This press release contains:
· Summaries of newsworthy papers:
Astronomy: Hot water around a carbon star
Neuroscience: New drug target for Alzheimer’s disease
Opinion: Questionable stewardship
Climate science: Clouds on the horizon for China's crops
Genetics: HapMap 3 is here
Electronics: A high-performance graphene transistor
Biological physics: Collective motion in a simple model system
And finally… The life and works of charitable bacteria
· Mention of papers to be published at the same time with the same embargo
· Geographical listing of authors
Editorial contacts: While the best contacts for stories will always be the authors themselves, in some cases the Nature editor who handled the paper will be available for comment if an author is unobtainable. Editors are contactable via Ruth Francis on +44 20 7843 4562. Feel free to get in touch with Nature's press contacts in London, Washington and Tokyo (as listed at the end of this release) with any general editorial inquiry.
Warning: This document, and the Nature papers to which it refers, may contain information that is price sensitive (as legally defined, for example, in the UK Criminal Justice Act 1993 Part V) with respect to publicly quoted companies. Anyone dealing in securities using information contained in this document or in advanced copies of Nature’s content may be guilty of insider trading under the US Securities Exchange Act of 1934.
The Nature journals press site is at http://press.nature.com
· PDFs for the Articles, Letters, Progress articles, Review articles, Insights and Brief Communications in this issue will be available on the Nature journals press site from 1400 London time / 0900 US Eastern Time on the Friday before publication.
· PDFs of News & Views, News Features, Correspondence and Commentaries will be available from 1400 London time / 0900 US Eastern Time on the Monday before publication
PICTURES: While we are happy for images from Nature to be reproduced for the purposes of contemporaneous news reporting, you must also seek permission from the copyright holder (if named) or author of the research paper in question (if not).
HYPE: We take great care not to hype the papers mentioned on our press releases, but are sometimes accused of doing so. If you ever consider that a story has been hyped, please do not hesitate to contact us at [email protected], citing the specific example.
PLEASE CITE NATURE AND OUR WEBSITE www.nature.com/nature AS THE SOURCE OF THE FOLLOWING ITEMS. IF PUBLISHING ONLINE, PLEASE CARRY A HYPERLINK TO http://www.nature.com/nature
[1] Astronomy: Hot water around a carbon star (pp 64-67; N&V)
Water vapour with a temperature of about 700 degrees Celsius has been detected in the spectrum of an ageing carbon-rich star. This surprising discovery, which indicates the presence of water close to the star, in the warm inner region of its gaseous envelope, highlights gaps in our understanding of the chemistry of highly evolved stars.
The carbon-rich giant star IRC+10216 has been puzzling astronomers since 2001, when water vapour was first detected in its circumstellar envelope. This discovery challenged the current understanding of stellar chemistry, because in a carbon-rich environment at thermodynamic equilibrium, no oxygen-rich molecules (except for carbon monoxide) are expected to be present. Several mechanisms were suggested for producing the water, including the vaporization of icy bodies in orbit around the star; but with only one spectral line detected, it was difficult to discriminate among the mechanisms.
Now, using the Herschel Space Observatory, Leen Decin and colleagues have detected dozens of water vapour lines in the spectrum of IRC+10216. As the authors report in this week’s Nature, some of the lines are produced by transitions from highly excited states, indicating a temperature of about 700 degrees Celsius. This means that water must be present in the warm sooty inner envelope — ruling out mechanisms, such as icy-body vaporization, that produce water only in the outer regions. One possible explanation may be the photochemical production of water by ultraviolet photons, if the star’s envelope has a clumpy structure that allows light to penetrate deep into the inner circumstellar regions.
Author contact:
Leen Decin (Katholieke Universiteit Leuven, Belgium)
Tel: +32 473 463135
E-mail: [email protected]
Bengt Gustafsson (Uppsala University, Sweden) N&V author
Tel: +46 18 471 5959
E-mail: [email protected]
[2] Neuroscience: New drug target for Alzheimer’s disease (pp 95-98; N&V)
Drugs that target a newly discovered brain protein may hold promise for treating Alzheimer’s disease, a Nature paper suggests.
The enzyme, called gamma-secretase activating protein (gSAP), selectively increases the production of amyloid beta, which forms the characteristic plaques found in the brains of people with Alzheimer’s. Knocking down the protein in a mouse model of Alzheimer’s disease reduces levels of amyloid beta and plaque development, Paul Greengard and colleagues show.
Critically, gSAP yields its effects by interacting with both gamma-secretase and its substrate, and does not interact with other gamma-secretase-related molecules such as Notch, which is needed for normal biological functioning. In theory this gives gSAP-blocking drugs the edge over previous, less specific gamma-secretase inhibitors.
Author contact:
Paul Greengard (Rockefeller University, New York, NY, USA)
Tel: +1 212 327 8780
E-mail: [email protected]
Peter St George-Hyslop (University of Toronto, Canada) N&V author
Tel: +1 416 978 7460
E-mail: [email protected]
Opinion: Questionable stewardship? (pp 28-29)
The Marine Stewardship Council (MSC), the world’s most prominent organization for certifying sustainable fisheries, is failing to live up to its promise, write six fisheries experts in an Opinion piece in this week’s Nature.
Although the MSC started with good intentions and good practices, the authors say, scores of scientists and many conservation groups are increasingly protesting various MSC procedures or certifications. There have been complaints, for example, about the MSC’s decision to certify a krill fishery in May this year. Krill are at the base of the Antarctic food chain, are undergoing a long-term decline and are under threat from climate change, the authors note. Worse, krill is caught largely to feed farmed fish, pigs and chicken, which is not a sustainable practice, they argue. There have also been protests about a proposal — currently under review, with a decision expected in September — to certify an Antarctic toothfish (Dissostichus mawsoni) fishery as sustainable. Many scientists argue that too little is known about this fish to justify such a move.
The authors argue that the MSC should tighten or change their rules, to exclude fisheries that are being heavily depleted, fisheries that are reliant on high-impact methods such as bottom trawling, fisheries that feed farming rather than people and fisheries that might be heavily affected by climate change. They also note that the current certification system might create a financial conflict of interest, because certifiers that leniently interpret existing criteria might expect to receive more work and profit from ongoing annual audits.
Author contact:
Jennifer Jacquet (University of British Columbia, Vancouver, Canada)
E-mail: [email protected]
[3] Climate science: Clouds on the horizon for China's crops (pp 43-51)
China is a major emitter of greenhouse gases, and its impact on climate change is a growing concern. In a Review in this week's Nature, Shilong Piao and colleagues highlight the difficulty in firmly establishing the impacts of climate change on China’s agricultural and water resources.
China has to feed 22% of the world's population with only 7% of the world's arable farmland. But the country's water resources are unevenly distributed between the south, where water is abundant, and the drier north. Recent changes in China’s climate have varied regionally too: northern China is warming faster and becoming drier than the southern part of the country, but precipitation changes are mostly within normal variability. The frequency of days with rain has decreased overall, but the trends have been most common in the south.
The effects that China’s changing climate will have on water resources and crop production remain uncertain. The authors suggest that, at best, we may expect crop production to remain constant, whereas the worst-case scenario could see crop yield decline by 20%, which could have a serious impact on China’s booming economic growth. To better predict and prepare for the future, improvements are required in regional climate models, especially for precipitation, and in our knowledge of crop responses to multiple stressors.
Author contact:
Shilong Piao (Peking University, Beijing, China)
Tel: +86 10 6275 1179
E-mail: [email protected]
[4] Genetics: HapMap 3 is here (pp 52-58)
A new, improved map of human genetic variation should boost research into the causes of disease in diverse human populations. ‘HapMap 3’ is revealed in this week’s Nature.
Understanding the differences in our genetic make-up is central to deciphering the roots of disease and, although collaborative efforts have collectively identified around 10 million common DNA variants, they come from a limited set of DNA samples. HapMap 3 extends the sampling to 1,184 individuals, integrating common and rare genetic differences from 11 global populations and providing insights into population-specific differences among variants.
It is hoped that this expanded public resource, documented by Richard Gibbs and The International HapMap 3 Consortium, will serve as a step towards a high-resolution map of the landscape of human genetic variation.
Author contact:
Richard Gibbs (Baylor College of Medicine, Houston, TX, USA)
Tel: +1 713 798 6539;
E-mail: [email protected]
[5] Electronics: A high-performance graphene transistor (AOP)
DOI: 10.1038/nature09405
***This paper will be published electronically on Nature's website on 01 September at 1800 London time / 1300 US Eastern Time (which is also when the embargo lifts) as part of our AOP (ahead of print) programme. Although we have included it on this release to avoid multiple mailings it will not appear in print on 02 September, but at a later date. ***
A significant step towards post-silicon electronics is reported in this week’s Nature. Xiangfeng Duan and colleagues describe a new way to fabricate transistors based on the material graphene, which preserves its favourable electronic properties and enables high device performance.
The atomically thin carbon sheets known as graphene have attracted considerable interest as a possible replacement for silicon in ultrahigh-speed, radio-frequency electronics. But the fabrication processes used in silicon technology are not readily applicable to graphene, because they can introduce significant defects into the graphene lattice, thus compromising device performance.
Duan and colleagues circumvent this problem by using an alumina-coated conducting nanowire as the ‘gate’ for their graphene transistor. The nanowire is placed on the graphene using a physical transfer process that does not disturb the graphene lattice. The transistor’s ‘source’ and ‘drain’ contacts are then fabricated by a self-aligning process (using the nanowire as a mask) that ensures precise positioning — thus minimizing the resistance that often degrades the performance of nanometre-scale devices. The result is a graphene transistor that is comparable in speed to the best existing devices of similar size.
Author contact:
Xiangfeng Duan (University of California, Los Angeles, CA, USA)
Tel: +1 310 267 4947
E-mail: [email protected]
[6] Biological physics: Collective motion in a simple model system (pp 73-77; N&V)
A model experimental system for the study of self-organized collective motion is described in this week’s Nature. The system — which comprises filaments of the protein actin propelled by motor proteins immobilized on a surface — is simple, yet displays a rich repertoire of behaviours that promise to provide new insight into the emergence of large-scale order from local interactions.
Flocks of birds, colonies of microorganisms and the dynamic scaffolding of cells (the cytoskeleton) are all systems in which orientable, self-propelled units interact to produce coherent motion at a larger scale. Similarities in the behaviour of such ‘active systems’ suggest that underlying universal principles are at work, but there is as yet no thorough understanding of how ordered structures emerge. One obstacle has been a lack of simple, controllable experimental systems in which theoretical ideas can be tested.
Andreas Bausch and colleagues now provide such a system, and show how it can be used to understand the links between local interactions and collective motion. When the concentration of actin filaments exceeds a critical value, they self-organize to form coherently moving structures, which can be much larger than the filaments themselves. Combining the observations with computer simulations, the authors identify mechanisms underlying the formation and decay of the observed patterns. The system’s simplicity, controllability and scope for extension to more complex interactions should make it a valuable tool for the further study of active systems.
Author contact:
Andreas Bausch (Technical University Munich, Germany)
Tel: +49 89 289 12480
E-mail: [email protected]
Jean-François Joanny (Institut Curie, Paris, France) N&V author
Tel: +33 1 56 24 67 54
E-mail: [email protected]
[7] And finally… The life and works of charitable bacteria (pp 82-85; N&V)
Antibiotic resistance can spread through a bacterial population thanks to the charitable actions of a benevolent minority, a Nature study reveals.
Faced with increasing antibiotic levels, highly resistant bacterial mutants provide protection to the non-resistant majority by producing the signalling molecule indole, James Collins and colleagues report. Indole helps turn on drug efflux pumps and oxidative stress protective mechanisms in the non-resistant bacteria, but its production comes at a cost to the altruist.
The phenomenon is akin to kin selection, with charitable individuals incurring a personal cost in order to boost the overall fitness of the population. Efforts to monitor and combat antibiotic resistance are complicated by these bet-hedging survival strategies and other forms of bacterial cooperation. A deeper understanding of the signalling molecules involved should therefore aid the rational design of more effective antibiotics.
Author contact:
James Collins (Boston University, MA, USA)
Tel: +1 617 353 0390
E-mail: [email protected]
Alexander van Oudenaarden (Massachusetts Institute of Technology, Cambridge, MA, USA) N&V author
Tel: +1 617 253 4446
E-mail: [email protected]
ALSO IN THIS ISSUE…
[8] Olivine water contents in the continental lithosphere and the longevity of cratons (pp 78-81)
[9] Genome-wide measurement of RNA secondary structure in yeast (pp 103-107)
[10] Neurotrophin receptors TrkA and TrkC cause neuronal death whereas TrkB does not (pp 59-63)
[11] A spindle-independent cleavage furrow positioning pathway (pp 91-94)
[12] Mechanism of the ATP-dependent DNA end-resection machinery from Saccharomyces cerevisiae (pp 108-111)
[13] DNA end resection by Dna2–Sgs1–RPA and its stimulation by Top3–Rmi1 and Mre11–Rad50–Xrs2 (pp 112-116)
ADVANCE ONLINE PUBLICATION
***This paper will be published electronically on Nature's website on 01 September at 1800 London time / 1300 US Eastern Time (which is also when the embargo lifts) as part of our AOP (ahead of print) programme. Although we have included it on this release to avoid multiple mailings it will not appear in print on 02 September, but at a later date. ***
[1] Selectivity mechanism of the nuclear pore complex characterized by single cargo tracking
DOI: 10.1038/nature09285
GEOGRAPHICAL LISTING OF AUTHORS…
The following list of places refers to the whereabouts of authors on the papers numbered in this release. For example, London: 4 - this means that on paper number four, there will be at least one author affiliated to an institute or company in London. The listing may be for an author's main affiliation, or for a place where they are working temporarily. Please see the PDF of the paper for full details.
AUSTRALIA
Canberra: 4
AUSTRIA
Vienna: 1
BELGIUM
Brussels: 1
Leuven: 1
CANADA
Lethbridge: 1
CHINA
Beijing: 3, 4
FRANCE
Gif-sur-Yvette: 3
Grenoble: 1
Meudon: 1
St Martin d’Héres: 1
GERMANY
Frankfurt: 8
Garching: 1, 6
Munich: 6
Neuherberg: 10
ISRAEL
Rehovot: 9
ITALY
Florence: 4
JAPAN
Hokkaido: 4
KENYA
Eldoret: 4
NETHERLANDS
Amsterdam: 1
SPAIN
Madrid: 1, 10
SWITZERLAND
Basel: 10
Geneva: 4
UNITED KINGDOM
Bristol: 3
Cambridge: 4
Cardiff: 1
Didcot: 1
Dorking: 1
Edinburgh: 1
London: 1
Oxford: 4
UNITED STATES OF AMERICA
Arizona
Tempe: 8
California
Berkeley: 14
Davis: 13
Foster City: 9
Hayward: 14
Los Angeles: 5
Pasadena: 13
San Francisco: 4
Stanford: 9
Connecticut
New Haven: 2, 12
Maryland
Baltimore: 4
Bethesda: 4, 14
Massachusetts
Boston: 4, 7
Cambridge: 4, 9
New York
Ithaca: 4
New York: 2
North Carolina
Durham: 4
Ohio
Cleveland: 4
Oklahoma
Norman: 4
Oregon
Eugene: 11
Texas
Houston: 4, 8, 12
PRESS CONTACTS…
From North America and Canada
Neda Afsarmanesh, Nature New York
Tel: +1 212 726 9231
E-mail: [email protected]
From Japan, Korea, China, Singapore and Taiwan
Mika Nakano, Nature Tokyo
Tel: +81 3 3267 8751
E-mail: [email protected]
From the UK
Rebecca Walton, Nature, London
Tel: +44 20 7843 4502
E-mail: [email protected]
About Nature Publishing Group (NPG):
Nature Publishing Group (NPG) is a publisher of high impact scientific and medical information in print and online. NPG publishes journals, online databases and services across the life, physical, chemical and applied sciences and clinical medicine.
Focusing on the needs of scientists, Nature (founded in 1869) is the leading weekly, international scientific journal. In addition, for this audience, NPG publishes a range of Nature research journals and Nature Reviews journals, plus a range of prestigious academic journals including society-owned publications. Online, nature.com provides over 5 million visitors per month with access to NPG publications and online databases and services, including Nature News and NatureJobs plus access to Nature Network and Nature Education’s Scitable.com.
Scientific American is at the heart of NPG’s newly-formed consumer media division, meeting the needs of the general public. Founded in 1845, Scientific American is the oldest continuously published magazine in the US and the leading authoritative publication for science in the general media. Together with scientificamerican.com and 15 local language editions around the world it reaches over 3 million consumers and scientists. Other titles include Scientific American Mind and Spektrum der Wissenschaft in Germany.
Throughout all its businesses NPG is dedicated to serving the scientific and medical communities and the wider scientifically interested general public. Part of Macmillan Publishers Limited, NPG is a global company with principal offices in London, New York and Tokyo, and offices in cities worldwide including Boston, Buenos Aires, Delhi, Hong Kong, Madrid, Barcelona, Munich, Heidelberg, Basingstoke, Melbourne, Paris, San Francisco, Seoul and Washington DC. For more information, please go to www.nature.com.
