Table Of ContentVolume 436 Number 7052 pp753-888
In this issue (11 August 2005)
• Editorials • News and Views
• Research Highlights • Brief Communications
• News • Articles
• News Features • Letters
• Business • Naturejobs
• Correspondence • Futures
• Books and Arts
Editorials
Keeping religion out of science class p753
President Bush's endorsement of 'intelligent design' has sparked a national debate in which scientists
are well positioned to prevail.
Life in the old doc yet p753
The need to bring new blood into science shouldn't force out talented older researchers prematurely.
Tale of two tigers p754
Aspirant research hubs in southeast Asia have enjoyed contrasting fortunes.
Research Highlights
Research highlights p756
News
Medics braced for fresh superbug p758
Drug-resistant bacterium presents 'a real danger'.
Alison Abbott
Preparations get under way for tsunami warning system p759
International partners agree on first steps to prevent another disaster.
David Cyranoski
Scans provide picture of brain activity p759
Human study suggests fMRI can measure activity of brain cells.
Erika Check
Four years on, no transgenes found in Mexican maize p760
Corn found to be free of GM contamination.
Emma Marris
Scientists attack Bush over intelligent design p761
President's remarks spark angry response.
Virginia Gewin
Anti-terror study tracks gas dispersal p763
New York simulates chemical-weapon attack.
Tom Simonite
Japan accelerates global supercomputer war p763
Researchers make calculated bid to retake title for processor speed.
David Cyranoski
Sidelines p764
Europe set for tough debate on curbing aircraft emissions p764
European Commission looks to carbon trading to curb greenhouse-gas problem.
Jim Giles
News in brief p766
Correction p766
News Features
Singapore: An irresistible force p767
Singapore's impressive advances in biomedicine are driven by the energetic personality of Philip Yeo.
David Cyranoski meets a man who just can't stand still.
I
Cell biology: The secret life of sperm p770
Far from being mere DNA delivery boys, it's now becoming clear that sperm also ship a complex cargo of
RNA and proteins that may be crucial for an embryo's early development. Claire Ainsworth reports.
Science after retirement age: Breaking the age barrier p772
Many scientists continue to run productive and innovative research programmes well beyond typical
retirement age. But in many countries, tough retirement laws make staying in the lab a challenge. Laura
Bonetta reports.
Business
Ancient foil maker wraps up mobile-phone market p775
Centuries-old Japanese company carves out a fresh niche.
Ichiko Fuyuno
In brief p775
Correspondence
Harry Potter and the recessive allele p776
Jeffrey M. Craig, Renee Dow and MaryAnne Aitken
Tunnel vision all in the mind at Hothouse High p776
Samantha G. Zeitlin
Misconduct: acceptable practices differ by field p776
Frederick Grinnell
Cannabis on a downer p776
Martin J. Neumann
Books and Arts
The rovers' tale p777
How NASA scientists overcame the odds to find signs of water on Mars.
Gregory Benford reviews Roving Mars: Spirit, Opportunity, and the Exploration of the Red Planet by Steve
Squyres
Exhibition: Down and out p778
Collapse? At the Natural History Museum of Los Angeles County until 15 January 2006
http://www.nhm.org/exhibitions/collapse/index.html
Philip Campbell
Chemistry to die for p779
Roger P. Smith reviews The Elements of Murder: A History of Poison by John Emsley
Creatures and craters p779
News and Views
Neuroscience: Neurons and navigation p781
Where is the geometry of the environment represented in the brain? The entorhinal cortex, where neurons
fire repeatedly when an animal's position coincides with the vertices of a grid of triangles, looks like
a good bet.
György Buzsáki
Magnetospheric physics: Turbulence on a small scale p782
The four-spacecraft Cluster mission has identified small-scale vortices in Earth's magnetosphere. The
observation reveals processes that transfer energy and momentum from the solar wind to the magnetosphere.
Melvyn L. Goldstein
Plant biology: Engineered male sterility p783
The phenomenon of 'cytoplasmic male sterility' in plants has long been exploited to enhance the
productivity of certain crops. An innovative genetic-engineering system promises to widen applicability
of the approach.
Muhammad Sarwar Khan
50 & 100 years ago p785
Oceanography: A bigger nitrogen fix p786
Biologically useful nitrogen is delivered to the upper ocean from the depths by vertical transport
processes — or such was the received wisdom. In fact, bacteria that convert atmospheric nitrogen may
be just as crucial.
Nicolas Gruber
Cancer: Two in one p787
As cancer develops, at least two cell processes are disrupted — cell growth is promoted, and cell death
inhibited. It seems that mutated versions of the notorious cancer-promoting protein MYC can accomplish
both at once.
Anton Berns
II
Organic chemistry: Dotty solutions p789
Richard Webb
Mantle geochemistry: Big lessons from little droplets p789
How does Hawaii look deep below the surface? Like viewing an object at a different magnification, studies
of minuscule inclusions in volcanic rocks on the surface provide a fresh perspective on the question.
Claude Herzberg
Brief Communications
Phytochemistry: Structure of the blue cornflower pigment p791
Packaging red-rose anthocyanin as part of a 'superpigment' in another flower turns it brilliant blue.
Masaaki Shiono, Naohiro Matsugaki and Kosaku Takeda
Colorectal cancer: Mutations in a signalling pathway p792
D. Williams Parsons, Tian-Li Wang, Yardena Samuels, Alberto Bardelli, Jordan M. Cummins, Laura DeLong,
Natalie Silliman, Janine Ptak, Steve Szabo, James K. V. Willson, Sanford Markowitz, Kenneth W. Kinzler,
Bert Vogelstein, Christoph Lengauer and Victor E. Velculescu
Articles
The map-based sequence of the rice genome p793
International Rice Genome Sequencing Project *
Microstructure of a spatial map in the entorhinal cortex p801
Torkel Hafting, Marianne Fyhn, Sturla Molden, May-Britt Moser and Edvard I. Moser
Evasion of the p53 tumour surveillance network by tumour-derived MYC mutants p807
Michael T. Hemann, Anka Bric, Julie Teruya-Feldstein, Andreas Herbst, Jonas A. Nilsson, Carlos
Cordon-Cardo, John L. Cleveland, William P. Tansey and Scott W. Lowe
A contractile nuclear actin network drives chromosome congression in oocytes p812
Péter Lénárt, Christian P. Bacher, Nathalie Daigle, Arthur R. Hand, Roland Eils, Mark Terasaki and Jan
Ellenberg
Letters
A dark jet dominates the power output of the stellar black hole Cygnus X-1 p819
Elena Gallo, Rob Fender, Christian Kaiser, David Russell, Raffaella Morganti, Tom Oosterloo and Sebastian
Heinz
Discovery of the triple asteroidal system 87 Sylvia p822
Franck Marchis, Pascal Descamps, Daniel Hestroffer and Jérome Berthier
In situ multi-satellite detection of coherent vortices as a manifestation of Alfvénic
turbulence p825
David Sundkvist, Vladimir Krasnoselskikh, Padma K. Shukla, Andris Vaivads, Mats André, Stephan Buchert
and Henri Rème
Negative lattice expansion from the superconductivity−antiferromagnetism crossover in
ruthenium copper oxides p829
A. C. Mclaughlin, F. Sher and J. P. Attfield
A late Eemian aridity pulse in central Europe during the last glacial inception p833
F. Sirocko, K. Seelos, K. Schaber, B. Rein, F. Dreher, M. Diehl, R. Lehne, K. Jäger, M. Krbetschek and D.
Degering
The chemical structure of the Hawaiian mantle plume p837
Zhong-Yuan Ren, Stephanie Ingle, Eiichi Takahashi, Naoto Hirano and Takafumi Hirata
A wide depth distribution of seismic tremors along the northern Cascadia margin p841
Honn Kao, Shao-Ju Shan, Herb Dragert, Garry Rogers, John F. Cassidy and Kumar Ramachandran
The hangover gene defines a stress pathway required for ethanol tolerance development
p845
Henrike Scholz, Mirjam Franz and Ulrike Heberlein
Small vertical movement of a K+ channel voltage sensor measured with luminescence
energy transfer p848
David J. Posson, Pinghua Ge, Christopher Miller, Francisco Bezanilla and Paul R. Selvin
Gating charge displacement in voltage-gated ion channels involves limited
transmembrane movement p852
Baron Chanda, Osei Kwame Asamoah, Rikard Blunck, Benoît Roux and Francisco Bezanilla
Voltage-sensor activation with a tarantula toxin as cargo p857
L. Revell Phillips, Mirela Milescu, Yingying Li-Smerin, Joseph A. Mindell, Jae Il Kim and Kenton J. Swartz
III
Predictive models of molecular machines involved in Caenorhabditis elegans early
embryogenesis p861
Kristin C. Gunsalus, Hui Ge, Aaron J. Schetter, Debra S. Goldberg, Jing-Dong J. Han, Tong Hao, Gabriel
F. Berriz, Nicolas Bertin, Jerry Huang, Ling-Shiang Chuang, Ning Li, Ramamurthy Mani, Anthony A. Hyman,
Birte Sönnichsen, Christophe J. Echeverri, Frederick P. Roth, Marc Vidal and Fabio Piano
The ERECTA gene regulates plant transpiration efficiency in Arabidopsis p866
Josette Masle, Scott R. Gilmore and Graham D. Farquhar
Identification of JAK/STAT signalling components by genome-wide RNA interference p871
Patrick Müller, David Kuttenkeuler, Viola Gesellchen, Martin P. Zeidler and Michael Boutros
A high-resolution map of active promoters in the human genome p876
Tae Hoon Kim, Leah O. Barrera, Ming Zheng, Chunxu Qu, Michael A. Singer, Todd A. Richmond, Yingnian Wu,
Roland D. Green and Bing Ren
Corrigendum: EphB receptor activity suppresses colorectal cancer progression p881
Eduard Batlle, Julinor Bacani, Harry Begthel, Suzanne Jonkheer, Alexander Gregorieff, Maaike van de Born,
Núria Malats, Elena Sancho, Elles Boon, Tony Pawson, Steven Gallinger, Steven Pals and Hans Clevers
Erratum: An integrated view of the chemistry and mineralogy of martian soils p881
Albert S. Yen, Ralf Gellert, Christian Schröder, Richard V. Morris, James F. Bell, III, Amy T. Knudson,
Benton C. Clark, Douglas W. Ming, Joy A. Crisp, Raymond E. Arvidson, Diana Blaney, Johannes Brückner,
Philip R. Christensen, David J. DesMarais, Paulo A. de Souza, Jr, Thanasis E. Economou, Amitabha Ghosh,
Brian C. Hahn, Kenneth E. Herkenhoff, Larry A. Haskin, Joel A. Hurowitz, Bradley L. Joliff, Jeffrey R.
Johnson, Göstar Klingelhöfer, Morten Bo Madsen, Scott M. McLennan, Harry Y. McSween, Lutz Richter, Rudi
Rieder, Daniel Rodionov, Larry Soderblom, Steven W. Squyres, Nicholas J. Tosca, Alian Wang, Michael Wyatt
and Jutta Zipfel
Corrigendum: Similar response of labile and resistant soil organic matter pools to changes
in temperature p881
Changming Fang, Pete Smith, John B. Moncrieff and Jo U. Smith
Addendum: Evidence for magmatic evolution and diversity on Mars from infrared
observations p882
P. R. Christensen, H. Y. McSween, Jr, J. L. Bandfield, S. W. Ruff, A. D. Rogers, V. E. Hamilton, N. Gorelick,
M. B. Wyatt, B. M. Jakosky, H. H. Kieffer, M. C. Malin and J. E. Moersch
Naturejobs
Prospect
Searching questions p883
Search-engine companies raise the IT recruitment ante
Paul Smaglik
Region
Breaking open a closed system p884
Malaysia's research system is closed and isolated. What are scientists with a yen for rigorous research
to do? David Cyranoski finds out.
David Cyranoski
Errata
Correction p885
Career Views
Eric Staeva-Vieira, business analyst, Rodman and Renshaw, New York p886
A broad approach helps foster a business career
Recruiters & Academia p886
Teaching interdisciplinary courses proves to be an educational experience
Ariana Sutton-Grier and Melissa Kenney
Graduate Journal: A tale of a whale p886
Taking a break offers a fresh perspective
Jason Underwood
Futures
Prometheus unbound, at last p888
And not a moment too soon.
Kim Stanley Robinson
IV
11.8 Editorial 753 McP 9/8/05 2:42 PM Page 753
www.nature.com/nature Vol 436 |Issue no. 7052|11 August 2005
Keeping religion out of science class
President Bush’s endorsement of ‘intelligent design’ has sparked a national debate in which scientists are
well positioned to prevail.
C
omments made last week by President George W. Bush have design. Senator Rick Santorum (Republican, Pennsylvania), for
encouraged advocates of ‘intelligent design’, the idea that a example, is a Catholic and one of the most conservative members of
hidden hand must lie somewhere behind the evolution of the Senate, who faces a tough re-election battle next year. Just after
life. But the scientific community has responded energetically and Bush’s remarks, he forthrightly declared: “I’m not comfortable with
effectively to Bush’s statements. If researchers persevere, they can win intelligent design being taught in the science classroom.” Perhaps
this argument and keep religion out of the biology classroom. Santorum judges, wisely, that otherwise-conservative voters in
In an informal 90-minute interview with newspaper reporters the suburbs of Philadelphia and Pittsburgh would draw the line at
from his home state of Texas on 1 August, Bush talked at length backing a senator who wants to teach creationism to little Brad and
about everything from abortion to illegal immigration. When asked Britney in biology class.
about his view of intelligent design, the president was hesitant at first, Even hard-line creationists are aware of the political price of
re-iterating that, as governor of Texas, he had supported the right of appearing to be against science
“Part of the idea of
local school boards to choose what is taught in the classroom. Prod- in a nation that puts so much
intelligent design is
ded further to give an opinion, Bush said: “I’m not suggesting — stock in it. Part of the idea of
you’re asking me whether or not people ought to be exposed to intelligent design, of course, is subterfuge, an attempt to
different ideas, and the answer is yes.” subterfuge, an attempt to intro- introduce religion under
A great deal has been made of the president’s off-the-cuff endorse- duce religion under the guise
the guise of science.”
ment of intelligent design. But it is worth noting the hesitancy of his of science. In Kansas, after the
comments: he didn’t even mention intelligent design by name. Bush last row died down, a more conservative school board was elected
is a self-proclaimed evangelical Christian, and religious conserva- once again, and now may approve the inclusion of intelligent design
tives are often credited with helping him win last year’s election. But in its school curriculum. The progress of this effort — which scien-
he knows perfectly well that the introduction of religious ideas into tists have once again made a concerted effort to oppose — will be a
science class is a potentially explosive issue in US politics — and not bellwether for the rest of the country.
necessarily one that works in his favour. As we report on page 761, scientific leaders have responded effec-
The teaching of creationism in schools has been energetically tively to Bush’s ill-advised comments. Researchers from a range of
advocated in parts of the United States for decades, but it has rarely disciplines have spoken out vigorously, making it clear that the pres-
help politicians to win elections, even in the heartland. Take Kansas, ident’s apparent willingness to allow intelligent design into the class-
whose school board sought in 1999 to restrict the teaching of evolu- room is at odds with America’s pressing need to improve science
tion in public schools. A vocal outcry by scientists, business leaders education. They should continue to speak out in all available forums.
and others soon led to the electoral defeat of the board members in This argument has reverberated in US politics since at least 1925,
question and a repeal of the restrictions (see Nature406,552; 2000). when John Scopes, a high-school teacher in Dayton, Tennessee, was
Those Republicans who anticipate an encounter with the elec- convicted and fined for teaching evolution. The fight will go on —
torate are therefore cautious about the open embrace of intelligent but science and reason can ultimately win. ■
Life in the old doc yet
with decent pension provisions, to ensure dignity and leisure for the
old, while opening up job opportunities for the young. But there is a
big difference between being forced to work to avoid penury and
The need to bring new blood into science shouldn't
doing so because you love what you do. Most scientists’ work is far
force out talented older researchers prematurely. more than just a job — it is a vocation, pursued with a passion that
cannot be switched off overnight.
T
here is a common misperception that genius and exceptional And nor should it be. Carl Friedrich Gauss may have surprised his
scientific achievement are the preserve of the young. A News school-teacher at the age of seven when he worked out the factorial
Feature on page 772 of this issue shows the limitations of this of 100 in his head. But although the German mathematician made
view: some scientists are performing creative and groundbreaking many of his important discoveries before he was 20, he continued
work into their 70s and beyond. Yet many of them feel frustrated at to make progress in a wide variety of fields into his seventies. Charles
what they see as unjustified obstacles in their path — including, in Darwin wrote two of his best books, The Descent of Manand The
some countries, mandatory retirement for university professors. Expression of the Emotions in Man and Animals, in his sixties.
Mandatory retirement policies were generally introduced, along Science needs the energy and freshness of vision that youth can
753
© 2005 Nature PublishingGroup
©2005 Nature Publishing Group
11.8 Editorial 753 McP 9/8/05 2:42 PM Page 754
EDITORIALS NATURE|Vol 436|11 August 2005
bring, but it can also benefit from the perspective and experience stockmarket performance and inadequate provision for state pen-
of age. The qualitative research that has been done on the matter sions compound the problem. The subsequent discussion of higher
reinforces the common-sense view that groups of people from a retirement ages doesn’t thrill the public. But in science, it should
wide range of backgrounds are better at problem solving than are allow for a fuller consideration of measures that will tap the energy
homogeneous ones. Science needs to take steps to keep the door of older researchers who want to keep working.
open to exceptional older minds. It is time for policy-makers and university administrators to look
This must not, however, mean closing the door on younger more imaginatively at ways of structuring academic careers to intro-
researchers. In some countries — Germany and Japan spring to duce greater flexibility and alternative options. Just as science stands
mind — the security and immovability of a ruling caste of estab- to benefit from arrangements that will better accommodate women
lished senior professors sometimes does just that. Even in countries with children, or attract more interest from ethnic minorities, it can
with more flexible university systems, such as the United States, it benefit from active measures to help older researchers who still have
has never been tougher for young scientists to win faculty positions what it takes.
(see Nature422,354–355; 2003). Greater use of the ‘emeritus professor’ system, where researchers
At the same time, most countries face demographic and financial keep an association with an institution while drawing their salary
pressures that are forcing them to reconsider their general approach from their pension, can tap the brains of older specialists who are no
to mandatory retirement. Falling birth rates and higher life longer active in research. Research institutions and governments
expectancy mean that there will soon be far fewer working people to should also be searching for ways to accommodate those who want
support pensioners’ income, from public or private sources. Poor to remain active in research and have a contribution to make. ■
Tale of two tigers that favour native ethnic Malays, at the expensive of native ethnic
Chinese and Indians, as well as foreigners. It is understandable that
the Malaysian government wants to take measures to preserve the
Aspirant research hubs in southeast Asia have
opportunities for a group that makes up the majority of its popula-
enjoyed contrasting fortunes. tion, but which, by some measures, remains economically and
socially disadvantaged.
W
hen Malaysia and Singapore became politically distinct But accusations abound that the existing system is not sufficiently
entities in 1965, a yawning chasm soon developed meritocratic, and that personal connections often predominate in
between the two nations’ scientific performance — and decision-making, with regard to both hiring opportunities and the
it continues to grow. distribution of grants. Science also enjoys insufficient autonomy
Under the skilful tutelage of Philip Yeo, a businessman and former within the Malaysian government. And in instances such as the
engineer, Singapore is creating one of the world’s most dynamic BioValley project, investment has been showered on infrastructure,
research environments. The system built up by Yeo since he took rather than on people.
control of the nation’s science policy has given the country’s bio- Malaysia, of course, is not the only country in the region where
technology the promise of a bright future (see page 767). Despite research suffers from political mismanagement. China, Japan and
some questions about the commitment of Singapore’s government others are also prone to over-investment in facilities, as opposed to
to free expression, the island nation has succeeded in attracting both personnel; difficulties in the fair evaluation of grants; and problems
leading scientists and substantial business investment from abroad, in fully engaging with outside
“Singapore’s success
offering grants with few strings and a cosmopolitan research envi- scientists from neighbouring
ronment that is conducive to international collaboration. countries and further afield. could serve as a focal
Some concerns have been expressed about the reliance of Singa- Singapore’s success provides a point for more scientific
pore’s success on Yeo’s own energy and influence. But there is ample useful model in this regard. It collaboration in the region.”
evidence that he has put in place a meritocratic system that will could also serve as a focal point
comfortably outlive the oversight of one individual. In just two for more scientific collaboration in the region. East Asian countries
decades, Singapore has established itself as an important regional have never found it easy to work together. The Asia-Pacific Inter-
hub for biological research, with particular strengths in genomics national Molecular Biology Network (www.a-imbn.org), for example,
and cancer research. has sought for years to build a firmer foundation in the manner of the
Malaysia’s attempts to establish itself scientifically have been far European Molecular Biology Organization, which helped to build
less successful (see Nature436,620–621; 2005). The country has the European Molecular Biology Laboratory in Heidelberg, Germany.
sought in vain to establish a biotechnology industry, the most con- Singapore, with its recent track record of attracting top-notch
spicuous failure being the BioValley project near Kuala Lumpur. researchers, would be the ideal location for any such regional col-
New independent universities, emphasizing their dedication to laboration. It could also act as a bridge between researchers in China,
cutting-edge research, have been built after considerable political Japan and South Korea, where bitter rivalries have hamstrung such
negotiation, but they are struggling to establish themselves as inter- projects in the past. And it might enable Singapore to export some
nationally competitive. of the approaches which Yeo has so successfully championed in his
Part of Malaysia’s problem lies in educational and hiring policies own country. ■
754
© 2005 Nature PublishingGroup
©2005 Nature Publishing Group
11.8 Research Highlights NEW am 8/8/05 12:08 PM Page 756
Vol 436|11 August 2005
RESEARCH HIGHLIGHTS
V
GEOPHYSICS OLE
B
O
Up the Andes S. S
Geology33,617–620 and 621–624 (2005)
For more than 200 million years, the
South American plate slid westwards
over the Nazca plate without buckling.
Then, in the past 30 million years, the
spectacular plateau of the central
Andes was pushed up. What
changed? Using a computer model,
Stephan Sobolev and Andrey Babeyko,
both at Germany’s National Research
Centre for Geosciences in Potsdam,
have shown that the most important
factor was accelerated drift of the
South American plate. The model
reproduces features of the plates’
interaction, including the rolling
back of the subducting Nazca
plate, and the forcing down of
portions of the continental plate
under the plateau.
NEUROSCIENCE where they provide controlled environments MARCS, they find that the stars are up to
A life of regret for key biochemical reactions. But some 400 K hotter than previously calculated, with
bacteria contain protein shells that do a temperatures typically around 3,000–4,000 K.
Nature Neurosci.doi: 10.1038/nn1514 (2005) similar job. A team led by Todd Yeates at the
Regret springs from a region of the brain University of California, Los Angeles, CELL BIOLOGY
called the medial orbitofrontal cortex, determined the structure of one such Gas binding
according to a study that used functional organelle, a carboxysome, which is involved
magnetic resonance imaging to analyse in processing carbon. Its building blocks Cell122,195–207 (2005)
peoples’ response to a gamble. form hexagonal plates (pictured below)that Nuclear receptors are a family of proteins that
A team led by Raymond Dolan of are assembled into a polyhedral shell, similar can switch some genes on and off, but the
the Wellcome Department of Imaging to the protein coats of some viruses. The shell ligands they normally bind are known in only
Neuroscience in London and Angela Sirigu also has an electrically charged hole that may a few cases.
of the Institute for Cognitive Science in Lyon control what enters and leaves the structure. Henry Krause from the Charles H. Best
offered 15 subjects the choice of two gambles, Institute in Toronto and his colleagues have
one riskier — but for higher stakes — than ASTRONOMY now identified the simple gases nitric oxide
the other. When those who took the safe Not so cool and carbon monoxide — short-lived
option were told they would have won the signalling molecules important in many
riskier bet, their medial orbitofrontal cortex Astrophys. J.628,973–985 (2005) physiological functions — as natural ligands
became active. This area then fired before the Red supergiants begin life as stars at least 15 of the Drosophilanuclear receptor E75.
regretful gambler’s later choices, suggesting it times more massive than our Sun, and then They show that the receptor includes an
is also involved in anticipating regret. swell to hundreds of times the Sun’s radius. iron-containing haem molecule within its
But observations have suggested that ligand-binding pocket. The state of oxidation
CELL BIOLOGY these stars are cooler than theories of of the haem affects the ability of the E75 ATES
Tiny organs stellar evolution can receptor to bind the gases. YE
E.
explain. A team of
Science309,936–938 (2005) astronomers has now BIOGEOGRAPHY
Scientists in California gone some way to Gluttony and sloths
have revealed the raising these stars’
molecular shape of a temperatures and Proc Natl Acad. Sci. USAdoi:
bacterial organelle. Its reconciling the two 10.1073/pnas.0502777102 (2005)
structure is uncannily lines of evidence. By The Americas were once home to at least
similar to that of certain fitting new spectral 19 genera of sloth species, some weighing
viruses. measurements of as much as an Asian elephant. It has been
Organelles are usually the light from 74 unclear whether climate change or human
found in more complex supergiant stars to hunters caused their demise, as the two hit
eukaryotic cells — the plant improved versions of much of the Western Hemisphere at roughly
chloroplast is one example — stellar-atmosphere models called the same time. To resolve the issue, David
756
© 2005 Nature PublishingGroup
11.8 Research Highlights NEW am 8/8/05 12:08 PM Page 757
NATURE|Vol 436|11 August 2005 RESEARCH HIGHLIGHTS
Steadman at the Florida Museum of Natural CE
N
History in Gainsville and his colleagues CIE JOURNAL CLUB
focused on the Caribbean, where the climate S
changed 7,000 years before humans arrived.
Peter Seeberger
Carbon dating of bones showed that the
Swiss Federal Institute
sloths disappeared only after humans
of Technology Zurich,
reached the islands. The finding adds weight
Switzerland
to the idea that hungry humans wiped out
the New World’s large mammals. A new twist to an old reaction
should break down barriers
MATERIALS between chemists, argues one
who has worked in two fields.
Natural spirals
Science 309,909–911 (2005) Every day, people in my laboratory
Spiral patterns similar to those seen in flower are performing glycosylation
heads decorate the nanoparticles made by reactions. This is the basic reaction
Zexian Cao’s team at the Chinese Academy of that connects two sugars, and it is
Sciences in Beijing (pictured top right). Like key to the study and exploitation of
the floral spirals, the microscopic swirls are carbohydrate molecules. We need
described by Fibonacci number patterns. carefully synthesized structures
The particles, measuring about 10 to probe the biological role of
micrometres across, have a silver core with a carbohydrates and explore their
silica coating. They are formed at 1270 K, therapeutic potential.
slightly above the melting point of silver but The problem is that the
well below that of silica. As the particles cool glycosylation reaction, despite
and shrink, stresses in the outer layer raise being described in 1901, is one
dimples on the shell. The patterns depend on of the least predictable
the size of the particle, the thickness of its transformations in organic
shell and the rate of cooling. synthesis. The sugars link through a
carbon and an oxygen atom. These
BIOTECHNOLOGY can bond in two mirror-image
A clean break configurations, producing two
when they were engineered to be close stereoisomers with different
Nature Methodsdoi:10.1038/nmeth787 (2005) together on the chromosome. This positional biological activity. Controlling the
Separating a genetically engineered protein effect suggests that extrinsic factors, such as stereochemistry of some linkages is
from the bacterial cell that made it has got spatial variation within the cell’s nucleus in easy, but for some it is very hard.
easier, thanks to a trick developed by David the concentration of molecules that control This was a problem when my group
Wood and his colleagues at Princeton gene activity, may cause the noise. synthesized a carbohydrate vaccine
University. for malaria, for example.
They fuse the gene encoding the target CLIMATE CHANGE Recent work by Geert-Jan Boons
protein with genes encoding a sticky tail. The Greenland gets warmer and his colleagues at the University
tail consists of a molecule called intein, which of Georgia (Angew. Chem.44,947-
connects to the target protein, and a stretchy Geophys. Res. Lett.32,L14705 (2005) 949; 2005) describes a nice trick
polypeptide similar to elastin. When the cell Researchers have teased apart two factors that will offer control over some
extract is heated, the tails get entangled, and affecting Greenland’s climate, collecting data reactions. A group needed to shield
the protein precipitates out of the mix. The in agreement with climate-model predictions a reactive site in the first sugar is
intein links disintegrate in 4–10 hours, that global warming is having a chosen so that it is also a chiral
severing the protein’s unwanted tail. disproportionately large effect on the island. auxiliary — a chemical add-on that
Temperature trends in Greenland are allows only one stereoisomer to
GENETICS dominated by local climate patterns such as form. The auxiliary forces the
Noisy expression the North Atlantic Oscillation (NAO), which molecule into a ring-shaped
is thought to have cooled Greenland since the intermediate that the incoming
Nature Genet.doi:10.1038/ng1616 (2005) 1930s. To detect the change underlying the sugar can attack from only one side.
Fluctuating protein levels inside cells can oscillation’s effect, Petr Chylek of Los Alamos This shows that even in a
arise from seemingly random variation in the National Laboratory in New Mexico and seemingly mature field there is
rate that genes are expressed. To study the Ulrike Lohmann of the Swiss Federal room for innovation. Organic
source of such noise, Alexander van Institute of Technology in Zurich found a chemistry routinely uses chiral
Oudenaarden of the Massachusetts Institute weather station on Greenland’s northeast auxiliaries, but carbohydrate
of Technology and his colleagues looked coast where temperatures for the past 30 chemistry has been seen as a
at weakly active genes in the yeast years seem unaffected by the NAO. separate discipline. Having worked
Saccharomyces cerevisiae. Fluctuations in the Temperatures at this station are rising 2.2 in both fields, I am trying to break
activity of these genes became synchronized times faster than the global average. down the boundaries.
757
© 2005 Nature PublishingGroup
11.8 News 758 McP 9/8/05 2:33 PM Page 758
Vol 436|11 August 2005
NEWS
Medics braced for fresh superbug
GES If you haven’t heard of Acinetobacter, chances
MA are you soon will. Reports that the bacterium is
TY I infecting US army personnel, mostly soldiers
T
GE wounded in Iraq, are drawing attention to the
AFP/ little-known organism. Medical experts are
UEZ/ concerned that if antibiotic overuse in
J. G hospitals is not curbed, drug-resistant strains of
Acinetobacter baumanniicould become a seri-
ous killer in intensive-care wards worldwide.
The latest data come from two US army
medical centres, the Landstuhl Regional Med-
ical Center in Germany and the Walter Reed
Army Medical Center in Washington DC.
Drug-resistant A. baumanniihas infected at
least 240 US soldiers since 2003, and five seri-
ously ill patients who shared wards with them
became infected and died.
“It’s a big problem,” says Colonel Bruno
Petrucelli, the army’s director of epidemiology
and disease surveillance, pointing out that
both civilian and military hospitals are being
hit. “Hospitals are dangerous places to be.”
Resistance fighting
Detailed epidemiological data are sparse
because surveillance of Acinetobacteris vol- Hard case: Acinetobacter(below) rapidly evolves drug resistance, and survives hygiene measures.
untary, but the number of outbreaks seems to
be rising alarmingly. The UK Health Protec- But it can kill people who to develop resistance. Acine- C
D
tion Agency (HPA) says that, in the past four are already sick or whose tobacteracquires resistance R/C
R
years, outbreaks have been reported in 24 immune systems are com- to even more drugs than A
C
London hospitals alone. And Arjun Srini- promised. And it has several MRSA; doctors have been J.
vasan, an epidemiologist from the Centers for characteristics that could forced to turn to colimycin,
Disease Control and Prevention in Atlanta, make it a serious threat in an antibiotic abandoned in
Georgia, who coordinates a programme on intensive-care wards. “The the 1960s because of its rela-
hospital-acquired infections in 300 US med- situation needs to be moni- tive toxicity. On occasion,
ical centres, says that the number of cases is tored,” says Pitt. even this remedy has failed.
rising there too, although they are still rela- Most worrying is the bac- Petrucelli says that mili-
tively uncommon. terium’s ability to evolve tary field hospitals are par-
“Twenty years ago, only around 1.5% of resistance to a broad range of ticularly guilty of overusing
all cases of pneumonia acquired in the US hos- antibiotics unusually quickly, antibiotics. Sterility is diffi-
pitals we survey were caused by leaving few treatments for cult to maintain, so doctors tend to
“40% of our patients
Acinetobacter infection,” he those who succumb. Scientists throw broad-spectrum antibiotics at the
who become infected
says. “Now that number is 7% do not understand how this wounded. “But this removes options later
and most are drug-resistant.” with Acinetobacterdie happens, but they know that on,” he warns.
Similar increases have been the microbe has many ways to Yehuda Carmeli, an infectious-disease
because of it.”
seen for other types of infec- acquire resistance genes. And physician at the Tel Aviv Sourasky Medical
tion, such as in blood or at surgical sites. some strains naturally contain enzymes that Center in Israel, describes the situation as “a
Unlike methicillin-resistant Staphylococcus break down some antibiotics. real danger”. The bacterium is endemic in
aureus (MRSA), another serious hospital- Researchers are also studying how the bac- many wards in his hospital, surviving hygiene
acquired, drug-resistant infection, A. bau- terium can survive on dry surfaces, particu- measures that have seen off MRSA.
mannii is unlikely to infect many outside larly plastics, for many weeks. This enables Carmeli also speculates that the bacterium
hospitals. “This bug is not the same as MRSA,” bacteria to hang around on wards even when has become more virulent as it has acquired
says Tyrone Pitt, a bacteriologist at the HPA. strict hygiene is maintained. antibiotic resistance. “We have calculated that
“It is not a normal human pathogen.” The Those handling the outbreaks stress the 40% of our patients who become infected with
bacterium normally lives in soil or water and importance of using antibiotics sparingly, to A. baumanniidie because of it,” he says. ■
is not very pathogenic in healthy people. reduce the selective pressure on the bacterium Alison Abbott
758
© 2005 Nature PublishingGroup
©2005 Nature Publishing Group
11.8 News 759 McP 9/8/05 2:58 PM Page 759
NATURE|Vol 436|11 August 2005 NEWS
PESTICIDE-PROOF FLIES
HAVE UNEXPECTED EDGE
Gene for DDT tolerance
offers extra survival
advantages.
www.nature.com/news
Preparations get under way for tsunami warning system
Tsunami experts from around the world met where to place another 17 by the end of the AP
last week to hammer out a framework that will year. A network of such gauges would allow NG/
O
bring countries at risk of another Indian Ocean information from one area to reach at-risk W
A
tsunami up to minimum safety standards. The countries on the other side of the ocean. WEER
meeting set the stage for upgrading tidal gauges The meeting also created a consortium to A.
throughout the region and for establishing an deploy deep-sea pressure sensors, which have
early-warning network by June 2006. been developed in the United States and Ger-
When a powerful tsunami devastated coast- many. There has previously been rivalry
lines around the Indian Ocean on 26 Decem- between the two countries over the technol-
ber 2004, killing almost 300,000 people, there ogy. But when Germany presented plans to
was no effective warning, even though the put two of its as yet untested buoys in Indone-
waves took several hours to reach some An official checks for hints of a tsunami at the sian waters in October, the United States asked
affected countries. Calls for a dedicated warn- National Disaster Warning Centre in Thailand. to place one of its buoys nearby, so that the sys-
ing system in the region began almost as soon tems can be calibrated. Member countries
as the extent of the disaster became apparent. also set up to address the creation of networks such as Australia and India will also now be
As a result, the Intergovernmental Coordina- for seismic and ocean monitoring, and to assess able to use and refine the technology.
tion Group of the Tsunami Warning and Miti- the respective needs of the countries involved. The possibility of setting up a regional
gation System was set up by the United Nations Since the disaster, 25 of the group’s members tsunami-warning centre was not discussed.
in June. Its first meeting was held in Perth, Aus- have set up communication centres linked up And international agencies have still to decide
tralia, last week. Representatives from the to seismic-monitoring stations in Tokyo and how to divide up resources to help countries,
group’s 27 member nations, and observer coun- Hawaii.Tidal gauges are also being deployed especially the smaller ones, prepare for future
tries including Germany, Japan and the United to provide further data on any developing tsunamis. Such issues should be ironed out at
States, selected a chair, P. S. Goel, who is secre- tsunami. Six gauges sending real-time data the group’s next meeting in Hyderabad, India,
tary of the Indian government’s Department of have been established since December 2004, in December. ■
Ocean Development. Working groups were and the working group will decide when and David Cyranoski
Scans provide picture of brain activity
Neuroscientists who use a popular scanning In 2001, researchers in Germany showed minutes of the Clint Eastwood film The
technique to look at brain activity can that fMRI scans could be correlated with Good, the Bad and the Ugly.
breathe a sigh of relief, researchers say. brain-cell activity in anaesthetized monkeys The researchers built a computer model to
A paper in last week’s Sciencesuggests (N. K. Logothetis et al. Nature412,150–157; convert the measured activity into fMRI
that, as well as identifying which parts of the 2001). But until now, no one had done the images. They then compared these predicted
brain are activated during certain tasks, the same thing for conscious human brains. images with actual fMRI scans taken of 11
scans also provide a measure of actual brain- Malach joined forces with a group at the healthy volunteers who watched the same
cell activity (R. Mukamel et al. Science309, University of California, Los Angeles, led by movie clip. In general, the model was accurate
951–954; 2005). Although researchers have neurosurgeon Itzhak Fried, that works with half to three-quarters of the time, but for
been working on this assumption, it is the patients suffering from severe epilepsy. certain points in the movie, agreement
first study to show this in humans. Before they can have surgery, the patients reached 90%. The correlation is encouraging,
Functional magnetic resonance imaging, spend several days with electrodes wired the team says, given the dramatic differences
or fMRI, has been widely used to investigate into their brains so that the doctors can in the patients and their settings.
which parts of the brain are active during pinpoint the source of their seizures. Fried’s The results apply to only one area of the
anything from being in love to telling lies. But team took advantage of this situation by brain, and describe the reaction to just one
some researchers have questioned whether recording the activity of the brain cells in kind of stimulus. But some neuroscientists
the technique reveals anything significant two epilepsy patients who were shown nine are pleased that the study is looking at real
about the brain’s workings. This is because human behaviour.
fMRI does not measure brain-cell activity “They’re actually getting AAS
A
directly, but changes in blood flow within the a little bit closer to what the
brain in response to various stimuli. brain is doing, and I think
The latest results could put those doubts that’s great,” says
to rest says the study’s lead author, Rafael neurophysiologist David
Malach of the Weizmann Institute of Science Leopold of the US National
in Rehovot, Israel. “It’s a great relief to know Institute of Mental Health
that these studies in which dozens of labs are in Bethesda, Maryland. ■
now involved are not a waste of time,” he says. Models using brain-cell data show good agreement with real scans. Erika Check
759
© 2005 Nature PublishingGroup
©2005 Nature Publishing Group
