Nature (Vol. 435, No. 7044, 16 June 2005)

143 Pages·2005·11.333 MB·English

Volume 435 Number 7044 pp855-1002
In this issue (16 June 2005) • Books and Arts
• News and Views
• Editorials • Brief Communications
• Research Highlights • Brief Communications Arising(this
• News content only available online)
• News Features • Articles
• Business • Letters
• Correspondence • Technology Features
• Commentary • Naturejobs
• Futures
Editorials
Risks and benefits of dual-use research p855
Negotiations over a sensitive scientific publication that could be misused by bioterrorists highlight
trouble ahead unless appropriate guidelines are developed.

Save the people, too p855
Conservationists must pay attention to the needs of local human, as well as animal, populations.

Much whaling and gnashing of teeth p856
The International Whaling Commission may be messy, but it's the only game in town.

Research Highlights
Research highlights p858

News
Biologists asked to breed a culture of responsibility in face of terrorism p860
International conference says scientists must face up to the risks of their own research.
Erika Check

US teams join hands to build dexterous robots p861
Competition with Asia prompts united effort in robotics.
Gregory Huang

Whaling divisions deepen as Japan pushes for credibility p861
Pro-whaling allies likely to edge their first majority at international whaling conference.
David Cyranoski

Gloomy outlook for Blair p862
British prime minister Tony Blair hopes to make significant progress on climate change at the upcoming
G8 summit. The United States is standing in his way, but his efforts may at least benefit climate research.

Geologists call time on dating dispute p865
Relations thaw as opposing sides vote on what to call latest geological period.
Jim Giles

Sidelines p866

German tobacco papers reveal lump sums for health experts p866
Critics say payments responsible for country's lax smoking laws.
Quirin Schiermeier

Look out for rough drafts of mammal genomes p867
Biologists disappointed that many new genome project species will get only low-density coverage.
Erika Check

News in brief p868

News Features
Conservation in Myanmar: Under the gun p870
Western conservation biologists working in Myanmar have been accused of colluding with a brutal military
regime — charges they deny. Duncan Graham-Rowe reports from this pariah state.

Science education: Hothouse High p874
Do US high schools dedicated to science generate future academics or burnt-out whiz kids? Kendall Powell
catches up with some of the first pupils to graduate from 'nerd school'.

I
Stem-cell therapies: The first wave p877
Treatments that use stem cells to replace damaged or diseased tissues are thought to lie many years away.
But the cells might find other clinical applications in the near future, says Catherine Zandonella.

Business
No longer the upstart p879
The US biotechnology industry's lobby shop is at last making its mark. Its incoming president may have
taken some flak for quitting Congress but, as Meredith Wadman discovers, he's relishing the change.

Correspondence
Coordinating vaccine use is best way to combat polio p881
Irving S. Johnson

Don't drop current vaccine until we have new ones p881
Vadim I. Agol, Konstantin Chumakov, Ellie Ehrenfeld and Eckard Wimmer

Images: keep a distinction between beauty and truth p881
Daniel A. Peterson

Commentary
Japan's whaling plan under scrutiny p883
Useful science or unregulated commercial whaling? Nicholas J. Gales, Toshio Kasuya, Phillip J. Clapham
and Robert L. Brownell Jr consider the scientific merits of Japan's whaling activities.

Books and Arts
Crash and burn p885
Even 'artificial organisms' such as commercial companies find immortality out of reach.
Adrian Woolfson reviews Why Most Things Fail: Evolution, Extinction and Economics by Paul Ormerod

Politics and disease p886
Adrian Sleigh reviews Twenty-First Century Plague: The Story of SARS by Thomas Abraham

The power of collecting p887
Brendan Tobin reviews Trading the Genome by Bronwyn Parry

Science in culture: Trees of knowledge p888
Georg Lichtenberg visualized a new branch of science.
Martin Kemp

News and Views
Low-temperature physics: Tunnelling into the chill p889
The trend towards ever smaller electronic instruments had left refrigerators out in the cold. Now a
practical, compact device uses quantum mechanical tunnelling to cool close to absolute zero.
Jukka Pekola

Genetics: LINEs in mind p890
At least half the human genome consists of mobile elements, such as LINEs, some of which can jump around
the genome. These elements have been crucial in genome evolution, but they may also contribute to human
diversity.
Eric M. Ostertag and Haig H. Kazazian, Jr

Malaria: Fungal allies enlisted p891
The mosquito-killing capabilities of fungi can in principle be deployed in the fight against malaria.
But long experience of unfulfilled hopes in this complex arena shows the need to proceed cautiously.
Yannis Michalakis and François Renaud

Engineering: Skimming the surface p893
Models of the microscopic contact area between two surfaces work surprisingly well, or fail completely,
depending on the aspects of adhesion or friction being investigated. A simulation now shows how the details
matter.
Jacob N. Israelachvili

50 and 100 years ago p894

Cell biology: Powerful curves p895
A cell's contents are organized by a scaffolding of microtubules. These long, thin polymers continuously
grow and shrink, and the structures of two forms of the constituent protein provide clues to how this
occurs.
L. Mahadevan and T. J. Mitchison

Nuclear physics: Elusive magic numbers p897
Gaps in nuclear levels, which cause nuclei with 'magic' numbers of protons or neutrons to be especially
stable, seem to be different for nuclei with an excess of neutrons. But are all magic numbers aberrant
in exotic species?
Robert V. F. Janssens

II
Developmental biology: One source for muscle p898
Producing muscle as an embryo, and making or repairing it as an adult, could be considered to be quite
different processes. But it seems that cells that share a common origin carry out both of these tasks.
Iain W. McKinnell and Michael A. Rudnicki

Cell biology: New cog for a familiar machine p899
During cell division, intricate cellular machinery separates duplicated DNA into daughter cells.
Unexpectedly, the assembly of this crucial apparatus seems to rely on components other than proteins and
DNA.
Mary Dasso

Corrections p900

Brief Communications
Genetics: Relatedness among east African coelacanths p901
Scattered groups of these ancient fish may all stem from a single remote population.
Manfred Schartl, Ute Hornung, Karen Hissmann, Jürgen Schauer and Hans Fricke

Brief Communications Arising
Food-web topology: Universal scaling in food-web structure? pE3
J. Camacho and A. Arenas

Food-web topology: Universal scaling in food-web structure? (reply) pE4
Diego Garlaschelli, Guido Caldarelli and Luciano Pietronero

Articles
Somatic mosaicism in neuronal precursor cells mediated by L1 retrotransposition p903
Alysson R. Muotri, Vi T. Chu, Maria C. N. Marchetto, Wei Deng, John V. Moran and Fred H. Gage

Nucleotide-dependent bending flexibility of tubulin regulates microtubule assembly p911
Hong-Wei Wang and Eva Nogales

Letters
Widespread magma oceans on asteroidal bodies in the early Solar System p916
Richard C. Greenwood, Ian A. Franchi, Albert Jambon and Paul C. Buchanan

High-frequency acoustic waves are not sufficient to heat the solar chromosphere p919
Astrid Fossum and Mats Carlsson

'Magic' nucleus 42Si p922
J. Fridmann, I. Wiedenhöver, A. Gade, L. T. Baby, D. Bazin, B. A. Brown, C. M. Campbell, J. M. Cook, P.
D. Cottle, E. Diffenderfer, D.-C. Dinca, T. Glasmacher, P. G. Hansen, K. W. Kemper, J. L. Lecouey, W.
F. Mueller, H. Olliver, E. Rodriguez-Vieitez, J. R. Terry, J. A. Tostevin and K. Yoneda

Triplet−singlet spin relaxation via nuclei in a double quantum dot p925
A. C. Johnson, J. R. Petta, J. M. Taylor, A. Yacoby, M. D. Lukin, C. M. Marcus, M. P. Hanson and A. C.
Gossard

The breakdown of continuum models for mechanical contacts p929
Binquan Luan and Mark O. Robbins

Extent, duration and speed of the 2004 Sumatra−Andaman earthquake imaged by the
Hi-Net array p933
Miaki Ishii, Peter M. Shearer, Heidi Houston and John E. Vidale

Tracking the rupture of the M = 9.3 Sumatra earthquake over 1,150 km at teleseismic
w
distance p937
Frank Krüger and Matthias Ohrnberger

Cortical growth marks reveal extended juvenile development in New Zealand moa p940
Samuel T. Turvey, Owen R. Green and Richard N. Holdaway

The initiation of liver development is dependent on Foxa transcription factors p944
Catherine S. Lee, Joshua R. Friedman, James T. Fulmer and Klaus H. Kaestner

A Pax3/Pax7-dependent population of skeletal muscle progenitor cells p948
Frédéric Relaix, Didier Rocancourt, Ahmed Mansouri and Margaret Buckingham

A common somitic origin for embryonic muscle progenitors and satellite cells p954
Jérôme Gros, Marie Manceau, Virginie Thomé and Christophe Marcelle

Notch/ -secretase inhibition turns proliferative cells in intestinal crypts and adenomas
into goblet cells p959
Johan H. van Es, Marielle E. van Gijn, Orbicia Riccio, Maaike van den Born, Marc Vooijs, Harry Begthel,
Miranda Cozijnsen, Sylvie Robine, Doug J. Winton, Freddy Radtke and Hans Clevers

III
Notch signals control the fate of immature progenitor cells in the intestine p964
Silvia Fre, Mathilde Huyghe, Philippos Mourikis, Sylvie Robine, Daniel Louvard and Spyros
Artavanis-Tsakonas

In vivo imaging of specialized bone marrow endothelial microdomains for tumour
engraftment p969
Dorothy A. Sipkins, Xunbin Wei, Juwell W. Wu, Judith M. Runnels, Daniel Côté, Terry K. Means, Andrew D.
Luster, David T. Scadden and Charles P. Lin

Stem cell division is regulated by the microRNA pathway p974
S. D. Hatfield, H. R. Shcherbata, K. A. Fischer, K. Nakahara, R. W. Carthew and H. Ruohola-Baker

Crystal structure of thymine DNA glycosylase conjugated to SUMO-1 p979
Daichi Baba, Nobuo Maita, Jun-Goo Jee, Yasuhiro Uchimura, Hisato Saitoh, Kaoru Sugasawa, Fumio Hanaoka,
Hidehito Tochio, Hidekazu Hiroaki and Masahiro Shirakawa

Structural basis for the promiscuous biosynthetic prenylation of aromatic natural products
p983
Tomohisa Kuzuyama, Joseph P. Noel and Stéphane B. Richard

Technology Features
Genomics: Getting down to details p991
MicroRNAs that tweak gene expression, single nucleotide polymorphisms in population genetics, and
individual genome sequencing: Caitlin Smith takes a look at three fast-moving areas in genomics.
Caitlin Smith

Genomics: Big tasks for small molecules p991

Genomics: Genotyping gets up to speed p992

Genomics: SNPs and human disease p993

Table of suppliers p995

Naturejobs
A global view p997
Paul Smaglik

An eastern promise of regeneration p998
The East Coast corridor of New Jersey, Delaware and Pennsylvania is poised for renewed growth in biomedicine.
Claudia Caruana investigates.
Claudia Caruana

Futures
Damned if you don't p1002
A casual conversation.
Lucy Bergman
IV
16.6 Editorial 855-856 NS 14/6/05 3:15 PM Page 855
www.nature.com/nature Vol 435 |Issue no. 7044|16 June 2005
Risks and benefits of dual-use research
Negotiations over a sensitive scientific publication that could be misused by bioterrorists highlight trouble
ahead unless appropriate guidelines are developed.
S
cientists, security experts and journals have done a great deal that the paper’s potential to inform biosecurity efforts outweighed
to face up to the risk of bioterrorism, but there is still consider- the risk of it giving a blueprint to terrorists. So the journal decided
able uncertainty over how to handle ‘dual use’ research with to publish.
outcomes that might be used to do harm (see page 860). This fact is Each of the parties to this dispute could have acted differently. For
underscored by confusion about a paper on such research that was instance, the apparent breakdown in initial communication between
accepted for publication last month by the Proceedings of the National Wein and the HHS implies a cursory approach to such a sensitive
Academy of Sciences (PNAS). matter on both sides and a lack of a robust system for such alerts by
The episode began on 25 May, when the journal announced that it responsible researchers.
would publish a paper by Lawrence Wein, a professor of management The HHS did not fund Wein’s work, and has never intervened in
at the Stanford University Graduate School of Business, California. a publication in this fashion before. In doing so, however, it has
Working with a graduate student, Wein had constructed a model of raised the profile of the issue. The department might have accom-
a bioterrorist attack on the US milk supply. Stewart Simonson, assis- plished more by working behind the scenes with Wein and the dairy
tant secretary for public health emergency preparedness at the US industry to increase safety, instead of taking action against a journal.
Department of Health and Human Services (HHS), was shown the Much of the information in Wein’s paper is readily available on the
paper by a reporter, who had obtained a copy under embargo. He Internet anyway.
promptly asked the National Academy of Sciences, which publishes PNASfollowed its normal procedures but was prudent to allow a
the journal, not to release it. brief delay to listen to the HHS. Having previously committed to the
Simonson’s concern, which was shared by other officials, was that paper, in the absence of any significant new security risks being
details of the paper could be helpful to terrorists. The National Acad- raised, it should now stick to its decision. But there will doubtless
emy agreed to delay publication of the paper and met with Simonson follow a broader debate on whether such papers should be submitted
and other HHS officials on 7 June. As Naturewent to press, the to, and accepted by, a high-profile scientific journal.
National Academy had not announced how it would move forward, The greatest concern is in the need for clarity. It is important to
but seemed inclined to publish the paper essentially unmodified. develop clear guidelines about what research is considered sensitive,
Both Wein and the journal were well aware of the sensitive nature what is expected of researchers whose work produces dual-use
of this paper. In fact, Wein briefed Simonson’s office on the research outcomes, and how the government should in practice respond with-
last autumn, and Simonson says that he conveyed his concerns about out losing the priceless virtues of open scientific scrutiny. Without
the work to Wein at that time. Wein contradicts that statement, such clarity, officials insensitive to those virtues may institute
maintaining that the HHS never replied to his briefing. When Wein precautionary measures that reach far beyond what is appropriate.
submitted his paper to PNAS, the journal sent it through two The US National Science Advisory Board for Biosecurity, which
layers of review, as specified by many journals, including Nature, in was set up a year ago by the US government to address such concerns,
2003 — one for scientific accuracy and one for biosecurity. None will hold its first meeting at the end of this month, and will need to
of the reviewers opposed publication, and the editors concluded act promptly. ■
Save the people, too why the motivations and actions of conservation biologists who are
working in Myanmar, with the blessing of its brutal military regime,
merit close scrutiny.
Conservationists must pay attention to the needs of In the past, such scrutiny has been uncomfortable for some of the
local human, as well as animal, populations. individuals concerned — most notably following the 1997 publica-
tion of an article in The Observer, a UK newspaper, entitled ‘Save
T
o have real passion for one’s work is a wonderful thing. And the rhino, kill the people’. This linked such venerable bodies as the
there are few people more passionate than the biologists who Smithsonian Institution in Washington DC and the Wildlife Conser-
strive to preserve biodiversity across the developing world. vation Society, based in New York, with abuses of human rights in the
Many are prepared endure physical privations, infectious diseases, southeast Asian nation formerly known as Burma.
low pay and threats of violence, all in the name of conservation. The biologists who were singled out for criticism in that article
But passion can sometimes distort judgment. Just as starry-eyed argue, with good cause, that it misrepresented their efforts. And it
lovers may be blind to one another’s faults, a true believer in any cause is apparent from a News Feature on page 870 of this issue that they
can ignore uncomfortable facts that conflict with its goals. That is are working with clear consciences, despite having to engage on
855
© 2005 Nature PublishingGroup

©2005 Nature Publishing Group
16.6 Editorial 855-856 NS 14/6/05 3:15 PM Page 856
EDITORIALS NATURE|Vol 435|16 June 2005
some level with the military regime if they are to achieve their goals. people, and should bring them tangible benefits. But the annals of
Yet it is important to ask whether the distorting lens of passion has conservation are littered with instances of people being seen as obsta-
come into play. The imminent threat to Myanmar’s biodiversity is not cles that must be removed to make way for parks and reserves. This
in doubt, nor is the desire of Burmese conservationists for foreign isn’t even limited to undemocratic countries: in the United States,
assistance. It is also good to hear that some biologists working in decades ago, conservationists pursued projects such as the Shenan-
Myanmar have sought the views of ordinary Burmese people. doah National Park in Virginia,
“Conservation biologists
But some statements do give cause for concern. Attempts to justify whose creators portrayed local
engaging with a government guilty of atrocities by arguing that other mountain farmers as backward have a responsibility to
regimes are just as bad are not compelling. The suggestion that and hounded themoff their land. ensure that their efforts
Burmese exiles have exaggerated the abuses in Myanmar is dis- Given this legacy, conservation
do not conflict with local
comforting, as is the notion that conservation biologists need to use biologists have a responsibility to
people’s rights or lend
‘charm and guile’ to convince suspicious politicians back in the ensure that their efforts do not
United States that they are not abetting the Burmese junta. conflict with local peoples’ rights, legitimacy to regimes
These may just be poorly chosen words. But it is hard not to or lend legitimacy to regimes that have dismal
wonder, on hearing the stories of those working in Myanmar, that have dismal human-rights human-rights records.”
whether some conservation biologists are prone to rush to the aid of records. This doesn’t mean that
threatened biota first, and to wrestle with the wider political and they shouldn’t work at all in countries such as Myanmar. But they
humanitarian implications only later. If that’s the case, it is a danger- should set out for their field sites with their eyes wide open, having
ous tendency. As any psychologist will tell you, the human mind is researched the humanitarian issues and engaged with parties who
adept at conjuring up post hoc justifications for a course of action that may not share their view that conserving biodiversity is the over-
has already been decided. whelming priority for the region in question. That will build more
We should also heed the lessons of history. Today it is widely confidence that saving the rhino doesn’t require unacceptable com-
accepted that effective conservation requires the involvement of local promises on human rights. ■
Much whaling and
“Resolutions adopted by the IWC against Japan’s whale research
programmes are political statements that have nothing to do with
gnashing of teeth science,” sniffed Joji Morishita, a spokesman for Japan’s fisheries
agency, in a statement issued during the meeting.
Opponents of whaling continue to regard Japan’s research pro-
The International Whaling Commission may be gramme as an affront to conservation efforts, and Japan has been
messy, but it’s the only game in town. hard-pressed to come up with convincing, peer-reviewed articles
supporting it. Now it says it needs an even larger programme to
M
arine biologists at this month’s annual meeting of the address the demands of the IWC’s scientific committee. More
International Whaling Commission (IWC) at Ulsan in sophisticated analysis requires a greater sample size — who can
South Korea will require considerable patience and forti- argue with that?
tude. “It’s like banging your head against the wall,” complained one Given all this chicanery, one might be tempted to ask why
scientist there for the preliminary scientific-committee meeting. researchers should bother to spend so many long days and nights in
The main bone of contention at this year’s meeting is a proposal by South Korea engaging in the IWC process.
Japan to double the scope of its ‘research whaling’ programme — its But buffeted by criticism as it may be, the IWC continues to
thinly disguised arrangement to continue some whaling despite a implement the international regime that stands in the way of
moratorium on commercial whaling that the IWC implemented in unregulated whaling — and of
1986 (see Nature435,550; 2005). The plan may get a sympathetic the probable extinction of several “The IWC continues
hearing at Ulsan because pro-whaling nations now seem to have a whale species. Before the mora- to implement the
majority on the IWC for the first time (see page 861). This has come torium, Japan’s yearly quota of
international regime that
about because 23 new members — some with a dubious interest in minke whale in the Southern
stands in the way of
whales, dead or alive — have joined the IWC in the past five years, Hemisphere was 1,941; under its
taking its total membership to 62. Whaling opponents whisper that proposed research programme, it unregulated whaling.”
Japan “goes shopping”, as one of them puts it, for small, poor coun- would catch 935.
tries such as Kiribati and Tuvalu in the south Pacific to join the body And despite its grouching, Japan wants to be seen as a good
in exchange for aid. international citizen; it is unlikely to pack up its marbles and go
It is unlikely, however, that the new composition of the IWC will home. It will remain at the table, infuriating its opponents at times
lead to radical changes in whaling rules, which would require a but basically conforming with an imperfect international process.
three-quarters majority. Japan’s research programme was never actu- Conservation biologists should do likewise, cajoling more friendly
ally approved by the body in the first place; Japan has sometimes nations to sign on and grimly adhering to the only path that can, in
chosen to brush the IWC’s non-binding views on the matter aside. its convoluted way, save the whales. ■
856
© 2005 Nature PublishingGroup

©©22000055 NNaattuurree PPuubblliisshhiinngg GGrroouupp
16.6 Research Highlights MH 13/6/05 10:31 AM Page 858
Vol 435|16 June 2005
RESEARCH HIGHLIGHTS
Culture shock Y/SPL
TLE
H
G
Nature Med.doi:10.1038/nm1268 (2005);Proc. Natl KI
Acad. Sci. USAdoi:10.1073/pnas.0503596102 (2005); N: R.
O
SMcioernec ethdaoni 1 107.1012 m6/ilslcioienn pcee.o11p14le0 w16o (r2ld0w05id)e are MPRESSI
imnfaejoctre lidv ewri tdhis tehaes vei.r Uusn tdhearts tcaanudsiensg h tehpea litfieti sc yCc,l ae TIST’S I
of the virus (pictured) is essential for developing AR
effective treatments, but progress has been
limited because the virus is difficult to grow
in culture and therefore hard to study.
In independent papers, three teams now report
successful in vitrosystems for propagation, using
a unique hepatitis C virus clone derived from a
Japanese patient by Takaji Wakita at the Tokyo
Metropolitan Institute for Neuroscience. His
group, and teams headed by Francis Chisari at
the Scripps Research Institute, California, and
Charles Rice at Rockefeller University, New York,
propagated this clone in a human liver-cancer cell
line. Their systems produce high yields of virus
that can be used to infect further cells.
MATERIALS devices clean. Titanium coated with the according to Paul Weiss’sgroup at the
Foul play antifouling polymer remains relatively Pennsylvania State University, University Park.
cell-free in a culture of tissue-forming His team persuaded 1-adamantanethiol
J. Am. Chem. Soc.127,7972–7973 (2005) fibroblasts for months. molecules to self-assemble into a
Mussels stick tenaciously to the hulls of boats, monolayer on gold. Because these
and this increases the boats’ drag. But Phillip IMMUNOLOGY molecules’ interactions are weak, they can
Messersmith and colleagues at Northwestern Poxy antibodies be displaced by other molecules that bind to
University in Illinois, Evanston, plan to turn gold, such as alkanethiols. This should make
one of their own proteins against them. Nature Med. doi:10.1038/nm1261 (2005) it possible to print patterns of molecules,
They have developed an antifouling More than 200 years after Edward Jenner perhaps with conducting or sensing
polymer that prevents biological adhesion realized that infection with cowpox made properties, into the 1-adamantanethiolate
— a non-stick compound is anchored to a milkmaids resistant to the smallpox virus, a layer. The surrounding layer would
surface by a peptide that mimics the adhesive group led by Genoveffa Franchini from the prevent the pattern spreading by diffusion,
protein of blue mussels (Mytilus edulis, National Cancer Institute in Bethesda, overcoming a problem encountered
pictured). The non-stick element is a polymer Maryland, has discovered how a smallpox when some molecules are printed on
made from an artificial analogue of glycine. vaccine based on the vacciniavirus bare gold surfaces.
The material could have applications not confers immunity.
only in marine engineering but also in Using macaques infected with monkeypox MEDICINE
medicine, for example, to keep implanted virus, which is a good model for smallpox Barrier grief
infection in humans, the researchers showed
M
that the protective power of the vaccine is J. Clin. Invest. 115,1607–1615 (2005) O
C
mratehdeiar ttehda nby i ttsh Te icmelmls.u Tnhee s Bys cteemlls’s p Bro cdeullcs,e Tpnoe cuamusoen miaeenminugsitt fisin, Sdt ritesp wtoacyo caccurosss the UREPL.
AT
antibodies that bind specific poxvirus blood–brain barrier. A group led by Jörg N
T/
proteins — and the researchers found that Weber of the Charité Medical School in Berlin, OT
N
antibodies from vaccinated humans Germany, has now worked out how the DI
D
protected macaques from severe disease. bacterium damages the endothelial cells that HO
The finding may assist the search for a safer make up the barrier. They find that the R.
alternative to the current live-virus vaccine. pathogen induces programmed cell death
through two different mechanisms. One
NANOTECHNOLOGY pathway is triggered by toxins produced by
Going for gold living S. pneumoniae, the other by components
of its cell wall. The latter mechanism has
J. Am. Chem. Soc. doi:10.1021/ja042621o (2005) implications for therapeutic treatment
Spherical cages of carbon atoms that attach — antibiotics that target the S. pneumoniae
gently to gold should allow more complex cell wall might cause further tissue damage
molecular patterning of gold surfaces, through the release of cell-wall debris.
© 2005 Nature PublishingGroup

©2005 Nature Publishing Group
16.6 Research Highlights MH 13/6/05 10:31 AM Page 859
NATURE|Vol 435|16 June 2005 RESEARCH HIGHLIGHTS
A/SPL CCEaLLl lBiInOLgO GtYails WBEloSTo NdIL Ew DeISdEAdSiEng
K
ASIE
A. P J. Cell Biol. doi:10.1083/jcb.200411001 (2005) Proc. Natl Acad. Sci.USA
ON: Eggs attract sperm by releasing chemicals that doi:10.1073/pnas.0503835102 (2005)
RESSI boost calcium ion (Ca2(cid:1)) levels inside a sperm, The discovery that one mosquito can
MP so altering the direction in which it swims. transmit the West Nile virus directly to
T’S I But rather than responding to overall levels of another may help explain the surprisingly
TIS Ca2(cid:1), as previously thought, the sperm react rapid spread of the disease through
R
A
to the rate at which its concentration changes, North America.
reports a team led by Christopher Wood at Usually mosquitoes (Culex pipiens
the National Autonomous University of quinquefasciatus) pick up the West Nile
Mexico, Cuernavaca. virus by feeding on birds infected with it.
Experiments in sperm from the sea urchin But researchers led by Stephen Higgs of
Arbacia punctulatasuggest that attractant the University of Texas Medical Branch in
chemicals trigger two waves of Ca2(cid:1)that pass Galveston have shown that the virus can pass
through the sperm’s tail. The first is short and between two mosquitoes if they sip blood
rapid, the second long and slow. Blocking the simultaneously from an uninfected host. This
first rapid flux stops the sperm changing type of transmission has previously been
direction even though the second wave demonstrated in ticks and blackflies. In this
elevates Ca2(cid:1)levels, revealing a surprising VIRAL TRANSPORT case, the recipient mosquito may acquire the
complexity in calcium-ion signalling. Stowaways virus by directly ingesting infected saliva
from a feeding neighbour, but this remains
QUANTUM PHYSICS Nature Cell Biol. doi:10.1038/ncb1269 (2005) to be proven.
Lamb chops Certain viruses improve their ability to
infect cells by stowing away in structures DATA STORAGE
Phys. Rev Lett.94,223001 (2005) called internal vesicles, according to a team Pillar talk
The field theory of electromagnetism — led by Jean Gruenberg at the University of
known as quantum electrodynamics — is the Geneva, Switzerland. This means that J. Appl. Phys.97,103910 (2005)
best-tested theory in physics. But researchers infection takes place in two steps — not One way to pack more data on to magnetic
will not rest until they have tested its validity one, as previously thought. disks is to pattern the surface, defining small
in extremely strong electric fields, such as The team tracked the vesicular stomatitis dots that store single bits. Another approach
those generated by heavy nuclei. virus as it infected cultured cells. The cell is to use multiple magnetic layers, so more
To do this, Alexandre Gumberidze of the swallowed the virus into a structure called than one bit can be stored per spot.
Heavy Ion Research Centre in Darmstadt, an early endosome at the cell’s edge, as Combining the two tactics, researchers
Germany, and his colleagues measured a tiny expected. But instead of escaping straight from the University of Konstanz in Germany
split in the energy levels of a uranium ion from the endosome into the outer regions and the Hitachi San Jose Research Center in
from which all but one electron had been of the cell, the virus within its endosome California deposited multiple layers of cobalt
stripped. This made it possible to see the entered a small bubble-like vesicle. These and palladium onto a field of silicon pillars,
Lamb shift, a split in energy levels usually vesicles only fuse with the outer membrane spaced 300 nanometres apart. They stored
visible only in the single-electron hydrogen of the endosome when the complex is deep two bits per pillar, giving higher data
atom. The test was three times more precise inside the cell, releasing the virus right next densities than otherwise possible with
than the previous best measurement. to the cell’s nucleus. this scale of patterning.
JOURNAL CLUB
John Brookfield identified a genewith different sequence varies. The authors of the must have been swept clean
University of Nottingham, UK variants in a population. That Sciencepaper use DNA chips to recently by a spreading variant of a
meant looking for detectable find the frequencies of more than gene. These sweeps are evidence
A population geneticist ponders
differences between individuals 1.5million single nucleotide of adaptive change.
the evolution of his field.
— for example, as in my PhD, polymorphisms in three human Counting the number of sweeps
Since I started in the business of differences in the charges of populations. But how can we use that have affected the human
population genetics, the field has enzymes. Once a variation in a such a wealth of figures to find out genome will, I suspect, tell us that
been transformed by the gene, known as a polymorphism, about natural selection? our species is changing rapidly
extraordinary increase in size of the was identified, they tried to One tantalizing idea is that we through adaptation. That could
data sets. A recent paper in Science establish whether natural selection can measure — in an objective way explain why we seem so different
(D. A. Hinds et al. 307,1072–1079; was operating on it. — how quickly species are from our ape relatives.
2005) is a prime example of such a Now that we have DNA evolving. Genetic differences in a We might also identify the genes
set, but we have yet to exploit them. sequences, we can find single population accumulate randomly in which these changes have
In the 1970s, studies followed a nucleotide polymorphisms, in over time, so regions of the genome occurred — a perennial goal of
common pattern. First they which a single letter of the where polymorphisms are rare human evolutionary genetics.
859
© 2005 Nature PublishingGroup

©2005 Nature Publishing Group
16.6 news 860 NS 14/6/05 2:58 PM Page 860
Vol 435|16 June 2005
NEWS
RES
U
T
C
X PI
D
N
A
R
B
Biologists asked to breed a culture
of responsibility in face of terrorism
D
iplomats and biosecurity experts meet- mousepox, a virus that is related to smallpox, distributed journal — a possibility raised in
ing in Geneva this week are urging life by removing a single gene (R. J. Jackson et al. ongoing controversy over a paper that models
scientists to act responsibly and pre- J.Virol.75,1205–1210; 2001). And in 2002, a bioterrorist attack on the US milk supply.
vent potential misuse of their work. the journal Sciencepublished a paper describ- Publication of this study has been delayed after
Governments can enact laws to prosecute ing how researchers had synthesized a whole protest from the US government (see page855).
people who use science to scare or hurt the polio genome from scratch (J. Cello, A. V. Paul Some life-sciences organizations, such as
public. And they can make rules to promote and E. Wimmer Science 297, 1016–1018; the Washington-based American Society for
safety in research. But laws and rules go only 2002). Scientists played down the novelty of Microbiology and the Australian Society for
so far in heading off potential abuses of the paper, but alarm among the public was so Microbiology in Melbourne, have already
science. When it comes to weighing up the great that a member of US Congress criticized adopted codes of ethics that refer to biological
potential risks and benefits of a piece of the work and asked the US executive branch to weapons. But many experts feel that more
research, or deciding whether to publish a review policies intended to stop research being researchers should adopt codes, especially
controversial result, scientists must fill the gap used by terrorists (see Nature418,265; 2002). at local levels. An influential report issued
by adopting their own principles for proper The answers to such prob- in 2003 by the US National
“Many biologists still
conduct, say those at the Geneva conference. lems, say experts at the Geneva Academy of Sciences said that
The meeting, which runs from 13 to meeting, are codes of conduct. do not believe that awareness of potential misuse
24June, focuses on codes of conduct in life- These are statements by scien- their work could of life sciences “varies widely”
sciences research. It is the third ‘Meeting of tific societies, trade organiza- among researchers. It advised
possibly be misused.”
Experts’ — a series of conferences intended to tions or other bodies that lay out more education.
promote the international treaty that bans principles to govern their mem- Just last week, a report was
biological weapons. Formal negotiations on bers’ activities. Advocates say they would force issued by an expert US commission, chaired by
how to enforce the treaty collapsed in 2001, each researcher to think about the proper con- Harold Brown, former US secretary of defence,
but are scheduled to resume next year. duct, dissemination and use of his or her work. and Nobel laureate David Baltimore, president
Unlike physicists, who were forced to face “Developing a code of conduct really would of the California Institute of Technology in
up to the potential consequences of their work give structure to the awareness that we need to Pasadena. It recommended that individual
when nuclear weapons were developed in the create, especially among young professionals,” universities and research institutions set up
1940s, many biologists still do not believe that says Mark Smolinski of the Nuclear Threat Ini- committees to comply with biosecurity regula-
their work could possibly be misused, say tiative, an arms control think-tank based in tions and promote self-governance.
biosecurity experts. But several recent papers Washington DC. He and others want to see Experts at the Geneva meeting say that the
have highlighted how bona fide research could scientists take an active role in preventing conference is unlikely to lead to a binding
be abused by terrorists or governments devel- potential abuses of their work. international agreement on codes of conduct.
oping biological weapons. For instance, a researcher might choose to But they hope it will encourage individuals
For example, in 2001 an Australian team brief key government officials about a sensitive and institutions to take action. ■
accidentally created a deadly version of finding instead of publishing it in a widely Erika Check
860
© 2005 Nature PublishingGroup

©2005 Nature Publishing Group