Volume 466 Issue 7305, 22 July 2010

The controversy surrounding diabetes drugs highlights the importance of comparative studies.

Researchers and activists alike benefit from dialogue — and a clear line between legal and illegal acts.

The week in science.

As FDA advisers vote for restrictions on Avandia, researchers reveal a way to make such drugs safer.

Royal Society predicts 'game over' for British science.

Congressional watchdog unearths shortcomings at agency in charge of repatriating ancient tribal remains.

Studies highlight uncertainties over effects of climate change.

Targeted researchers support the legislation, despite free-speech concerns.

Degree-by-degree breakdown of climate effects published.

The Large Hadron Collider could throw up evidence of new physics earlier than expected.

NASA and Germany have spent 15 years and billions of dollars on SOFIA, an airborne telescope that is about to produce its first results. Eric Hand asks whether the science will justify the cost.

Eradicating any organism would have serious consequences for ecosystems — wouldn't it? Not when it comes to mosquitoes, finds Janet Fang.

A change in institutional culture is needed to promote responsible scientific behaviour and prevent misconduct. That's unlikely to happen unless money is involved, say Sandra Titus and Xavier Bosch.

A new survey shows that informal intervention can often avert much irresponsible scientific behaviour, and is not as risky as people might fear, say Gerald Koocher and Patricia Keith-Spiegel.

Brian Wynne wishes that a book on the vulnerability of scientific evidence to attack by ideologists had grappled more with the larger question of why science is such an easy target.

Antidiabetic drugs that activate the protein PPARγ had a bright start but soon lost their appeal because of undesirable side effects. Subtle modifications may once again make them suitable for treating diabetes.

An innovative way of mapping the large-scale structure in the Universe sidesteps the need to observe millions of galaxies individually. The approach holds promise for both astrophysical and cosmological studies.

Demonstrations of coupled phenotypic and demographic responses to climate change are rare. But they are much needed in formulating predictions of the effects of climate change on natural populations.

By putting the pieces of a chemical puzzle into the right order, a thorny problem in catalysis has been solved. This opens the door to syntheses of molecules that contain the useful trifluoromethyl group.

The organization of behaviour as sequences of actions requires proper initiation and termination of each action sequence. The neural circuit that signals instructions to start and stop is now revealed.

PPARγ ligands are used to control diabetes, but their anti-diabetic actions are puzzling. Here the authors show that phosphorylation of PPARγ by cyclin-dependent kinase 5 (Cdk5) in mice is linked to obesity induced by high-fat feeding, and that inhibition of the effect in humans by the drug rosiglitazone is closely associated with its anti-diabetic effects. Several anti-diabetic PPARγ ligands directly inhibit the effect, and thus support a more normal non-diabetic pattern of gene expression.

The appropriate initiation and termination of behavioural action sequences is imperative, but the neural mechanisms underlying the learning and execution of fixed behavioural patterns are poorly understood. Here the authors reveal start/stop neuronal activity in basal ganglia circuits that emerge during task training in mice. Genetically altering these circuits disrupted the activity and impaired performance, providing evidence for a causal relationship between the specific neuronal activity and task learning.

Hitherto, 21-cm emission has been detected in galaxies only to redshift 0.24, although it is possible to measure the aggregate emission from many more distant, unresolved sources in the 'cosmic web'. Here the authors report a three-dimensional 21-cm intensity field at redshift 0.53–1.12. They co-add neutral-hydrogen emission from the volumes surrounding about 10,000 galaxies to detect the aggregate 21-cm glow at a significance of approximately four standard deviations.

These authors report the concentrations of hydrogen, chlorine and sulphur in the mineral apatite from a lunar basalt, and show that the concentrations are indistinguishable from apatites in common terrestrial igneous rocks. They conclude that both metamorphic and igneous models of apatite formation suggest a volatile inventory for at least some lunar materials that is similar to comparable materials within the Earth.

Graphene nanoribbons (GNRs) have structure-dependent electronic properties that make them attractive for the fabrication of nanoscale electronic devices, but exploiting this potential has been hindered by the lack of precise production methods. Here the authors demonstrate how to reliably produce different GNRs, using precursor monomers that encode the structure of the targeted nanoribbon and are converted into GNRs by means of surface-assisted coupling.

The spontaneous assembly of two different types of nanoparticle into ordered superlattices offers a route to designing materials with precisely controlled properties, but available synthesis strategies have many practical limitations. These authors report a fabrication process which overcomes these limitations. They generate large-scale (square-millimetre) binary superlattice structures at a liquid–air interface, allowing the material to be free standing or transferred to any substrate ready for fabrication into useful devices.

The annual burial of organic carbon in lakes and reservoirs exceeds that of ocean sediments, but inland waters are components of the global carbon cycle that receive only limited attention. Here the authors find that the mineralization of organic carbon in lake sediments exhibits a strong positive relationship with temperature, suggesting that warmer water temperatures lead to more mineralization and less organic carbon burial.

Climate change can affect the phenology, population dynamics and morphology of species, but it is difficult to study all these factors and their interactions at once. Using long-term data for individual yellow-bellied marmots, these authors show that climate change has increased the length of the marmot growing season, leading to a gradual increase in individual size. It has simultaneously increased the fitness of large individuals, leading to a rapid increase in population size.

The European corn borer consists of two sex pheromone races, leading to strong reproductive isolation which could represent a first step in speciation. Female sex pheromone production and male behavioural response are under the control of different genes, but the identity of these genes is unknown. These authors show that allelic variation in a gene essential for pheromone biosynthesis accounts for the phenotypic variation in female pheromone production, leading to race-specific signals.

Transcriptional enhancers are segments of regulatory DNA located some distance from the coding region of a gene, and several of them may sometimes serve apparently redundant functions. These authors demonstrate in Drosophila that such 'redundant' enhancers, by contributing higher overall levels of transcription, ensure robustness of phenotypes against both genetic and environmental perturbations, for example mutations in other genes or temperature changes that would otherwise lead to aberrant development.

Plants or animals with identical genomes in a given species can develop into wildly differing forms, depending on environmental conditions, a phenomenon that is widespread in nature yet rarely described in genetic and molecular terms. These authors show that the formation of additional teeth-like structures in the mouth of the nematode Pristionchus pacificus in response to overcrowding is mediated by the same endocrine system that controls dauer larva formation.

The insulin/IGF-1 signalling (IIS) pathway is involved in various biological processes, including regulation of longevity. In the worm Caenorhabditis elegans, the transcription factor DAF-16a, one of two isoforms, has a major role in this pathway, regulating longevity, stress response and dauer diapause. These authors describe a new isoform, DAF-16d/f, which is also important in the regulation of lifespan. The DAF-16 isoforms functionally cooperate to fine-tune IIS-mediated processes in the context of a whole organism.

PHF8 is a JmjC domain-containing protein, the gene for which has been linked to X-linked mental retardation (XLMR). These authors demonstrate PHF8 to be a histone demethylase with activity against H4K20me1. It has a role in regulating gene expression as well as in neuronal cell survival and craniofacial development in zebrafish. The results suggest there may be a link between histone methylation dynamics and XLMR.

These authors show that the JmjC domain-containing protein PHF8 has histone demethylase activity against H4K20me1 and is linked to two distinct events during cell cycle progression. PHF8 is recruited to the promoters of genes involved in the G1–S phase transition, where it removes H4K20me1 and contributes to gene activation, whereas dissociation of PHF8 from chromatin in prophase allows H4K20me1 to accumulate during mitosis.

Here the authors show that in non-excitable LNCaP prostate cancer cells, the large-conductance, voltage- and calcium-activated potassium (BK) channel can be activated at negative voltages without rises in intracellular Ca²⁺ concentration, by interacting with an auxiliary protein, the leucine-rich repeat containing protein 26. This auxiliary protein modulates BK channel gating by enhancing the allosteric coupling between voltage-sensor activation and the channel's closed–open transition.

Life sciences play a major role in Shanghai’s growing business community.

Kewen Jin, general manager of Charles River Laboratories China, a contract research organization for preclinical services, discusses the opportunities and challenges for Shanghai.

Federal agreement aims to cut through red tape.

'Alternative' careers may be commonplace, but that doesn't mitigate a sense of failure, says Katherine Sixt.

A delicate balancing act.