Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain
the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in
Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles
and JavaScript.
Malnutrition affects many millions of people in the developing world and remains a problem in wealthy nations, especially for disadvantaged groups. In many cases, it is the associated diarrhoea and intestinal inflammation that cause morbidity and death. A study published in this issue presents a molecular explanation for the increased susceptibility to intestinal inflammation in malnutrition. Angiotensin converting enzyme 2, which has a central role in blood-pressure regulation and has been implicated in diabetes, heart failure and viral infection, is shown to influence dietary amino-acid homeostasis, innate immunity, gut microbial ecology and susceptibility to colitis. Mice deficient in this enzyme show impaired tryptophan metabolism and develop colitis, which is alleviated by dietary tryptophan and its metabolite, nicotinamide. This surprising result explains nutritional effects that have been known for centuries and provides a molecular link between malnutrition and the intestinal microbiome. Cover: 22 March 1993, a victim of famine in Ayod, South Sudan (Jon Jones/Sygma/Corbis).
Staff-surveillance efforts by government agencies must not contravene the rights of whistle-blowers, as the US Food and Drug Administration is accused of doing.
The three planets of the Kepler-30 system align closely with a starspot, indicating their common birth in a gaseous disk. Similar alignments could inform us about the origin of planets orbiting our stellar neighbours. See Letter p.449
The myelin sheath around nerve fibres serves to speed up electrical nerve signals. But it turns out that it also supplies neurons with fuel to support their high metabolic activity. See Article p.443
The discovery of a powerful way to switch a material from an insulator to a metal might ultimately be exploited to build a new generation of electronic switches. See Letter p.459
Dietary lack of a single amino acid impairs intestinal immunity in mice, altering the guts microbial community and leaving it vulnerable to damage. The finding helps to explain how malnutrition favours gut inflammation. See Letter p.477
Antiretroviral therapies block HIV replication but they do not eliminate inactive viruses within cells. A clinical trial shows that a drug can revive HIV in patients as a potential first step towards a cure. See Letter p.482
A method has been developed for preparing a variety of potentially useful spherical particles, ranging from several nanometres to millimetres in diameter. It relies on the same fluid instability that causes taps to drip. See Letter p.463
Producing a single image from two eyes requires complex brain circuitry. A comparison of neural responses in babies shows that early visual stimulation following premature birth leads to accelerated development of the visual system.
Disruption of the lactate transporter monocarboxylate transporter 1 (MCT1), which is highly enriched within oligodendroglia and reduced in patients with amyotrophic lateral sclerosis (ALS), causes axon damage and neurodegeneration in animal and cell culture models, suggesting a fundamental role for MCT1 in metabolic support of axons and ALS pathogenesis.
An analysis of transits of planets over starspots on the Sun-like star Kepler-30 shows that the orbits of the three planets are aligned with the stellar equator; this configuration is similar to that of our Solar System, and suggests that high obliquities are confined to systems that experienced disruptive dynamical interactions.
A ‘Higgs’ mode, signifying the breaking of a continuous symmetry in a model with emergent Lorentz invariance, is found close to the transition to the Mott insulating phase in a two-dimensional neutral superfluid.
A conceptually new type of transistor, based on a strongly correlated material, allows external control of a macroscopic electronic phase transition, and gives rise to a non-volatile memory effect.
Uniformly sized, structured spherical particles can be made in large quantities and across a wide range of sizes by an ingenious technique involving heating and drawing out multi-component fibres.
Estimates of ice loss from the West Antarctic Ice Sheet depend on accurate modelling of dynamic thinning, for which knowledge of basal topography is needed; here, ice-penetrating radar, gravity and magnetic measurements reveal a subglacial rift basin that acts as a conduit between the Bellingshausen Sea and the ice-sheet interior.
The sensitivity of ecosystem respiration to seasonal changes in temperature is shown to be remarkably similar for a wide range of ecosystem types spanning the globe; however, terrestrial and aquatic ecosystems differ markedly in their temperature sensitivity over annual timescales.
Mutations in angiotensin-converting enzyme 2 are shown to predispose mice to colitis as a consequence of neutral amino acid malabsorption and a change in the resident microbiota; these results could explain how protein malnutrition — affecting up to one billion people — leads to intestinal inflammation.
The latent HIV-1 reservoir represents a major barrier to curing patients with HIV-1 infection, and now in vivo evidence is presented that vorinostat can disrupt proviral latency of HIV-1.
A systems approach provides a global perspective of the different strategies that viruses use to modulate the cellular innate immune response; this may be useful in the design of future viral intervention strategies.
Combining analysis of host proteome and transcriptome perturbations induced by tumour virus proteins with ongoing genome-wide studies of cancer facilitates the prioritization of cancer genes.
A non-invasive method is used to study and manipulate hair-follicle regeneration over time in live mice, and shows that hair growth involves spatially regulated cell divisions, cellular reorganization and migration of epithelial cells, and that the mesenchyme is required for hair growth.
The secretion of hepatocyte growth factor by stromal cells in the tumour micro-environment can make melanoma resistant to RAF inhibitors, through the activation of the MET signalling pathway, but a combination of RAF and MET inhibitors can overcome this resistance.
The efficacy of kinase inhibitors in treating cancer is limited by drug resistance; here it is shown that most human tumour cells can develop drug resistance through being exposed to one or more receptor tyrosine kinase ligands.
A new method allows the collection of circulating tumour cells (CTCs) despite their rarity; transcriptome sequencing of CTCs could allow identification of pathways involved in metastasis.
The caa3-type cytochrome oxidase structure described here provides insight into the coupling of energy transduction to the complete reduction of oxygen.
The second phase of the German Excellence Initiative is helping scientists and universities. But sustaining its gains in the long term could be a challenge.