実験室の安全性を高める取り組みを、真剣に進めるべきときだ。

Safety catch p.5

International laboratory survey offers comfort — and caution.

doi: 10.1038/493005b

科学者の研究への寄与を包括的にとらえ、明示するよう、改善を図る必要がある。

In search of credit p.5

Explicit recognition of researchers’ contributions to science is becoming more comprehensive. Not before time — especially as a means of crediting referees.

doi: 10.1038/493005a

気の緩みが実験室の安全の落とし穴に。

Safety survey reveals lab risks p.9

Questionnaire suggests researchers not as safe as they feel.

doi: 10.1038/493009a

彗星の接近から特許紛争やオープンアクセス出版まで、Natureが予測する2013年の科学界のビッグニュースは？

New year, new science p.11

Nature looks ahead to the key findings and events that may emerge in 2013.

doi: 10.1038/493011a

環境にやさしいとされる天然ガスだが、その生産に伴うメタン漏出量の多さに疑念が。

Methane leaks erode green credentials of natural gas p.12

Losses of up to 9% show need for broader data on US gas industry’s environmental impact.

doi: 10.1038/493012a

訃報：Maxine Clarke（Nature publishing executive editor）

Obituary: Maxine Clarke p.13

doi: 10.1038/493013b

米国の財政の崖は土壇場で回避されたが、依然として、科学予算にも削減の懸念が。

US fiscal deal leaves science vulnerable p.13

Congress delays mandatory cuts to agencies.

doi: 10.1038/493013a

健康：結核の報復

TB's revenge p.14

世界は結核との闘いに勝利をおさめつつあったが、薬剤耐性菌が新たな脅威になり始めている。

doi: 10.1038/493014a

フォーラム：古生物学：陸に上がった生物の化石

Palaeontology: Fossils come in to land p.28

オーストラリアでエディアカラ紀の岩石中から見つかった化石は、これまで初期の海洋性生物のものだとされてきた。しかし、これらの岩石は実は化石化した土壌だと示唆する報告がある。では、このようなエディアカラ紀の生物の一部は実際には地衣類のような陸生生物だったのだろうか。古生物学者と地質学者がこうした証拠を慎重に検証している。

doi: 10.1038/nature11765

計算材料科学：柔らかい堆積と塊状の結晶

Computational materials science: Soft heaps and clumpy crystals p.30

変形しうる粒子の充填挙動の詳細なシミュレーションから、ソフトマターは高密度になると従来とは異なる結晶構造をとりうるのかどうかという問題に対して、取りうるという答えが得られ、論争は結着した。そして今、実際の例を探す競争が始まっている。

doi: 10.1038/493030a

天文学：アンドロメダから広がる矮銀河の円盤

Astronomy: Andromeda's extended disk of dwarfs p.31

アンドロメダ銀河とその周辺の深部画像観測により、アンドロメダ銀河の周りを同じ方向に周回している衛星銀河群が形成する、広いが薄い平面構造が明らかになった。

doi: 10.1038/493031a

発生生物学：相対的な大きさが一定に保たれた体節

Developmental biology: Segmentation within scale p.32

体の各部分の相対的なサイズは、生物の体のサイズとは関係なしに、一定に保たれている。実験モデルの1つは、脊椎動物では体節形成のサイズに依存した調整と遺伝子の周期的発現が起こっていることを明らかにしている。

doi: 10.1038/nature11849

構造生物学：膜酵素プレセニリンの構造

Structural biology: Membrane enzyme cuts a fine figure p.34

細胞膜内のタンパク質の切断を行う酵素であるプレセニリンの機能異常は、アルツハイマー病につながることがある。微生物のプレセニリンの結晶構造から、この酵素ファミリーの働きについての手がかりが得られた。

doi: 10.1038/nature11768

気候変動：タイミングがすべて

Climate change: All in the timing p.35

全球的な温暖化の抑制にかかわるさまざまな要因は、それぞれどの程度の影響を及ぼすのだろうか。温度上昇を2°Cまでに制限する確率には、排出削減のタイミングが最も影響が大きいことが、1つの研究で明らかにされた。

doi: 10.1038/493035a

微生物学：壁の崩壊

Microbiology: Break down the walls p.36

ナノスケールの画像化によって、微生物と菌類の酵素は、植物細胞壁を破壊する際の機序が異なることが明らかになった。この知見は、バイオマスからのバイオ液体燃料生産の効率を上げる方法についての手がかりとなるかもしれない。

doi: 10.1038/493036a

物性：強く相互作用する電子の非フェルミ液体d波金属相

Non-Fermi-liquid d-wave metal phase of strongly interacting electrons p.39

Developing a theoretical framework for conducting electronic fluids qualitatively distinct from those described by Landau’s Fermi-liquid theory is of central importance to many outstanding problems in condensed matter physics. One such problem is that, above the transition temperature and near optimal doping, high-transition-temperature copper-oxide superconductors exhibit ‘strange metal’ behaviour that is inconsistent with being a traditional Landau Fermi liquid. Indeed, a microscopic theory of a strange-metal quantum phase could shed new light on the interesting low-temperature behaviour in the pseudogap regime and on the d-wave superconductor itself. Here we present a theory for a specific example of a strange metal—the ‘d-wave metal’. Using variational wavefunctions, gauge theoretic arguments, and ultimately large-scale density matrix renormalization group calculations, we show that this remarkable quantum phase is the ground state of a reasonable microscopic Hamiltonian—the usual t–J model with electron kinetic energy t and two-spin exchange J supplemented with a frustrated electron ‘ring-exchange’ term, which we here examine extensively on the square lattice two-leg ladder. These findings constitute an explicit theoretical example of a genuine non-Fermi-liquid metal existing as the ground state of a realistic model.

doi: 10.1038/nature11732

遺伝：ヒトの腸内微生物叢ゲノムの多様性の全体像

Genomic variation landscape of the human gut microbiome p.45

Whereas large-scale efforts have rapidly advanced the understanding and practical impact of human genomic variation, the practical impact of variation is largely unexplored in the human microbiome. We therefore developed a framework for metagenomic variation analysis and applied it to 252 faecal metagenomes of 207 individuals from Europe and North America. Using 7.4 billion reads aligned to 101 reference species, we detected 10.3 million single nucleotide polymorphisms (SNPs), 107,991 short insertions/deletions, and 1,051 structural variants. The average ratio of non-synonymous to synonymous polymorphism rates of 0.11 was more variable between gut microbial species than across human hosts. Subjects sampled at varying time intervals exhibited individuality and temporal stability of SNP variation patterns, despite considerable composition changes of their gut microbiota. This indicates that individual-specific strains are not easily replaced and that an individual might have a unique metagenomic genotype, which may be exploitable for personalized diet or drug intake.

doi: 10.1038/nature11711

免疫：CCR5は黄色ブドウ球菌のロイコトキシンEDの受容体である

CCR5 is a receptor for Staphylococcus aureus leukotoxin ED p.51

Pore-forming toxins are critical virulence factors for many bacterial pathogens and are central to Staphylococcus aureus-mediated killing of host cells. S. aureus encodes pore-forming bi-component leukotoxins that are toxic towards neutrophils, but also specifically target other immune cells. Despite decades since the first description of staphylococcal leukocidal activity, the host factors responsible for the selectivity of leukotoxins towards different immune cells remain unknown. Here we identify the human immunodeficiency virus (HIV) co-receptor CCR5 as a cellular determinant required for cytotoxic targeting of subsets of myeloid cells and T lymphocytes by the S. aureus leukotoxin ED (LukED). We further demonstrate that LukED-dependent cell killing is blocked by CCR5 receptor antagonists, including the HIV drug maraviroc. Remarkably, CCR5-deficient mice are largely resistant to lethal S. aureus infection, highlighting the importance of CCR5 targeting in S. aureus pathogenesis. Thus, depletion of CCR5+ leukocytes by LukED suggests a new immune evasion mechanism of S. aureus that can be therapeutically targeted.

doi: 10.1038/nature11724

構造生物学：プレセニリンファミリーの膜内アスパラギン酸プロテアーゼの構造

Structure of a presenilin family intramembrane aspartate protease p.56

Presenilin and signal peptide peptidase (SPP) are intramembrane aspartyl proteases that regulate important biological functions in eukaryotes. Mechanistic understanding of presenilin and SPP has been hampered by lack of relevant structural information. Here we report the crystal structure of a presenilin/SPP homologue (PSH) from the archaeon Methanoculleus marisnigri JR1. The protease, comprising nine transmembrane segments (TMs), adopts a previously unreported protein fold. The amino-terminal domain, consisting of TM1–6, forms a horseshoe-shaped structure, surrounding TM7–9 of the carboxy-terminal domain. The two catalytic aspartate residues are located on the cytoplasmic side of TM6 and TM7, spatially close to each other and approximately 8 Å into the lipid membrane surface. Water molecules gain constant access to the catalytic aspartates through a large cavity between the amino- and carboxy-terminal domains. Structural analysis reveals insights into the presenilin/SPP family of intramembrane proteases.

doi: 10.1038/nature11801

宇宙：アンドロメダ銀河の周りを軌道運動している共回転する矮小銀河の巨大で薄い平面

A vast, thin plane of corotating dwarf galaxies orbiting the Andromeda galaxy p.62

About half of the satellites in the Andromeda galaxy (M 31), all with the same sense of rotation about their host, form a planar subgroup that is extremely wide but also very thin.

doi: 10.1038/nature11717

宇宙：天の川銀河中心から放出される磁化した巨大なアウトフロー

Giant magnetized outflows from the centre of the Milky Way p.66

Two giant, linearly polarized radio lobes have been found emanating from the Galactic Centre, and are thought to originate in a biconical, star-formation-driven outflow from the Galaxy’s central 200 parsecs that transports a huge amount of magnetic energy, about 10⁵⁵ ergs, into the Galactic halo

doi: 10.1038/nature11734

物性：誘電体における光場に誘起された電流

Optical-field-induced current in dielectrics p.70

Exposing a fused silica sample to a strong, waveform-controlled, few-cycle optical field increases the dielectric’s optical conductivity by more than 18 orders of magnitude in less than 1 femtosecond, allowing electric currents to be driven, directed and switched by the instantaneous light field.

doi: 10.1038/nature11567

物性：誘電体を光の電場で制御する

Controlling dielectrics with the electric field of light p.75

The ultrafast reversibility of changes to the electronic structure and electric polarizability of a dielectric with the electric field of a laser pulse, demonstrated here, offers the potential for petahertz-bandwidth optical signal manipulation.

doi: 10.1038/nature11720

気候：気候変動の緩和に必要な費用の確率的な見積もり

Probabilistic cost estimates for climate change mitigation p.79

Modelling that integrates the effects of uncertainties in relevant geophysical, technological, social and political factors on the cost of keeping transient global temperature increase to below certain limits shows that political choices have the greatest effect on the cost distribution.

doi: 10.1038/nature11787

地球：マントルの酸化状態と地球内部からの炭素の抽出

The oxidation state of the mantle and the extraction of carbon from Earth’s interior p.84

The oxygen fugacity of the deepest rock samples from Earth’s mantle is found to be more oxidized than previously thought, with the result that carbon in the asthenospheric mantle will be hosted as graphite or diamond but will be oxidized to produce carbonate melt through the reduction of Fe³⁺ in silicate minerals during upwelling.

doi: 10.1038/nature11679

進化：エディアカラ紀の陸上生物

Ediacaran life on land p.89

A new interpretation of fossilized soils (palaeosols) suggests that at least some Ediacaran (625–542 million years ago) organisms lived on land; thus these Ediacaran fossils were not animals, but a fungus-dominated terrestrial biota that predated vascular plants by about 100 million years.

doi: 10.1038/nature11777

知覚：反響定位を行うコウモリで見られる音響視野の収斂

Convergent acoustic field of view in echolocating bats p.93

Studying six vespertilionid bat species of different sizes to investigate the reason why smaller bats have higher frequency echolocation calls, a model is put forward that the size/frequency range is modulated by the need to maintain a focused, highly directional echolocation beam.

doi: 10.1038/nature11664

脳：覚醒下の大脳皮質の知覚応答は抑制が主体である

Inhibition dominates sensory responses in the awake cortex p.97

Visual responses during wakefulness are dominated by inhibition, and this inhibition shapes visual selectivity by restricting the temporal and spatial extent of neural activity.

doi: 10.1038/nature11665

発生：位相勾配がコードする胚パターン形成のスケーリング

Scaling of embryonic patterning based on phase-gradient encoding p.101

An ex vivo primary culture assay is developed that recapitulates mouse embryonic mesodermal patterning and segment formation; using this approach, it is shown that oscillating gene activity is central to maintain stable proportions during development.

doi: 10.1038/nature11804

細胞：YAPによる腸幹細胞の増殖と再生応答の制限

Restriction of intestinal stem cell expansion and the regenerative response by YAP p.106

YAP has previously been identified as an oncogene that promotes cell growth, but now it is shown to restrict stem cell expansion during regeneration in the mouse intestine, suggesting that it may function as a tumour suppressor in colon cancer.

doi: 10.1038/nature11693

免疫：Ca²⁺は脂質の電荷特性を変化させることによってT細胞受容体の活性化を調節する

Ca2+ regulates T-cell receptor activation by modulating the charge property of lipids p.111

Calcium–lipid electrostatic interactions are shown to amplify the tyrosine phosphorylation of CD3ε and CD3ζ in T-cell antigen receptor complex.

doi: 10.1038/nature11699

細胞：SAPKによる複製と転写の協調制御はゲノムの完全性を守っている

Coordinated control of replication and transcription by a SAPK protects genomic integrity p.116

Upregulation of gene transcription in stressed cells can lead to clashes between the transcription and repair machineries; here, a stress-activated protein kinase (SAPK), Hog1, is shown to coordinate these two processes in yeast.

doi: 10.1038/nature11675

細胞：DNA修復足場タンパク質はアダプターRad9に対抗することにより、チェックポイントシグナル伝達を抑制する

DNA-repair scaffolds dampen checkpoint signalling by counteracting the adaptor Rad9 p.120

DNA damage or replication stress induces the activation of checkpoint kinases, pausing the cell cycle so that DNA repair can take place; checkpoint activation must be regulated to prevent the cell-cycle arrest from persisting after damage is repaired, and now the Slx4–Rtt107 complex is shown to regulate checkpoint kinase activity by directly monitoring DNA-damage signalling.

doi: 10.1038/nature11658