2007年10月18日Nature中文摘要
时间:2007-10-26 10:33 来源:科学时报 作者:admin 点击:次
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封面故事：一位了不起的父亲 Hugh Rienhoff的女儿出生时患有一种罕见的遗传病，这种病影响其肌肉发育。 该疾病与“马凡氏症”相似，但心血管症状是不同的。它类似于“毕耳氏症”， 而且可能是“马凡氏症”或“毕耳氏症”的一种神秘病例。当传统方法未能做出 诊断时，Rienhoff决定进行一项个人基因组研究，对其女儿的DNA进行彻底分 析，甚至自己来确定其女儿基因组某些部分的序列。这是一个突破性的决定。最 后，他获得了关于其女儿临床史的一个“表现型列表”（phenotype spreadsheet），为了解这种罕见的遗传疾病提供了宝贵的信息，也为可能有助 于控制这种疾病的治疗方法提供了线索。故事到此还没有结束，因为还没有做出 明确的诊断，但这项工作还在继续。Rienhoff也并没有到此为止：他现在已建立 了一个网站，名为“MyDaughtersDNA.org”；这是一项善举，意在与他人分享自 己所获得的知识，并对面临类似困境的其他家庭提供帮助。本期Nature的封面照 片就是这父女两人，是在几星期前由Cody Pickens拍摄的。（News Feature p. 773; www.nature.com/podcast） 关于细菌与宿主之间相处关系的一个假说（Getting to know you） The equilibria that allow bacterial persistence in human hosts 微生物在宿主体内的持久存在通常并不是偶然的，而是反映了具有两种或更多不 同生命形式的生物的同时出现。有这样一个假说：对微生物和宿主来说都存在一 种选择，这种选择能使双方对于涉及寄生或共生的一种生活的适应性最大化，符 合一种稳定的进化策略。Martin Blaser 和 Denise Kirschner进一步发展了这 一假说。他们开发出一个平衡模型，该模型能够解释人体中微生物之间三种很不 相同的互动类型的存在，它们分别涉及幽门螺杆菌（Helicobacter pylori）、 伤寒沙门氏菌（Salmonella typhi）和结核分枝杆菌（Mycobacterium tuberculosis）。（Hypothesis p. 843） 人类基因组单体型图第二代版本问世（HapMap2 raises the bar） A second generation human haplotype map of over 3.1 million SNPs “国际人类基因组单体型图研究项目联合体”（International HapMap Consortium）已经完成人类基因组单体型图第二代版本。第二代版本的人类基因 组单体型图比最初版本对人类遗传变异做了更广泛的描绘，所包括的基因标记的 数量是最初版本的三倍（Article p. 851）。最初版本的人类基因组单体型图使 在整个基因组范围内进行大规模关联研究成为可能。本期Nature介绍了第二代版 本的人类基因组单体型图何以能使这种类型的研究工作更进一步：Sabeti等人在 以前工作的基础上，试图寻找人类基因上积极自然选择的标志。现在由于新增了 很多基因标记，他们发现了三例基于地域的明显的族群特定性选择，分别涉及与 西非的Lassa病毒、与欧洲的皮肤色素沉积和与亚洲的毛囊发育等相关的基因 对，他们还对这些基因对与人类生物学有何关系进行了推测。（Letter p. 851） 幽门螺杆菌的一种粘合素受体（Helicobacter targets integrin） Helicobacter exploits integrin for type IV secretion and kinase activation 粘合素（Integrins）是一个重要的细胞粘附受体家族，参与各种不同的信号作 用过程，是若干种细菌和病毒病原体粘附或入侵的目标。现在，一种粘合素已被 识别出是肠道病原体幽门螺杆菌的受体。该病原体的CagL pilus蛋白可结合到宿 主细胞表面受体粘合素α5β1上，这会触发致癌蛋白CagA（细胞毒素相关的基因 A）被注射进宿主细胞中。这项工作表明，CagL是治疗由一些幽门螺杆菌菌种引 起的肠道疾病的一个可能的药物作用目标。（Article p. 862; News & Views） 双星体系M33 X-7中的黑洞质量被确定（A black hole writ large） A 15.65-solar-mass black hole in an eclipsing binary in the nearby spiral galaxy M 33 计算一个遥远天体的重量（准确地说是质量）很重要，因为重量在确定其行为中 起很大作用。黑洞是天文学家非常感兴趣的，但却不是容易研究的目标。确定一 个黑洞重量的通常方法是确定其对附近某个天体的引力，现在天文学家已经对在 最近发现的双星体系M33 X-7（该双星体系在附近星系Messier 33中）的一个黑 洞做到了这一点。这个黑洞的质量为15.7个太阳质量，是已知质量最大的黑洞。 它的伴星是已知质量最大的恒星之一，约为70个太阳质量，而M33 X-7要比其他 任何已经确定的黑洞远16倍。（Letter p. 872; News & Views） 超导体在磁场作用下向绝缘体的转变（Island hopping） Nature of the superconductor–insulator transition in disordered superconductors 当一种超导薄膜变得紊乱、并处在一个越来越强的磁场中时，便会达到一个临界 点，在这一点上，它会发生一个从超导态向绝缘态过渡的转变。Dubi等人利用数 值模拟来了解这一转变（或者说，正如其模拟结果所表明的那样，应该是两种类 型的转变）的性质。紊乱的关键效应是生成具有强超导性的“岛屿”，它们被只 有微弱超导性的区域联系在一起。在弱紊乱的情况下，磁场不断增强最终会破坏 整个材料的超导状态，导致一种绝缘体的产生。当紊乱较强时，超导性会持久存 在于上述“岛屿”中，磁场效应是抑制它们之间的耦合，从而也导致一种绝缘 态。这些发现对于高温超导体研究可能有意义，在高温超导体中，内在紊乱被认 为扮演一个角色。（Letter p. 876） 一种新型光伏纳米线（WIRED FOR SUN） Coaxial silicon nanowires as solar cells and nanoelectronic power sources 一种基于共轴硅纳米线的新装置，显示其作为用在太阳能电池和纳米电子电源中 的一种小型光伏元件的潜力。该纳米线由硅做成，具有三种不同类型的电导性， 排列成共轴壳。入射光在外层的“n-型”壳中产生电子，同时它们的正空穴被 “扫”进中央的一个“p-型”层中。来自该光伏纳米线的电流可用来驱动功能性 纳米电子传感器和逻辑门。（Letter p. 885） 造成冰期-间冰期大气中二氧化碳浓度变化的过程（Out of the abyss） Carbon dioxide release from the North Pacific abyss during the last deglaciation 大气中二氧化碳浓度在过去200万年间曾经发生显著的变化，它们在寒冷的冰河 期相对较低，而在温暖的间冰期则相对较高。造成这些变化的过程目前仍然比较 模糊：人们认为，碳在冰河期可能被储存在深海中（当时深水环流比较缓慢）， 而在向间冰期过渡中则被释放出来，因为深海水的交换增加了，但来自这一时期 的直接证据非常少。现在，Galbraith等人利用来自海洋沉积物的地球化学记录 来对这一问题进行探索。他们发现，富含二氧化碳的一个交换状况很差的水体在 上次冰期极盛期（Last Glacial Maximum）占据着北太平洋， 深海交换在冰河 消退过程中增加了，将所存储的二氧化碳释放了出来。（Letter p. 890） 能够在缺氧条件下利用丙烷和丁烷的细菌（Natural gas guzzlers） Anaerobic oxidation of short-chain hydrocarbons by marine sulphate-reducing bacteria 人们对在海洋渗出气体中生活的生物、尤其是依靠甲烷生存的微生物的兴趣日趋 浓厚。令人吃惊的是，对于天然气中其他含量较多的烃类（乙烷、丙烷和丁烷） 的命运，人们所做的研究工作相对来说似乎非常少。现在，研究人员从墨西哥湾 和加利福尼亚湾烃类渗出区收集到的沉积物中获得了能够在与天然气层中相似的 缺氧条件下利用丙烷和丁烷的微生物培养。这些从生物化学角度来看不同寻常的 细菌，可能是造成人们在海洋渗出气和其他含气层的气体中所观测到的变化的原 因。（Letter p. 898） “穴居人”活动范围被向东延伸了数千公里（Neanderthals go east） Neanderthals in central Asia and Siberia “穴居人”（Neanderthals）的经典形象（结实、脑袋长、头骨特征显著）在距 今大约40万年前出现，而在距今大约3万年前从所谓的“人族”中消失。然而， 确定散碎化石的精确身分却很困难。Krause等人利用线粒体DNA序列解决了这一 问题。这些序列证实，上个世纪30年代在乌兹别克斯坦出土的一个小孩骨架便来 自“穴居人”，而且表明来自更靠东的西伯利亚阿尔泰地区的化石也是“穴居 人”的。这一结果将“穴居人”的活动范围比以前的假设向东延伸了2,000公 里。（Letter p. 902） 人类在海边生活的最早证据（Life was a beach） Early human use of marine resources and pigment in South Africa during the Middle Pleistocene 曾经有人提出，智人（Homo sapiens）出现之后所做的第一件事情是到海滩去。 这一观点因在南非Pinnacle Point附近一个海蚀洞中的中更新世地层中获得的一 系列发现而得到戏剧化的验证。这些发现表明，在距今大约164,000年前，当地 住民所吃的东西包括甲壳类，这是关于人类开发滩涂资源的最早证据， 比以前 的证据早了大约4万年。还有证据表明，他们曾用色素如红赭石等作为某种象 征。当时世界正经历一次冷暖变化，非洲基本上是沙漠。也许正是这种环境压力 迫使少批游猎人群到海边去寻找新的食物来源和生活方式。（Letter p. 905; News & Views） 有抗病毒功能的细胞微RNA（Antiviral miRNA） Interferon modulation of cellular microRNAs as an antiviral mechanism 植物和无脊椎动物能在病毒感染中将RNA沉默用作一种保护机制。现在，细胞微 RNA也被发现在哺乳动物细胞中有一种抗病毒功能。β-干扰素参与人体细胞中若 干种细胞微RNA的调控，其中的8种对于抵抗丙肝病毒上的序列具有活性。此外， 细胞微RNA水平的调控还被发现能够显著改变β-干扰素的抗病毒效应，说明它们 是哺乳动物先天免疫反应体系的一个功能性构成部分。（Letter p. 919） ---------------------- NEWS AND VIEWS ---------------------- Palaeoanthropology: The coast in colour pp793 - 794 A South African cave overlooking the Indian Ocean was apparently a desirable residence for early humans. The site has provided rich evidence for the early use of colour and marine resources. Sally McBrearty and Chris Stringer doi:10.1038/449793a http://www.nature.com/nature/journal/v449/n7164/full/449793a.html Earth science: An Indian cheetah pp795 - 796 After the supercontinent of Gondwanaland broke up, the part that became India diverged especially swiftly from the other fragments. The explanation for this might lie in the loss of India's deep roots. R. Dietmar MA?ller doi:10.1038/449795a http://www.nature.com/nature/journal/v449/n7164/full/449795a.html String theory: Back to basics pp797 - 798 Long touted as a theory of everything, it seems that string theory may at last succeed as a theory of something very specific ― the interactions of particles under the strong nuclear force. Hermann Nicolai doi:10.1038/449797a http://www.nature.com/nature/journal/v449/n7164/full/449797a.html 50 & 100 Years Ago p797 doi:10.1038/449797b http://www.nature.com/nature/journal/v449/n7164/full/449797b.html Microbiology: Preparing the shot pp798 - 799 Direct injection of proteins into host cells is one of the tricks bacteria use during infection. It seems that, to achieve this, the stomach pathogen Helicobacter pylori first grabs the cell by its surface receptors. Christof R. Hauck doi:10.1038/449798a http://www.nature.com/nature/journal/v449/n7164/full/449798a.html Astronomy: Black holes go extragalactic pp799 - 801 The mass of a black hole beyond our Galaxy has been calculated, thanks to the presence of an associated star. The hole is the weightiest yet, placing intriguing constraints on how this binary system developed. Tomasz Bulik doi:10.1038/449799a http://www.nature.com/nature/journal/v449/n7164/full/449799a.html ---------------------- INSIGHT ---------------------- INTRODUCTION Host-microbe interactions p803 Claudia Lupp doi:10.1038/449803a http://www.nature.com/nature/journal/v449/n7164/full/449803a.html FEATURE The Human Microbiome Project pp804 - 810 Peter J. Turnbaugh et al. doi:10.1038/nature06244 Abstract: http://www.nature.com/nature/journal/v449/n7164/abs/nature06244.html Article: http://www.nature.com/nature/journal/v449/n7164/full/nature06244.html REVIEW ARTICLE An ecological and evolutionary perspective on human-microbe mutualism and disease pp811 - 818 Les Dethlefsen, Margaret McFall-Ngai and David A. Relman doi:10.1038/nature06245 Abstract: http://www.nature.com/nature/journal/v449/n7164/abs/nature06245.html Article: http://www.nature.com/nature/journal/v449/n7164/full/nature06245.html Recognition of microorganisms and activation of the immune response pp819 - 826 Ruslan Medzhitov doi:10.1038/nature06246 Abstract: http://www.nature.com/nature/journal/v449/n7164/abs/nature06246.html Article: http://www.nature.com/nature/journal/v449/n7164/full/nature06246.html Manipulation of host-cell pathways by bacterial pathogens pp827 - 834 Amit P. Bhavsar, Julian A. Guttman and B. Brett Finlay doi:10.1038/nature06247 Abstract: http://www.nature.com/nature/journal/v449/n7164/abs/nature06247.html Article: http://www.nature.com/nature/journal/v449/n7164/full/nature06247.html Bacterial pathogenomics pp835 - 842 Mark J. Pallen and Brendan W. Wren doi:10.1038/nature06248 Abstract: http://www.nature.com/nature/journal/v449/n7164/abs/nature06248.html Article: http://www.nature.com/nature/journal/v449/n7164/full/nature06248.html ---------------------- HYPOTHESIS ---------------------- The equilibria that allow bacterial persistence in human hosts pp843 - 849 Martin J. Blaser and Denise Kirschner doi:10.1038/nature06198 Abstract: http://www.nature.com/nature/journal/v449/n7164/abs/nature06198.html Article: http://www.nature.com/nature/journal/v449/n7164/full/nature06198.html ---------------------- ARTICLES ---------------------- A second generation human haplotype map of over 3.1 million SNPs pp851 - 861 A consortium reports the tripling of the number of genetic markers in Phase II of the International HapMap Project. This map of human genetic variation will continue to revolutionize discovery of susceptibility loci in common genetic diseases, and study of genes under selection in humans. doi:10.1038/nature06258 Abstract: http://www.nature.com/nature/journal/v449/n7164/abs/nature06258.html Article: http://www.nature.com/nature/journal/v449/n7164/full/nature06258.html Helicobacter exploits integrin for type IV secretion and kinase activation pp862 - 866 Integrins are cell adhesion receptors involved in a variety of signalling processes and are targeted by a number of bacterial and viral pathogens for adhesion or invasion. The gastric pathogen Helicobacter pylori's pilus protein CagL interacts with integrin, which subsequently triggers translocation and phoshorylation of the bacterial effector CagA. Terry Kwok et al. doi:10.1038/nature06187 Abstract: http://www.nature.com/nature/journal/v449/n7164/abs/nature06187.html Article: http://www.nature.com/nature/journal/v449/n7164/full/nature06187.html Protein-based peptide-bond formation by aminoacyl-tRNA protein transferase pp867 - 871 Some proteins are degraded by a process called the N-end rule, in which a non-templated amino acid is added to the amino terminus as a marker for degradation. A set of crystal structures of the enzyme that promotes transfer of the amino acid along with the charged donor tRNA is solved in the presence or absence of target peptide. The results reveal that peptide bond formation occurs differently than on the ribosome. Kazunori Watanabe et al. doi:10.1038/nature06167 Abstract: http://www.nature.com/nature/journal/v449/n7164/abs/nature06167.html Article: http://www.nature.com/nature/journal/v449/n7164/full/nature06167.html ---------------------- LETTERS ---------------------- A 15.65-solar-mass black hole in an eclipsing binary in the nearby spiral galaxy M 33 pp872 - 875 Models of stellar evolution have difficulty producing black holes in close binaries with masses ten times that of the sun, which is consistent with the fact that the most massive stellar black holes known so far all have masses within one standard deviation of that. This paper report a mass of 15.65 A±1.45 times that of the sun for the black hole in the recently discovered system M 33 X-7, which is located in the nearby galaxy Messier 33. Jerome A. Orosz et al. doi:10.1038/nature06218 Abstract: http://www.nature.com/nature/journal/v449/n7164/abs/nature06218.html Article: http://www.nature.com/nature/journal/v449/n7164/full/nature06218.html Nature of the superconductor-insulator transition in disordered superconductors pp876 - 880 As a superconducting thin film is made more disordered, or subject to an increasing magnetic field, a point is reached when the material undergoes a transition from a superconducting to an insulating state. Numerical simulations have been used to shed light on the nature of this transition, or, as it turns out, two types of transition. Yonatan Dubi, Yigal Meir and Yshai Avishai doi:10.1038/nature06180 Abstract: http://www.nature.com/nature/journal/v449/n7164/abs/nature06180.html Article: http://www.nature.com/nature/journal/v449/n7164/full/nature06180.html Nucleation and growth mechanism of ferroelectric domain-wall motion pp881 - 884 The polarization of a ferroelectric material by an electric field can be used as the basis of a memory device. Recording a piece of information in this way involves increasing the size of a region with one polarity at the expense of those having the opposite polarity, and hence the movement of the domain walls separating these regions. This paper reports multi-scale simulations that reproduce the domain growth rates observed experimentally, and suggest a nucleation process that is energetically realistic. Young-Han Shin, Ilya Grinberg, I-Wei Chen and Andrew M. Rappe doi:10.1038/nature06165 Abstract: http://www.nature.com/nature/journal/v449/n7164/abs/nature06165.html Article: http://www.nature.com/nature/journal/v449/n7164/full/nature06165.html Coaxial silicon nanowires as solar cells and nanoelectronic power sources pp885 - 889 Solar cells based on such coaxial nanowires made from silicon have been fabricated. Under a standard one solar equivalent (1-sun) illumination a maximum power output up to 200 pW per nanowire and an apparent energy conversion efficiency of up to 3.4% is achieved. Experiments demonstrate that such silicon nanowire photovoltaic elements can serve as robust power sources in nanoelectronic circuits. Bozhi Tian et al. doi:10.1038/nature06181 Abstract: http://www.nature.com/nature/journal/v449/n7164/abs/nature06181.html Article: http://www.nature.com/nature/journal/v449/n7164/full/nature06181.html Carbon dioxide release from the North Pacific abyss during the last deglaciation pp890 - 893 Geochemical records from ocean sediment cores are used to shed light on the composition and ventilation of water in the deep North Pacific during the Last Glacial Maximum. A poorly-ventilated water mass that was rich in respired carbon dioxide occupied the North Pacific abyss during the Last Glacial Maximum, and that ventilation of the abyss increased during deglaciation, releasing carbon dioxide into the atmosphere. Eric D. Galbraith et al. doi:10.1038/nature06227 Abstract: http://www.nature.com/nature/journal/v449/n7164/abs/nature06227.html Article: http://www.nature.com/nature/journal/v449/n7164/full/nature06227.html The rapid drift of the Indian tectonic plate pp894 - 897 Prakash Kumar et al. doi:10.1038/nature06214 Abstract: http://www.nature.com/nature/journal/v449/n7164/abs/nature06214.html Article: http://www.nature.com/nature/journal/v449/n7164/full/nature06214.html Anaerobic oxidation of short-chain hydrocarbons by marine sulphate-reducing bacteria pp898 - 901 Ethane, propane and butane are constituents of natural gas in anoxic marine sediments. The first microbial isolate belonging to the sulphate-reducing bacteria capable of anaerobically oxidizing short-chain non-methane hydrocarbons is described. Olaf Kniemeyer et al. doi:10.1038/nature06200 Abstract: http://www.nature.com/nature/journal/v449/n7164/abs/nature06200.html Article: http://www.nature.com/nature/journal/v449/n7164/full/nature06200.html Neanderthals in central Asia and Siberia pp902 - 904 Determining the precise identity or origin of fragmentary fossils can be difficult. Here, mitochondrial DNA sequences are used to confirm that the skeleton of a child recovered in Uzbekistan in the 1930s was of Neanderthal origin and that remains from the Altai region of Siberia, much further east, are also Neanderthal, extending the Neanderthal range 2,000 km further east than previously assumed. Johannes Krause et al. doi:10.1038/nature06193 Abstract: http://www.nature.com/nature/journal/v449/n7164/abs/nature06193.html Article: http://www.nature.com/nature/journal/v449/n7164/full/nature06193.html Early human use of marine resources and pigment in South Africa during the Middle Pleistocene pp905 - 908 Evidence of shellfish use and cultural practice (use of red ochre) by Homo sapiens from a sea-cave in South Africa around 164,000 years ago presents the earliest evidence for the exploitation of coastal resources by some 40,000 years. At that time Africa was mostly desert, possibly driving small bands of hunter-gatherers seawards in search of new food sources Curtis W. Marean et al. doi:10.1038/nature06204 Abstract: http://www.nature.com/nature/journal/v449/n7164/abs/nature06204.html Article: http://www.nature.com/nature/journal/v449/n7164/full/nature06204.html Turnover of sex chromosomes induced by sexual conflict pp909 - 912 The genetic sex determination system is a rapidly evolving feature of the genome in many species. The master sex-determining gene moves frequently between chromosomes in some taxa, whereas in others more than one pair of chromosomes determines sex. This paper shows that these evolutionary patterns can result from genes with antagonistic effects: they can hijack sex determination from one chromosome to another. G. S. van Doorn and M. Kirkpatrick doi:10.1038/nature06178 Abstract: http://www.nature.com/nature/journal/v449/n7164/abs/nature06178.html Article: http://www.nature.com/nature/journal/v449/n7164/full/nature06178.html Genome-wide detection and characterization of positive selection in human populations pp913 - 918 Sabeti et al. build on their This paper builds on previous work of detecting selection on human genes, using the many more markers available in the Phase II HapMap project. Three examples of apparent population-specific selection based on geographic area are described, and how these may relate to human biology is discussed. Pardis C. Sabeti et al. doi:10.1038/nature06250 Abstract: http://www.nature.com/nature/journal/v449/n7164/abs/nature06250.html Article: http://www.nature.com/nature/journal/v449/n7164/full/nature06250.html Interferon modulation of cellular microRNAs as an antiviral mechanism pp919 - 922 Plants and invertebrates can use RNA silencing as a protective mechanism in viral infection. Cellular microRNAs can have anti-viral activity also in mammalian cells, in this case by contributing to the antiviral effects of interferon beta against hepatitis C virus. Irene M. Pedersen et al. doi:10.1038/nature06205 Abstract: http://www.nature.com/nature/journal/v449/n7164/abs/nature06205.html Article: http://www.nature.com/nature/journal/v449/n7164/full/nature06205.html Architectural and mechanistic insights into an EHD ATPase involved in membrane remodelling pp923 - 927 Structural details of mouse EHD2 are provided along with in vitro and in vivo assays, showing how an EHD oligomer is formed and how perpendicular curvature stresses on a membrane surface can result in remodelling of membranes by EHD oligomeric rings. The functional implications of the EHD2 structure for understanding of membrane deformation are also discussed. Oliver Daumke et al. doi:10.1038/nature06173 Abstract: http://www.nature.com/nature/journal/v449/n7164/abs/nature06173.html Article: http://www.nature.com/nature/journal/v449/n7164/full/nature06173.html Arginine methylation at histone H3R2 controls deposition of H3K4 trimethylation pp928 - 932 Methylation of histone H3 on residue Lys4 (H3K4) contributes to transcription activation. Now it is shown that in budding yeast, an adjacent modification, methylated Arg2, can inhibit H3K4 methylation by preventing the binding of a methyl transferase complex. Antonis Kirmizis et al. doi:10.1038/nature06160 Abstract: http://www.nature.com/nature/journal/v449/n7164/abs/nature06160.html Article: http://www.nature.com/nature/journal/v449/n7164/full/nature06160.html Methylation of histone H3R2 by PRMT6 and H3K4 by an MLL complex are mutually exclusive pp933 - 937 The arginine methyltransferase PRMT6 is shown to methylate histone H3 on Arg2 in mammalian cells, and this modification is mutually antagonistic with methylation of Lys4 on H3 by the methyl transferase complex MLL. Ernesto Guccione et al. doi:10.1038/nature06166 Abstract: http://www.nature.com/nature/journal/v449/n7164/abs/nature06166.html Article: http://www.nature.com/nature/journal/v449/n7164/full/nature06166.html (责任编辑：泉水) |