Articles

Heat shock proteins bind to CD91 on antigen presenting cells, resulting in the presentation of chaperoned peptides to T cells. Here, heat shock protein binding is shown to induce phosphorylation of CD91 and stimulate the production of cytokines, thus priming various T-helper cell responses.

Erythropoietin circulates in the blood and is essential for erythropoiesis but its role in metabolic homeostasis has not been examined. Tenget al. show that when the erythropoietin receptor is only expressed in erthyroid cells, mice develop obesity and insulin resistance, suggesting that the receptor has a key role in fat mass accumulation.

APOBEC3 is a DNA editing enzyme that is important for antiviral responses. In this study, Carmi and colleagues show that APOBEC3 editing of retrotransposon sequences in mammalian genomes is widespread, with implications for the evolution of retrotransposons.

Magnetostriction—the property that causes ferromagnetic materials to change shape during the process of magnetization—has a range of technological applications. Here, by varying the presence of structural disorder in textured Co_1-xFe_xfilms, unusually strong magnetostrictive properties are presented.

Stomagen is a positive regulator of stomatal development in plants, whereas epidermal patterning factors 1 and 2 are negative regulators. Ohkiet al. present the NMR structure of stomagen and show that the stomagen loop domain is sufficient to positively regulate stomatal development.

Stimulus-responsive hydrogels have previously been developed that display heat-, light-, pH- or redox-induced sol–gel transitions. Nakahataet al. develop a self-healing supramolecular hydrogel based on host–guest polymers in which redox potential can induce a reversible sol–gel phase transition.

Large scale synapse assays can facilitate identification of drug leads. Shiet al. develop a 'synapse microarray' technology that enables sensitive, high-throughput, quantitative screening of synaptogenic events, and use it to identify novel histone deacetylase inhibitors that enhance synaptogenesis.

In multi-component mixtures of self-assembling molecules, small differences in association energy between components can be amplified by nonlinear effects. This theoretical investigation of self-assembling systems rationalizes chiral amplification in cooperative supramolecular copolymerizations.

MicroRNAs bind to the 3′-untranslated region of genes to regulate expression. In this study, an RNA-binding protein, RMB38, is shown to selectively regulate the access of some microRNAs to their targets, and control the expression of some p53 target genes.

Intercalating alkali metals into picene—a hydrocarbon with five linearly fused benzene rings—results in superconducting materials. Now, alkali-metal-doped phenanthrene, which consists of three fused benzene rings, is also found to be superconducting, opening up a broader class of organic superconductors.

Biological digital sensors require the fabrication of modular genetic logic gates. Using thePseudomonas syringae hrpsystem, Wang and colleagues generate AND, NOT and NAND gates, demonstrating the ability to engineer a modular system from biological elements.

In the theory of general relativity time flows at different rates depending on the space–time geometry. Here, a drop in the visibility of a quantum 'clock' interference in a gravitational potential is predicted, which cannot be explained without the general relativistic notion of time.

During cell division, a cytoplasmic bridge—the midbody—forms between the nascent daughter cells, but it has been unclear under which conditions this is retained by a daughter cell or released. Now, Ettinger and colleagues show that midbody-release occurs more frequently in stem cells compared with cancer cells.

Memory retrieval followed by extinction training has been shown to erase fear memories. Flavellet al. show that this approach also erases appetitive memories in rats and results from a modification of memory reconsolidation, which could be useful for the treatment of drug addiction.

Nanofluidic diodes are utilized for the rectification of ionic transport, but their rectifying properties cannot be altered after the devices are made. Here, a field-effect reconfigurable nanofluidic diode is reported in which the forward direction and the degree of rectification can be modulated by a gate voltage.

The interfaces between complex oxides can play host to a range of interesting electronic phenomena. Xieet al. demonstrate that the electronic properties at the LaAlO₃/SrTiO₃interface can be tuned upon application of common polar solvents such as acetone, ethanol and water.

Hoop-shaped aromatic hydrocarbons can be considered as finite models of single-wall carbon nanotubes. Hitosugiet al. describe the bottom-up synthesis of a macrocyclic tetramer of chrysene, and show that its persistent rotational isomers are finite models of chiral nanotubes.

The Early Palaeoproterozoic saw glaciations and a rise in atmospheric oxygen, but the link between these two changes is poorly understood. Here, osmium isotope records from sedimentary rocks indicate synchronicity between an episode of increasing oxygen and a glacial transition.

Molecular probes that can detect aqueous sulphides could help to elucidate their roles in biological signalling. Qianet al. develop two sulphide-selective fluorescent probes and demonstrate their ability to image free sulphide in living cells.

In non-NMDA glutamate receptors, intersubunit contacts within agonist binding domains affect functional desensitization. Now, NMDA receptor activation, but not desensitization, is shown to involve rearrangements at the heterodimer interface, suggesting that the intersubunit contacts of NMDA and non-NMDA receptors may have distinct functional roles.