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The focal adhesion kinase has a role in cell adhesion and migration. In this study, a fluorescent resonance energy transfer biosensor is designed to monitor focal adhesion kinase activity at membrane microdomains, revealing that the mechanisms that activate focal adhesion kinase are stimulus dependent.

Single-molecule magnets could be useful for the development of spintronic devices. Here single-molecule magnets are encapsulated in carbon nanotubes without affecting the properties of the guest molecules, which may be useful in the development of spintronic or high-density magnetic storage devices.

Pagerank is widely used to rank web content; however, it is unknown how network topology affects its performance. The authors demonstrate that, in random networks, pagerank is sensitive to perturbations in topology, whereas scale-free networks contain a few super-stable nodes whose ranking is exceptionally stable.

Materials that can separate and capture carbon dioxide from power plant flue gases could help to stabilize atmospheric levels of the gas. Mohantyet al. develop inexpensive porous organonitridic frameworks with high selectivity and sorption capacities for carbon dioxide and methane.

In some iron-based materials, unconventional superconductivity can emerge near a quantum phase transition where long-range magnetic order vanishes. Giovannettiet al.show that the magnetic quantum phase transition in an iron pnictide superconductor is very close to the quantum tricritical point.

The pore gating mechanism of the proton-activated sodium channel ASIC1 is poorly understood. Canessaet al.study the shape of the ion pathway in the ASIC1 channel in its open and closed states, and reveal the opening, closing and desensitization mechanisms of the channel.

Why some species have evolved to produce sterile individuals working for the benefit of others has yet to be fully explained. Now, a mathematical model of the dynamics of insect colony foundation, growth and death shows that monogamy and haplodiploidy facilitate the evolution of this societal structure.

Posttranslational modification of proteins by small ubiquitin-related modifier is a response to stress signalling in plants. Here, theArabdiposisprotein SIZ1 is shown to cause SUMOylation of nitrate reductases 1 and 2 and to increase their activity, suggesting that SIZ1 controls nitrate uptake via SUMOylation.

Polo-like kinase 1 is a key regulator of mitosis and is a candidate for drug development to treat cancer. Here, reduced expression of polo-like kinase 1 in adult mice has a minor impact on animal physiology, suggesting that polo-like kinase 1 inhibitors may be useful in the killing of tumour cells while sparing normal cells.

Chk2 is a kinase that is a potential chemotherapeutic target. Here, Chk2 and the kinase ERK are shown to functionally interact, and are elevated in expression in human diffuse B-cell lymphomas. Combinatorial inhibition of the kinases was also shown to block tumour growth in anin vivomouse model.

Interacting electrons in one dimension are predicted to have independent spin and charge excitations. Wakehamet al. show evidence of this behaviour in a bulk conductor by measuring a ratio of thermal to electrical conductivity orders of magnitude larger than in conventional three-dimensional metals.

The fractional quantum Hall effect occurs when electrons move in Landau levels. In this study, using a theoretical flat-band lattice model, the fractional quantum Hall effect is observed in the presence of repulsive interactions when the band is one third full and in the absence of Landau levels.

Covalent reactions on carbon nanotube surfaces typically occur at random positions on the hexagonal lattice. Denget al. show that Billups–Birch reductive alkylation takes place at, and propagates from, sp³defect sites, leading to confinement of the reaction fronts in the tubular direction.

Optical computing, involving on-chip integrated logic units, could provide improved performance over semiconductor-based computing. Here, a binary NOR gate is developed from cascaded OR and NOT gates in four-terminal plasmonic nanowire networks; the work could lead to new optical computing technologies.

Iron pnictide compounds have recently been shown to have superconducting properties. Xuet al. show that the superconducting gap of underdoped pnictides scales linearly with the transition temperature, and that a pseudogap develops with underdoping.

Tissue regeneration is of great interest; however the number of times a given tissue can regenerate is unknown. Now, Eguchiet al. demonstrate that the lens of the Japanese newt—Cynops pyrrhogaster—can regenerate 18 times over a 16-year period, and that the new lenses are similar to those of control adult animals.

Thioredoxin reductase 1 is a flavoprotein that is involved in the regulation of redox homeostasis. Fritz-Wolfet al. report the first crystal structures of thioredoxin reductase 1 in complex with its substrate, thioredoxin, and confirm that the enzyme uses a flexible carboxy-terminal arm for electron transport to its substrates.

Group-1 influenza A neuramidase proteins have a 150-cavity that can be targeted by drugs, but the 2009 H1N1 virus neuramidase is not thought to have a 150-cavity. Here, biophysical simulations show that the 2009 H1N1 neuramidase exists in solution with an open 150-cavity, which is stabilized by a salt bridge.

During development, Wnt-mediated Notch signalling controls the generation of somites from the presomitic mesoderm, but the precise signalling mechanism is unknown. Here, the transcription factor Mesogenin 1 is shown to be a direct target of Wnt3a and regulates the transcription of a Notch signalling program.

The torsinA protein localizes to the endoplasmic reticulum and, when mutated, causes early onset torsion dystonia. The authors reveal a new role for torsinA in proteosome-mediated degradation of misfolded proteins, and relate this to endoplasmic reticulum stress, in aCaenorhabditis elegansmodel and patient fibroblasts.