Research articles

B-RAF is mutated in a large proportion of melanomas, and the first small molecule inhibitor has recently been approved for melanoma treatment. Here, by exome sequencing melanoma samples, Shi and colleagues show that B-RAF is amplified in tumours that have acquired resistance to the B-RAF inhibitor vemurafenib.

Diffractive imaging can deliver wavelength-scale resolution with X-rays, although its use with electrons is hampered by experimental constraints. By applying ptychographic methods to transmission electron microscopy, Humphryet al. demonstrate sub-nanometre resolution using low-energy electrons.

Human immunodeficiency virus patients who maintain low levels of virus or have undetectable levels of virus exist. In this study, the HIV found in two of these patients is shown to replicatein vitro, suggesting that host factors have a role in suppressing virus levels.

Megakaryocytes undergo polyploidization prior to forming platelets but this process is poorly characterised. In this study, non-muscle myosin IIB heavy chain, that localizes to the contractile ring during mitosis, is shown to be silenced prior to polyploidization in a RUNX1-dependent manner.

Biological materials efficiently exploit self-assembly of simple constituents to produce complex functional structures such as optical devices. By controlling organic molecules, Leeet al. show fast two-step self-assembly of CaCO₃microlens arrays, reminiscent of their biological counterparts.

Glutathione's key role as a modulator of reactive oxygen species levels has recently been challenged. Quintana-Cabreraet al. now provide in vivoevidence supporting an antioxidant and neuroprotective function for γ-glutamylcysteine, which replaces glutathione by acting as glutathione peroxidase-1 cofactor.

The expression of the tumour suppressor p16 is frequently lost in cancer. Zhanget al. show in cultured cells that p16 mRNA levels are stabilised by methylation of the 3′-untranslated region by the tRNA methyltransferase NSun2, revealing a new mechanism for regulating p16.

Barley is an important food crop that has been adapted to grow on acidic soils that often contain toxic soluble aluminium. In this study, an insertion in the upstream region of a citrate transporter is shown to confer resistance of barley to aluminium toxicity and is found in aluminium-tolerant barley accessions.

Some animal populations are able to shift their birth sex ratio from the expected unity. This study shows, using fluorescencein situhybridization, that in a captive population of pygmy hippopotamus the males appear to be able to adjust the ratio of X- and Y-chromosome-bearing spermatozoa in their ejaculates.

Lateralization of the brain can provide evolutionary advantages by enhancing behavioural and cognitive capacities. Manns and Römling confirm that lateralized environmental experience in pigeons induces hemispheric specialization and show that this affects the efficiency of interhemispheric crosstalk.

Imaging and tracking the motion of single molecules on cell plasma membranes requires high spatial resolution in three dimensions. Honget al. develop a plasmonic ruler based on the fluorescence enhancement of carbon nanotubes on a gold plasmonic substrate, allowing the observation of nanotube endocytosis in three dimensions.

The Tyrolean Iceman is 5,300 years old and his mitochondrial genome has been previously sequenced. This study reports the full genome sequence of the Iceman and reveals that he probably had brown eyes, was at risk for coronary disease and may have been infected with the pathogen Lyme borreliosis.

Humans are a network of complex physiological systems, but quantifying these diverse systems is a challenge. This study presents a method to show that each physiological state is characterized by a specific network structure, demonstrating a connection between network topology and function.

Multicompartment micelles can be assembled from block copolymers but it is difficult to manipulate their hierarchical superstructures using straightforward concepts. Here, methods are developed that involve the pre-assembly of subunits for the structurally controlled production of micelles.

Understanding defects in liquid crystals is important for controlling their structure and self-assembly properties. Here, nematic liquid crystals confined in microwrinkle grooves show new periodic arrangements and zigzag line defects that can trap particles, offering a method for colloid manipulation.

A detailed assessment of near-shore temperature changes is needed for improved forecasts of the consequences of coastal warming. Here, changes in coastal sea surface temperature are estimated, showing that although 71% of the world's coastlines are warming, the rates of change have varied spatially.

The exact speed of spoken word processing by our brain is still unknown. Using MEG to compare brain responses to words and pseudowords, MacGregoret al. show that lexical processing occurs 50 ms after acoustic information is presented, suggesting that our brain's access to word information is near-instantaneous.

Perturbation of the cardiac voltage-gated sodium channel, Na_V1.5, by drugs or inherited mutation can underlie and trigger cardiac arrhythmias. Here, the role of the Na_V1.5 carboxy terminus in channel inactivation is investigated, and structural details of an arrhythmia associated H6 mutant are reported.

Interpolar microtubules were thought to be indispensable for eukaryotic cell division. Here, Akera and colleagues demonstrate that the second division of meiosis in yeast can occur in the absence of interpolar microtubules, and identify the forespore membrane as a force producing structure in cell division.

Grain boundaries in graphene degrade its properties, and large single-crystal graphene is desirable for electronic applications of graphene. Gaoet al. develop a method to produce millimetre-sized hexagonal single-crystal graphene grains, and films composed of the grains, on platinum by chemical vapour deposition.