy or radiotherapy.
Terrence N. Wong, Giridharan Ramsingh, Andrew L. Young et al. |
Enhancer––core-promoter specificity separates developmental and housekeeping gene regulation
The core promoters of developmental and housekeeping genes are shown to have distinct specificities for different enhancer sequences in Drosophila, and this specificity separates developmental and housekeeping gene regulatory programs across the genome.
Muhammad A. Zabidi, Cosmas D. Arnold, Katharina Schernhuber et al. |
Tissue-resident macrophages originate from yolk-sac-derived erythro-myeloid progenitors
To determine the origin of adult tissue-resident macrophages, a mouse lineage tracing study has revealed that these cells derive from erythro-myeloid progenitors in the yolk sac that are distinct from fetal and adult haematopoietic stem cells.
Elisa Gomez Perdiguero, Kay Klapproth, Christian Schulz et al. |
Experimentally induced innovations lead to persistent culture via conformity in wild birds
How socially transmitted behaviours spread and persist is shown in a wild animal population, revealing an effect of social conformity.
Lucy M. Aplin, Damien R. Farine, Julie Morand-Ferron et al. |
Dynamically reconfigurable complex emulsions via tunable interfacial tensions
The temperature-sensitive miscibility of hydrocarbon, silicone and fluorocarbon liquids is used to establish a one-step method of making three- and four-phase complex emulsions with highly controllable morphologies that can be alternated between encapsulated and Janus configurations by varying the balance of interfacial tensions.
Lauren D. Zarzar, Vishnu Sresht, Ellen M. Sletten et al. |
An extremely high-altitude plume seen at Mars’ morning terminator
Examination of amateur observations of Mars shows atmospheric plumes 200 to 250 kilometres high that are observed in the morning but not in the evening over a period of more than a week; our current understanding of Martian atmospheric dynamics and plume formation cannot account for the creation of such enormous plumes.
A. Sánchez-Lavega, A. García Muñoz, E. García-Melendo et al. |
Human-level control through deep reinforcement learning
An artificial agent is developed that learns to play a diverse range of classic Atari 2600 computer games directly from sensory experience, achieving a performance comparable to that of an expert human player; this work paves the way to building general-purpose learning algorithms that bridge the divide between perception and action.
Volodymyr Mnih, Koray Kavukcuoglu, David Silver et al. |
Evolution of the new vertebrate head by co-option of an ancient chordate skeletal tissue
A tissue with many of the defining features of vertebrate cellular cartilage is shown to form transiently in larvae of the invertebrate chordate amphioxus, indicating that the origin of the vertebrate head skeleton depended not on evolution of a new skeletal tissue, as is commonly thought, but on the spread of this tissue throughout the head.
David Jandzik, Aaron T. Garnett, Tyler A. Square et al. |
Fundamental properties of unperturbed haematopoiesis from stem cells in vivo
Inducible genetic labelling of haematopoietic stem cells (HSCs) and linked mathematical modelling show that at least 30% of all HSCs are productive, and that adult haematopoiesis is largely sustained by ‘short-term’ downstream stem cells that operate near self-renewal in the steady state; HSC fate mapping provides a quantitative model for better understanding of HSC functions in health and disease.
Katrin Busch, Kay Klapproth, Melania Barile et al. |
N6-methyladenosine-dependent RNA structural switches regulate RNA–protein interactions
The binding motifs for many RNA-binding proteins are normally buried within structured regions; now, the N6-methyladenosine modification is shown to act as a switch to remodel these regions, expose the motif, and thereby facilitate binding of RNA-binding proteins.
Nian Liu, Qing Dai, Guanqun Zheng et al. |
|
| |
|
댓글 없음:
댓글 쓰기