Volume 470 Issue 7334, 17 February 2011

As Congress tries to tackle the $1.3-trillion US deficit by cutting the $660-billion discretionary budget, scientists must unite with non-traditional allies to ensure that research doesn't suffer.

To ensure their results are reproducible, analysts should show their workings.

In the wake of the revolution, Egypt should embrace a future based on scientific thinking.

A new water strategy from the Chinese government is a step in the right direction, says Chaoqing Yu. But it will be difficult to put into practice.

The week in science.

Increases for science and technology in the 2012 US budget prioritize innovation over reductions in the national deficit.

Likelihood of extreme rainfall may have been doubled by rising greenhouse-gas levels.

Scientists are frustrated by slow progress in the roll-out of funds to investigate the aftermath of Deepwater Horizon.

Animal model off-limits to Rett-syndrome researchers.

If a camera snaps everything you eat, you can't lie about it later. That's why scientists are building high-tech gadgets to measure the human 'exposome'.

The Templeton Foundation claims to be a friend of science. So why does it make so many researchers uneasy?

Will the $27-billion investment in electronic records in the United States revolutionize care and research, or will it be a missed opportunity for patients and science?

Sara de Freitas applauds a bold argument that online gaming can save the planet.

Two books debunk gender differences in the brain, discovers Virginia Valian.

A Chilean film juxtaposes astronomy with the search for those killed under Augusto Pinochet, finds Alison Abbott.

Anthony King explores a Dublin exhibition that exposes the controversies of synthetic biology.

Variation in a genomic region that contains the cancer-associated gene ATM affects a patient's response to the diabetes drug metformin. Two experts discuss the implications for understanding diabetes and the link to cancer.

Deposits in China dating to about 600 million years ago contain carbon compressions of algae and other organisms. The fossils provide a new window into the early evolution of complex multicellular life. See Letter p.390

During migration, cells interact with their environment by exerting mechanical forces on it. A combination of two techniques shows that they do so in all three dimensions by a push–pull mechanism.

Ageing is a complex process involving defects in various cellular components. The latest evidence suggests a unifying mechanism for cellular ageing that is relevant to the development of common age-related diseases. See Article p.359

Metamaterials are best known for their ability to bend light in the opposite direction to that of all materials found in nature. A hidden ability of these man-made materials has now been discovered. See Letter p.369

Rising concentrations of anthropogenic greenhouse gases in the atmosphere may already be influencing the intensity of rainfall and increasing the risk of substantial damage from the associated flooding. See Letters p.378 & p.382

This study focuses on developing mouse skin where mitotic basal progenitor cells switch from symmetric divisions to asymmetric division concomitant with stratification. Using a novel technical approach, the genetic pathway regulating spindle orientation is dissected, providing the first direct evidence that the proteins governing spindle orientation (LGN, NuMA and Dctn1) promote asymmetric cell divisions regulated by Notch signalling in mammalian cells in vivo.

Here it is shown that telomere dysfunction drives metabolic and mitochondrial compromise. Mice with dysfunctional telomeres activate p53, which in turn represses PGC-1α and PGC-1β, master regulators of metabolic and mitochondrial processes. This results in reduced mitochondrial mass, mitochondrial dysfunction and reduced ATP generation, impaired gluconeogenesis, cariomyopathy and increased reactive oxygen species. This telomere–p53–PGC pathway shows how telomere dysfunction may compromise organ function and contribute to age-related disorders.

The super-massive black holes of 10⁶ to 10⁹ solar masses that reside in the nuclei of active galaxies (AGN) are surrounded by a region emitting broad emission lines, probably associated with an accretion disk, which cannot be resolved spatially. The relative significance of inflow, outflow, rotational, or turbulent motions in the broad-line region as well as their structure (spherical and/or thin/thick accretion disk) are unknown. This study reports a fundamental relation between the observed emission line width and shape in AGN spectra, from which it is inferred that the geometry of the inner region is flattest for the fast-rotating broad-line objects whereas slow-rotating narrow-line AGN have a more spherical structure. Knowing the rotational velocities one can derive more accurately the central black hole masses, which are two to ten times smaller than previously estimated.

In the area of metamaterials it is shown that electromagnetic properties can be achieved that are not attainable with natural materials. The main research efforts have been directed towards experimentally realizing materials with negative refractive index, but to extend the potential and design flexibility for novel 'transformation optics' applications, it is of considerable interest to produce a material with unnaturally high refractive index. A broadband, flexible terahertz metamaterial with unprecedented high refractive index, reaching a value of 38.6, is now demonstrated.

This study demonstrates how it is possible to extract full three-dimensional structural information at atomic resolution using a combination of electron tomography and electron microscopy, coupled with separately available knowledge of the crystallographic structure adopted by the target nanoparticle. Such information should ultimately lead to a better understanding of the desirable properties of these systems.

A significant effect of anthropogenic activities has already been detected in observed trends in temperature and mean precipitation. But so far, no study has formally identified such a human fingerprint on extreme precipitation — an increase in which is one of the central theoretical expectations for a warming climate. This study compares observations and simulations and detects a statistically significant effect of increased greenhouse gases on observed increases in extreme precipitation events over much of the Northern Hemisphere land area.

Human emissions of greenhouse gasses — and related warming — have been shown to be an influence on global and regional warming and on broad-scale precipitation changes. But so far, assessing the human imprint on specific weather events has proven difficult. Now, publicly contributed climate simulations are used to show that increased greenhouse gas emissions substantially increased the risk of flood occurrence during the catastrophic 2000 England and Wales floods.

One approach to sustainable fisheries is that of co-management, in which fishers and managers take joint responsibility for regulation. The evidence that this works is largely anecdotal, so this study systematically examined 130 co-managed fisheries. Several attributes of co-management were required for success, with leadership being the most important. A total of 8 attributes of co-management were required for a successful fishery, and above this number there was a linear relationship between the extent of co-management and success.

When did macroscopic, complex life forms first appear in the fossil record? This study presents spectacular fossils of seaweed-like forms from the approximately 600-million-year-old early Ediacaran of China, a time when the Earth had only just recovered from the worldwide Marinoan glaciation.

A common stem cell is known to produce both neural plate and mesoderm, but the factors regulating this choice are unknown. This study determines that Tbx6-dependent modulation of the developmental transcription factor Sox2 drives the fate of axial stem cells. In the absence of Tbx6, cells aberrantly upregulated Sox2 activity, with the result that cells originally destined to be mesoderm turned into ectopic neural tubes. In the absence of the N1 enhancer, this aberrant regulation is corrected and cells follow the appropriate fate, even in the absence of Tbx6. Therefore, active repression of the neural fate program is essential for mesoderm tissue to develop from axial stem cells.

Gene expression fluctuates in concert with the day/night cycle, and this results in differential behaviours throughout the day. These changes in expression have been studied at the transcriptional and post-translational levels. Here, another type of circadian-influenced regulation that occurs at the post-transcriptional level is defined. The twenty-four (TYF) protein associates with the mRNA of the clock protein PER, enhancing its translation.

Activating AMPK or inactivating calcineurin slows ageing in worms and increases their lifespan. Here it is shown that inhibition of CRTC-1 is required for these life-extending effects. CRTC-1 is the only worm member in the family of CREB-regulated transcriptional co-activators, or CRTCs, and, like the mammalian family members, CRTC-1 interacts with a worm homologue of the CREB transcription factor (CRH-1). Eliminating crtc-1 increases lifespan in a crh-1-dependent manner, as does elimination of crh-1 alone. Downregulation of components in the CRTC/CREB pathway has previously been shown to confer health benefits to mice, complementing their lifespan effects in worms.

This study shows, via a mouse model of intestinal cancer, that in the absence of CKIα, the loss of p53 dramatically enhances tumour progression and metastasis. p53 is shown to normally limit cancer cell invasion via the regulation of p21 and a set of invasion genes that include Prox1. This study adds important insights to the emerging picture that during tumour development the p53 tumour suppressor gene not only controls cell death and proliferation but also metastasis.

Activation of inflammatory gene expression by toll-like receptor (TLR) signalling pathways involves the removal of gene repression complexes such as NCoR. Here, coronin 2A, a component of the NCoR complex, is shown to mediate TLR-induced NCoR turnover and de-repression of inflammatory genes by a mechanism involving interaction with oligomeric nuclear actin.

TDG is a member of the uracil DNA glycosylase family of DNA repair enzymes. It has been implicated in gene regulation but its biological functions have been unclear. Here, a knockout of the Tdg gene in mice reveals functions in embryonic development and in the maintenance of chromatin states.

The US government employs researchers to delve into matters of state. But a special set of soft skills is essential.

Molecular biologist Collins Ouma's efforts to combat paediatric malaria in Kenya are gaining momentum.

Mind games.