Research articles

Parasites of the Theileria genus infect cattle and transform their host cells, a transformation that can be reversed by treatment with the drug buparvaquone; here, a Theileria homologue of the peptidyl-prolyl isomerase PIN1 is shown to be secreted into the host cell, where it promotes transformation and can be directly inhibited by buparvaquone.

The monocyclic β-lactam rings of the nocardicin family of antibiotics are biosynthesized by an unprecedented activity of non-ribosomal peptide synthetases, a mechanism that is distinct from the pathways to the other classes of β-lactam antibiotics.

A sub-ångström-resolution X-ray crystal structure of [NiFe] hydrogenase, with direct detection of the products of the heterolytic splitting of dihydrogen into a hydride bridging the Ni and Fe and a proton attached to the sulphur of a cysteine ligand.

Two genetically distinct populations of neurons in the subfornical organ of mice can either induce thirst and water-seeking behaviour or suppress thirst, regardless of the hydration status of the animal.

Observations of rapid, persistent elevation gains that occur on the ice surface above a subglacial lake as the lake is refilled with surface meltwater during the summer melt period in Greenland show that surface meltwater may be trapped and stored at the bed of an ice sheet, affecting ice dynamics downstream.

Genome-wide association studies are used to identify common genetic variants that affect the structure of selected subcortical regions of the human brain; their identification provides insight into the causes of variability in brain development and may help to determine mechanisms of neuropsychiatric dysfunction.

Apoptotic cell death is required for morphogenesis of the developing leg joint of fruitflies; using this model system, the authors show here that within apoptotic cells a transient pulling force exerted through a highly dynamic apico-basal myosin II cable-like structure acts as a mechanical signal to increase tissue tension and modify tissue shape.

Time-resolved resonance Raman vibrational spectroscopy was used to study the mechanism of soluble methane monooxygenase and obtain structural information on the key reaction cycle intermediate, compound Q, which contains a unique dinuclear Fe^IV cluster that breaks the strong C-H bond of methane and inserts an oxygen atom (from O₂) to form methanol.

Construction of a series of genomically recoded organisms whose growth is restricted by the expression of essential genes dependent on exogenously supplied synthetic amino acids introduces novel orthogonal barriers between these engineered organisms and the environment, thereby creating safer genetically modified organisms.

Genome-wide localization and activity analysis of the de novo DNA methyltransferases DNMT3A and DNMT3B in mouse embryonic stem cells identifies overlapping and individual targeting preferences to the genome, including a role for DNMT3B in gene body methylation.

Initially weak episodic memories in humans can be selectively enhanced and consolidated following later emotional learning involving conceptually related information, suggesting a mechanism for how we can remember initially inconsequential information after a relevant later experience.

Nanomagnetic imaging has been used to obtain a palaeomagnetic time series of two pallasite meteorites, revealing that their convection was driven by core solidification, which would have caused long-lived magnetic fields in the cores of early Solar System planetary bodies.

Dissociating early from late fear memory retrieval in rats reveals that while the projection from the prelimbic prefrontal cortex to the amygdala is critical for fear memory retrieval at early time points, a separate circuit involving the paraventricular region of the dorsal midline thalamus is critical for fear memory retrieval at late time points, establishing the paraventricular region as a critical maintenance/retrieval node during the transition from short- to long-term fear memory.

Development of a segmented filamentous bacteria and host cell co-culturing system that supports filamentation, segmentation, and differentiation to release viable infectious intracellular offspring.

A method to measure the precise relationship between neuronal firing rates and the representation of accumulated evidence is described; results in the parietal and prefrontal cortex of rats, together with transient optogenetic inactivation of the prefrontal cortex, challenge the prevailing view that the prefrontal cortex is part of the neural circuit for accumulating evidence, and suggest that neurons in parietal and prefrontal areas have distinct relationships to evidence accumulation in decision-making.

Inhibiting projections from the paraventricular nucleus of the thalamus to a specific division of the amygdala prevents fear conditioning in mice, indicating an important role for the thalamus–amygdala circuit in establishing and maintaining fear responses.

α-MSH and AgRP, two hypothalamus-derived peptides with opposing actions on the melanocortin-4 receptor (MC4R), modulate neurons driving feeding behaviour; although previous downstream mechanisms of cellular modulation by these peptides have been determined, here α-MSH and AgRP are shown to regulate neural activity by coupling MC4R to Kir7.1 potassium channels and closing or opening them, respectively.

Attosecond light pulses are now available experimentally, enabling ultrafast processes on the atomic scale to be probed; here the free-electron-like propagation of electrons through ultrathin layers of magnesium is observed in real time.

A copper-catalysed dynamic kinetic asymmetric transformation using racemic substrates and alkyl nucleophiles is reported; organometallic reagents are generated in situ from alkenes by hydrometallation, and give highly enantioenriched products under mild reaction conditions.

Chemical force microscopy measurements show that the immobilization of specific cationic groups near non-polar domains produces pronounced changes in the domains’ hydrophobic interaction strengths: charged ammonium groups double interaction strengths, whereas guanidinium groups eliminate measurable interactions.