This press release is copyright Nature.
VOL.440 NO.7082 DATED 16 MARCH 2006
This press release contains:
* Summaries of newsworthy papers:
* Astronomy: The Milky Way's own 'DNA' nebula
* Nanotechnology: Origami with DNA
* Brain: Early sign of Alzheimer's
* Quantum physics: Three's company, but don't hold hands
* Pharmacology: Missing targets for new antibiotics
* Palaeontology: Dinosaur locomotion - scientists at the wheel
* 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.
 Astronomy: The Milky Way's own 'DNA' nebula (pp 308-310)
An infrared nebula shaped like the double helix of DNA has been observed near the centre of the Milky Way, reports a paper in this week's Nature. While studying the magnetic field of the Galactic Centre, Mark Morris and colleagues observed the intertwined double helix nebula using a specialized camera on the Spitzer Space Telescope to observe thermal dust emission. The authors deduce from their observations that the double helix nebulais rotating with its axis positioned perpendicular to the Galactic plane. The magnetic field of the Galactic Centre is an interesting area of study because it could affect the orbits of molecular clouds, inhibit star formation and funnel cosmic rays away from the centre.
Mark Morris (University of California, Los Angeles, CA, USA)
Tel: +1 310 825 3320; E-mail: [email protected]
 Nanotechnology: Origami with DNA (pp 297-302; N&V)
A tiny map of the Americas is unveiled in this week's Nature. Two things are remarkable about its depiction of the continents in the standard Mercator projection. First, the scale. Maps in your atlas are typically drawn on scales of around 1:100 million, but this one is at 1:200 trillion. It is just a few hundred nanometres from east to west, smaller than a typical bacterium. Second, the nano-map is made from DNA. Paul Rothemund explains how to design and build structures, by making DNA molecules fold up into just about any two-dimensional nanoscale pattern imaginable. As well as his nano-Americas, Rothemund reveals DNA 'tiles' shaped like stars, smiley faces and flowers, and sheets bearing the letters 'DNA' and a simple image of the famous double-helix structure. Constructing nanoscale objects using DNA is nothing new, but Rothemund has taken it to another level - in terms of both the complexity of the structures he has produced, and the simplicity with which they are formed. As in earlier work, the new strategy exploits the fact that the chemical structures of DNA strands are programmed to selectively 'stick' only to strands with a complementary structure. This allows DNA strands to be designed so that they assemble spontaneously into complex shapes. But rather than rely on precisely designed and complementary long strands, Rothemund introduces what he calls DNA origami: short DNA strands are used to 'staple' a very long strand into any flat shape, including shapes with internal holes. The author says that there are limits to how big a structure can be made from a single strand; but he points out that very large structures can be
created by building separate fragments and then programming them to be 'stapled' together in the desired fashion.
Paul Rothemund (California Institute of Technology, Pasadena, CA, USA)
Tel: +1 626 390 0438; E-mail: [email protected]
Lloyd Smith (University of Wisconsin, Madison, WI, USA) N&V
Tel: +1 608 263 2594; E-mail: [email protected]
 Chemical biology: Illuminating the colour of fireflies (pp 372-376)
The brilliant yellow-green to yellow-orange chemical light that fireflies emit to communicate with one another has long been a source of fascination. Now a little more light has been shed on the 'bioluminescence' of these insects, according to new research published this week's Nature. Hiroaki Kato and colleagues have unravelled the mechanism by which firefly luciferase - the enzyme associated with the bioluminescence reaction - controls colour. This process is unrivalled in its efficiency in converting chemical energy into light; it is for this reason that luciferase is used by
many biologists as a 'readout' for their experiments. The authors have identified a specific conformational change in a key amino acid - an isoleucine residue - that controls the colour of the emitted light. It was already known that the colour of the emitted light changes if there is a single amino-acid substitution in luciferase, but the reason for that colour change had remained a mystery - until now. The mechanism they identified is likely to be common for other insect luciferases.
Hiroaki Kato (Kyoto University, Kyoto, Japan)
Tel: +81 75 753 4617; E-mail: [email protected]
 Brain: Early sign of Alzheimer's (pp 352-357; N&V)
Researchers in this week's Nature reveal what could be one of the earliest molecular seeds of Alzheimer's disease - an assembly of amyloid-b peptides that accumulates outside cells and affects memory. This finding could potentially be used to detect, and perhaps prevent, the disease long before more serious signs of memory loss arise. People at high risk of Alzheimer's disease show subtle memory problems and brain abnormalities several years before the onset of more serious clinical symptoms. Karen Ashe and her colleagues examined mice that have been genetically engineered to make a form of human amyloid-b precursor protein (APP) that is linked to Alzheimer's disease. Like humans, these mice show memory problems in middle age, before formation of the insoluble amyloid-b plaques classically associated with the disease. The researchers found that early memory deficits in these mice are caused by the accumulation of complexes of 12 amyloid-b peptides outside cells. When they injected these complexes into the brains of healthy rats, their memory was temporarily disrupted. The authors propose that these amyloid-b assemblies impair memory independently of plaques or neuronal death and that, under certain circumstances, they can trigger a series of events leading to Alzheimer's disease.
Karen Ashe (University of Minnesota, Minneapolis, MN, USA)
Tel: +1 612 626 0652; E-mail: [email protected]
Richard Morris (University of Edinburgh, Edinburgh, UK) N&V
Tel: +44 131 650 3518; E-mail: [email protected]
 Quantum physics: Three's company, but don't hold hands (pp 315-318; N&V)
Isaac Newton knew a thing or two about the way objects interact via physical forces, but even he realized that the problem is extremely complicated when there are more than two objects involved. Although Newton's theory of gravity accounts for how a single planet orbits a sun, the maths is impossible to solve exactly once you add another planet to the system. But Hanns-Christoph Nägerl and co-workers now show that there is at least one 'three-body problem' that can be well understood. They provided, in this week's Nature, the first experimental evidence for a prediction made in 1970 by the Russian physicist Victor Efimov of how three fundamental particles
called bosons will behave. Bosons are particles that have a particular quantum-mechanical property - a property shared by certain kinds of atom. Efimov predicted that three bosons could become loosely bound together in a so-called trimer, as if all three were held together in a bag, even if there were no bound states between just two of the particles. Nägerl and colleagues have now seen evidence for an Efimov trimer in a gas of caesium atoms cooled to within just a few hundred
billionths of a degree of absolute zero.
Hanns-Christoph Nägerl (Innsbruck University, Innsbruck, Austria)
Tel: +43 512 507 6316; E-mail: [email protected]
Brett Esry (Kansas State University, Manhattan, KS, USA) N&V
Tel: +1 785 532 1620; E-mail: [email protected]
 Pharmacology: Missing targets for new antibiotics (pp 303-307)
Metabolic enzymes are attractive targets for controlling infectious diseases, owing to their important role in microbial physiology and presence across many pathogens. Unfortunately, a study in this week's Nature reveals that there are few new metabolic targets left for antibiotics against Salmonella enterica. Dirk Bumann and colleagues obtained in vivo information about over 700 Salmonella enzymes, and identified 126 as essential for Salmonella virulence. The small number of metabolic pathways associated with these enzymes allowed the authors to conduct thorough experiments on all of the identified enzymes. Their results show that most of the pathways are already inhibited by existing antibiotics, or have been previously considered as potential targets. The authors conclude that there are few new metabolic targets for treatment
with broad-spectrum antibiotics, and highlight the need to focus research on previously known but unexploited targets.
Dirk Bumann (Hannover Medical School, Hannover, Germany)
Tel: +49 51 1532 9785; E-mail: [email protected]
 Palaeontology: Dinosaur locomotion - scientists at the wheel (N&V pp 292-294)
Scientific theory combines with Hollywood wizardry to bring dinosaurs to life in a News and Views feature in this week's Nature. In films, dinosaur locomotion is a result of clever software and the artistic interpretation of special effects departments. Now scientists are using improved software tools that have a firm grounding in physical principles, rather than artistic intuition, to test their own hypotheses on how dinosaurs walked the Earth. John Hutchinson and Stephen Gatesy present a Tyrannosaurus rex case study of how to use modern computer tools to reconstruct dinosaur movement.
They focus on the problems of determining the position of the limbs - its pose - at specific instants during a stride. By using combinations of motion-based and force-based criteria, the authors are able to filter out unlikely or impossible poses and establish a motion 'starting point'. The authors demonstrate the powers of computer simulation when combined with sound scientific theory and propose its application to factors, such as feeding, in other extinct animals. They highlight the need of palaeontologists to become better functional biologists to ensure that questions on popular science don't overtake basic evidence.
John Hutchinson (The Royal Veterinary College, Hatfield, UK)
Tel: +44 170 7666313; E-mail: [email protected]
ALSO IN THIS ISSUE...
 Discovery of two young brown dwarfs in an eclipsing binary system (pp 311-314)
 Visualizing dislocation nucleation by indenting colloidal crystals (pp 319-323)
 A mechanism to thin the continental lithosphere at magma-poor margins (pp 324-328)
 Multiple rounds of speciation associated with reciprocal gene loss in polyploid yeasts (pp 341-345)
 The finished DNA sequence of human chromosome 12 (pp 346-351)
 Stochastic protein expression in individual cells at the single molecule level (pp 358-362)
 The PerR transcription factor senses H2O2 by metal-catalysed histidine oxidation (pp 363-367)
 Crystal structure of the non-haem iron halogenase SyrB2 in syringomycin biosynthesis (pp 368-371)
 Getting hydrogen from solar photocatalysis (p 295)
ADVANCE ONLINE PUBLICATION
***This paper will be published electronically on Nature's website on X 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 X, but at a later date.***
 Shugoshin collaborates with protein phosphatase 2A to protect cohesin (DOI:10.1038/nature04663)
 Protein phosphatase 2A protects centromeric sister chromatid cohesion during meiosis I (DOI:10.1038/nature04664)
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.
Tokyo: 18, 19, 20
Los Angeles: 1, 2, 5, 9
Baltimore: 5, 10
Boston: 14, 17
Cambridge: 11, 15, 17
Ithaca: 2, 11, 16
For North America and Canada
Katie McGoldrick, Nature Washington
Tel: +1 202 737 2355; E-mail: [email protected]
For Japan, Korea, China, Singapore and Taiwan
Rinoko Asami, Nature Tokyo
Tel: +81 3 3267 8751; E-mail: [email protected]
For the UK/Europe/other countries not listed above
Ruth Francis, Nature London
Tel: +44 20 7843 4562; E-mail [email protected]
Zoe Corbyn, Nature London
Tel: +44 20 7843 4658; E-mail: [email protected]
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 [email protected] 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.