《Nature》目录要览：2009年6月18日出版
时间：2009-06-19 阅读： 我要评论:
《Nature》目录要览：2009年6月18日出版
封面故事：应对H1N1猪流感病毒的能力与潜力
Emergence and pandemic potential of swine-origin H1N1 influenza virus
随着H1N1猪流感病毒疫情的爆发目前在世界卫生组织分类系统上被置于5级预警（6级则表示这种疫情的大范围流行已经发生），Gabriele Neumann、Takeshi Noda和Yoshihiro Kawaoka对关于H1N1病毒的出现及流行潜力的现有知识进行了盘点，并将以前传播的流感病毒毒株与“猪流感”毒株的抗原及病理性质进行了对比。他们得出的结论是，国际社会对于应对该疾病的大范围流行并没有做好准备，所储备的抗病毒药物并不充足，而且疫苗的生产也比较缓慢。关于我们今后是否能够准备得更好一些，他们的结论是，虽然我们已经了解了很多，但对于病毒跨物种传播、重组及人与人的传播等，我们还需要了解更多。本期封面图片是H1N1病毒的一个扫描电子显微照片（A/California/04/09），是在其从一个被病毒感染的细胞出现时拍到的。H1N1病毒颗粒大部分是细丝状，而不是球形，可以看到它覆盖在细胞表面上。（Review p. 931）
恐龙爪向翅膀演化的证据（A dinosaur in the hand）
A Jurassic ceratosaur from China helps clarify avian digital homologies
关于恐龙今天仍旧和我们在一起（如鸟类）的观点现已被普遍接受。但还有一个棘手的问题：鸟的前爪（现已退化、嵌入在翅膀中）被认为是从一个先祖的五指爪的第二、第三和第四指演化而来，而与鸟类亲缘关系最近的已灭绝物种（即兽脚类恐龙）的三指爪似乎是从第一、第二和第三指演化而来；一种爪何以变成了另一种？随着在中国西部准噶尔盆地侏罗纪地层中一个小型、原始兽脚类食草恐龙化石的发现，在恐龙研究方面成果颇丰的徐星及其同事可能已经解决了这一问题。这一生物生活在距今大约1.55亿年前，除了有发育较为充分的第二、第三和第四指外，还有第一指的一个残迹。这一原始恐龙的腕骨更像与二、三和四指相关的腕骨，但指骨本身更像一、二和三指。这表明，恐龙爪向翅膀的演化涉及腕和指所发生的复杂发育变化，而且这一新发现的恐龙让我们有机会一瞥当时正在发生的这种变化。（Article p. 940）
抗疟疾药物的新目标（Antimalaria target）
A newly discovered protein export machine in malaria parasites
在红细胞的细胞内感染过程中，疟原虫寄生在液泡中，并从那里将很多蛋白输出到宿主细胞中。这些蛋白的分泌在镰刀形疟原虫的感染力和生存力方面扮演一个重要角色。现在，这一过程中所涉及的蛋白输出机构已被确定。该机构被称为PTEX（它表示镰刀形疟原虫的Translocon of Exported蛋白），它是一个存在于液泡膜中的以ATP为动力的复合物，可能为抗疟疾药物提供一个新目标。（Article p. 945; News & Views）
李斯特菌从腐生菌转化为致病菌的奥秘（Listeria’s double life）
The Listeria transcriptional landscape from saprophytism to virulence
单核增生李斯特菌（Listeria monocytogenes）是一种常见的土壤细菌，在土壤中它是一种腐生菌，以死亡的和正在腐烂的有机物为食。它也是某些食物（主要是鲜奶产品）中的一种污染物，能引起严重食物中毒。关于在一系列不同生长条件下单核增生李斯特菌转录组（细胞中的全部mRNA转录体）的一项新的研究，搞清了从腐生到致病生活方式的这种转变的性质。该研究的数据显示了一个转录程序，其复杂程度出乎意料，它涉及50个非编码RNA，同时还有一系列新的调控RNA，包括几个长反义RNA。在感染过程中，李斯特菌通过协调的全组转录变化成功重塑其转录程序，其中某些非编码RNA优先在小肠或血液中生长的细胞中表达。（Article p. 950）
“木卫一”近于热平衡（Io’s tidal volcanoes）
Strong tidal dissipation in Io and Jupiter from astrometric observations
使“木卫一”成为太阳系中火山活动最活跃天体的极端地质活动，被认为是木星所引起的潮汐造成的，但关于当前的潮汐热的产生量是否高到足以生成所观察到的表面热流我们尚不清楚。Lainey等人，利用在1891年 和 2007年间获得的天文测量观测结果，通过跟踪“木卫一”上的潮汐耗散对木星的伽利略卫星轨道运动的影响，对这种潮汐耗散的值做出了估计。对“木卫一”来说，这个值与所观测到的表面热流非常相符合，说明“木卫一”近于热平衡。木星的耗散值接近根据该体系的长期演化可以推算出的其平均值的上限。（Letter p. 957; News & Views）
纳米机械振动的实现与观测（Nanomechanical vibrations）
Nanomechanical measurements of a superconducting qubit
制造出其振动运动纯粹为量子力学振动的微型机械结构，是物理学中的一个长期未能实现的目标，从基础角度来讲和从它们有可能促使实现的应用角度来讲都是这样。另一个同样重要的目标是，研究出一个观察和控制这种微小运动的方案来。LaHaye等人在这个方向上取得了重要进展：他们将一个微型机械振荡器耦合到了一个两级超导量子体系（量子位）上。该超导量子位的状态可通过其对振荡器之振动的影响来测量。这样一个耦合的器件配置最终应能够使运动的奇异量子状态的生成和测量成为可能。（Letterp. 960; News & Views）
始新世-渐新世过渡时期北半球状况（Seasonal adjustment）
Peierls distortion as a route to high thermoelectric performance in In4Se3-crystals
在距今大约3350万年前（始新世-渐新世过渡时期），地球的气候从“温室”变成“冰室”状态。大陆尺度的冰层大约这个时候出现在南极洲，同时大气中二氧化碳含量减少，但是，尤其对北半球高纬度地区而言，我们对当时的气候发生了什么变化相对来说一无所知。为了了解关于北半球状况的更多情况，Eldrett等人对挪威-格陵兰海中的海洋沉积物中所保存下来的陆地孢子和花粉进行了分析。他们发现，在始新世-渐新世过渡时期之前，最冷月平均温度下降了约5 °C，季节性增强了。（Letter p. 965）
寄生虫在个体层面上的适应行为（They are all individuals）
Adaptation and the evolution of parasite virulence in a connected world
关于适应性的传统观点是，它在生物个体层面上发挥作用，但关于在具有空间结构的种群中（在这种种群中扩散是有限的）感染蛾子和细菌的病毒毒性之演化的最新观测结果，却被解释为群体选择的例子。Wild等人在此用数学方法对以前的模型进行了延伸，发现扩散对寄生虫毒性的影响，可以完全在亲缘选择理论的范畴内被理解为寄生虫在个体层面上的一种适应行为。（Letter p. 983）
“成神经细胞瘤”的“拷贝数变异”（Copy number variation in neutroblastoma）
Copy number variation at 1q21.1 associated with neuroblastoma
“拷贝数变异”（CNVs）和“单核苷酸多态性”（SNPs）是人类表型变异的两个重要潜在来源。此前，只有SNPs被与癌症关联起来，但对胚系DNA剂量是人类多样性一个关键组成部分这一观点之认可程度的不断提高，使人们想到这样一个可能性：CNVs可能也影响对于这种癌症的易感性。现在，Disklin等人报告说，染色体1q21.1上的一个常见CNV与儿童癌症“成神经细胞瘤”有关，而且这一CNV内的一个转录体（以前我们不知道的“成神经细胞瘤”断点家族基因NBPF23）也参与了肿瘤形成的早期阶段。（Letter p.987）
罂粟PrpS基因的三个等位基因被克隆（Poppys’ self awareness）
Identification of the pollen self-incompatibility determinant in Papaver rhoeas
“自交不亲和性”是很多植物物种中的一个重要机制，用于通过确保拒绝自体花粉来防止近亲繁殖。它是由一个多等位基因的S-位点控制的，后者由花粉（雄性）和雌蕊（雌性）的S-决定因子构成。Wheeler等人克隆了一个具有高度多态性的、在花粉中表达的基因的三个等位基因；该基因名叫PrpS，来自普通罂粟，它在现有数据库中没有同源基因。PrpS是一种跨膜蛋白，其功能似乎是起花粉S-位点决定因子的作用。这一结果增加了我们对细胞-细胞识别体系的演化的认识。（Letter p. 992）
对微RNA调控因子本身的调控（Regulating the microRNA regulators）
The RNA-binding protein KSRP promotes the biogenesis of a subset of microRNAs
由于小RNA对基因表达的发展和调控有深远影响，所以它们自己的表达同样一定仅限于在正确的时间出现在正确的细胞中的正确的层面上。Michael Rosenfeld 和Witold Filipowicz的实验室之间的一个合作课题组报告说，RNA结合蛋白KSRP（“KH-型剪接调控蛋白”的缩写）调控一个亚组的微RNA的前体加工。如果这一调控机制被破坏，其效应在增殖、分化和凋亡上就可以被看到。所以，KSRP既参与mRNA的周转，又参与促进mRNA的表达。这项工作揭示了mi-RNA在调控基因表达上的复杂性的另一个层面。（Letter p. 1010）
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NEWS AND VIEWS
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Organometallic chemistry: Charting the course of catalysis
pp917-918
With palladium catalysts, chemists can manipulate ordinarily inert carbon-hydrogen bonds to build useful molecules from simple building blocks. How the catalysts guide this process has just become a bit clearer.
Gregory L. Hamilton and F. Dean Tostedoi:10.1038/459917a
http://www.nature.com/nature/journal/v459/n7249/full/459917a.html
Malaria: The gatekeeper revealed pp918-919
A molecular machine used by the malaria parasite to export its protein armoury into the host cell has at last been identified, providing researchers with a potentially invaluable therapeutic target.
Sarah B. Reiff and Boris Striepen
doi:10.1038/459918a
http://www.nature.com/nature/journal/v459/n7249/full/459918a.html
Biomechanics: Serpentine steps pp919-920
Combine theoretical modelling, friction measurements and observations of serpentine slithering. Together, they show that snakes are in effect just taking a walk even when moving at high speed.
Andrew J. Clark and Adam P. Summers
doi:10.1038/459919a
http://www.nature.com/nature/journal/v459/n7249/full/459919a.html
Planetary science: Io's escape pp920-921
According to the latest study, our witnessing of the volcanic splendour of Jupiter's moon Io might just be a lucky circumstance. The odds are that the satellite will become quiescent on its escape from orbital custody.
Gerald Schubert
doi:10.1038/459920a
http://www.nature.com/nature/journal/v459/n7249/full/459920a.html
Inflammation: Wound healing in zebrafish pp921-923
What is the first signal that directs the rapid influx of immune cells to a wound to stave off potential infection? A study in the zebrafish reveals an unusual but well-qualified candidate.
Paul Martin and Yi Feng
doi:10.1038/459921a
http://www.nature.com/nature/journal/v459/n7249/full/459921a.html
Condensed-matter physics: Coupled vibrations pp923-924
Demonstrating that macroscopic objects can display quantum behaviour, which is usually associated with the microscopic world of atoms, is a long-standing goal in physics. That goal is now within closer reach.
Pertti J. Hakonen and Mika A. Sillanpaa
doi:10.1038/459923a
http://www.nature.com/nature/journal/v459/n7249/full/459923a.html
Cell biology: Beyond the prion principle pp924-925
It seems that many misfolded proteins can act like prions [mdash] spreading disease by imparting their misshapen structure to normal cellularcounterparts. But how common are bona fide prions really?
Adriano Aguzzi
doi:10.1038/459924a
http://www.nature.com/nature/journal/v459/n7249/full/459924a.html
Correction p925
doi:10.1038/459925a
http://www.nature.com/nature/journal/v459/n7249/full/459925a.html
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FEATURE
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Unlocking the secrets of the genome pp927-930
Despite the successes of genomics, little is known about how genetic information produces complex organisms. A look at the crucial functional elements of fly and worm genomes could change that.
Susan E. Celniker et al.
doi:10.1038/459927a
http://www.nature.com/nature/journal/v459/n7249/full/459927a.html
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ARTICLES
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A Jurassic ceratosaur from China helps clarify avian digital
homologies pp940-944
The bird hand is thought to derive from the second, third and fourth digits of an ancestral five-digit hand. However, the three-fingered hand of theropod dinosaurs, which are the closest extinct relatives of birds, are thought to derive from the first, second and third digits. The discovery of a small, primitive herbivorous theropod from the Jurassic period of China with a stub of the first digit alongside more developed second, third and fourth digits, sheds light on this problem.
Xing Xu et al.
doi:10.1038/nature08124
Abstract:
http://www.nature.com/nature/journal/v459/n7249/abs/nature08124.html
Article:
http://www.nature.com/nature/journal/v459/n7249/full/nature08124.html
A newly discovered protein export machine in malaria parasites pp945-949
Malaria parasites reside in vacuoles during intracellular infection of erythrocytes and export many proteins into the host cell, a process that is essential for the virulence and viability of Plasmodium. Whereas transport across the parasite membrane is known to rely on the secretory pathway, the transporter
responsible for the translocation of proteins across the vacuole membrane is now identified.
Tania F. de Koning-Ward et al.
doi:10.1038/nature08104
Abstract:
http://www.nature.com/nature/journal/v459/n7249/abs/nature08104.html
Article:
http://www.nature.com/nature/journal/v459/n7249/full/nature08104.html
The Listeria transcriptional landscape from saprophytism to
virulence pp950-956
Listeria monocytogenes is responsible for severe food-borne infections. The first global comparative transcriptome analysis of this species reveals successive and coordinated global transcriptional changes during infection and points to previously unknown regulatory mechanisms in bacteria.
Alejandro Toledo-Arana et al.
doi:10.1038/nature08080
Abstract:
http://www.nature.com/nature/journal/v459/n7249/abs/nature08080.html
Article:
http://www.nature.com/nature/journal/v459/n7249/full/nature08080.html
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LETTERS
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Nanomechanical measurements of a superconducting qubit pp960-964
Fabricating tiny mechanical structures where the vibrational motion is
purely
quantum mechanical is a long-standing goal in physics, and a parallel goal
is
the development of a scheme for observing and controlling such tiny motions.
By coupling a tiny mechanical resonator to a superconducting two-level
quantum
system (qubit), the state of the superconducting qubit can be measured
through
its influence on the vibrations of the resonator, a demonstration of
nanomechanical
read-out of quantum interference.
M. D. LaHaye et al.
doi:10.1038/nature08093
Abstract:
http://www.nature.com/nature/journal/v459/n7249/abs/nature08093.html
Article:
http://www.nature.com/nature/journal/v459/n7249/full/nature08093.html
Peierls distortion as a route to high thermoelectric performance in
In4Se3-[dgr]
crystals pp965-968
Thermoelectric materials, which can convert heat into electricity, are of
great
interest for energy sustainability. The problem is the low efficiency of
these
materials, quantified by a coefficient, ZT, which for mid-temperature
materials
is usually around 1. The realization of a material, In4Se3-[delta], which
achieves
the ZT value of 1.48 at 705 K, could open up a new avenue in the research to
generate high ZT materials.
Jong-Soo Rhyee et al.
doi:10.1038/nature08088
Abstract:
http://www.nature.com/nature/journal/v459/n7249/abs/nature08088.html
Article:
http://www.nature.com/nature/journal/v459/n7249/full/nature08088.html
Increased seasonality through the Eocene to Oligocene transition in northern
high latitudes pp969-973
About 33.5 million years ago, at the Eocene-Oligocene transition, the
Earth's
climate switched from greenhouse to icehouse conditions. The analysis of
terrestrial spore and pollen evidence deposited in ocean sediments in the
Norwegian-Greenland Sea now reveals that cold-month mean temperatures
declined
by about 5 [deg]C prior to the Eocene-Oligocene transition and that
seasonality increased.
James S. Eldrett, David R. Greenwood, Ian C. Harding and Matthew Huber
doi:10.1038/nature08069
Abstract:
http://www.nature.com/nature/journal/v459/n7249/abs/nature08069.html
Article:
http://www.nature.com/nature/journal/v459/n7249/full/nature08069.html
Creep cavitation can establish a dynamic granular fluid pump in ductile
shear
zones pp974-977
Fluid migration in the middle crust is difficult to explain[mdash]the
environment
is considered too hot for a dynamic fracture-sustained permeability, as in
the
upper crust, and fluid pathways are generally too deformed to be controlled
by
equilibrium wetting angles that apply to hotter, deeper environments. Here,
synchroton X-ray tomography and scanning electron microscopy observations
are
used to formulate a model for fluid migration in shear zones which may
explain
fluid transfer through the middle crust.
F. Fusseis et al.
doi:10.1038/nature08051
Abstract:
http://www.nature.com/nature/journal/v459/n7249/abs/nature08051.html
Article:
http://www.nature.com/nature/journal/v459/n7249/full/nature08051.html
Colorado Plateau magmatism and uplift by warming of heterogeneous
lithosphere
pp978-982
There has been a long-standing debate about the forces that drove uplift of
the
low-relief and tectonically-stable Colorado plateau, which experienced about
2 km
of rock uplift without significant internal deformation. Warming of the
thicker,
more iron-depleted Colorado plateau lithosphere over 35-40 million years
following removal of the Farallon plate from beneath North America
is now proposed to be the primary mechanism for driving rock uplift.
Mousumi Roy, Thomas H. Jordan and Joel Pederson
doi:10.1038/nature08052
Abstract:
http://www.nature.com/nature/journal/v459/n7249/abs/nature08052.html
Article:
http://www.nature.com/nature/journal/v459/n7249/full/nature08052.html
Adaptation and the evolution of parasite virulence in a connected
world pp983-986
The evolution of lowered virulence in spatially structured populations with
limited dispersal has been suggested to be an example of adaptation at the
group
level. The extension of previous models now shows that the effect of
dispersal
can be understood within the framework of inclusive fitness theory,
demonstrating
that reduced virulence could be due to individual-level adaptation by the
parasite.
Geoff Wild, Andy Gardner and Stuart A. West
doi:10.1038/nature08071
Abstract:
http://www.nature.com/nature/journal/v459/n7249/abs/nature08071.html
Article:
http://www.nature.com/nature/journal/v459/n7249/full/nature08071.html
Copy number variation at 1q21.1 associated with neuroblastoma pp987-991
Copy number variations (CNVs) and single nucleotide polymorphisms (SNPs) are
two
important potential sources of phenotypic variation in humans; however, only
SNPs
have been associated with cancer. Here, a CNV at 1q21.1 is shown to be
associated
with neuroblastoma, and a transcript within this CNV, NBPF23, is implicated
in early
tumorigenesis of the disease.
Sharon J. Diskin et al.
doi:10.1038/nature08035
Abstract:
http://www.nature.com/nature/journal/v459/n7249/abs/nature08035.html
Article:
http://www.nature.com/nature/journal/v459/n7249/full/nature08035.html
Identification of the pollen self-incompatibility determinant in Papaver
rhoeas pp992-995
Self-incompatibility is an important mechanism used in many species to
prevent i
nbreeding by ensuring rejection of 'self' pollen. The cloning of three
alleles of
a highly polymorphic pollen-expressed gene, PrpS (Papaver rhoeas pollen S),
now
provides evidence that it encodes the pollen S locus determinant and adds to
our
knowledge of the evolution of cell-cell recognition systems.
Michael J. Wheeler et al.
doi:10.1038/nature08027
Abstract:
http://www.nature.com/nature/journal/v459/n7249/abs/nature08027.html
Article:
http://www.nature.com/nature/journal/v459/n7249/full/nature08027.html
A tissue-scale gradient of hydrogen peroxide mediates rapid wound detection
in zebrafish pp996-999
In animals, within minutes of wounding, leukocytes are recruited to the site
of
injury across distances of hundreds of micrometres. Early leukocyte
recruitment
after injury is now shown to be driven by the establishment of an H2O2
gradient
from the epithelium to the vasculature in zebrafish.
Philipp Niethammer, Clemens Grabher, A. Thomas Look and Timothy J. Mitchison
doi:10.1038/nature08119
Abstract:
http://www.nature.com/nature/journal/v459/n7249/abs/nature08119.html
Article:
http://www.nature.com/nature/journal/v459/n7249/full/nature08119.html
CCR7 signalling as an essential regulator of CNS infiltration in T-cell
leukaemia
pp1000-1004
T-cell acute lymphoblastic leukaemia (T-ALL) patients are at an increased
risk of
central nervous system (CNS) relapse, and yet, despite its clinical
importance,
little is known about the mechanism of leukaemic cell infiltration of the
CNS.
Here, using T-ALL animal modelling and gene-expression profiling, the
chemokine
receptor CCR7 is shown to be the essential adhesion signal required for the
targeting
of leukaemic T cells into the CNS.
Silvia Buonamici et al.
doi:10.1038/nature08020
Abstract:
http://www.nature.com/nature/journal/v459/n7249/abs/nature08020.html
Article:
http://www.nature.com/nature/journal/v459/n7249/full/nature08020.html
Genes that mediate breast cancer metastasis to the brain pp1005-1009
Little is known about the mechanisms by which breast cancer cells
metastasize to
the brain. By performing gene expression analysis on cells that
preferentially
infiltrate the brain it has now been possible to identify three genes that
are
involved in this process, two of which[mdash]COX2 and HBEGF[mdash]have
previously
been shown to mediate breast cancer metastasis to the lung.
Paula D. Bos et al.
doi:10.1038/nature08021
Abstract:
http://www.nature.com/nature/journal/v459/n7249/abs/nature08021.html
Article:
http://www.nature.com/nature/journal/v459/n7249/full/nature08021.html
The RNA-binding protein KSRP promotes the biogenesis of a subset of
microRNAs
pp1010-1014
MicroRNAs (miRNAs) have a role in down-regulating gene expression, and the
levels
of specific miRNAs are important for correct embryonic development; however,
the
mechanisms by which this is regulated are unknown. The splicing regulatory
protein,
KSRP, is now found to regulate the precursor processing of a subset of
miRNAs, and
its disruption leads to effects on proliferation, differentiation and
apoptosis.
Michele Trabucchi et al.
doi:10.1038/nature08025
Abstract:
http://www.nature.com/nature/journal/v459/n7249/abs/nature08025.html
Article:
http://www.nature.com/nature/journal/v459/n7249/full/nature08025.html
Structure and mechanism of a bacterial light-regulated cyclic nucleotide
phosphodiesterase pp1015-1018
Although structures of single-domain BLUF proteins[mdash]a photoreceptor
protein
domain that senses blue light[mdash]have been determined, there have been no
reports
of the structure of a BLUF protein containing a functional output domain;
for this
reason, the mechanism of light activation has remained enigmatic. The first
biochemical, structural and mechanistic characterization of a full-length,
active
photoreceptor containing a BLUF sensor domain and a phosphodiesterase EAL
output
domain is now reported.
Thomas R. M. Barends et al.
doi:10.1038/nature07966
Abstract:
http://www.nature.com/nature/journal/v459/n7249/abs/nature07966.html
Article:
http://www.nature.com/nature/journal/v459/n7249/full/nature07966.html
----------------------
FUTURES
----------------------
Totipotent p1026
Caught in a trap.
Catherine Krahe
doi:10.1038/4591026a
http://www.nature.com/nature/journal/v459/n7249/full/4591026a.html
Emergence and pandemic potential of swine-origin H1N1 influenza virus
随着H1N1猪流感病毒疫情的爆发目前在世界卫生组织分类系统上被置于5级预警（6级则表示这种疫情的大范围流行已经发生），Gabriele Neumann、Takeshi Noda和Yoshihiro Kawaoka对关于H1N1病毒的出现及流行潜力的现有知识进行了盘点，并将以前传播的流感病毒毒株与“猪流感”毒株的抗原及病理性质进行了对比。他们得出的结论是，国际社会对于应对该疾病的大范围流行并没有做好准备，所储备的抗病毒药物并不充足，而且疫苗的生产也比较缓慢。关于我们今后是否能够准备得更好一些，他们的结论是，虽然我们已经了解了很多，但对于病毒跨物种传播、重组及人与人的传播等，我们还需要了解更多。本期封面图片是H1N1病毒的一个扫描电子显微照片（A/California/04/09），是在其从一个被病毒感染的细胞出现时拍到的。H1N1病毒颗粒大部分是细丝状，而不是球形，可以看到它覆盖在细胞表面上。（Review p. 931）
恐龙爪向翅膀演化的证据（A dinosaur in the hand）
A Jurassic ceratosaur from China helps clarify avian digital homologies
关于恐龙今天仍旧和我们在一起（如鸟类）的观点现已被普遍接受。但还有一个棘手的问题：鸟的前爪（现已退化、嵌入在翅膀中）被认为是从一个先祖的五指爪的第二、第三和第四指演化而来，而与鸟类亲缘关系最近的已灭绝物种（即兽脚类恐龙）的三指爪似乎是从第一、第二和第三指演化而来；一种爪何以变成了另一种？随着在中国西部准噶尔盆地侏罗纪地层中一个小型、原始兽脚类食草恐龙化石的发现，在恐龙研究方面成果颇丰的徐星及其同事可能已经解决了这一问题。这一生物生活在距今大约1.55亿年前，除了有发育较为充分的第二、第三和第四指外，还有第一指的一个残迹。这一原始恐龙的腕骨更像与二、三和四指相关的腕骨，但指骨本身更像一、二和三指。这表明，恐龙爪向翅膀的演化涉及腕和指所发生的复杂发育变化，而且这一新发现的恐龙让我们有机会一瞥当时正在发生的这种变化。（Article p. 940）
抗疟疾药物的新目标（Antimalaria target）
A newly discovered protein export machine in malaria parasites
在红细胞的细胞内感染过程中，疟原虫寄生在液泡中，并从那里将很多蛋白输出到宿主细胞中。这些蛋白的分泌在镰刀形疟原虫的感染力和生存力方面扮演一个重要角色。现在，这一过程中所涉及的蛋白输出机构已被确定。该机构被称为PTEX（它表示镰刀形疟原虫的Translocon of Exported蛋白），它是一个存在于液泡膜中的以ATP为动力的复合物，可能为抗疟疾药物提供一个新目标。（Article p. 945; News & Views）
李斯特菌从腐生菌转化为致病菌的奥秘（Listeria’s double life）
The Listeria transcriptional landscape from saprophytism to virulence
单核增生李斯特菌（Listeria monocytogenes）是一种常见的土壤细菌，在土壤中它是一种腐生菌，以死亡的和正在腐烂的有机物为食。它也是某些食物（主要是鲜奶产品）中的一种污染物，能引起严重食物中毒。关于在一系列不同生长条件下单核增生李斯特菌转录组（细胞中的全部mRNA转录体）的一项新的研究，搞清了从腐生到致病生活方式的这种转变的性质。该研究的数据显示了一个转录程序，其复杂程度出乎意料，它涉及50个非编码RNA，同时还有一系列新的调控RNA，包括几个长反义RNA。在感染过程中，李斯特菌通过协调的全组转录变化成功重塑其转录程序，其中某些非编码RNA优先在小肠或血液中生长的细胞中表达。（Article p. 950）
“木卫一”近于热平衡（Io’s tidal volcanoes）
Strong tidal dissipation in Io and Jupiter from astrometric observations
使“木卫一”成为太阳系中火山活动最活跃天体的极端地质活动，被认为是木星所引起的潮汐造成的，但关于当前的潮汐热的产生量是否高到足以生成所观察到的表面热流我们尚不清楚。Lainey等人，利用在1891年 和 2007年间获得的天文测量观测结果，通过跟踪“木卫一”上的潮汐耗散对木星的伽利略卫星轨道运动的影响，对这种潮汐耗散的值做出了估计。对“木卫一”来说，这个值与所观测到的表面热流非常相符合，说明“木卫一”近于热平衡。木星的耗散值接近根据该体系的长期演化可以推算出的其平均值的上限。（Letter p. 957; News & Views）
纳米机械振动的实现与观测（Nanomechanical vibrations）
Nanomechanical measurements of a superconducting qubit
制造出其振动运动纯粹为量子力学振动的微型机械结构，是物理学中的一个长期未能实现的目标，从基础角度来讲和从它们有可能促使实现的应用角度来讲都是这样。另一个同样重要的目标是，研究出一个观察和控制这种微小运动的方案来。LaHaye等人在这个方向上取得了重要进展：他们将一个微型机械振荡器耦合到了一个两级超导量子体系（量子位）上。该超导量子位的状态可通过其对振荡器之振动的影响来测量。这样一个耦合的器件配置最终应能够使运动的奇异量子状态的生成和测量成为可能。（Letterp. 960; News & Views）
始新世-渐新世过渡时期北半球状况（Seasonal adjustment）
Peierls distortion as a route to high thermoelectric performance in In4Se3-crystals
在距今大约3350万年前（始新世-渐新世过渡时期），地球的气候从“温室”变成“冰室”状态。大陆尺度的冰层大约这个时候出现在南极洲，同时大气中二氧化碳含量减少，但是，尤其对北半球高纬度地区而言，我们对当时的气候发生了什么变化相对来说一无所知。为了了解关于北半球状况的更多情况，Eldrett等人对挪威-格陵兰海中的海洋沉积物中所保存下来的陆地孢子和花粉进行了分析。他们发现，在始新世-渐新世过渡时期之前，最冷月平均温度下降了约5 °C，季节性增强了。（Letter p. 965）
寄生虫在个体层面上的适应行为（They are all individuals）
Adaptation and the evolution of parasite virulence in a connected world
关于适应性的传统观点是，它在生物个体层面上发挥作用，但关于在具有空间结构的种群中（在这种种群中扩散是有限的）感染蛾子和细菌的病毒毒性之演化的最新观测结果，却被解释为群体选择的例子。Wild等人在此用数学方法对以前的模型进行了延伸，发现扩散对寄生虫毒性的影响，可以完全在亲缘选择理论的范畴内被理解为寄生虫在个体层面上的一种适应行为。（Letter p. 983）
“成神经细胞瘤”的“拷贝数变异”（Copy number variation in neutroblastoma）
Copy number variation at 1q21.1 associated with neuroblastoma
“拷贝数变异”（CNVs）和“单核苷酸多态性”（SNPs）是人类表型变异的两个重要潜在来源。此前，只有SNPs被与癌症关联起来，但对胚系DNA剂量是人类多样性一个关键组成部分这一观点之认可程度的不断提高，使人们想到这样一个可能性：CNVs可能也影响对于这种癌症的易感性。现在，Disklin等人报告说，染色体1q21.1上的一个常见CNV与儿童癌症“成神经细胞瘤”有关，而且这一CNV内的一个转录体（以前我们不知道的“成神经细胞瘤”断点家族基因NBPF23）也参与了肿瘤形成的早期阶段。（Letter p.987）
罂粟PrpS基因的三个等位基因被克隆（Poppys’ self awareness）
Identification of the pollen self-incompatibility determinant in Papaver rhoeas
“自交不亲和性”是很多植物物种中的一个重要机制，用于通过确保拒绝自体花粉来防止近亲繁殖。它是由一个多等位基因的S-位点控制的，后者由花粉（雄性）和雌蕊（雌性）的S-决定因子构成。Wheeler等人克隆了一个具有高度多态性的、在花粉中表达的基因的三个等位基因；该基因名叫PrpS，来自普通罂粟，它在现有数据库中没有同源基因。PrpS是一种跨膜蛋白，其功能似乎是起花粉S-位点决定因子的作用。这一结果增加了我们对细胞-细胞识别体系的演化的认识。（Letter p. 992）
对微RNA调控因子本身的调控（Regulating the microRNA regulators）
The RNA-binding protein KSRP promotes the biogenesis of a subset of microRNAs
由于小RNA对基因表达的发展和调控有深远影响，所以它们自己的表达同样一定仅限于在正确的时间出现在正确的细胞中的正确的层面上。Michael Rosenfeld 和Witold Filipowicz的实验室之间的一个合作课题组报告说，RNA结合蛋白KSRP（“KH-型剪接调控蛋白”的缩写）调控一个亚组的微RNA的前体加工。如果这一调控机制被破坏，其效应在增殖、分化和凋亡上就可以被看到。所以，KSRP既参与mRNA的周转，又参与促进mRNA的表达。这项工作揭示了mi-RNA在调控基因表达上的复杂性的另一个层面。（Letter p. 1010）
----------------------
NEWS AND VIEWS
----------------------
Organometallic chemistry: Charting the course of catalysis
pp917-918
With palladium catalysts, chemists can manipulate ordinarily inert carbon-hydrogen bonds to build useful molecules from simple building blocks. How the catalysts guide this process has just become a bit clearer.
Gregory L. Hamilton and F. Dean Tostedoi:10.1038/459917a
http://www.nature.com/nature/journal/v459/n7249/full/459917a.html
Malaria: The gatekeeper revealed pp918-919
A molecular machine used by the malaria parasite to export its protein armoury into the host cell has at last been identified, providing researchers with a potentially invaluable therapeutic target.
Sarah B. Reiff and Boris Striepen
doi:10.1038/459918a
http://www.nature.com/nature/journal/v459/n7249/full/459918a.html
Biomechanics: Serpentine steps pp919-920
Combine theoretical modelling, friction measurements and observations of serpentine slithering. Together, they show that snakes are in effect just taking a walk even when moving at high speed.
Andrew J. Clark and Adam P. Summers
doi:10.1038/459919a
http://www.nature.com/nature/journal/v459/n7249/full/459919a.html
Planetary science: Io's escape pp920-921
According to the latest study, our witnessing of the volcanic splendour of Jupiter's moon Io might just be a lucky circumstance. The odds are that the satellite will become quiescent on its escape from orbital custody.
Gerald Schubert
doi:10.1038/459920a
http://www.nature.com/nature/journal/v459/n7249/full/459920a.html
Inflammation: Wound healing in zebrafish pp921-923
What is the first signal that directs the rapid influx of immune cells to a wound to stave off potential infection? A study in the zebrafish reveals an unusual but well-qualified candidate.
Paul Martin and Yi Feng
doi:10.1038/459921a
http://www.nature.com/nature/journal/v459/n7249/full/459921a.html
Condensed-matter physics: Coupled vibrations pp923-924
Demonstrating that macroscopic objects can display quantum behaviour, which is usually associated with the microscopic world of atoms, is a long-standing goal in physics. That goal is now within closer reach.
Pertti J. Hakonen and Mika A. Sillanpaa
doi:10.1038/459923a
http://www.nature.com/nature/journal/v459/n7249/full/459923a.html
Cell biology: Beyond the prion principle pp924-925
It seems that many misfolded proteins can act like prions [mdash] spreading disease by imparting their misshapen structure to normal cellularcounterparts. But how common are bona fide prions really?
Adriano Aguzzi
doi:10.1038/459924a
http://www.nature.com/nature/journal/v459/n7249/full/459924a.html
Correction p925
doi:10.1038/459925a
http://www.nature.com/nature/journal/v459/n7249/full/459925a.html
----------------------
FEATURE
----------------------
Unlocking the secrets of the genome pp927-930
Despite the successes of genomics, little is known about how genetic information produces complex organisms. A look at the crucial functional elements of fly and worm genomes could change that.
Susan E. Celniker et al.
doi:10.1038/459927a
http://www.nature.com/nature/journal/v459/n7249/full/459927a.html
----------------------
ARTICLES
----------------------
A Jurassic ceratosaur from China helps clarify avian digital
homologies pp940-944
The bird hand is thought to derive from the second, third and fourth digits of an ancestral five-digit hand. However, the three-fingered hand of theropod dinosaurs, which are the closest extinct relatives of birds, are thought to derive from the first, second and third digits. The discovery of a small, primitive herbivorous theropod from the Jurassic period of China with a stub of the first digit alongside more developed second, third and fourth digits, sheds light on this problem.
Xing Xu et al.
doi:10.1038/nature08124
Abstract:
http://www.nature.com/nature/journal/v459/n7249/abs/nature08124.html
Article:
http://www.nature.com/nature/journal/v459/n7249/full/nature08124.html
A newly discovered protein export machine in malaria parasites pp945-949
Malaria parasites reside in vacuoles during intracellular infection of erythrocytes and export many proteins into the host cell, a process that is essential for the virulence and viability of Plasmodium. Whereas transport across the parasite membrane is known to rely on the secretory pathway, the transporter
responsible for the translocation of proteins across the vacuole membrane is now identified.
Tania F. de Koning-Ward et al.
doi:10.1038/nature08104
Abstract:
http://www.nature.com/nature/journal/v459/n7249/abs/nature08104.html
Article:
http://www.nature.com/nature/journal/v459/n7249/full/nature08104.html
The Listeria transcriptional landscape from saprophytism to
virulence pp950-956
Listeria monocytogenes is responsible for severe food-borne infections. The first global comparative transcriptome analysis of this species reveals successive and coordinated global transcriptional changes during infection and points to previously unknown regulatory mechanisms in bacteria.
Alejandro Toledo-Arana et al.
doi:10.1038/nature08080
Abstract:
http://www.nature.com/nature/journal/v459/n7249/abs/nature08080.html
Article:
http://www.nature.com/nature/journal/v459/n7249/full/nature08080.html
----------------------
LETTERS
----------------------
Nanomechanical measurements of a superconducting qubit pp960-964
Fabricating tiny mechanical structures where the vibrational motion is
purely
quantum mechanical is a long-standing goal in physics, and a parallel goal
is
the development of a scheme for observing and controlling such tiny motions.
By coupling a tiny mechanical resonator to a superconducting two-level
quantum
system (qubit), the state of the superconducting qubit can be measured
through
its influence on the vibrations of the resonator, a demonstration of
nanomechanical
read-out of quantum interference.
M. D. LaHaye et al.
doi:10.1038/nature08093
Abstract:
http://www.nature.com/nature/journal/v459/n7249/abs/nature08093.html
Article:
http://www.nature.com/nature/journal/v459/n7249/full/nature08093.html
Peierls distortion as a route to high thermoelectric performance in
In4Se3-[dgr]
crystals pp965-968
Thermoelectric materials, which can convert heat into electricity, are of
great
interest for energy sustainability. The problem is the low efficiency of
these
materials, quantified by a coefficient, ZT, which for mid-temperature
materials
is usually around 1. The realization of a material, In4Se3-[delta], which
achieves
the ZT value of 1.48 at 705 K, could open up a new avenue in the research to
generate high ZT materials.
Jong-Soo Rhyee et al.
doi:10.1038/nature08088
Abstract:
http://www.nature.com/nature/journal/v459/n7249/abs/nature08088.html
Article:
http://www.nature.com/nature/journal/v459/n7249/full/nature08088.html
Increased seasonality through the Eocene to Oligocene transition in northern
high latitudes pp969-973
About 33.5 million years ago, at the Eocene-Oligocene transition, the
Earth's
climate switched from greenhouse to icehouse conditions. The analysis of
terrestrial spore and pollen evidence deposited in ocean sediments in the
Norwegian-Greenland Sea now reveals that cold-month mean temperatures
declined
by about 5 [deg]C prior to the Eocene-Oligocene transition and that
seasonality increased.
James S. Eldrett, David R. Greenwood, Ian C. Harding and Matthew Huber
doi:10.1038/nature08069
Abstract:
http://www.nature.com/nature/journal/v459/n7249/abs/nature08069.html
Article:
http://www.nature.com/nature/journal/v459/n7249/full/nature08069.html
Creep cavitation can establish a dynamic granular fluid pump in ductile
shear
zones pp974-977
Fluid migration in the middle crust is difficult to explain[mdash]the
environment
is considered too hot for a dynamic fracture-sustained permeability, as in
the
upper crust, and fluid pathways are generally too deformed to be controlled
by
equilibrium wetting angles that apply to hotter, deeper environments. Here,
synchroton X-ray tomography and scanning electron microscopy observations
are
used to formulate a model for fluid migration in shear zones which may
explain
fluid transfer through the middle crust.
F. Fusseis et al.
doi:10.1038/nature08051
Abstract:
http://www.nature.com/nature/journal/v459/n7249/abs/nature08051.html
Article:
http://www.nature.com/nature/journal/v459/n7249/full/nature08051.html
Colorado Plateau magmatism and uplift by warming of heterogeneous
lithosphere
pp978-982
There has been a long-standing debate about the forces that drove uplift of
the
low-relief and tectonically-stable Colorado plateau, which experienced about
2 km
of rock uplift without significant internal deformation. Warming of the
thicker,
more iron-depleted Colorado plateau lithosphere over 35-40 million years
following removal of the Farallon plate from beneath North America
is now proposed to be the primary mechanism for driving rock uplift.
Mousumi Roy, Thomas H. Jordan and Joel Pederson
doi:10.1038/nature08052
Abstract:
http://www.nature.com/nature/journal/v459/n7249/abs/nature08052.html
Article:
http://www.nature.com/nature/journal/v459/n7249/full/nature08052.html
Adaptation and the evolution of parasite virulence in a connected
world pp983-986
The evolution of lowered virulence in spatially structured populations with
limited dispersal has been suggested to be an example of adaptation at the
group
level. The extension of previous models now shows that the effect of
dispersal
can be understood within the framework of inclusive fitness theory,
demonstrating
that reduced virulence could be due to individual-level adaptation by the
parasite.
Geoff Wild, Andy Gardner and Stuart A. West
doi:10.1038/nature08071
Abstract:
http://www.nature.com/nature/journal/v459/n7249/abs/nature08071.html
Article:
http://www.nature.com/nature/journal/v459/n7249/full/nature08071.html
Copy number variation at 1q21.1 associated with neuroblastoma pp987-991
Copy number variations (CNVs) and single nucleotide polymorphisms (SNPs) are
two
important potential sources of phenotypic variation in humans; however, only
SNPs
have been associated with cancer. Here, a CNV at 1q21.1 is shown to be
associated
with neuroblastoma, and a transcript within this CNV, NBPF23, is implicated
in early
tumorigenesis of the disease.
Sharon J. Diskin et al.
doi:10.1038/nature08035
Abstract:
http://www.nature.com/nature/journal/v459/n7249/abs/nature08035.html
Article:
http://www.nature.com/nature/journal/v459/n7249/full/nature08035.html
Identification of the pollen self-incompatibility determinant in Papaver
rhoeas pp992-995
Self-incompatibility is an important mechanism used in many species to
prevent i
nbreeding by ensuring rejection of 'self' pollen. The cloning of three
alleles of
a highly polymorphic pollen-expressed gene, PrpS (Papaver rhoeas pollen S),
now
provides evidence that it encodes the pollen S locus determinant and adds to
our
knowledge of the evolution of cell-cell recognition systems.
Michael J. Wheeler et al.
doi:10.1038/nature08027
Abstract:
http://www.nature.com/nature/journal/v459/n7249/abs/nature08027.html
Article:
http://www.nature.com/nature/journal/v459/n7249/full/nature08027.html
A tissue-scale gradient of hydrogen peroxide mediates rapid wound detection
in zebrafish pp996-999
In animals, within minutes of wounding, leukocytes are recruited to the site
of
injury across distances of hundreds of micrometres. Early leukocyte
recruitment
after injury is now shown to be driven by the establishment of an H2O2
gradient
from the epithelium to the vasculature in zebrafish.
Philipp Niethammer, Clemens Grabher, A. Thomas Look and Timothy J. Mitchison
doi:10.1038/nature08119
Abstract:
http://www.nature.com/nature/journal/v459/n7249/abs/nature08119.html
Article:
http://www.nature.com/nature/journal/v459/n7249/full/nature08119.html
CCR7 signalling as an essential regulator of CNS infiltration in T-cell
leukaemia
pp1000-1004
T-cell acute lymphoblastic leukaemia (T-ALL) patients are at an increased
risk of
central nervous system (CNS) relapse, and yet, despite its clinical
importance,
little is known about the mechanism of leukaemic cell infiltration of the
CNS.
Here, using T-ALL animal modelling and gene-expression profiling, the
chemokine
receptor CCR7 is shown to be the essential adhesion signal required for the
targeting
of leukaemic T cells into the CNS.
Silvia Buonamici et al.
doi:10.1038/nature08020
Abstract:
http://www.nature.com/nature/journal/v459/n7249/abs/nature08020.html
Article:
http://www.nature.com/nature/journal/v459/n7249/full/nature08020.html
Genes that mediate breast cancer metastasis to the brain pp1005-1009
Little is known about the mechanisms by which breast cancer cells
metastasize to
the brain. By performing gene expression analysis on cells that
preferentially
infiltrate the brain it has now been possible to identify three genes that
are
involved in this process, two of which[mdash]COX2 and HBEGF[mdash]have
previously
been shown to mediate breast cancer metastasis to the lung.
Paula D. Bos et al.
doi:10.1038/nature08021
Abstract:
http://www.nature.com/nature/journal/v459/n7249/abs/nature08021.html
Article:
http://www.nature.com/nature/journal/v459/n7249/full/nature08021.html
The RNA-binding protein KSRP promotes the biogenesis of a subset of
microRNAs
pp1010-1014
MicroRNAs (miRNAs) have a role in down-regulating gene expression, and the
levels
of specific miRNAs are important for correct embryonic development; however,
the
mechanisms by which this is regulated are unknown. The splicing regulatory
protein,
KSRP, is now found to regulate the precursor processing of a subset of
miRNAs, and
its disruption leads to effects on proliferation, differentiation and
apoptosis.
Michele Trabucchi et al.
doi:10.1038/nature08025
Abstract:
http://www.nature.com/nature/journal/v459/n7249/abs/nature08025.html
Article:
http://www.nature.com/nature/journal/v459/n7249/full/nature08025.html
Structure and mechanism of a bacterial light-regulated cyclic nucleotide
phosphodiesterase pp1015-1018
Although structures of single-domain BLUF proteins[mdash]a photoreceptor
protein
domain that senses blue light[mdash]have been determined, there have been no
reports
of the structure of a BLUF protein containing a functional output domain;
for this
reason, the mechanism of light activation has remained enigmatic. The first
biochemical, structural and mechanistic characterization of a full-length,
active
photoreceptor containing a BLUF sensor domain and a phosphodiesterase EAL
output
domain is now reported.
Thomas R. M. Barends et al.
doi:10.1038/nature07966
Abstract:
http://www.nature.com/nature/journal/v459/n7249/abs/nature07966.html
Article:
http://www.nature.com/nature/journal/v459/n7249/full/nature07966.html
----------------------
FUTURES
----------------------
Totipotent p1026
Caught in a trap.
Catherine Krahe
doi:10.1038/4591026a
http://www.nature.com/nature/journal/v459/n7249/full/4591026a.html
环境科学之家（http://www.eschina.org.cn/）
| 《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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