Volume 462 Issue 7273, 3 December 2009

Stolen e-mails have revealed no scientific conspiracy, but do highlight ways in which climate researchers could be better supported in the face of public scrutiny.

The week in science

The world's top emitter pledges cuts, but "substantial societal reforms" are needed to make them.

Climatologists remain sanguine over incident.

Infrastructure programme steers substantial resources to major cities, upsetting some regional centres.

Obama launches wide-ranging advisory body.

Early departure sparks fears over future of funding agency.

Climate summit will seek ways to help developing nations build a low-carbon energy infrastructure.

Nobel laureates and leading researchers rally to protest at proposed spending cuts.

Immune system gets a boost from early exposure to bacteria.

An underwater effort to detect subatomic particles has ended up detecting sperm whales instead. Nicola Nosengo reports on a partnership between marine biologists and particle physicists.

A unique collaboration is bringing automated screening to the study of fly behaviour and could change the way that machines see humans. Lizzie Buchen reports.

An innovative approach to reducing toxic-chemical use scrambles to stay alive as big science prospers, says Daniel Sarewitz.

In the first of two pieces on reducing greenhouse-gas emissions, Gert Jan Kramer and Martin Haigh analyse historic growth in energy systems to explain why deploying alternative technologies will be a long haul.

In the second of two pieces on decarbonization, Isabel Galiana and Christopher Green argue that fostering a technology revolution, not setting emissions targets, is the key to stabilizing the climate.

The story of Earth's glaciers and ice caps is key to understanding climate science, but this kaleidoscopic account lacks a strong narrative, argues Johannes Oerlemans.

The hunt for the receptor for abscisic acid, initially marked by false starts and lingering doubts, has met with success. Converging studies now reveal the details of how this plant hormone transmits its message.

The weakest interactions of protein complexes are thought to be lost when such assemblies are removed from their natural, watery environments. Not so, reveals a study in the vacuum chamber of a mass spectrometer.

A decades-old theory of stellar evolution — that the most massive stars end their life in a peculiar type of explosion termed a pair-instability supernova — finally seems to have been confirmed by observations.

Following inflammation or nerve injury, stimuli that are normally perceived as innocuous can evoke persistent pain. A population of neurons that contributes to this syndrome has now been identified.

The ring-shaped helicase enzyme Rho moves along RNA using ATP as an energy source. Coordinating ATP hydrolysis with nucleic-acid binding seems to determine the direction and mechanism of helicase movement.

An elegant experiment shows that atoms subjected to a pair of laser beams can behave like electrons in a magnetic field, as demonstrated by the appearance of quantized vortices in a neutral superfluid.

The study of fast and intricate enzyme reactions requires methods that have the speed and sophistication to match. Such an approach reveals the way in which proteins are tagged with ubiquitin for destruction.

Overexpression of certain transcription factors can reprogram somatic cells into induced pluripotent stem (iPS) cells; however, only a minority of donor somatic cells can be reprogrammed to pluripotency. Here, this reprogramming is shown to be a continuous stochastic process where almost all mouse donor cells eventually give rise to iPS cells on continued growth and transcription factor expression; changing certain parameters results in accelerated iPS cell formation.

The plant hormone abscisic acid (ABA) is a regulator of plant growth, development and responses to environmental stresses. Recently, the PYR/PYL/RCAR family of START proteins was found to bind ABA and mediate inactivation of downstream effectors. The crystal structures of apo and ABA-bound receptors as well as a ternary PYL2–ABA–PP2C complex is now reported and analysed, revealing a gate–latch–lock mechanism underlying ABA signalling.

The plant hormone abscisic acid (ABA) is a regulator of plant growth, development and responses to environmental stresses. Within plants, the PYR/PYL/RCAR family of START proteins receives ABA to inhibit the phosphatase activity of the group-A protein phophatases 2C (PP2Cs). Here, the crystal structures of ABA bound to its receptor PYL1 and a complex formed between ABA, PYL1 and the PP2C protein ABI1 are presented, shedding light on the structural basis of ABA signalling.

Conjugation of ubiquitin chains onto proteins is an important post-translational modification that regulates the stability, localization and activity of substrate proteins. A series of enzymes known as E1, E2 and E3 mediate assembly of ubiquitin chains but the pathway remains unclear. Theoretical and experimental methodologies are now introduced to study the formation of ubiquitin chains at millisecond time resolution, demonstrating that substrate polyubiquitylation proceeds sequentially.

Super-massive black holes in active galaxies can accelerate particles to relativistic energies, producing jets with associated γ-ray emission. Galactic 'microquasars' also produce relativistic jets; however, apart from an isolated event detected in Cygnus X-1, there has hitherto been no systematic evidence for the acceleration of particles to gigaelectronvolt or higher energies in a microquasar. Here, a report of four γ-ray flares with energies above 100 MeV from the microquasar Cygnus X-3 illuminates this important problem.

Extremely massive stars with initial masses of more than 140 solar masses end their lives when pressure-supporting photons turn into electron–positron pairs, leading to a violent contraction that triggers a nuclear explosion, unbinding the star in a pair-instability supernova. Here, the mass of the exploding core of supernova SN 2007bi is estimated at around 100 solar masses, in which case theory unambiguously predicts a pair-instability supernova. Further observations are well fitted by models of pair-instability supernovae.

Atomic Bose–Einstein condensates can be used to study many-body phenomena that occur in more complex material systems; however, the charge neutrality of these systems prevents intriguing phenomena that occur for charged particles in a magnetic field. Rotation can be used to create a synthetic magnetic field, but such fields are of limited strength. An optically synthesized magnetic field for ultracold neutral atoms that is not subject to the limitations of rotating systems is now experimentally realized.

Optical forces can be used to manipulate small objects; for instance, in optical tweezers. However, it is challenging to manipulate the optical response of photonic structures using optical forces because of the large forces that are required to induce appreciable changes in the geometry of the structure. Here, a resonant structure made of silicon nitride is demonstrated whose optical response can be efficiently statically controlled using relatively weak attractive and repulsive optical forces.

Extensive records exist with which to assess the relationship between external climate forcings — such as changes in insolation — and climate variability for middle and high latitudes, but records from equatorial regions are relatively few, especially from regions experiencing the passage of the Intertropical Convergence Zone. A continuous and well-resolved climate-proxy record of hydrological variability during the past 25,000 years from equatorial East Africa is now presented and analysed.

The Gutenberg–Richter relation and the Omori–Utsu law, both power laws, are two of the long-standing relationships of statistical seismology. Here, aftershock sequences are described according to the faulting style of their main shocks, showing that the time delay before the onset of the power-law aftershock decay rate is on average shorter for thrust main shocks than for normal fault earthquakes. These similar dependences on the faulting style indicate that both the fundamental power laws are governed by the state of stress.

The lateral hypothalamic area is the 'feeding centre' in the brain. During fasting, the neuropeptides orexin and melanin-concentrating hormone (MCH) are released in this area and stimulate food intake. The expression of orexin and MCH is now shown to be regulated by the transcription factor Foxa2, a downstream target of insulin signalling. The results show that Foxa2 can act as a metabolic sensor to integrate metabolic signals, adaptive behaviour and physiological responses.

Despite the contribution of mechanical pain to the morbidity associated with inflammation and trauma, the primary sensory neurons that convey this sensation have not been identified. Using knockout mice, the loss of the low abundance vesicular glutamate transporter VGLUT3, expressed by a small subset of peripheral sensory neurons projecting to areas implicated in persistent pain caused by injury, is now shown to specifically impair mechanical pain sensation.

Existing DNA sequence databases carry only a tiny fraction of the total amount of DNA sequence space from bacterial species. Bioinformatics searches of genomic DNA from bacteria commonly identify new noncoding RNAs (ncRNAs) such as riboswitches. Here, an updated computational pipeline is used to discover ncRNAs that rival the known large ribozymes in size and structural complexity; other such RNAs probably remain to be discovered.

The plant hormone abscisic acid (ABA) is a regulator of plant growth, development and responses to environmental stresses. Although several proteins have been reported to function as ABA receptors and many more are known to be involved in ABA signalling, the identities of ABA receptors remain controversial and the mechanism of signalling unclear. ABA-mediated signalling is now reconstituted in vitro, defining a minimal set of core components of the pathway.

The plant hormone abscisic acid (ABA) has, among other things, a central role in coordinating the adaptive response in situations of decreased water availability. A family of intracellular ABA receptors, named PYR/PYL/RCAR, has recently been identified. Here, the crystal structure of Arabidopsis thaliana PYR1, which consists of a dimer in which one of the subunits is bound to ABA, is presented.

X-ray crystallography and NMR spectroscopy are two powerful tools to determine the three-dimensional structures and characterize the dynamic properties of proteins. The two methods are now combined to structurally unravel interconverting substrates of a human proline isomerase. Crystallographic approaches are used to define minor protein conformations and, combined with NMR analysis, to show how collective motions contribute to the catalytic power of an enzyme.

Overcoming the limitations of spatial and temporal resolution to image within a cell is no easy feat. Kelly Rae Chi examines the latest diffraction-busting technologies.

Jorge Gardea-Torresdey of the University of Texas-El Paso received the 2009 Distinguished Scientist Award from the Society for the Advancement of Chicanos and Native Americans.

As a boy, I dreamed of building a sled. Now I build research papers.

Proportion of US women earning science and engineering doctorates rises.

Small grants will help synthetic-biology researchers delve into emerging field.

Non-profit, personalized medicine centre expects to hire some 350 researchers.

The growing field of synthetic biology is attracting hard-core scientists and amateurs alike. Bryn Nelson reports.

The art of conversation.