Volume 462 Issue 7276, 24 December 2009

Nature is pleased to name physicist Steven Chu, Nobel laureate and the US Secretary of Energy, as its Newsmaker of the Year.

The agreement reached last week lends fresh urgency to challenges in science and communication.

The year in which …

The week in science

A weak international climate agreement leaves room for science to shape the next round of negotiations.

Signals may be first evidence of elusive particles.

Five years after the Indian Ocean disaster, the technology is in place, but local preparedness is less advanced.

E-mail made threats and demanded money.

University finds that researcher falsified data supporting 11 protein structures.

Take a tour through the images that defined 2009, from the murkiest depths of the oceans, where warring worms pepper their enemies with glowing bombs, to the spectacular swirling rainbows thousands of light years away at the heart of the Milky Way. This year has provided a pictorial panoply, with dust-filled volcanic eruptions captured on film by luck, the tiniest of toads at risk of being lost forever and humankind's outpost in space picked out in detail as it passes in front of the Sun.

As a physicist, he found a way to capture atoms and won a Nobel prize. Now he is marshalling scientists and engineers to transform the world's biggest energy economy. Eric Hand profiles the US energy secretary, Nature's Newsmaker of the Year.

A gripping account of the spread of the bird flu virus across southeast Asia holds lessons for the global management of pandemics such as swine flu, explains Ab Osterhaus.

Kepler's interpretation of the supernova of 1604, De Stella Nova, interwove the science of astronomy with astrology and theology in an attempt to determine the correct birthdate of Jesus, explains Martin Kemp.

Nature invited some of its regular reviewers to name their pick of this year's book publications.

Dietary restriction promotes longevity but impairs fecundity in many organisms. When the amino acids in a diet are fine-tuned, however, lifespan can be increased without loss of fecundity — at least in fruitflies.

An array of air bubbles in a rubber-like material can be made to block the transmission of sound. This finding might help in the design of soundproof walls for music rooms and urban apartments.

Observations of star clusters in the Milky Way show that collisions between stars as well as mass flow within binary systems can explain how the peculiar family of blue straggler stars came to be born.

DNA transfer across membranes is a fundamental life process. The structure of part of a protein channel that performs this task offers insight into the mechanism of DNA passage through bacterial cell envelopes.

Transistors have been made from single molecules, where the flow of electrons is controlled by modulating the energy of the molecular orbitals. Insight from such systems could aid the development of future electronic devices.

Nobel-prizewinning success in physics achieved in the Soviet system.

Multiple somatic rearrangements are often found in cancer genomes, but the underlying processes of rearrangement and the effects of this are unclear. A paired-end sequencing strategy is now used to map somatic rearrangements in human breast cancer genomes. More rearrangements in some breast cancers are found than previously recognized, including frequent tandem duplications that may reflect a specific defect in DNA maintenance.

Type IV secretion systems span the two membranes of Gram-negative bacteria, with three proteins —— VirB7, VirB9 and VirB10 — assembled into a 1.05 megadalton core spanning the inner and outer membranes. Here, the crystal structure of an outer-membrane complex is presented. The structure is the largest determined for an outer-membrane channel and is unprecedented in being composed of three proteins.

The ATP-dependent chromatin assembly factor (ACF) generates and maintains nucleosome spacing by constantly moving a nucleosome towards the longer flanking DNA faster than the shorter flanking DNA. But how the enzyme moves back and forth between both sides of a nucleosome to accomplish bidirectional movement is unknown. Nucleosome movement is now shown to depend cooperatively on two ACF molecules, indicating that ACF functions as a dimer of ATPases.

The ATP-dependent chromatin assembly factor (ACF) generates regularly spaced nucleosomes, but the mechanism by which ACF mobilizes nucleosomes remains poorly understood. Here, single-molecule FRET is used to monitor the remodelling of individual nucleosomes by ACF in real time; the study reveals previously unknown remodelling intermediates and dynamics, and indicates that ACF is a highly processive and bidirectional nucleosome translocase.

'Blue straggler' stars lie on or near the main sequence of star clusters and are sufficiently massive that they should have evolved into white dwarfs long ago. Two possible mechanisms have been proposed for their formation: mass transfer between binary companions and stellar mergers resulting from direct collisions between two stars. Here, two distinct parallel sequences of blue stragglers are reported in the globular cluster M 30, one arising from the evolution of close binaries, the other from direct collisions.

'Blue straggler' stars lie on or near the main sequence of star clusters and are sufficiently massive that they should have evolved into white dwarfs long ago. Statistical evidence indicates that in globular star clusters the blue stragglers probably form from binary stars. Here, 76 per cent of the blue stragglers in the open cluster NGC 188 are found to be currently in binary systems, a three times higher frequency than that among normal solar-type main-sequence stars.

Although magnetic fields have an important role in the evolution of gas clouds in the Galaxy, the strength and orientation of the field in the interstellar medium near the heliosphere has been poorly constrained, with previous estimates varying widely and based on indirect observational inferences or modelling. Measurements of the deflection of the solar wind plasma flows in the heliosheath are now used to determine the magnetic field strength and orientation in the interstellar medium.

A longstanding aim in molecular-scale electronics is to create a true transistor analogue in which charge transport through a molecule is directly controlled by external modulation of the molecular orbitals. The observation of such a solid-state molecular device is now reported. The data demonstrate that true molecular transistors can be created, and clear the way for molecularly engineered electronic devices.

Coastal ecosystems are sensitive to changes in the quantity and lability of terrigenous dissolved organic matter (DOM) delivered by rivers. The lability of DOM is thought to decrease with age, but this view stems from work in watersheds where terrestrial plant and soil sources dominate streamwater DOM. Here, glaciated watersheds on the Gulf of Alaska are shown to be a source of old but labile dissolved organic matter, suggesting that glacial runoff is an important source of labile reduced carbon to marine ecosystems.

Non-volcanic tremor was discovered nearly a decade ago; however, a thorough explanation of the geologic process responsible for tremor generation has yet to be determined. A robust correlation is now identified between extremely small, tidally induced shear stress parallel to the San Andreas fault and non-volcanic tremor activity near Parkfield, California. Such tremor may represent shear failure on a critically stressed fault in the presence of near-lithostatic pore pressure.

As the climate changes, species will have to move if they are to remain in an area with the same average temperature. Here, this required movement — termed the velocity of temperature change — is quantified. The results indicate management strategies for minimizing biodiversity loss from climate change and suggest that montane landscapes may effectively shelter many species into the next century.

There are now nearly 1,000 completed bacterial and archaeal genomes available, but as most of them were chosen for sequencing on the basis of their physiology, the data are limited by a highly biased phylogenetic distribution. To explore the value added by choosing microbial genomes for sequencing on the basis of their evolutionary relationships, the genomes of 56 species of Bacteria and Archaea selected to maximize phylogenetic coverage are now sequenced and analysed.

Dietary restriction extends healthy lifespan in diverse organisms but reduces fecundity; this is thought to be because of an adaptive reallocation of nutrients from reproduction to somatic maintenance. Here, the nutrients producing the responses of lifespan and fecundity to dietary restriction in Drosophila are identified. Adding essential amino acids to the dietary restriction condition increased fecundity and decreased lifespan; furthermore, addition of methionine alone rescued fecundity.

Dendritic spines carry the majority of excitatory synapses, and spine morphology and distribution are critical for synaptic transmission, synaptic integration and plasticity. Here, signalling by the secreted semaphorin Sema3F is shown to control spine distribution along select dendritic processes, and distinct secreted semaphorin signalling events orchestrate CNS connectivity through the differential control of a variety of processes.

Non-small-cell lung cancers with activating mutations in the epidermal growth factor receptor (EGFR) often show a clinical response to EGFR kinase inhibitors but tend to develop drug-resistance mutations, including the gatekeeper T790M mutation. Here, a new class of EGFR inhibitors is developed; these agents are 30- to 100-fold more potent against EGFR with the T790M mutation, and up to 100-fold less potent against wild-type EGFR, than current EGFR inhibitors.

Over the past decade, several techniques have been developed to improve the detection of small amounts of DNA and RNA molecules, but detection of DNA molecules at concentrations below the femtomolar level requires amplified detection schemes. A unique nanomechanical response of hybridized DNA and RNA molecules that serves as an intrinsic molecular label is now reported; nanomechanical measurements allow direct detection and counting of hybridized molecules.

Despite the progress that has been made in designing proteins that mimic native proteins structurally, it is difficult to design functional proteins and particularly challenging to design metalloproteins that reproduce both the structure and function of native metalloenzymes. Here, the successful, rational design of a structural and functional model of a metalloprotein — nitric oxide reductase — is achieved.

Martin Cole takes over as chief of food and nutritional sciences at the Commonwealth Scientific and Industrial Research Organisation in Australia in January 2010.

Research fellowship is looking for energy innovators.

Michigan biomedical research institute opens new lab space.

Where the cuts hit in 2009.

An act of faith.