Editorials
地表の水の変化の大半は、人為的原因によるものであり、水の管理は最優先課題だ。
Get water governance on the global agenda p.169
Human activity causes most changes in Earth’s surface water, so policies for its governance must become a priority.
doi: 10.1038/540169b
ペットの動物を対象とした臨床試験は、ペット用医薬品はもとよりヒトの医薬品開発にも有用であり、こうした試験を妨げる過剰な規制は見直すべきだ。
Reform regulations to make pet clinical trials easier p.169
Trials in animals can aid both veterinary and human medicine, but complicated rules can stifle them.
doi: 10.1038/540169a
子どもの心に響き、科学への憧れを生む本がある。
Turn children on to science through reading p.170
Books have the power to trigger a lifelong urge to know more about the world and its environs.
doi: 10.1038/540170a
News
欧州宇宙機関(ESA)の火星探査計画「エクソマーズ」の第一弾の着陸機は失敗したが、第二弾の探査機には予定通り予算が。
Europe’s first Mars rover gets funding — despite crash of test craft p.177
But the European Space Agency's participation in a mission to deflect an asteroid moon is now cancelled.
doi: 10.1038/nature.2016.21091
ゲノム解読により、アメリカ先住民の起源をめぐる論争に決着が。
North America’s oldest mummy returned to US tribe after genome sequencing p.178
DNA proves Native American roots of 10,600-year-old skeleton.
doi: 10.1038/540178a
メキシコでのヒト胚研究が、当局による生殖医療の規制強化によって禁止される恐れが。
Mexico proposal to ban human-embryo research would stifle science p.180
Researchers in the country have only just started using homegrown human embryonic stem cells
doi: 10.1038/540180a
米国のポスドク研究者の賃上げは、残業手当に関する法的争いのせいで棚上げに。
Battle over US overtime pay rules leaves many postdocs in limbo p.181
Institutions struggle to respond after court blocks regulations that would have increased wages for junior researchers.
doi: 10.1038/nature.2016.21084
ブラジルのアマゾンの森林破壊が、過去8年で最悪に。
Deforestation spikes in Brazilian Amazon p.182
Illegal land clearing hits highest levels since 2008 as environmental policies come under attack.
doi: 10.1038/nature.2016.21083
英国のEU離脱や米国大統領選などに見られるナショナリズムの再燃の要因について、研究者たちが当惑を。
Researchers baffled by nationalist surge p.182
Economic woes wrought by globalization are only part of the cause.
doi: 10.1038/540182a
News Features
ゲノミクス:囚われの果ての「自由」
What DNA reveals about St Helena’s freed slaves p.184
英国領セントヘレナ島には、アフリカから運ばれる途中で解放され死んでいった多くの奴隷たちの墓があり、そうした死者のDNA解析から、出身地域や死因などが明らかになりつつある。
doi: 10.1038/540184a
News & Views
フォーラム:気候科学:グリーンランドの氷の歴史
Climate science: The history of Greenland's ice p.202
グリーンランドの氷床が完全に溶けてしまえば、全球の海水準は数メートル上昇するだろう。2つの研究で、氷床の過去の挙動に基づいて、温暖化した地球でのこの氷床の脆弱性の評価が行われたが、その結論は一見したところ矛盾するものだった。2人の地球化学者と1人の氷河学研究者がこの問題について論じている。
doi: 10.1038/540202a
ウイルス学:寄生体に寄生するものが宿主の隣人を助ける
Virology: A parasite's parasite saves host's neighbours p.204
ウイルスは、寄生性ウイルス(ウイルスに寄生し細胞資源に関して競合する)に攻撃されることがある。そのような寄生性ウイルスの1つが、宿主細胞集団をウイルスの攻撃から守ることがあるのが今回明らかになった。
doi: 10.1038/540204a
天体物理学:宇宙時間にわたる元素存在量
Astrophysics: Elemental abundances across cosmic time p.205
初期宇宙に存在した大質量銀河の1つの化学組成によって、非常に短い星形成期間が明らかになった。この結果は銀河と宇宙自体の進化についての我々の考え方に疑問を投げ掛けるものだ。
doi: 10.1038/540205a
神経変性疾患:アルツハイマー病での神経の同期
Neurodegenerative Disorders: Neural synchronization in Alzheimer's disease p.207
アルツハイマー病では、神経回路によって発生する電気的振動が破壊される。この病気のマウスモデルで、この振動を回復させると免疫細胞が活性化され、病気と関連するとされているアミロイドβタンパク質が脳から除去されることが今回明らかになった。
doi: 10.1038/540207a
回顧:地球の公転軌道と氷河期が結び付けられてからの40年
In Retrospect: Forty years of linking orbits to ice ages p.208
1976年、地球の公転軌道のわずかなゆらぎが、過去数百万年の大氷河時代の氷期サイクルにつながったことが実証された。この発見は気候科学に広く関係するもので、その詳細については現在も議論が盛んに行われている。
doi: 10.1038/540208a
生物医学:細胞のエネルギー工場を置き換える
Biomedicine: Replacing the cell's power plants p.210
ミトコンドリアDNAに変異が生じているヒト卵子の核DNAを、ドナーの卵子に移植する実験が成功した。これはミトコンドリア病の治療法実現の期待に一歩近づく成果である。
doi: 10.1038/nature20483
幹細胞:ナイーブ幹細胞を目指す努力
Stem cells: Aspiring to naivety p.211
ヒト体内のあらゆる種類の細胞を生じることができる幹細胞は、生物医学研究の主役の1つである。ヒト胚の分子レベルでの解析は、培養幹細胞をin vivoの幹細胞の信頼のおける模造品とするのに役立ちそうだ。
doi: 10.1038/nature20484
Reviews
量子情報:量子物理学における認証されたランダム性
Certified randomness in quantum physics p.213
Quantum technology enables new methods for generating of randomness with minimal assumptions, certified by the violation of a Bell inequality, which opens up new theoretical and experimental research directions and leads to new challenges.
doi: 10.1038/nature20119
生態学:花粉媒介者の保護および人類の幸福に対するその価値
Safeguarding pollinators and their values to human well-being p.220
Wild and managed pollinators are threatened by pressures such as environmental changes and pesticides, leading to risks for pollinator-dependent crop production, meaning more research and better policies are needed to safeguard pollinators and their services.
doi: 10.1038/nature20588
Articles
神経科学:ガンマ周波数の同調はアミロイドの蓄積を軽減してミクログリアを変化させる
Gamma frequency entrainment attenuates amyloid load and modifies microglia p.230
Mouse models of Alzheimer’s disease show reduced, behaviourally driven gamma oscillations before the onset of plaque formation or cognitive decline; driving neurons to oscillate at gamma frequency (40 Hz) reduces levels of amyloid-β peptides.
doi: 10.1038/nature20587
免疫学:S-2-ヒドロキシグルタル酸はCD8+ Tリンパ球の運命を調節する
S-2-hydroxyglutarate regulates CD8+ T-lymphocyte fate p.236
S-2-hydroxyglutarate produced by CD8+ T cells under hypoxic conditions affects locus-specific histone and DNA methylation patterns, which enhances T-cell proliferation, survival and recall responses.
doi: 10.1038/nature20165
分子生物学:ショウジョウバエでm6Aはニューロン機能と性決定を調節する
m6A modulates neuronal functions and sex determination in Drosophila p.242
One of the most abundant modifications found in messenger RNAs is N6-methyladenosine (m6A); here, this modification is shown to alter gene expression during sex determination and affect neuronal functions and behaviour in Drosophila via the m6A reader protein YT521-B.
doi: 10.1038/nature20568
Letters
宇宙論:赤方偏移2.1に位置する静穏な種族IIの大質量銀河
A massive, quiescent, population II galaxy at a redshift of 2.1 p.248
The ratio of magnesium to iron abundance is measured for a massive quiescent galaxy at a redshift of 2.1, corresponding to when the Universe was three billion years old.
doi: 10.1038/nature20570
気候科学:更新世においてグリーンランドには長期間ほとんど氷がなかった
Greenland was nearly ice-free for extended periods during the Pleistocene p.252
Measurements of cosmic-ray-produced 10Be and 26Al in a bedrock core from beneath the summit of the Greenland Ice Sheet show that Greenland was nearly ice-free for extended periods under Pleistocene climate forcing.
doi: 10.1038/nature20146
気候科学:過去750万年にわたって持続的で動的であった東グリーンランド氷床
A persistent and dynamic East Greenland Ice Sheet over the past 7.5 million years p.256
10Be and 26Al isotopic evidence in quartz sand from the seafloor shows that a dynamic East Greenland Ice Sheet has existed for the past 7.5 million years.
doi: 10.1038/nature20147
テクトニクス:東太平洋海膨における海底拡大事象のダイナミクス
Dynamics of a seafloor-spreading episode at the East Pacific Rise p.261
Seismic observations clarify the roles of magma pressure and tectonic stress in the development of seafloor spreading during the most recent eruption at the East Pacific Rise.
doi: 10.1038/nature20116
生物多様性:土地利用の強化は草原群集で多栄養段階の均質化を引き起こす
Land-use intensification causes multitrophic homogenization of grassland communities p.266
Analysis of a large grassland biodiversity dataset shows that increases in local land-use intensity cause biotic homogenization at landscape scale across microbial, plant and animal groups, both above- and belowground, that is largely independent of changes in local diversity.
doi: 10.1038/nature20575
生物医学:ミトコンドリアDNAに病原性変異を持つヒト卵母細胞でのミトコンドリア置換
Mitochondrial replacement in human oocytes carrying pathogenic mitochondrial DNA mutations p.270
Analysis of mitochondrial replacement therapy shows, even with efficient mutant mitochondrial DNA replacement and maintenance in embryonic stem cells, a gradual loss of donor mitochondrial DNA in some lines owing to a polymorphism in the D-loop, potentially causing preferential replication of specific mitochondrial DNA haplotypes.
doi: 10.1038/nature20592
幹細胞:常在幹細胞におけるPDGFRαイントロンのポリアデニル化は筋繊維症を軽減させる
Intronic polyadenylation of PDGFRα in resident stem cells attenuates muscle fibrosis p.276
Platelet-derived growth factor receptor α (PDGFRα) exhibits divergent effects in skeletal muscle. At physiological levels, signalling through this receptor promotes muscle development in growing embryos and angiogenesis in regenerating adult muscle. However, both increased PDGF ligand abundance and enhanced PDGFRα pathway activity cause pathological fibrosis. This excessive collagen deposition, which is seen in aged and diseased muscle, interferes with muscle function and limits the effectiveness of gene- and cell-based therapies for muscle disorders. Although compelling evidence exists for the role of PDGFRα in fibrosis, little is known about the cells through which this pathway acts. Here we show in mice that PDGFRα signalling regulates a population of muscle-resident fibro/adipogenic progenitors (FAPs) that play a supportive role in muscle regeneration but may also cause fibrosis when aberrantly regulated. We found that FAPs produce multiple transcriptional variants of Pdgfra with different polyadenylation sites, including an intronic variant that codes for a protein isoform containing a truncated kinase domain. This variant, upregulated during regeneration, acts as a decoy to inhibit PDGF signalling and to prevent FAP over-activation. Moreover, increasing the expression of this isoform limits fibrosis in vivo in mice, suggesting both biological relevance and therapeutic potential of modulating polyadenylation patterns in stem-cell populations.
doi: 10.1038/nature20160
微生物学:ミクロシンは炎症の起こっている腸管で腸内細菌科の細菌間に競争を引き起こす
Microcins mediate competition among Enterobacteriaceae in the inflamed gut p.280
Certain commensal enterobacteria secrete small proteins called microcins that suppress the growth of other bacteria in the inflamed gut, conferring an intra- and interspecies competitive advantage.
doi: 10.1038/nature20557
免疫学:SIV感染アカゲザルでのTLR7刺激を併用するAd26/MVA治療用ワクチン接種
Ad26/MVA therapeutic vaccination with TLR7 stimulation in SIV-infected rhesus monkeys p.284
The development of immunologic interventions that can target the viral reservoir in HIV-1-infected individuals is a major goal of HIV-1 research. However, little evidence exists that the viral reservoir can be sufficiently targeted to improve virologic control following discontinuation of antiretroviral therapy. Here we show that therapeutic vaccination with Ad26/MVA (recombinant adenovirus serotype 26 (Ad26) prime, modified vaccinia Ankara (MVA) boost) and stimulation of TLR7 (Toll-like receptor 7) improves virologic control and delays viral rebound following discontinuation of antiretroviral therapy in SIV-infected rhesus monkeys that began antiretroviral therapy during acute infection. Therapeutic vaccination with Ad26/MVA resulted in a marked increase in the magnitude and breadth of SIV-specific cellular immune responses in virologically suppressed, SIV-infected monkeys. TLR7 agonist administration led to innate immune stimulation and cellular immune activation. The combination of Ad26/MVA vaccination and TLR7 stimulation resulted in decreased levels of viral DNA in lymph nodes and peripheral blood, and improved virologic control and delayed viral rebound following discontinuation of antiretroviral therapy. The breadth of cellular immune responses correlated inversely with set point viral loads and correlated directly with time to viral rebound. These data demonstrate the potential of therapeutic vaccination combined with innate immune stimulation as a strategy aimed at a functional cure for HIV-1 infection.
doi: 10.1038/nature20583
微生物学:mavirusヴィロファージの宿主ゲノムへの組み込みと巨大ウイルスによる再活性化
Host genome integration and giant virus-induced reactivation of the virophage mavirus p.288
Endogenous viral elements found in a marine protozoan have a function in defence against infection by giant viruses.
doi: 10.1038/nature20593
タンパク質設計:設計されたタンパク質が誘導するナノケージを持つ細胞外小胞の形成
Designed proteins induce the formation of nanocage-containing extracellular vesicles p.292
Autonomously produced hybrid biological nanomaterials termed ‘enveloped protein nanocages’ incorporate features for membrane binding, self-assembly, and ESCRT recruitment for cellular release.
doi: 10.1038/nature20607
細胞生物学:2点接触型および複数点接触型の染色体コンホメーションの、染色体歩行を用いた捕捉
Capturing pairwise and multi-way chromosomal conformations using chromosomal walks p.296
A conformation capture sequencing method is developed to link multiple genomic loci into three-dimensional proximity chains called chromosomal walks (C-walks), adding to our understanding of how higher-order chromosomal structures participate in genome regulation.
doi: 10.1038/nature20158
分子生物学:m6A はショウジョウバエのロバストな性決定のためにSxl mRNA前駆体の選択的スプライシングを促進する
m6A potentiates Sxl alternative pre-mRNA splicing for robust Drosophila sex determination p.301
N6-methyladenosine (m6A) is the most common internal modification of eukaryotic messenger RNA (mRNA) and is decoded by YTH domain proteins. The mammalian mRNA m6A methylosome is a complex of nuclear proteins that includes METTL3 (methyltransferase-like 3), METTL14, WTAP (Wilms tumour 1-associated protein) and KIAA1429. Drosophila has corresponding homologues named Ime4 and KAR4 (Inducer of meiosis 4 and Karyogamy protein 4), and Female-lethal (2)d (Fl(2)d) and Virilizer (Vir). In Drosophila, fl(2)d and vir are required for sex-dependent regulation of alternative splicing of the sex determination factor Sex lethal (Sxl). However, the functions of m6A in introns in the regulation of alternative splicing remain uncertain. Here we show that m6A is absent in the mRNA of Drosophila lacking Ime4. In contrast to mouse and plant knockout models, Drosophila Ime4-null mutants remain viable, though flightless, and show a sex bias towards maleness. This is because m6A is required for female-specific alternative splicing of Sxl, which determines female physiognomy, but also translationally represses male-specific lethal 2 (msl-2) to prevent dosage compensation in females. We further show that the m6A reader protein YT521-B decodes m6A in the sex-specifically spliced intron of Sxl, as its absence phenocopies Ime4 mutants. Loss of m6A also affects alternative splicing of additional genes, predominantly in the 5′ untranslated region, and has global effects on the expression of metabolic genes. The requirement of m6A and its reader YT521-B for female-specific Sxl alternative splicing reveals that this hitherto enigmatic mRNA modification constitutes an ancient and specific mechanism to adjust levels of gene expression.
doi: 10.1038/nature20577