Research articles

The formation of magnetic vortices such as skyrmions is hampered by the stochastic nature of thermal fluctuations. Here, the authors demonstrate that ultrafast dynamics in the initial stages of vortex formation can dominate the stochastic behaviour observed in the steady state.

Photonic topological insulators have been theoretically predicted but their experimental demonstration has proven challenging. Here, Chen et al.experimentally realize a photonic topological insulator by embedding a non-bianisotropic and a non-resonant metacrystal into a waveguide.

The relationship between mutations and phenotypic changes associated with drug resistance in bacteria remains unclear. Here, the authors use antibiotic-resistant E. colistrains, obtained by laboratory evolution, to show that resistance profiles can be predicted by changes in expression of a few genes.

Ramachandran plots are a convenient means of describing protein backbone conformation by depicting the distribution of Ca bond rotations. Here, the authors devise an alternative descriptor based on hydrogen bond rotations, and apply it to describe protein structures using a vocabulary of 30 hydrogen-bonding motifs.

MEN1 gene encodes menin, a nuclear scaffold protein that regulates transcription and is often inactivated in pancreatic neuroendocrine tumours (PNETs). Here Jiang et al. show that MEN1-driven PNET development involves activation of β-catenin, and that β-catenin deletion ameliorates the disease.

The contribution of signal strength on cell fate decisions is often not reflected in signalling networks. By combining mathematical simulation and biochemical experiments in cultured adult cardiomyocytes, Shin et al. show that the concentration of a β-adrenergic receptor agonist affects the expression of Bcl-2, influencing the balance between cell survival and death.

A polymer stereocomplex can possess quite different properties to its constituent homopolymers. Here, the authors prepare stereocomplex micelles of amphiphilic block-copolymers via crystallization-driven self-assembly, and observe a change from cylindrical to mixed spherical micelle morphology.

Ferrets constitute a useful model for influenza research because they are susceptible to human-adapted flu viruses. Here, the authors show that ferrets, like humans, lack a functional CMAH enzyme and synthesize a single type of sialic acid (Neu5Ac), resulting in naturally humanized influenza virus receptors.

The preservation of soft tissues during fossilization is the outcome of a race between decay and mineralization. Here the authors show that differential preservation of the Gaojiashan fossil Conotubus hemiannulatuswas influenced by the duration of tissue degradation through bacterial sulfate reduction.

Chemical inhibitors of the tumour-progression promoting arachidonic acid metabolism pathway prolong post-treatment survival of cancer patients. Here the authors analyse sequence variation in oral cancer patients and show that loss-of-function mutations in this pathway prolong survival.

Misrepair of DNA double-strand breaks can lead to chromosomal rearrangements, which can promote carcinogenesis. Here, the authors show in cultured human astrocytes that transcriptional activation impacts on DNA double-strand break formation and repair upon ionizing radiation in a site-specific manner.

The correct assembly of genomes from sequencing data remains a challenge due to difficulties in correctly assigning the location of repeated DNA elements. Here the authors describe GRAAL, an algorithm that utilizes genome-wide chromosome contact data within a probabilistic framework to produce accurate genome assemblies.

B cells rearrange the immunoglobulin heavy chain genes to produce a functional B cell receptor, but how it is decided that one allele rearranges first is not clear. Here the authors provide evidence that in the majority of common lymphoid precursor clones, the two alleles have a similar probability of rearranging first.

Pentatricopeptide repeat (PPR) proteins bind RNA and control diverse aspects of RNA metabolism in eukaryotic cells. Here, Coquille et al.present the crystal structures of several engineered PPR domains, elucidate their RNA binding mode and suggest paths to the design of modular, sequence-specific PPR domains.

Hypochlorous acid generated by neutrophils acts as a potent antibacterial agent. Müller et al. now show that this oxidant directly activates a protective counter-response in E. coli by N-chlorinating the protein RidA and converting it into an effective protein chaperone.

The Orai1 Ca²⁺ channel is activated by STIM1 in response to Ca²⁺ release from the ER. Here Maléth et al.show that Orai1 inactivation occurs by translocation to PI(4,5)P2-rich plasma membrane microdomains, which facilitates recruitment of SARAF, a negative regulator of STIM1 function.

In the adult brain, the neurotrophic factor basic fibroblast growth factor (bFGF) is predominantly secreted by astrocytes. Here the authors use optogenetics to activate astrocytes, leading to release of bFGF, inducing enhanced dopaminergic differentiation of neural progenitors and promoting brain repair in a mouse Parkinson’s disease model.

Synaptic vesicle fusion involves a multi-protein assembly called the SNARE complex that is tightly regulated both spatially and temporally. Here Kavanagh et al. show that after vesicle fusion and SNARE complex disassembly in the synapse, the SNARE protein syntaxin1a is sequestered in a monomeric form by munc18-1, preventing ectopic SNARE complex assembly.

Temperature jump technique is widely used to probe the fast dynamics of protein and DNA folding, but constrained to modest temperature control. Here, the authors use a microfluidic device combined with an infrared laser to heat or cool DNA hairpins up to 70 °C on a microsecond time scale.

The regulated passage of ions through a porous membrane is a process applicable to various research disciplines. Here, the authors present a method for the control of porous membrane ion transport, using a deposited layer of ligand-functionalized nanoparticles.