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Summaries of newsworthy papers from Nature. Vol.440 No.7083 Dated 23 March 2006

WWW.NATURE.COM/NATURE This press release is copyright Nature. VOL.440 NO.7083 DATED 23 MARCH 2006 This press release contains: * Summaries of newsworthy papers: * Conservation biology: Protected areas will not be enough to save Amazon * Agriculture: Rice pathogen scrutinized * Brain: Alzheimer's protein player exposed * Photonics: Squeezing light onto chips * Genetics: Down's syndrome * Climate: Antarctic ice core secrets * And finally...Plant promiscuity over-hyped * 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 press@nature.com <mailto:press@nature.com>, 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 [2] Conservation biology: Protected areas will not be enough to save Amazon (pp 520-523) Public wildlife reserves will not be enough to prevent the Brazilian Amazon from excessive deforestation, according to new conservation predictions. Without measures that also prevent the destruction of tropical rainforest on private land, about 40% of the Amazonian forest will be lost by 2050. Cattle ranching and soy production are boom industries that threaten to destroy much of Brazil's natural forest, say Britaldo Silveira Soares-Filho and colleagues in this week's Nature. They argue that, in addition to the establishment of publicly protected parks, farmers should be forced to meet guidelines certifying that they are managing their land in a sustainable way. Failure to do so would deny them access to lucrative international markets for their produce. The authors add that without such a strategy, conservation prospects are bleak. They used a computer model to predict future trends under a range of different conservation practices. If deforestation is allowed to continue unchecked, eight of the Amazon River's twelve major watersheds will lose more than half of their forest cover, and almost 100 of the region's native mammal species will lose over 50% of their habitat. CONTACT Britaldo Soares-Filho (Universidade Federal de Minas Gerais, Minas Gerais, Brazil) Tel: +55 313 499 5417; E-mail: britaldo@csr.ufmg.br [3] Agriculture: Rice pathogen scrutinized (pp 535-539) In this week's Nature, Nicholas Talbot and his colleagues reveal how the rice blast fungus Magnaporthe grisea, a major pathogen of cultivated rice and a threat to food security, invades the rice plant. From the genetic sequence data of this fungus, it seems that secreted peptides might underlie its pathogenicity. The Talbot team show that a protein in the fungi's protein-processing Golgi apparatus called MgAPT2 is necessary for secretion. The fungus uses small cellular sacs derived from the Golgi apparatus to transport virulent fungal peptides to the exterior of the plant cell. These peptides then help the fungus to gain entry into the plant cells so that it can spread through the plant tissue. MgAPT2 is also required in order for plant cells to launch a defensive response. CONTACT Nicholas Talbot (University of Exeter, Exeter, UK) Tel: + 44 1392 264 673; E-mail: n.j.talbot@exeter.ac.uk [4] Brain: Alzheimer's protein player exposed (pp 528-534) In this week's Nature, researchers reveal how an enzyme called Pin1 plays a part in the pathogenesis of Alzheimer's disease. Brain plaques, consisting of amyloid-beta peptides derived from amyloid precursor protein (APP), are one hallmark of Alzheimer's disease. Kun Ping Lu and his colleagues present evidence that Pin1 regulates the processing of APP into toxic forms of amyloid- beta. The team show that Pin1 directly binds to a specific region in APP, boosts-by 1,000-fold-its conversion from one conformation to another, and seems to suppress the production of amyloid- beta 42, a particularly toxic form of amyloid- beta. Further studies on this conformational change may help clarify the molecular events leading to Alzheimer's, the authors say. CONTACT Kung Ping Lu (Harvard Medical School, Boston, MA, USA) Tel: +1 617 667 4143; E-mail: klu@bidmc.harvard.edu [5] Geology: The oldest evidence of methane makers (pp 516-519; N&V) Methanogenic microbes - methane-making micro-organisms - are thought to be among Earth's earliest life forms. Exactly when they first appeared, though, has always been uncertain. No one has been able to find direct geological evidence to support the hypothesis that they existed in the Archaean era, 3.8 to 2.5 billion years ago. But as reported in this week's Nature, Yuichiro Ueno and colleges have been busy. The Japanese researchers have found evidence of methane-bearing fluid inclusions in about 3.5-billion-year-old hydrothermal precipitates from the Pilbara craton in Western Australia. Their analyses - through carbon isotope composition - indicate the methane is of microbial origin. It is the oldest evidence of methanogen existence, pre-dating previous circumstantial geochemical evidence by about 700 million years. Microbial methane may have been important in regulating the climate on the Archaean Earth - potentially providing sufficient amounts of the greenhouse gas to mitigate the severely frozen conditions. CONTACT Yuichiro Ueno (Tokyo Institute of Technology, Yokohama, Japan) Tel: +81 45 924 5142; E-mail: yueno@depe.titech.ac.jp Don Canfield (Odense University, Odense, Denmark) Tel: +45 6550 2751; E-mail: dec@biology.sdu.dk [6] Photonics: Squeezing light onto chips (pp 508-511; N&V) A new family of devices for guiding and processing light signals in chip-based information technology is unveiled in this week's Nature by Sergey Bozhevolnyi and his colleagues. These miniaturized structures should help to overcome one of the main obstacles to making a compact 'photonic' technology comparable to that of microelectronics: the difficulty of manipulating light at very small scales. The key problem for 'microphotonics' is that light can only be transmitted properly through channels and holes that are wider than its wavelength. In today's fibre-optic telecommunications, wavelengths of about 1.5 micrometres (thousandths of a millimetre) are used, and that's a lot bigger than the channels along which electrons are guided on present-day silicon chips. But there is an alternative. Light waves can be used to excite collective, wavelike motions of electrons on the surface of metals, known as surface plasmons, which aren't restricted by this size limit. Bozhevolnyi and colleagues have shown previously that some of these plasmons can move, in the form of linked light and electron waves, along the bottom of V-shaped grooves in a metal that are much narrower than the wavelength of the light. They have now shown that such channels can be shaped so that they act as photonic devices for splitting and modifying light signals. The researchers have built a number of devices common in photonic technology, such as beam splitters, from these V-shaped channels, and shown that they work well for infrared light signals at the standard telecom wavelength. CONTACT Sergey Bozhevolnyi (Aalborg University, Aalborg East, Denmark) Tel: +45 9635 9222; E-mail: sergey@physics.aau.dk Francisco Garcia-Vidal (Universidad Autonoma de Madrid, Madrid, Spain) Tel: +34 914 978 515; E-mail: fj.garcia@uam.es <mailto:fj.garcia@uam.es> [7] Genetics: Down's syndrome (AOP) DOI: 10.1038/nature04678 ***This paper will be published electronically on Nature's website on 22 March 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 23 March, but at a later date.*** Down's syndrome is caused by having three (rather than two) copies of chromosome 21, but researchers know little about how a 1.5-fold increase in gene dosage on this chromosome triggers the various developmental problems associated with Down's syndrome. In a study published online by Nature, Gerald Crabtree and his colleagues make an important step towards answering that question. They show that two genes on chromosome 21, called DSCR1 and DYRK1A, work together to export from the cell nucleus - and reduce the activity of - a group of NFAT proteins that are critical for gene regulation during vertebrate growth and development. The authors found that mice with mutations in Nfat genes show many of the characteristics of Down's syndrome. NFAT proteins normally operate under a positive feedback loop, enhancing their own production. The researchers used mathematical modelling and studies of genetically engineered mice to show that a 1.5-fold increase in DSCR1 and DYRK1A gene dosage produces a disproportionately large reduction in NFAT activity. The feedback loop means that an initially small reduction in NFAT grows into a larger one, leading to decreased activation of NFAT target genes. CONTACT Gerald Crabtree (Stanford University School of Medicine, Stanford, CA, USA) Tel: +1 650 723 8391; E-mail: crabtree@stanford.edu [8] Molecular nanotechnology: Pedal power (pp 512-515) A set of molecular pedals that is powered by light and twists another molecule is reported in Nature this week by Takuzo Aida and co-workers. The molecule-sized device extends previous work on 'molecular machines' by showing how motion induced in one component can be transferred to another. Several research groups have shown that molecules that change shape when irradiated with light can be used to create molecular motors and other devices with moving parts. But in order to carry out useful tasks with such minuscule components, they will probably have to be linked up to other molecules, in much the same way as the mechanical motions of pistons in a car engine are transferred via crankshafts and gears to the wheels. Aida and colleagues have made a set of molecular pedals in which the absorption of light in one part of the molecule introduces a kink which drives the scissor-like swivelling of the pedal units around a kind of molecular ball-bearing. The challenge was then to transfer this swinging motion to another molecule, which they did by designing the pedals so that they trapped a 'guest' molecule between them. When the pedals swivelled, the guest molecule became twisted. The researchers suggest that sequences of such interlocking motions might allow remote control of molecular-scale processes. CONTACT Takuzo Aida (The University of Tokyo, School of Engineering, Tokyo, Japan) Tel: +81 3 5841 7251; E-mail: aida@macro.t.u-tokyo.ac.jp [9] Climate: Antarctic ice core secrets (pp 491-496) Chemical data from an ice core over three kilometres long provide an insight into past climatic conditions over eight glacial cycles, Eric Wolff and colleagues report in this week's Nature. Measurements from the Dome C Antarctic ice core constrained three environmental parameters over the past 740,000 years: winter sea-ice extent in the Indian Ocean, biogenic productivity in the Southern Ocean and climatic conditions in Patagonia. Their results suggest that over large timescales, sea-ice extent was closely tied to Antarctica temperature, and that sulphur compounds were not active in climate regulation. A change occurs in the amplitude of Antarctic temperature variations 440,000 years ago, but they discovered no associated changes in internal climatic feedbacks. CONTACT Eric Wolff (British Antarctic Survey, Cambridge, UK) Tel: + 44 1223 221491; E-mail: ewwo@bas.ac.uk [10] And finally...Plant promiscuity over-hyped (pp 524-527) 'Botanical horror stories' of cross-breeding in species, such as in dandelions, oaks and blackberries, are dismissed by a paper in this week's Nature, which proves that there are pure plant species lurking in the undergrowth. Previously, many botanists have believed that the concept of 'species' cannot be applied to plants, but this research demonstrates that they are more likely to produce reproductively independent lineages than animals. Rieseberg and colleagues set out to prove the 'innocence' of plants by looking at phenetic and/or crossing relationships in over 400 genera of plants and animals. The authors focus on a particular taxonomic problem - naming clusters of individuals that are phenotypically different, but genetically the same. They conclude that, contrary to popular belief, the clusters most likely arise from factors such as asexual reproduction and over-differentiation by taxonomists, rather than hybridization between distinct, sexual species. Although other factors, such as the development of seeds without fertilization, will continue to cause problems for botanists, they can now relax in the knowledge that there are discrete entities of plants that correspond to reproductively independent lineages existing at the species level. CONTACT Loren Rieseberg (Indiana University, Bloomington, IN, USA) Tel: +1 812 855 7614; E-mail: lriesebe@indiana.edu ALSO IN THIS ISSUE... [11] Human chromosome 11 DNA sequence and analysis including novel gene identification (pp 497-500) [12] Significant primordial star formation at redshifts z < 3-4 (pp 501-504) [13] A non-spherical core in the explosion of supernova SN 2004dj (pp 505-507) [14] An excitable gene regulatory circuit induces transient cellular differentiation (pp 545-550) [15] CHIP-mediated stress recovery by sequential ubiquitination of substrates and Hsp70 (pp 551-555) [16] RNA-mediated response to heat shock in mammalian cells (pp 556-560) [17] Endonucleolytic cleavage of eukaryotic mRNAs with stalls in translation elongation (pp 561-564; N&V) [18] Human role in Russian wild fires (pp 436-437) ADVANCE ONLINE PUBLICATION ***These papers will be published electronically on Nature's website on 22 March 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 them on this release to avoid multiple mailings they will not appear in print on 23 March, but at a later date.*** [19] Global landscape of protein complexes in the yeast Saccharomyces cerevisiae DOI: 10.1038/nature04670 [20] A voltage-gated proton-selective channel lacking the pore domain DOI: 10.1038/nature04700 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. BRAZIL Belo Horizonte: 2 Para: 2 CANADA Quebec: 11 Toronto: 19 CHINA Taiwan: 4 Shanghai: 4 DENMARK Aalberg Ost: 6 Copenhagen: 9 FRANCE St Martin d'He'res: 9 Strasbourg: 6 GERMANY Bremerhaven: 9 Heidelberg: 9 IRELAND Dublin: 19 ISRAEL Haifa: 16 ITALY Florence: 9 Ispra: 18 Venice: 9 JAPAN Ikoma: 19 Kawaguchi: 1, 5 Kyoto: 7 Sendai: 1 Tokyo: 11, 1, 8, 5 Tottori: 1 Yokohama: 5, 11 SOUTH KOREA Daejeon: 11 SPAIN Terrassa: 14 SWEDEN Stockholm: 9 SWITZERLAND Bern: 9 UNITED KINGDOM Cambridge: 9, 11 Exeter: 3 London: 11 UNITED STATES OF AMERICA Arizona Tuscan: 17 California Berkeley: 13 Pasadena: 13, 14 San Diego: 13 San Francisco: 19 Stanford: 7 Connecticut New Haven: 2, 19 Georgia Atlanta: 4 Indiana Bloomington: 10 Massachusetts Boston: 4, 20 Cambridge: 11, 19, 20 Woods Hole: 2 Missouri St Louis: 19 New York Greenvale: 16 New York: 12, 16 North Carolina Chapel Hill: 15 Ohio Cleveland: 16 Pennsylvania Philadelphia: 12 University Park: 13 Washington Seattle: 11 PRESS CONTACTS... For North America and Canada Katie McGoldrick, Nature Washington Tel: +1 202 737 2355; E-mail: k.mcgoldrick@naturedc.com For Japan, Korea, China, Singapore and Taiwan Rinoko Asami, Nature Tokyo Tel: +81 3 3267 8751; E-mail: r.asami@naturejpn.com For the UK/Europe/other countries not listed above Ruth Francis, Nature London Tel: +44 20 7843 4562; E-mail r.francis@nature.com Zoe Corbyn, Nature London Tel: +44 20 7843 4658; E-mail: z.corbyn@nature.com Victoria Picknell, Nature, London Tel: +44 20 7843 4502; E-mail: v.picknell@nature.com About Nature Publishing Group Nature Publishing Group (NPG) is a division of Macmillan Publishers Ltd, dedicated to serving the academic, professional scientific and medical communities. NPG's flagship title, Nature, is the world's most highly-cited weekly multidisciplinary journal and was first published in 1869. Other publications and services include Nature research journals, Nature Reviews, Nature Clinical Practice, a range of prestigious academic journals, including society-owned publications, news content from news@nature.com and scientific career information from Naturejobs. NPG is a global company, with headquarters in London and offices in New York, San Francisco, Washington DC, Boston, Tokyo, Paris, Munich, Hong Kong, Melbourne, Gurgaon and Basingstoke. For more information, please go to www.nature.com <http://www.nature.com>.

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