| | Epigenetics: An elusive DNA base in mammals
The discovery of a modified version of the base adenine, known as N6-methyladenine, in mouse DNA puts paid to the theory that cytosine derivatives are the only modified bases in mammals. | Animal behaviour: Some begging is actually bragging
A meta-analysis of 143 bird species finds huge variation in parental responses to chicks' begging signals, and shows that parental strategies depend on environmental factors, such as the predictability and quality of food supplies. | Regeneration: Not everything is scary about a glial scar
After spinal-cord injury, cells called astrocytes form a scar that is thought to block neuronal regeneration. The finding that the scar promotes regrowth of long nerve projections called axons challenges this long-held dogma. | Microbiology: Fungus produces a toxic surprise
A protein fragment released by filaments of the fungus Candida albicans destroys host cells. This is the first demonstration that human fungal pathogens other than moulds can release toxic peptides. | Island biogeography: Shaped by sea-level shifts
An analysis of changes in island topography and climate that have occurred since the last glacial maximum 21,000 years ago shows how sea-level change has influenced the current biodiversity of oceanic islands. | Astrocyte scar formation aids central nervous system axon regeneration
Sustained delivery of axon-specific growth factors not typically present in spinal cord lesions allows for robust axonal regrowth only if the astrocytic scar is present—a result that questions the prevailing dogma and suggests that astrocytic scarring aids rather than prevents central nervous system axon regeneration post injury. | Candidalysin is a fungal peptide toxin critical for mucosal infection
This study identifies a cytolytic peptide toxin in the opportunistic human fungal pathogen Candida albicans—the peptide is both a crucial virulence factor that permeabilizes the host cell plasma membrane and a key signal that triggers a host danger response pathway. | DNA methylation on N6-adenine in mammalian embryonic stem cells
The prevalence of N6-adenine DNA methylation in mammals was previously unknown; this study reveals that N6-methyladenine can be found in mouse embryonic stem cells, especially at subfamilies of young (<1.5 million years old) LINE-1 transposons. | A map of the large day–night temperature gradient of a super-Earth exoplanet
A longitudinal thermal brightness map of the super-Earth exoplanet 55 Cancri e reveals strong day–night temperature contrast, indicating inefficient heat redistribution consistent with 55 Cancri e either being devoid of atmosphere or having an optically thick atmosphere with heat recirculation confined to the planetary dayside. | Quantum hydrogen-bond symmetrization in the superconducting hydrogen sulfide system
Ab initio calculations are used to determine the contribution of quantum fluctuations to the crystal structure of the high-pressure superconducting phase of H3S and D3S; the quantum nature of the proton is found to fundamentally change the superconducting phase diagram of H3S. | Cerebral cavernous malformations arise from endothelial gain of MEKK3–KLF2/4 signalling
Gain of MEKK3 signalling is shown to cause cerebral cavernous malformations (CCMs) via activation of the target genes Klf2 and Klf4; endothelial-specific loss of MEKK3, KLF2 or KLF4 prevents lesion formation and lethality in a mouse CCM model. | Revised stratigraphy and chronology for Homo floresiensis at Liang Bua in Indonesia
New excavations in Liang Bua, where the remains of the ‘Hobbit’ (Homo floresiensis) were discovered, show that this diminutive human species used this cave between 190,000 and 50,000 years ago, and not until as recently as 12,000 years ago as previously interpreted; modern humans have been present in Australia since around 50,000 years ago, so whether Homo floresiensis survived long enough to witness the arrival of modern humans is still an open question. | Copper-catalysed enantioselective stereodivergent synthesis of amino alcohols
Here, a method is described by which to generate all possible stereoisomers of certain amino alcohols—a protocol that should see use in drug discovery and development, where it is important to determine the differing effects of stereoisomeric drug candidates. | Anatomy and function of an excitatory network in the visual cortex
Two-photon calcium imaging and electron microscopy were used to explore the relationship between structure and function in mouse primary visual cortex, showing that layer 2/3 neurons are connected in subnetworks, that pyramidal neurons with similar orientation selectivity preferentially form synapses with each other, and that neurons with similar orientation tuning form larger synapses; this study exemplifies functional connectomics as a powerful method for studying the organizational logic of cortical networks. | Mitochondrial ROS regulate thermogenic energy expenditure and sulfenylation of UCP1
Uncoupling protein 1 (UCP1)-dependent thermogenesis in brown adipose tissue is supported by a burst of mitochondrial reactive oxygen species upon cold exposure. | Structural basis of cohesin cleavage by separase
The crystal structures of the protease domain of separase are reported, showing how separase recognizes cohesin, and how phosphorylation of the cleavage site enhances separase activity. | Lypd8 promotes the segregation of flagellated microbiota and colonic epithelia
Lypd8 protein derived from intestinal epithelial cells binds to flagellated bacteria to reduce their motility, which limits the entry of Gram-negative bacteria into the inner colonic mucus and prevents invasion of colonic epithelia. | Late Quaternary climate change shapes island biodiversity
Relatively rapid changes in island area, isolation and connectivity observed since the Last Glacial Maximum have had measurable effects on present-day biodiversity, with formerly larger and less well connected islands having a greater number of endemic species. | | | | 
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| | | | | | | | | | | Contribution of Antarctica to past and future sea-level rise
Climate and ice-sheet modelling that includes ice fracture dynamics reveals that Antarctica could contribute more than a metre of sea-level rise by 2100 and more than 15 metres by 2500, if greenhouse gas emissions continue unabated.
Robert M. DeConto, David Pollard | Cullin–RING ubiquitin E3 ligase regulation by the COP9 signalosome
Much of the intracellular protein degradation in eukaryotes is controlled by cullin–RING ubiquitin ligases (CRLs), a vast class of enzymes which are regulated by the COP9 signalosome (CSN); structural characterization of CSN–N8CRL4A complexes by cryo-electron microscopy reveals an induced-fit mechanism of CSN activation triggered only by catalytically activated CRLs without bound substrate, explaining how CSN acts as a global regulator of CRLs.
Simone Cavadini, Eric S. Fischer, Richard D. Bunker et al. | Structure of promoter-bound TFIID and model of human pre-initiation complex assembly
A sub-nanometre resolution cryo-EM structure of human TFIID bound to TFIIA and core promoter DNA and a model of the TFIID-based pre-initiation complex.
Robert K. Louder, Yuan He, José Ramón López-Blanco et al. | | Nucleus accumbens D2R cells signal prior outcomes and control risky decision-making
Increased activity of dopamine receptor type-2 (D2R)-expressing cells in the nucleus accumbens of rats during a ‘decision’ period reflects a ‘loss’ outcome of the previous decision and predicts a subsequent safe choice; by artificially increasing the activity of D2R neurons during the decision period, risk-seeking rats could be converted to risk-avoiding rats.
Kelly A. Zalocusky, Charu Ramakrishnan, Talia N. Lerner et al. | Primary cilia are not calcium-responsive mechanosensors
Mechanosensation, if it originates in primary cilia, is not via calcium signalling.
M. Delling, A. A. Indzhykulian, X. Liu et al. | R-process enrichment from a single event in an ancient dwarf galaxy
It has long been debated whether elements heavier than zinc are formed continually, for example in core-collapse supernovae, or in rare events, such as neutron star mergers; here, studies of element abundances in a local ultrafaint dwarf galaxy provide evidence that these elements are formed during rare yet prolific stellar events.
Alexander P. Ji, Anna Frebel, Anirudh Chiti et al. | Measurement of the Earth tides with a MEMS gravimeter
A light-weight, low-cost microelectromechanical system gravimeter is presented with sensitivity and stability high enough to measure the elastic deformation of the Earth’s crust as a result of tidal forces, enabling many applications.
R. P. Middlemiss, A. Samarelli, D. J. Paul et al. | The conformational signature of β-arrestin2 predicts its trafficking and signalling functions
A series of intramolecular fluorescent FlAsH BRET reporters is used to monitor conformational changes in β-arrestin2 following activation of seven G-protein-coupled receptors (GPCRs), showing that different GPCRs produce distinct β-arrestin2 conformational signatures that correlate with the stability of the receptor–arrestin complex and the role of β-arrestin2 in activating or dampening downstream signalling events, which explains how different GPCRs can use a common effector for different purposes.
Mi-Hye Lee, Kathryn M. Appleton, Erik G. Strungs et al. | Bidirectional electromagnetic control of the hypothalamus regulates feeding and metabolism
Activation of glucose-sensing neurons in the ventromedial hypothalamic nucleus using radio waves or magnetic fields remotely and non-invasively in vivo increases plasma glucose and glucagon, and suppresses plasma insulin; conversely, remote inhibition of glucose-sensing neurons decreased blood glucose and increased plasma insulin.
Sarah A. Stanley, Leah Kelly, Kaamashri N. Latcha et al. | Soft surfaces of nanomaterials enable strong phonon interactions
A combined experimental and theoretical investigation of phononic properties in nanocrystal-based semiconductors reveals that unusually strong coupling between phonons and electrons originates from the mechanical softness of the surfaces of the nanocrystalline domains and sheds new light on their recombination in nanocrystal-based devices.
Deniz Bozyigit, Nuri Yazdani, Maksym Yarema et al. | Visualizing coherent intermolecular dipole–dipole coupling in real space
Luminescence induced by highly localized excitations that are produced by electrons tunnelling from the tip of a scanning tunnelling microscope is used to map the spatial distribution of the excitonic coupling in well-defined arrangements of a few zinc-phthalocyanine molecules and the dependence of this spatial distribution on the relative orientation and phase of the transition dipoles of the individual molecules.
Yang Zhang, Yang Luo, Yao Zhang et al. | Komatiites reveal a hydrous Archaean deep-mantle reservoir
Archaean komatiites are shown to originate in hot mantle plumes that entrained hydrous material from deep in the mantle.
Alexander V. Sobolev, Evgeny V. Asafov, Andrey A. Gurenko et al. | Boreal and temperate trees show strong acclimation of respiration to warming
Acclimation of leaf respiration to a 3–5-year period of warming by 3.4 °C for 10 North American tree species in forest conditions eliminated 80% of the increase in leaf respiration expected of non-acclimated trees; this suggests that the increase in respiration rates of terrestrial plants from climate warming, and the associated increase in atmospheric CO2 levels, may be less than anticipated.
Peter B. Reich, Kerrie M. Sendall, Artur Stefanski et al. | The mid-developmental transition and the evolution of animal body plans
Embryos in a particular phylum of the animal kingdom tend to most resemble one another at a stage in the middle of embryogenesis known as the phylotypic period; a transcriptional analysis of embryogenesis from single embryos of ten different phyla reveals that the transcripts expressed at the phylotypic stage (or mid-developmental transition) differ greatly between phyla, and a ‘phylum’ may be defined as a set of species sharing the same signals and transcription factor networks during the mid-developmental transition.
Michal Levin, Leon Anavy, Alison G. Cole et al. | Potentiating the antitumour response of CD8+ T cells by modulating cholesterol metabolism
Modulating cholesterol metabolism can improve CD8+ T-cell-mediated immunity against tumours; genetic or pharmacological inhibition of the cholesterol esterification enzyme ACAT1 led to higher plasma membrane cholesterol levels, better T-cell receptor clustering and signalling, improved immunological synapse maturation, and enhanced antitumour activity in mice.
Wei Yang, Yibing Bai, Ying Xiong et al. | β-Arrestin biosensors reveal a rapid, receptor-dependent activation/deactivation cycle
A series of FRET-based β-arrestin2 biosensors are used to study the dynamics and conformational changes that occur when β-arrestin2 binds to and dissociates from the β2-adrenergic receptor in living cells; results show that after β-arrestin2 dissociates from the β2-adrenergic receptor, it stays at the cell membrane in an active conformation for a while, indicating that β-arrestin is able to signal in a G-protein-coupled receptor (GPCR)-free state.
Susanne Nuber, Ulrike Zabel, Kristina Lorenz et al. | | | | |
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