Volume 468 Issue 7327, 23 December 2010

Italy's proposed university reform must be linked to performance.

Jane Lubchenco, Nature's Newsmaker of the Year, shows how scientists can help society.

Scientists must reach across the divide and speak up for campus colleagues in arts and humanities departments, says Gregory Petsko.

The week in science.

Mixed reviews greet White House guidelines for preventing political interference in US government science.

Four-year budget protects grants but cuts capital spending.

A distant cousin raises questions about human origins.

Divisions within US National Science Foundation throw plans for underground science facility into crisis.

A round-up of the top science news stories of the past 12 months.

She set out to revolutionize US ocean management — but first she faced the oil spill. Jane Lubchenco is Nature 's Newsmaker of the Year.

When knowledge is uncertain, experts should avoid pressures to simplify their advice. Render decision-makers accountable for decisions, says Andy Stirling.

This year showed that good communication can make you a leader, and a better scientist, says Nancy Baron.

Yvon Le Maho is moved by a powerful account of the demise of the Adélie penguin.

Linus Pauling's book on bonding brought quantum mechanics into practical chemistry, finds Philip Ball.

Ben Shneiderman enjoys a tome full of tools for discovery.

Laura Spinney visits a Versailles exhibition of curiosities.

As Roger Penrose publishes his collected works — six volumes comprising more than 5,000 pages — the mathematical physicist muses on 50 years of groundbreaking research in general relativity, quantum mechanics, cosmology, geometry and consciousness.

The walking encyclopedia of comets.

Analysis of ancient nuclear DNA, recovered from 40,000-year-old remains in the Denisova Cave, Siberia, hints at the multifaceted interaction of human populations following their migration out of Africa. See Article p.1053

Nanowires are candidates for enabling the exchange of quantum information between light and matter. The rapid control of a single electron spin by solely electrical means brings this possibility closer. See Letter p.1084

Protein molecules in solution exist as an equilibrium of different conformations, but the sizes and shifts of these populations cannot be determined from static structures. A report now shows how they can be measured in solution.

The discovery of an inner giant planet in the unusually massive solar system around the star HR 8799 creates an ensemble of planets that is difficult to explain with prevailing theories of planet formation. See Letter p.1080

Impulsivity has been linked to various psychiatric disorders and forms of violent behaviour. A gene mutated in a population of violent Finnish criminal offenders provides clues to the neural basis of this trait. See article p.1061

Protein factors can regulate gene expression by binding to specifically modified DNA-associated proteins. Small molecules that selectively interfere with such interaction may be of therapeutic value. See Article p.1067 & Letter p.1119

Using DNA from a finger bone, the genome of an archaic hominin from southern Siberia has been sequenced to about 1.9-fold coverage. The group to which this individual belonged shares a common origin with Neanderthals, and although it was not involved in the putative gene flow from Neanderthals into Eurasians, it contributed 4–6% of its genetic material to the genomes of present-day Melanesians. A tooth whose mitochondrial genome is very similar to that of the finger bone further suggests that these hominins are evolutionarily distinct from Neanderthals and modern humans.

Impulsive behaviour characterizes several psychiatric diseases and violent behaviour but its origins are complex. Here, exon sequencing focused on fourteen serotonin- and dopamine-related genes identified a mutation in HTR2B, which was associated with psychiatric diseases marked by impulsivity in a Finnish population. The role of this serotonin receptor in impulsivity is further supported by the knockout mouse phenotype.

A new approach is used to target BET family bromodomains which are found in transcriptional regulators where they mediate the recognition of acetyl-lysine chromatin marks. Structural data reveal how the compound JQ1 binds to the bromodomain of BRD4. BRD4 has been implicated in a subtype of human squamous carcinomas, and JQ1 is found to inhibit the growth of BRD4 dependent tumours in mouse models.

To investigate the core engine of the eukaryotic mitotic cycle, a minimal control network has been generated in fission yeast that efficiently sustains cellular reproduction. Orderly progression through the major events of the cell cycle is driven by oscillation of an engineered minimal CDK module lacking much of the canonical regulation.

High-contrast near-infrared imaging of the nearby star HR 8799 has shown three giant planets. Here, the presence of a fourth planet, interior to and about the same mass as the other three, is reported. The system, with this additional planet, represents a challenge for current planet formation models as none of them can explain the in situ formation of all four planets.

Motion of electrons can influence their spins through a fundamental effect called the spin–orbit interaction. Here, a spin–orbit quantum bit (qubit) is implemented in an indium arsenide nanowire, which should offer significant advantages for quantum computing. The spin–orbit qubit is electrically controllable, and information can be stored in the spin. Moreover, nanowires can serve as one dimensional templates for scalable qubit registers, and are suited for both electronic and optical devices.

Electron microscopy has advanced to the stage where individual elements can be identified with atomic resolution. Here it is shown to be possible to get fine-structure spectroscopic information of individual light atoms such as those of carbon, and so also probe their chemical state. This capability is illustrated by investigating the edges of a graphene sample, where it is possible to discriminate between single-, double- and triple-coordinated carbon atoms.

The unusual capability of solid crystalline materials to deform plastically (known as superplasticity) has been found in metals and even ceramics; however, no experimental studies have yet to demonstrate this behaviour in geological materials. It is now demonstrated that some synthetic rocks, which are good analogues for Earth's mantle, undergo homogeneous elongation up to 500% under subsolidus conditions. Calculations show that such superplastic flow in the mantle is inevitably accompanied by significant grain growth that can change fine-grained rocks to coarse-grained aggregates, resulting in increasing mantle viscosity and finally termination of superplastic flow.

Medulloblastomas are the most common malignant childhood brain tumours and are thought to arise from the cerebellum. There is substantial heterogeneity among medulloblastomas and some are thought to arise following aberrant Sonic Hedgehog pathway activation. It is now shown that a distinct subtype of medulloblastoma arises from the dorsal brainstem and is associated with altered WNT signalling. Distinct molecular and clinical profiles of the subtypes have implications for future treatment.

During periods of fasting the liver produces ketone bodies, which the peripheral tissues can use as a source of energy. Here it is shown that fasting inhibits multi-component mTOR complex 1 (mTORC1) in the liver. Inhibition of mTORC1 is required for activation of PPARα, a master regulator that switches on genes involved in ketogenesis. Livers from aged mice have increased mTORC1 signalling, reduced PPARα activity, and reduced ketone production. The observation that mTORC1 promotes an ageing phenotype in the liver fits well with the observation that inhibition of this pathway increases lifespan in several organisms.

The histone variant mH2A is shown to be expressed at reduced levels in many melanomas. Loss of mH2A promotes tumour growth and metastasis via transcriptional upregulation of CDK8, a known oncogene. This study therefore reveals a new tumour suppression mechanism exerted by epigenetic modifications.

Here, germ-band extension in Drosophila is studied in which epithelial cells undergo an ordered process of intercalation resulting in tissue extension through remodelling of cell junctions. Cell junction shrinkage is driven by polarized flow of medial Myosin-II pulses towards junctions which organizes the whole process of intercalation. The flow of Myosin II is driven by the polarized distribution of E-cadherin complexes at adherens junctions. Thus, epithelial morphogenesis is driven by polarized contractile actomyosin flows emerging from interactions between E-cadherin and actomyosin networks.

The enzyme eNOS is crucial for regulating vascular function as it can produce both the vasodilator nitric oxide and the vasoconstrictor superoxide. Here it is shown that a modification associated with oxidant stress, S-glutathionylation, switches the enzyme from forming nitric oxide to forming superoxide. In hypertensive vessels, S-glutathionylation of eNOS is increased and this is associated with impaired endothelium-dependent vasodilation.

Post-translationally modified histones are recognized by effector proteins which contain specific binding modules; for example, the bromodomain-containing BET proteins bind acetylated lysine residues during gene activation. Here a synthetic small molecule is described that interferes with the binding of certain BET family members to acetylated histones. The compound inhibits activation of pro-inflammatory genes in macrophages and has activity in a mouse model of inflammatory disease.

Ubiquitination of histone H2A has been implicated in polycomb-mediated transcriptional silencing, but its precise functions are unclear. Here, ZRF1 is shown to be recruited to ubiquitinated H2A and to function in displacing polycomb-repressive complex 1 (PRC1) from chromatin to facilitate transcriptional activation.

The initial crystal structure of LeuT, together with subsequent functional and structural studies, provided direct evidence for a single, high-affinity substrate-binding site. Recent binding, flux and molecular simulation studies, however, have been interpreted in terms of a model where there are two high-affinity binding sites: the second (S2) site is believed to be located within the extracellular vestibule. Here, direct measurement is performed of substrate binding to wild-type LeuT and to S2 site mutants using isothermal titration calorimetry, equilibrium dialysis and scintillation proximity assays. The conclusion is made that LeuT harbours a single, centrally located, high-affinity substrate-binding site.

Qatar's research machine is a work in progress, but its funding opportunities are already luring international scientists to its increasing number of institutions.

Low salaries and elusive tenure didn't dim the appeal of self-directed research for US scientists last year.

Worlds within worlds.

Researchers are adopting the tools of bioinformatics and pharmaceuticals to study and interpret the ever-growing body of data on the interplay between diet and genes.

Research on the contents of milk and how breast-feeding benefits a growing child is surprising scientists.

Diet-directed evolution shaped our brains, but whether it was meat or tubers, or their preparation, that spurred our divergence from other primates remains a matter of hot debate.

Diet-related illnesses are some of the biggest killers today. Can we tailor our food intake to prevent these diseases? Large international projects are underway to find out.

Several human genes involved in digestion have diverged along cultural lines. Research suggests these adaptations influence the range of foods tolerated and even certain diseases.

The pioneers of nutrition research determined the energy content of food and also helped to overturn misconceptions about various diseases that plagued humankind.

Certain things taste differently to different people. Why is this, and does this affect our choice of food?

Genetic studies of people conceived during famine reveals that prenatal malnutrition lingers long after the event.

Health biomarkers, smart technology and social networks are hastening an era of nutrition tailored to your individual needs but relying on information generated by the crowd.

Food has a profound effect on our health. From the first milk we take, to the vast array of culinary creations that give us both pleasure and sustenance, our genes influence our diets — and vice versa. This complex interplay has shaped human evolution. Nutrigenomics will help us exploit this relationship, blurring the boundaries between food and medicine, and heralding an era of personalized nutrition.