《Nature》目录要览：2009-08-20出版
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《Nature》目录要览：2009-08-20出版
封面故事：柏基斯页岩化石层发现100周年纪念
Misadventures in the Burgess Shale
古生物学的发展，在很大程度上要归功于100年前的这个月在加拿大不列颠哥伦比亚省
约霍国家公园中柏基斯页岩化石层的发现。关于距今5.05亿年前寒武纪海洋中多样化生
命的这一举世瞩目的化石记录也理所当然地出了名，并在Stephen J. Gould的《美妙生
命》一书中有所记述。在本期Nature的“Opinion”文章中，Desmond Collins回顾了
Charles Doolittle Walcott发现这些页岩的故事。由于人们当时所掌握的知识的局限
性，Walcott要解释他所发现的东西实际上是一个可怕的挑战。人们走了一些错误的线
路，在几十年的时间里，这些化石也几乎被完全遗忘，但Collins说，Walcott的成就完
全值得我们对其进行百年纪念，目前相关纪念活动正在进行当中。（Opinion
p.952）。请阅读Nicola Jones参加上周在加拿大班芙举行的“Walcott 2009”会议之
后所撰写的针对不同化石的博客文章，网址是：http://tinyurl.com/burgess100 。
内共生在细菌演化中所起作用（Bacterial origins）
Evidence for an early prokaryotic endosymbiosis
内共生（不同生命形式融合起来创造一个新的、更复杂的整体）被认为在复杂细胞的演
化中具有重要作用。细胞的不同部分——细胞核、线粒体等——是曾经独立的生物体的
残迹。但内共生是否在较简单的生物如细菌的演化中也曾扮演一个角色？这个问题通常
没有被人们所考虑，因为这些生物没有分成不同部分的内部结构。然而，很多成功的和
重要的细菌都有双层细胞膜，而且在本期Nature上的一篇“假说”文章中，James Lake
提出，这是两种不同细菌细胞类型之间的融合遗留下来的，这两种细菌细胞类型分别是
梭菌和放射菌。 （Hypothesis p. 967）
高谐波干涉测量法的应用（Attosecond sight）
High harmonic interferometry of multi-electron dynamics in molecules
伴随一个电子与其母分子离子在一个强激光场中的重组所出现的高强度谐波辐射，能让
我们有机会一瞥重组体系的结构和动态。现在，用CO2分子所做实验表明，高谐波干涉
测量法能够提取这种结构和动态信息：通过测量谐波辐射的位相和振幅来进行。所获得
的参与这一过程的多个分子轨道的“指纹”，可被用来解码产生这种“指纹”的阿秒级
的多电子动态，包括因离子化而发生的电子重排的动态。从该体系中发出的光含有运动
中的电子的图像，它们可被处理成一部影片。这些发现确立了高谐波干涉测量法是根据
重组电子的德布罗意波长来以“亚埃级”空间分辨率和根据重组事件的时间尺度来以阿
秒级时间分辨率确定多电子动态的一种有效方法。（Article p. 972; News & Views）
Atlastin在内质网形成中所起作用（Atlastin’s role in ER）
Homotypic fusion of ER membranes requires the dynamin-like GTPase Atlastin
内质网对包括膜的生物发生、囊泡运输和蛋白分泌在内的很多细胞功能都很关键，它是
一个由管状结构构成的互联的网络，遍及真核细胞。这一特定结构的维持机制尚不清
楚，尽管依赖于GTP水解的同型膜融合已知是内质网的生物发生和维持所必需的。现
在，用果蝇所进行的一项研究表明，被称为Atlastin的一种GTP酶（在遗传性痉挛性截
瘫中发生突变的人类Atlastin 1的一个同源分子）是同型膜融合所必需的，因而也是内
质网形成所必需的。（Article p. 978）
减小基因组重排风险的机制（Minimizing the genetic risk）
Specific pathways prevent duplication-mediated genome rearrangements
人类基因组含有无数种“有风险的”重复序列，它们易于造成基因组重排和不稳定，其
中有些还有可能引起癌症和其他疾病。细胞利用各种不同蛋白来确保这种不稳定性的发
生频率非常低。对酿酒酵母染色体V左臂所做的一项研究，确定了大量能够防止这种重
排的基因。令人吃惊的是，抑制由单版本序列或“有风险的”重复序列调控的重排有截
然不同的通道。（Article p. 984）
宇宙起源的随机引力波背景上限被设定（LIGO in the background）
An upper limit on the stochastic gravitational-wave background of
cosmological origin
广义相对论预测，所有物体都产生应可检测到的引力波（与电磁波类似），比如说质量
极大的物体如正在加速中的黑洞。这种波的存在已被间接推断出，但物理学上的一个重
要目标是对它们进行直接观测，这项工作将既能验证爱因斯坦的理论，又能导致宇宙学
新领域的问世。现在，来自“激光干涉仪引力波天文台”（ 英文简称为LIGO，它是寻
找引力波的一些探测装置之一）的早期结果，为进一步的引力波搜索工作提供了一个起
点，因为它们为来自宇宙起源的引力波的随机背景设定了一个上限。这些数据排除了具
有一个相对较大的状态方程参数的早期宇宙演化模型，也排除了具有相对较小弦张力的
宇宙（超）弦模型（一些弦理论模型支持这样的模型）。（Letter p990; News &
Views）
印度西北部地下水的消耗(India’s lost water)
Satellite-based estimates of groundwater depletion in India
水资源在世界很多地方都很珍贵，印度就是其中之一。间接证据表明，在印度西北地
区，地下水目前的消耗速度快于其自然补充速度，但根据基于地面的测量结果（这些测
量结果经常是分散的和不完整的）难以评估大尺度的消耗速度。来自美国国家航空航天
局“引力恢复和气候实验”（ GRACE）卫星的引力观测结果，与地表模型相结合，被用
来生成关于印度地下水存量变化的月度时间序列。此项分析显示，在2002年和2008年
间，印度西北部地下水消耗的严重程度逐渐增强。在印度西北部的拉贾斯坦邦、旁遮普
邦和哈里亚纳邦，地下水消耗的年平均速度为4厘米，相当于在这个时期地下水净损失
109立方公里。本文作者们认为，用于灌溉和其他人工用途的不可持续的地下水消耗是
造成这种情况的最可能的原因。（Letter p. 999; News）
地幔中电导率的变化模型（Hydrating the mantle）
Global electromagnetic induction constraints on transition-zone water
content variations
水在地球内部起根本性作用，影响地幔矿物质的熔化温度、地幔熔化形成地幔柱的趋
势、以及对流地幔的粘度。地幔矿物质的电导率受水含量的较大影响。Kelbert等人利
用长期地磁响应函数来推导一个关于地幔中电导率变化情况的全球尺度的三维模型。他
们的研究显示，地幔过渡区（深度在410公里-660公里之间）的变化为大约一个数量
级，其中在温度低的、地震波传播快的区域电导率高（那些地方的板块已经下潜）。这
一结果支持以下观点：过渡带中的水至少有一部分被冷的下潜板块带到了该区域。
（Letter p. 1003）
动物种群同步波动探秘（All together now）
Phase-locking and environmental fluctuations generate synchrony in a
predator–prey community
了解什么使种群发生同步波动很重要，因为同步对灭绝风险、食物链稳定性和影响一个
生态系统的其他因素都有明显效应。相似的捕食者-猎物循环中所涉及的相邻种群经常
发生同步振荡，David Vasseur 和Jeremy Fox利用理论及实验室缩微环境发现，当捕食
者存在时，猎物种群之间的扩散是造成这种相位锁定（相位同步）的原因。扩散是不同
生物（Vasseur 和 Fox所研究的动物是雪兔和加拿大猞猁）从一个分离的种群向另一个
转移的能力。由这项工作所获得的模型对于代表捕食者-猎物和宿主-病原体系统的参数
的大范围变化都是可靠的，说明它可能具有普遍适用性。（Letter p. 1007）
又一朝鲜族男子基因组完成测序（Then there were six）
A highly annotated whole-genome sequence of a Korean individual
研究人员利用一系列不同的基因组方法完成了对一个匿名朝鲜族男子基因组的测序。这
种组合测序方式使研究人员能够对序列和结构变化进行详细定性。世界上最先测序的四
个个人基因组分属三个不同族群：一个非洲约鲁巴人、两个来自欧洲西北地区的人
（Craig Venter 和 James Watson）和一个汉族人。这项新的工作，连同在其他刊物上
所报告的另一个朝鲜族人基因组序列，又将阿尔泰族群添加到了这个清单上。（Letter
p. 1011）
新的流感病毒得到定性（Pandemic virus characterized）
In vitro and in vivo characterization of new swine-origin H1N1 influenza
viruses
对起源于猪的H1N1流感病毒的一系列临床分离株所做的分析显示，在哺乳动物模型（小
鼠、雪貂和猕猴）中，与一种季节性的H1N1病毒类型相比，当前的流感病毒会造成更严
重的疾病。这些病毒还会感染猪，但不会引起临床症状。经过测试的所有抗病毒药物，
包括Tamiflu，在细胞培养中对该新病毒都是有效的，因而用这些药物作为防止流感疫
情的第一道防线的做法是正确的。（Letter p. 1021）
触发深水水稻中间节增长的基因（SNORKEL beats the monsoon）
The ethylene response factors SNORKEL1 and SNORKEL2 allow rice to adapt to
deep water
亚洲季风季节的洪涝灾害会对水稻作物造成广泛破坏。一些品种的水稻已通过形成使茎
秆迅速加长的能力而适应了这种环境压力。正常情况下，这种类型的水稻可长到约一米
高，但当发生洪涝时，其茎秆会发生迅速的、急剧的中间节增长，能长到几米高，其高
度由水位决定。Hattori等人识别出了触发深水水稻中间节增长的基因，它们分别是
SNORKEL 1 和 SNORKEL 2。这两个基因编码调控气态植物激素乙烯信号作用的转录因
子。将这些基因导入高产栽培品种中，有可能帮助易发生洪涝地区水稻增产。（Letter
p. 1026; News & Views）
----------------------
NEWS AND VIEWS
----------------------
Plant biology: Genetics of high-rise rice pp959-960
When subject to flooding, deepwater rice survives by shooting up in height.
Knowledge of the genetic context of this and other responses to inundation
will be a boon in enhancing rice productivity.
Laurentius A. C. J. Voesenek and Julia Bailey-Serres
doi:10.1038/460959a
http://www.nature.com/nature/journal/v460/n7258/full/460959a.html
Chemical physics: Electronic movies pp960-961
Strong laser fields can tear an electron away from a molecule, leaving a
hole in the electronic wavefunction that races through the molecule. The
ultrafast motion of such a hole has been traced at last.
Marc Vrakking
doi:10.1038/460960a
http://www.nature.com/nature/journal/v460/n7258/full/460960a.html
Neuroscience: Activity acts locally pp961-963
How does neuronal activity affect the development of neural circuits? Work
on the retina shows that blocking activity at the synapses between neurons
reduces local synapse assembly without affecting global cellular structure.
Jonathan B. Demb and Marla B. Feller
doi:10.1038/460961a
http://www.nature.com/nature/journal/v460/n7258/full/460961a.html
Planetary science: Archaeology of the asteroid belt pp963-964
The size of asteroids in the Solar System's main asteroid belt may help
constrain one of the least-understood aspects of planet formation - the
transition from pebble-sized dust balls to mountain-sized planetesimals.
John Chambers
doi:10.1038/460963a
http://www.nature.com/nature/journal/v460/n7258/full/460963a.html
Astrophysics: Gravity ripples chased pp964-965
Discovering gravitational waves would not only validate Einstein's theory
of gravitation but also reveal aspects of the Universe's earliest moments.
The hunt for these elusive ripples is now well under way.
Marc Kamionkowski
doi:10.1038/460964a
http://www.nature.com/nature/journal/v460/n7258/full/460964a.html
----------------------
HYPOTHESIS
----------------------
Evidence for an early prokaryotic endosymbiosis pp967-971
James A. Lake
doi:10.1038/nature08183
Abstract:
http://www.nature.com/nature/journal/v460/n7258/abs/nature08183.html
Article:
http://www.nature.com/nature/journal/v460/n7258/full/nature08183.html
----------------------
ARTICLES
----------------------
High harmonic interferometry of multi-electron dynamics in molecules
pp972-977
The high harmonic emission that accompanies the recombination of an
electron with its parent molecular ion in an intense laser field provides
a snapshot of the structure and dynamics of the recombining system.
Experiments on CO2 molecules now show how to extract information from
the properties of the emitted light about the underlying multi-electron
dynamics with sub-Angstrom spatial resolution and attosecond temporal
resolution
Olga Smirnova et al.
doi:10.1038/nature08253
Abstract:
http://www.nature.com/nature/journal/v460/n7258/abs/nature08253.html
Article:
http://www.nature.com/nature/journal/v460/n7258/full/nature08253.html
Homotypic fusion of ER membranes requires the dynamin-like GTPase Atlastin
pp978-983
The mechanism by which the tubular architecture of the endoplasmic reticulum
(ER) is maintained is unclear, although homotypic membrane fusion is known
to be required for ER biogenesis and maintenance and this is dependent on
GTP hydrolysis. Here it is demonstrated that loss of the GTPase Atlastin
in Drosophila causes ER fragmentation, whereas its overexpression induces
enlargement of ER profiles.
Genny Orso et al.
doi:10.1038/nature08280
Abstract:
http://www.nature.com/nature/journal/v460/n7258/abs/nature08280.html
Article:
http://www.nature.com/nature/journal/v460/n7258/full/nature08280.html
Specific pathways prevent duplication-mediated genome rearrangements
pp984-989
The human genome contains numerous types of repeated 'at risk' sequences
that can cause genomic rearrangements and instability. Various proteins
are used to ensure that this occurs very infrequently. Here, a comprehensive
analysis of the factors involved in suppressing gross chromosomal
rearrangements in Saccharomyces cerevisiae shows that there are distinct
pathways for suppressing rearrangements mediated by single copy sequences
versus repetitive 'at risk' sequences.
Christopher D. Putnam, Tikvah K. Hayes and Richard D. Kolodner
doi:10.1038/nature08217
Abstract:
http://www.nature.com/nature/journal/v460/n7258/abs/nature08217.html
Article:
http://www.nature.com/nature/journal/v460/n7258/full/nature08217.html
----------------------
LETTERS
----------------------
An upper limit on the stochastic gravitational-wave background of
cosmological
origin pp990-994
A stochastic background of gravitational waves is expected to arise from a
superposition of a large number of unresolved gravitational-wave sources and
should carry unique signatures from the earliest epochs of the Universe.
Limits on the amplitude of the stochastic gravitational-wave background are
now reported using the data from a two-year science run of the Laser
Interferometer Gravitational-wave Observatory. These limits rule out
certain models of early Universe evolution.
B. P. Abbott et al.
doi:10.1038/nature08278
Abstract:
http://www.nature.com/nature/journal/v460/n7258/abs/nature08278.html
Article:
http://www.nature.com/nature/journal/v460/n7258/full/nature08278.html
In situ observation of incompressible Mott-insulating domains in ultracold
atomic gases pp995-998
Ultracold atoms held in an optical lattice are an important system in which
to study quantum phase transitions. However, the presence of multiple
quantum
phases within a single sample complicates the interpretation of bulk
measurements. Here, a direct imaging method is reported that enables a
complete characterization of multiple phases in a strongly correlated
Bose gas.
Nathan Gemelke, Xibo Zhang, Chen-Lung Hung and Cheng Chin
doi:10.1038/nature08244
Abstract:
http://www.nature.com/nature/journal/v460/n7258/abs/nature08244.html
Article:
http://www.nature.com/nature/journal/v460/n7258/full/nature08244.html
Satellite-based estimates of groundwater depletion in India pp999-1002
Indirect evidence suggests that groundwater is being consumed faster than it
is naturally being replenished in northwest India, but there has been no
regional assessment of the rate of groundwater depletion. Terrestrial water
storage-change observations and simulated soil-water variations from a
modelling system are now used to show that groundwater is indeed being
depleted and that its use for irrigation and other anthropogenic uses is
likely to be the cause.
Matthew Rodell, Isabella Velicogna and James S. Famiglietti
doi:10.1038/nature08238
Abstract:
http://www.nature.com/nature/journal/v460/n7258/abs/nature08238.html
Article:
http://www.nature.com/nature/journal/v460/n7258/full/nature08238.html
Global electromagnetic induction constraints on transition-zone water
content
variations pp1003-1006
Electrical conductivity is highly sensitive to the presence of hydrogen in
mantle materials, an important measure as small amounts of water can
significantly affect the physical properties of mantle materials, with
profound implications for the dynamic and geochemical evolution of the
Earth. Here, long-period geomagnetic response functions are used to derive
a global-scale three-dimensional model of electrical conductivity variations
in the Earth's mantle.
Anna Kelbert, Adam Schultz and Gary Egbert
doi:10.1038/nature08257
Abstract:
http://www.nature.com/nature/journal/v460/n7258/abs/nature08257.html
Article:
http://www.nature.com/nature/journal/v460/n7258/full/nature08257.html
Phase-locking and environmental fluctuations generate synchrony in a
predator--prey community pp1007-1010
Adjacent populations that are involved in similar predator-prey cycles often
oscillate in synchrony. Here, a general stochastic model of predator-prey
spatial dynamics is developed to predict the outcome of a laboratory
microcosm
experiment testing for interactions among synchronizing factors; both model
and data indicate that synchrony depends on cyclic dynamics generated by the
predator.
David A. Vasseur and Jeremy W. Fox
doi:10.1038/nature08208
Abstract:
http://www.nature.com/nature/journal/v460/n7258/abs/nature08208.html
Article:
http://www.nature.com/nature/journal/v460/n7258/full/nature08208.html
A highly annotated whole-genome sequence of a Korean individual pp1011-1015
Human genome sequences have so far been reported for individuals with
ancestry
in three distinct geographical regions: a Yoruba African, two individuals of
northwest European origin, and a person from China. Here, using a
combination
of methods, a highly annotated, whole-genome sequence is provided for a
Korean male.
Jong-Il Kim et al.
doi:10.1038/nature08211
Abstract:
http://www.nature.com/nature/journal/v460/n7258/abs/nature08211.html
Article:
http://www.nature.com/nature/journal/v460/n7258/full/nature08211.html
Neurotransmission selectively regulates synapse formation in parallel
circuits
in vivo pp1016-1020
Activity is thought to help shape connectivity within neural circuits, with
differences often leading to the elimination of less active connections. In
order to imbalance neurotransmission from different sets of inputs in vivo,
a
subpopulation of bipolar cells was inactivated during development. The
results
reveal an unexpected and remarkably selective role for activity in circuit
development, regulating synapse formation but not elimination.
Daniel Kerschensteiner et al.
doi:10.1038/nature08236
Abstract:
http://www.nature.com/nature/journal/v460/n7258/abs/nature08236.html
Article:
http://www.nature.com/nature/journal/v460/n7258/full/nature08236.html
In vitro and in vivo characterization of new swine-origin H1N1 influenza
viruses
pp1021-1025
On 11 June 2009 the World Health Organization declared that the infections
caused by a new strain of influenza A virus closely related to swine viruses
had reached pandemic levels. Here, one of the first US isolates of the new
swine-origin H1N1 influenza virus (S-OIV) is characterized, as well as
several
other S-OIV isolates, both in vitro and in vivo.
Yasushi Itoh et al.
doi:10.1038/nature08260
Abstract:
http://www.nature.com/nature/journal/v460/n7258/abs/nature08260.html
Article:
http://www.nature.com/nature/journal/v460/n7258/full/nature08260.html
The ethylene response factors SNORKEL1 and SNORKEL2 allow rice to adapt to
deep water pp1026-1030
In Asia, flooding during the monsoon season can result in widespread
devastation
of rice crops. Deepwater rice has evolved and adapted to flooding by
acquiring
the ability to significantly elongate its internodes. The molecular
mechanism
of this deepwater response is now identified as being dependent on the genes
SNORKEL1 and SNORKEL2, which trigger deepwater response by encoding ethylene
response factors involved in ethylene signalling.
Yoko Hattori et al.
doi:10.1038/nature08258
Abstract:
http://www.nature.com/nature/journal/v460/n7258/abs/nature08258.html
Article:
http://www.nature.com/nature/journal/v460/n7258/full/nature08258.html
Characterization of two classes of small molecule inhibitors of Arp2/3
complex
pp1031-1034
The actin cytoskeleton plays a critical role in cell biological processes
such
as cell adhesion, migration and endocytosis. Polymerization of actin
filaments
directed by the actin-related protein (Arp)2/3 complex supports many types
of
cellular movement. Two classes of small molecules that bind to different
sites
on the Arp2/3 complex and inhibit its ability to nucleate actin filaments
are
now described; these inhibitors provide a powerful approach for studying the
Arp2/3 complex in living cells.
B. J. Nolen et al.
doi:10.1038/nature08231
Abstract:
http://www.nature.com/nature/journal/v460/n7258/abs/nature08231.html
Article:
http://www.nature.com/nature/journal/v460/n7258/full/nature08231.html
XIAP discriminates between type I and type II FAS-induced
apoptosis pp1035-1039
The 'death receptor' FAS regulates apoptosis of unwanted or dangerous cells,
functioning as a guardian against autoimmunity and cancer development.
Distinct
cell types differ in the mechanisms by which FAS triggers apoptosis: in type
I
cells, FAS-induced activation of caspase-8 suffices for cell killing,
whereas
in type II cells there must be caspase cascade amplification. Here it is
shown
that the inhibitor of apoptosis XIAP is the critical factor determining this
- without it, a type II cell dies in the same way as a type I cell.
Philipp J. Jost et al.
doi:10.1038/nature08229
Abstract:
http://www.nature.com/nature/journal/v460/n7258/abs/nature08229.html
Article:
http://www.nature.com/nature/journal/v460/n7258/full/nature08229.html
Structure of a prokaryotic virtual proton pump at 3.2[thinsp]A resolution
pp1040-1043
Little is known about the structure of the APC superfamily of membrane
proteins,
which transport amino acids, polyamines and organic cations in a multitude
of
biological roles. Here, the crystal structure of a member of this family,
AdiC,
is described at 3.2 A resolution.
Yiling Fang et al.
doi:10.1038/nature08201
Abstract:
http://www.nature.com/nature/journal/v460/n7258/abs/nature08201.html
Article:
http://www.nature.com/nature/journal/v460/n7258/full/nature08201.html
----------------------
FUTURES
----------------------
The Piltdown angel p1050
Dig for victory.
John P. Boyd
doi:10.1038/4601050a
http://www.nature.com/nature/journal/v460/n7258/full/4601050a.html
Misadventures in the Burgess Shale
古生物学的发展，在很大程度上要归功于100年前的这个月在加拿大不列颠哥伦比亚省
约霍国家公园中柏基斯页岩化石层的发现。关于距今5.05亿年前寒武纪海洋中多样化生
命的这一举世瞩目的化石记录也理所当然地出了名，并在Stephen J. Gould的《美妙生
命》一书中有所记述。在本期Nature的“Opinion”文章中，Desmond Collins回顾了
Charles Doolittle Walcott发现这些页岩的故事。由于人们当时所掌握的知识的局限
性，Walcott要解释他所发现的东西实际上是一个可怕的挑战。人们走了一些错误的线
路，在几十年的时间里，这些化石也几乎被完全遗忘，但Collins说，Walcott的成就完
全值得我们对其进行百年纪念，目前相关纪念活动正在进行当中。（Opinion
p.952）。请阅读Nicola Jones参加上周在加拿大班芙举行的“Walcott 2009”会议之
后所撰写的针对不同化石的博客文章，网址是：http://tinyurl.com/burgess100 。
内共生在细菌演化中所起作用（Bacterial origins）
Evidence for an early prokaryotic endosymbiosis
内共生（不同生命形式融合起来创造一个新的、更复杂的整体）被认为在复杂细胞的演
化中具有重要作用。细胞的不同部分——细胞核、线粒体等——是曾经独立的生物体的
残迹。但内共生是否在较简单的生物如细菌的演化中也曾扮演一个角色？这个问题通常
没有被人们所考虑，因为这些生物没有分成不同部分的内部结构。然而，很多成功的和
重要的细菌都有双层细胞膜，而且在本期Nature上的一篇“假说”文章中，James Lake
提出，这是两种不同细菌细胞类型之间的融合遗留下来的，这两种细菌细胞类型分别是
梭菌和放射菌。 （Hypothesis p. 967）
高谐波干涉测量法的应用（Attosecond sight）
High harmonic interferometry of multi-electron dynamics in molecules
伴随一个电子与其母分子离子在一个强激光场中的重组所出现的高强度谐波辐射，能让
我们有机会一瞥重组体系的结构和动态。现在，用CO2分子所做实验表明，高谐波干涉
测量法能够提取这种结构和动态信息：通过测量谐波辐射的位相和振幅来进行。所获得
的参与这一过程的多个分子轨道的“指纹”，可被用来解码产生这种“指纹”的阿秒级
的多电子动态，包括因离子化而发生的电子重排的动态。从该体系中发出的光含有运动
中的电子的图像，它们可被处理成一部影片。这些发现确立了高谐波干涉测量法是根据
重组电子的德布罗意波长来以“亚埃级”空间分辨率和根据重组事件的时间尺度来以阿
秒级时间分辨率确定多电子动态的一种有效方法。（Article p. 972; News & Views）
Atlastin在内质网形成中所起作用（Atlastin’s role in ER）
Homotypic fusion of ER membranes requires the dynamin-like GTPase Atlastin
内质网对包括膜的生物发生、囊泡运输和蛋白分泌在内的很多细胞功能都很关键，它是
一个由管状结构构成的互联的网络，遍及真核细胞。这一特定结构的维持机制尚不清
楚，尽管依赖于GTP水解的同型膜融合已知是内质网的生物发生和维持所必需的。现
在，用果蝇所进行的一项研究表明，被称为Atlastin的一种GTP酶（在遗传性痉挛性截
瘫中发生突变的人类Atlastin 1的一个同源分子）是同型膜融合所必需的，因而也是内
质网形成所必需的。（Article p. 978）
减小基因组重排风险的机制（Minimizing the genetic risk）
Specific pathways prevent duplication-mediated genome rearrangements
人类基因组含有无数种“有风险的”重复序列，它们易于造成基因组重排和不稳定，其
中有些还有可能引起癌症和其他疾病。细胞利用各种不同蛋白来确保这种不稳定性的发
生频率非常低。对酿酒酵母染色体V左臂所做的一项研究，确定了大量能够防止这种重
排的基因。令人吃惊的是，抑制由单版本序列或“有风险的”重复序列调控的重排有截
然不同的通道。（Article p. 984）
宇宙起源的随机引力波背景上限被设定（LIGO in the background）
An upper limit on the stochastic gravitational-wave background of
cosmological origin
广义相对论预测，所有物体都产生应可检测到的引力波（与电磁波类似），比如说质量
极大的物体如正在加速中的黑洞。这种波的存在已被间接推断出，但物理学上的一个重
要目标是对它们进行直接观测，这项工作将既能验证爱因斯坦的理论，又能导致宇宙学
新领域的问世。现在，来自“激光干涉仪引力波天文台”（ 英文简称为LIGO，它是寻
找引力波的一些探测装置之一）的早期结果，为进一步的引力波搜索工作提供了一个起
点，因为它们为来自宇宙起源的引力波的随机背景设定了一个上限。这些数据排除了具
有一个相对较大的状态方程参数的早期宇宙演化模型，也排除了具有相对较小弦张力的
宇宙（超）弦模型（一些弦理论模型支持这样的模型）。（Letter p990; News &
Views）
印度西北部地下水的消耗(India’s lost water)
Satellite-based estimates of groundwater depletion in India
水资源在世界很多地方都很珍贵，印度就是其中之一。间接证据表明，在印度西北地
区，地下水目前的消耗速度快于其自然补充速度，但根据基于地面的测量结果（这些测
量结果经常是分散的和不完整的）难以评估大尺度的消耗速度。来自美国国家航空航天
局“引力恢复和气候实验”（ GRACE）卫星的引力观测结果，与地表模型相结合，被用
来生成关于印度地下水存量变化的月度时间序列。此项分析显示，在2002年和2008年
间，印度西北部地下水消耗的严重程度逐渐增强。在印度西北部的拉贾斯坦邦、旁遮普
邦和哈里亚纳邦，地下水消耗的年平均速度为4厘米，相当于在这个时期地下水净损失
109立方公里。本文作者们认为，用于灌溉和其他人工用途的不可持续的地下水消耗是
造成这种情况的最可能的原因。（Letter p. 999; News）
地幔中电导率的变化模型（Hydrating the mantle）
Global electromagnetic induction constraints on transition-zone water
content variations
水在地球内部起根本性作用，影响地幔矿物质的熔化温度、地幔熔化形成地幔柱的趋
势、以及对流地幔的粘度。地幔矿物质的电导率受水含量的较大影响。Kelbert等人利
用长期地磁响应函数来推导一个关于地幔中电导率变化情况的全球尺度的三维模型。他
们的研究显示，地幔过渡区（深度在410公里-660公里之间）的变化为大约一个数量
级，其中在温度低的、地震波传播快的区域电导率高（那些地方的板块已经下潜）。这
一结果支持以下观点：过渡带中的水至少有一部分被冷的下潜板块带到了该区域。
（Letter p. 1003）
动物种群同步波动探秘（All together now）
Phase-locking and environmental fluctuations generate synchrony in a
predator–prey community
了解什么使种群发生同步波动很重要，因为同步对灭绝风险、食物链稳定性和影响一个
生态系统的其他因素都有明显效应。相似的捕食者-猎物循环中所涉及的相邻种群经常
发生同步振荡，David Vasseur 和Jeremy Fox利用理论及实验室缩微环境发现，当捕食
者存在时，猎物种群之间的扩散是造成这种相位锁定（相位同步）的原因。扩散是不同
生物（Vasseur 和 Fox所研究的动物是雪兔和加拿大猞猁）从一个分离的种群向另一个
转移的能力。由这项工作所获得的模型对于代表捕食者-猎物和宿主-病原体系统的参数
的大范围变化都是可靠的，说明它可能具有普遍适用性。（Letter p. 1007）
又一朝鲜族男子基因组完成测序（Then there were six）
A highly annotated whole-genome sequence of a Korean individual
研究人员利用一系列不同的基因组方法完成了对一个匿名朝鲜族男子基因组的测序。这
种组合测序方式使研究人员能够对序列和结构变化进行详细定性。世界上最先测序的四
个个人基因组分属三个不同族群：一个非洲约鲁巴人、两个来自欧洲西北地区的人
（Craig Venter 和 James Watson）和一个汉族人。这项新的工作，连同在其他刊物上
所报告的另一个朝鲜族人基因组序列，又将阿尔泰族群添加到了这个清单上。（Letter
p. 1011）
新的流感病毒得到定性（Pandemic virus characterized）
In vitro and in vivo characterization of new swine-origin H1N1 influenza
viruses
对起源于猪的H1N1流感病毒的一系列临床分离株所做的分析显示，在哺乳动物模型（小
鼠、雪貂和猕猴）中，与一种季节性的H1N1病毒类型相比，当前的流感病毒会造成更严
重的疾病。这些病毒还会感染猪，但不会引起临床症状。经过测试的所有抗病毒药物，
包括Tamiflu，在细胞培养中对该新病毒都是有效的，因而用这些药物作为防止流感疫
情的第一道防线的做法是正确的。（Letter p. 1021）
触发深水水稻中间节增长的基因（SNORKEL beats the monsoon）
The ethylene response factors SNORKEL1 and SNORKEL2 allow rice to adapt to
deep water
亚洲季风季节的洪涝灾害会对水稻作物造成广泛破坏。一些品种的水稻已通过形成使茎
秆迅速加长的能力而适应了这种环境压力。正常情况下，这种类型的水稻可长到约一米
高，但当发生洪涝时，其茎秆会发生迅速的、急剧的中间节增长，能长到几米高，其高
度由水位决定。Hattori等人识别出了触发深水水稻中间节增长的基因，它们分别是
SNORKEL 1 和 SNORKEL 2。这两个基因编码调控气态植物激素乙烯信号作用的转录因
子。将这些基因导入高产栽培品种中，有可能帮助易发生洪涝地区水稻增产。（Letter
p. 1026; News & Views）
----------------------
NEWS AND VIEWS
----------------------
Plant biology: Genetics of high-rise rice pp959-960
When subject to flooding, deepwater rice survives by shooting up in height.
Knowledge of the genetic context of this and other responses to inundation
will be a boon in enhancing rice productivity.
Laurentius A. C. J. Voesenek and Julia Bailey-Serres
doi:10.1038/460959a
http://www.nature.com/nature/journal/v460/n7258/full/460959a.html
Chemical physics: Electronic movies pp960-961
Strong laser fields can tear an electron away from a molecule, leaving a
hole in the electronic wavefunction that races through the molecule. The
ultrafast motion of such a hole has been traced at last.
Marc Vrakking
doi:10.1038/460960a
http://www.nature.com/nature/journal/v460/n7258/full/460960a.html
Neuroscience: Activity acts locally pp961-963
How does neuronal activity affect the development of neural circuits? Work
on the retina shows that blocking activity at the synapses between neurons
reduces local synapse assembly without affecting global cellular structure.
Jonathan B. Demb and Marla B. Feller
doi:10.1038/460961a
http://www.nature.com/nature/journal/v460/n7258/full/460961a.html
Planetary science: Archaeology of the asteroid belt pp963-964
The size of asteroids in the Solar System's main asteroid belt may help
constrain one of the least-understood aspects of planet formation - the
transition from pebble-sized dust balls to mountain-sized planetesimals.
John Chambers
doi:10.1038/460963a
http://www.nature.com/nature/journal/v460/n7258/full/460963a.html
Astrophysics: Gravity ripples chased pp964-965
Discovering gravitational waves would not only validate Einstein's theory
of gravitation but also reveal aspects of the Universe's earliest moments.
The hunt for these elusive ripples is now well under way.
Marc Kamionkowski
doi:10.1038/460964a
http://www.nature.com/nature/journal/v460/n7258/full/460964a.html
----------------------
HYPOTHESIS
----------------------
Evidence for an early prokaryotic endosymbiosis pp967-971
James A. Lake
doi:10.1038/nature08183
Abstract:
http://www.nature.com/nature/journal/v460/n7258/abs/nature08183.html
Article:
http://www.nature.com/nature/journal/v460/n7258/full/nature08183.html
----------------------
ARTICLES
----------------------
High harmonic interferometry of multi-electron dynamics in molecules
pp972-977
The high harmonic emission that accompanies the recombination of an
electron with its parent molecular ion in an intense laser field provides
a snapshot of the structure and dynamics of the recombining system.
Experiments on CO2 molecules now show how to extract information from
the properties of the emitted light about the underlying multi-electron
dynamics with sub-Angstrom spatial resolution and attosecond temporal
resolution
Olga Smirnova et al.
doi:10.1038/nature08253
Abstract:
http://www.nature.com/nature/journal/v460/n7258/abs/nature08253.html
Article:
http://www.nature.com/nature/journal/v460/n7258/full/nature08253.html
Homotypic fusion of ER membranes requires the dynamin-like GTPase Atlastin
pp978-983
The mechanism by which the tubular architecture of the endoplasmic reticulum
(ER) is maintained is unclear, although homotypic membrane fusion is known
to be required for ER biogenesis and maintenance and this is dependent on
GTP hydrolysis. Here it is demonstrated that loss of the GTPase Atlastin
in Drosophila causes ER fragmentation, whereas its overexpression induces
enlargement of ER profiles.
Genny Orso et al.
doi:10.1038/nature08280
Abstract:
http://www.nature.com/nature/journal/v460/n7258/abs/nature08280.html
Article:
http://www.nature.com/nature/journal/v460/n7258/full/nature08280.html
Specific pathways prevent duplication-mediated genome rearrangements
pp984-989
The human genome contains numerous types of repeated 'at risk' sequences
that can cause genomic rearrangements and instability. Various proteins
are used to ensure that this occurs very infrequently. Here, a comprehensive
analysis of the factors involved in suppressing gross chromosomal
rearrangements in Saccharomyces cerevisiae shows that there are distinct
pathways for suppressing rearrangements mediated by single copy sequences
versus repetitive 'at risk' sequences.
Christopher D. Putnam, Tikvah K. Hayes and Richard D. Kolodner
doi:10.1038/nature08217
Abstract:
http://www.nature.com/nature/journal/v460/n7258/abs/nature08217.html
Article:
http://www.nature.com/nature/journal/v460/n7258/full/nature08217.html
----------------------
LETTERS
----------------------
An upper limit on the stochastic gravitational-wave background of
cosmological
origin pp990-994
A stochastic background of gravitational waves is expected to arise from a
superposition of a large number of unresolved gravitational-wave sources and
should carry unique signatures from the earliest epochs of the Universe.
Limits on the amplitude of the stochastic gravitational-wave background are
now reported using the data from a two-year science run of the Laser
Interferometer Gravitational-wave Observatory. These limits rule out
certain models of early Universe evolution.
B. P. Abbott et al.
doi:10.1038/nature08278
Abstract:
http://www.nature.com/nature/journal/v460/n7258/abs/nature08278.html
Article:
http://www.nature.com/nature/journal/v460/n7258/full/nature08278.html
In situ observation of incompressible Mott-insulating domains in ultracold
atomic gases pp995-998
Ultracold atoms held in an optical lattice are an important system in which
to study quantum phase transitions. However, the presence of multiple
quantum
phases within a single sample complicates the interpretation of bulk
measurements. Here, a direct imaging method is reported that enables a
complete characterization of multiple phases in a strongly correlated
Bose gas.
Nathan Gemelke, Xibo Zhang, Chen-Lung Hung and Cheng Chin
doi:10.1038/nature08244
Abstract:
http://www.nature.com/nature/journal/v460/n7258/abs/nature08244.html
Article:
http://www.nature.com/nature/journal/v460/n7258/full/nature08244.html
Satellite-based estimates of groundwater depletion in India pp999-1002
Indirect evidence suggests that groundwater is being consumed faster than it
is naturally being replenished in northwest India, but there has been no
regional assessment of the rate of groundwater depletion. Terrestrial water
storage-change observations and simulated soil-water variations from a
modelling system are now used to show that groundwater is indeed being
depleted and that its use for irrigation and other anthropogenic uses is
likely to be the cause.
Matthew Rodell, Isabella Velicogna and James S. Famiglietti
doi:10.1038/nature08238
Abstract:
http://www.nature.com/nature/journal/v460/n7258/abs/nature08238.html
Article:
http://www.nature.com/nature/journal/v460/n7258/full/nature08238.html
Global electromagnetic induction constraints on transition-zone water
content
variations pp1003-1006
Electrical conductivity is highly sensitive to the presence of hydrogen in
mantle materials, an important measure as small amounts of water can
significantly affect the physical properties of mantle materials, with
profound implications for the dynamic and geochemical evolution of the
Earth. Here, long-period geomagnetic response functions are used to derive
a global-scale three-dimensional model of electrical conductivity variations
in the Earth's mantle.
Anna Kelbert, Adam Schultz and Gary Egbert
doi:10.1038/nature08257
Abstract:
http://www.nature.com/nature/journal/v460/n7258/abs/nature08257.html
Article:
http://www.nature.com/nature/journal/v460/n7258/full/nature08257.html
Phase-locking and environmental fluctuations generate synchrony in a
predator--prey community pp1007-1010
Adjacent populations that are involved in similar predator-prey cycles often
oscillate in synchrony. Here, a general stochastic model of predator-prey
spatial dynamics is developed to predict the outcome of a laboratory
microcosm
experiment testing for interactions among synchronizing factors; both model
and data indicate that synchrony depends on cyclic dynamics generated by the
predator.
David A. Vasseur and Jeremy W. Fox
doi:10.1038/nature08208
Abstract:
http://www.nature.com/nature/journal/v460/n7258/abs/nature08208.html
Article:
http://www.nature.com/nature/journal/v460/n7258/full/nature08208.html
A highly annotated whole-genome sequence of a Korean individual pp1011-1015
Human genome sequences have so far been reported for individuals with
ancestry
in three distinct geographical regions: a Yoruba African, two individuals of
northwest European origin, and a person from China. Here, using a
combination
of methods, a highly annotated, whole-genome sequence is provided for a
Korean male.
Jong-Il Kim et al.
doi:10.1038/nature08211
Abstract:
http://www.nature.com/nature/journal/v460/n7258/abs/nature08211.html
Article:
http://www.nature.com/nature/journal/v460/n7258/full/nature08211.html
Neurotransmission selectively regulates synapse formation in parallel
circuits
in vivo pp1016-1020
Activity is thought to help shape connectivity within neural circuits, with
differences often leading to the elimination of less active connections. In
order to imbalance neurotransmission from different sets of inputs in vivo,
a
subpopulation of bipolar cells was inactivated during development. The
results
reveal an unexpected and remarkably selective role for activity in circuit
development, regulating synapse formation but not elimination.
Daniel Kerschensteiner et al.
doi:10.1038/nature08236
Abstract:
http://www.nature.com/nature/journal/v460/n7258/abs/nature08236.html
Article:
http://www.nature.com/nature/journal/v460/n7258/full/nature08236.html
In vitro and in vivo characterization of new swine-origin H1N1 influenza
viruses
pp1021-1025
On 11 June 2009 the World Health Organization declared that the infections
caused by a new strain of influenza A virus closely related to swine viruses
had reached pandemic levels. Here, one of the first US isolates of the new
swine-origin H1N1 influenza virus (S-OIV) is characterized, as well as
several
other S-OIV isolates, both in vitro and in vivo.
Yasushi Itoh et al.
doi:10.1038/nature08260
Abstract:
http://www.nature.com/nature/journal/v460/n7258/abs/nature08260.html
Article:
http://www.nature.com/nature/journal/v460/n7258/full/nature08260.html
The ethylene response factors SNORKEL1 and SNORKEL2 allow rice to adapt to
deep water pp1026-1030
In Asia, flooding during the monsoon season can result in widespread
devastation
of rice crops. Deepwater rice has evolved and adapted to flooding by
acquiring
the ability to significantly elongate its internodes. The molecular
mechanism
of this deepwater response is now identified as being dependent on the genes
SNORKEL1 and SNORKEL2, which trigger deepwater response by encoding ethylene
response factors involved in ethylene signalling.
Yoko Hattori et al.
doi:10.1038/nature08258
Abstract:
http://www.nature.com/nature/journal/v460/n7258/abs/nature08258.html
Article:
http://www.nature.com/nature/journal/v460/n7258/full/nature08258.html
Characterization of two classes of small molecule inhibitors of Arp2/3
complex
pp1031-1034
The actin cytoskeleton plays a critical role in cell biological processes
such
as cell adhesion, migration and endocytosis. Polymerization of actin
filaments
directed by the actin-related protein (Arp)2/3 complex supports many types
of
cellular movement. Two classes of small molecules that bind to different
sites
on the Arp2/3 complex and inhibit its ability to nucleate actin filaments
are
now described; these inhibitors provide a powerful approach for studying the
Arp2/3 complex in living cells.
B. J. Nolen et al.
doi:10.1038/nature08231
Abstract:
http://www.nature.com/nature/journal/v460/n7258/abs/nature08231.html
Article:
http://www.nature.com/nature/journal/v460/n7258/full/nature08231.html
XIAP discriminates between type I and type II FAS-induced
apoptosis pp1035-1039
The 'death receptor' FAS regulates apoptosis of unwanted or dangerous cells,
functioning as a guardian against autoimmunity and cancer development.
Distinct
cell types differ in the mechanisms by which FAS triggers apoptosis: in type
I
cells, FAS-induced activation of caspase-8 suffices for cell killing,
whereas
in type II cells there must be caspase cascade amplification. Here it is
shown
that the inhibitor of apoptosis XIAP is the critical factor determining this
- without it, a type II cell dies in the same way as a type I cell.
Philipp J. Jost et al.
doi:10.1038/nature08229
Abstract:
http://www.nature.com/nature/journal/v460/n7258/abs/nature08229.html
Article:
http://www.nature.com/nature/journal/v460/n7258/full/nature08229.html
Structure of a prokaryotic virtual proton pump at 3.2[thinsp]A resolution
pp1040-1043
Little is known about the structure of the APC superfamily of membrane
proteins,
which transport amino acids, polyamines and organic cations in a multitude
of
biological roles. Here, the crystal structure of a member of this family,
AdiC,
is described at 3.2 A resolution.
Yiling Fang et al.
doi:10.1038/nature08201
Abstract:
http://www.nature.com/nature/journal/v460/n7258/abs/nature08201.html
Article:
http://www.nature.com/nature/journal/v460/n7258/full/nature08201.html
----------------------
FUTURES
----------------------
The Piltdown angel p1050
Dig for victory.
John P. Boyd
doi:10.1038/4601050a
http://www.nature.com/nature/journal/v460/n7258/full/4601050a.html
| 《Nature》目录要览 — 2011-04-28出版 |
| 《Nature》目录要览：2011-01-20出版 |
| 《Nature》目录要览：2010-12-23出版 |
| 《Nature》目录要览：2010-12-16出版 |
| 《Nature》目录要览：2010-12-09出版 |
| 《Nature》目录要览：2010-12-02出版 |
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