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A dangerous precedent p159

A legal challenge to US stem-cell policy poses a serious threat to the federal funding system.


Plagiarism pinioned p159

There are tools to detect non-originality in articles, but instilling ethical norms remains essential.


The needs of the few p160

Developing drugs for rare diseases is a challenge that requires new regulatory flexibility.



Research Highlights

Animal biology: Savvy spiders p162


Nanotechnology: Photons make light work p162


Atmospheric chemistry: Airborne alcohol p162


Cell biology: Protein clean-up crew p162


Neuroscience: Smells affect sight p162


Chemistry: Metal–organic catalyst p162


Zoology: Follow the leader p163


Genetics: Breaking the silence p163


Cardiovascular biology: Low B cells, low plaques p163


Biotechnology: Swirling cells p163



Journal Club

Journal club p163

Tecumseh Fitch




News briefing: 2–8 July 2010 p164

The week in science.


China outlines deep-sea ambitions p166

Extra funding promised to help search for natural resources and advance ocean research.

Jane Qiu


Journals step up plagiarism policing p167

Cut-and-paste culture tackled by CrossCheck software.

Declan Butler


Solar System showdown p168

Competition is fierce as committee weighs NASA's planetary priorities.

Eric Hand


Few fishy facts found in climate report p170

Dutch investigation supports key warnings from the IPCC's most recent assessment.

Quirin Schiermeier


EU research funds to be diverted to fusion reactor p171

Ailing ITER may get bailout from framework programme.

Geoff Brumfiel


NIH may open access to clinical facility p172

Outside investigators could pay to use the Clinical Center's state-of-the-art resources.

Meredith Wadman



News Features

Evolution: Dreampond revisited p174

A once-threatened population of African fish is now providing a view of evolution in action. Laura Spinney asks what Lake Victoria cichlids have revealed about speciation.


Disputed ground p176

Finds in Turkey could answer key questions about ancient human origins, but palaeoanthropologists there must first bury their disputes. Rex Dalton reports from the field.




Unify guidelines for reviewing embryonic stem-cell research p179

Josephine Johnston


Metrics: journal's impact factor skewed by a single paper p179

Jordan D. Dimitrov, Srini V. Kaveri & Jagadeesh Bayry


Metrics: don't dismiss journals with a low impact factor p179

Jay M. Fitzsimmons & Jeffrey H. Skevington


Metrics: include refereeing as part of performance rating p179

Pedro Cintas & Elena Paoletti




Securing a future for chimpanzees p180

Fifty years after setting foot in Gombe, Jane Goodall calls for urgent action to save our closest living relatives from extinction in the wild. Conservationists and local people must collaborate, she and Lilian Pintea conclude.

Jane Goodall & Lilian Pintea


How to defend against future oil spills p182

Researchers and regulators need to keep up with the changing risks, and share information, says Arne Jernelöv, as tanker spills decline and pipeline leaks and blowouts become more of a concern.

Arne Jernelöv


The business of biodiversity p184

The value of ecosystems is largely invisible to markets. Ricardo Bayon and Michael Jenkins call on governments to drive regulatory and voluntary economic instruments that put a price on the services that nature provides.

Ricardo Bayon & Michael Jenkins



Books and Arts

Who controls malaria control? p186

Awa-Marie Coll-Seck enjoys a hard-hitting history of malaria, but takes issue with its contention that current eradication strategies are repeating the errors of the past.

Awa-Marie Coll-Seck reviews The Fever: How Malaria Has Ruled Humankind for 500,000 Years by Sonia Shah


Making the mundane urbane p187

David Bodanis reviews At Home: A Short History of Private Life by Bill Bryson


Pioneers of plant genetics to flower on stage p188

Georgina Ferry reviews Blooming Snapdragons by Liz Rothschild & Sue Mayo



News and Views

Archaeology: Early human northerners p189

A site in Norfolk, UK, provides the earliest and northernmost evidence of human expansion into Eurasia. Environmental indicators suggest that these early Britons could adapt to a range of climatic conditions.

Andrew P. Roberts & Rainer Grün


See also: Editor's summary | Letter by Parfitt et al.

50 & 100 years ago p190


Superconductivity: Revelations of the fullerenes p191

The discovery that the face-centred cubic form of the fullerene Cs3C60 is a superconductor, just as its body-centred cubic counterpart is, sheds light on the origin of superconductivity in organic materials.

Yoshihiro Iwasa


See also: Editor's summary | Letter by Ganin et al.

Cell biology: Sensing tension p192

Measuring the tension forces at specific sites in living cells is technically challenging. Now, a fluorescent biosensor protein can be used to characterize dynamic local changes in tension in migrating cells.

Andrew D. Doyle & Kenneth M. Yamada


See also: Editor's summary | Letter by Grashoff et al.

Supramolecular chemistry: More than the sum of its parts p193

Can small molecules in test tubes form assemblies containing different hydrophobic domains, like those found in cells? Yes, finds a study, suggesting new ways of isolating incompatible compounds in water.

Jan H. van Esch


Neuroscience: MicroRNA knocks down cocaine p194

Cocaine abuse results in increased craving for the drug. But in the long run, cocaine intake induces the expression of a microRNA in the brain, and this seems to limit further drug intake.

Marina R. Picciotto


See also: Editor's summary | Article by Hollander et al.

Quantum electrodynamics: A chink in the armour? p195

A measurement of the size of the proton, obtained using spectroscopy of an exotic atomic system, yields a result of unprecedented accuracy — but in disagreement with values obtained by previous methods.

Jeff Flowers


See also: Editor's summary | Letter by Pohl et al.



Striatal microRNA controls cocaine intake through CREB signalling p197

Extended cocaine taking triggers several structural and functional changes in the brain that may lead to compulsive drug seeking, but the mechanisms that regulate the process are unclear. Here, a microRNA — miR-212 — is identified that is upregulated in the striatum of rats with a history of extended access to cocaine. The authors suggest that miR-212 protects against the development of compulsive drug taking, and that it may act through the CREB protein, a known regulator of the rewarding effects of cocaine.

Jonathan A. Hollander, Heh-In Im, Antonio L. Amelio, Jannet Kocerha, Purva Bali, Qun Lu, David Willoughby, Claes Wahlestedt, Michael D. Conkright & Paul J. Kenny


See also: Editor's summary | News and Views by Picciotto

Structural mechanism of C-type inactivation in K+ channels p203

K+ channels can convert between conductive and non-conductive forms through mechanisms that range from flicker transitions (which occur in microseconds) to C-type inactivation (which occurs on millisecond to second timescales). Here, the crystal structures are presented of the potassium channel KcsA in an open-inactivated conformation and 'trapped' in several partially open conformations. The structures indicate a molecular basis for C-type inactivation in K+ channels.

Luis G. Cuello, Vishwanath Jogini, D. Marien Cortes & Eduardo Perozo


See also: Editor's summary



A 300-parsec-long jet-inflated bubble around a powerful microquasar in the galaxy NGC 7793 p209

Ultraluminous X-ray sources are the most luminous class of black hole located outside the nuclei of active galaxies. They are often associated with shock-ionized nebulae, though with no evidence of collimated jets. Now, however, it is reported that the large nebula S26 in the nearby galaxy NGC 7793 is powered by a black hole with a pair of collimated jets. The jets seem to be 104 times more energetic than the X-ray emission from the core.

Manfred W. Pakull, Roberto Soria & Christian Motch


See also: Editor's summary

The size of the proton p213

Here, a technically challenging spectroscopic experiment is described: the measurement of the muonic Lamb shift. The results lead to a new determination of the charge radius of the proton. The new value is 5.0 standard deviations smaller than the previous world average, a large discrepancy that remains unexplained. Possible implications of the new finding are that the value of the Rydberg constant will need to be revised, or that the validity of quantum electrodynamics theory is called into question.

Randolf Pohl, Aldo Antognini, François Nez, Fernando D. Amaro, François Biraben, João M. R. Cardoso, Daniel S. Covita, Andreas Dax, Satish Dhawan, Luis M. P. Fernandes, Adolf Giesen, Thomas Graf, Theodor W. Hänsch, Paul Indelicato, Lucile Julien, Cheng-Yang Kao, Paul Knowles, Eric-Olivier Le Bigot, Yi-Wei Liu, José A. M. Lopes, Livia Ludhova, Cristina M. B. Monteiro, Françoise Mulhauser, Tobias Nebel, Paul Rabinowitz, Joaquim M. F. dos Santos, Lukas A. Schaller, Karsten Schuhmann, Catherine Schwob, David Taqqu, João F. C. A. Veloso & Franz Kottmann


See also: Editor's summary | News and Views by Flowers

Ultrabright source of entangled photon pairs p217

Quantum information science requires a source of entangled photon pairs, but existing sources suffer from a low intrinsic efficiency or poor extraction efficiency. Collecting emitted photons from quantum dots can be improved by coupling the dots to an optical cavity, but this is not easy for entangled photon pairs. Now, a suitable optical cavity has been made in the form of a 'photonic' molecule — two identical, connecting microcavities that are deterministically coupled to the optically active modes of a pre-selected quantum dot.

Adrien Dousse, Jan Suffczyński, Alexios Beveratos, Olivier Krebs, Aristide Lemaître, Isabelle Sagnes, Jacqueline Bloch, Paul Voisin & Pascale Senellart


See also: Editor's summary

Polymorphism control of superconductivity and magnetism in Cs3C60 close to the Mott transition p221

Superconductivity and magnetic order are well known in C60 compounds of the form A3C60 (where A = alkali metal). The spherical C60 molecular ions in these crystals are almost always arranged in a face-centred cubic (f.c.c.) packing, except in Cs3C60, where the known superconducting phase has a body-centred cubic (b.c.c) packing. Now the f.c.c. polymorph for Cs3C60 has been isolated; it too is superconducting, although its magnetic properties are very different to those of its b.c.c counterpart.

Alexey Y. Ganin, Yasuhiro Takabayashi, Peter Jeglič, Denis Arčon, Anton Potočnik, Peter J. Baker, Yasuo Ohishi, Martin T. McDonald, Manolis D. Tzirakis, Alec McLennan, George R. Darling, Masaki Takata, Matthew J. Rosseinsky & Kosmas Prassides


See also: Editor's summary | News and Views by Iwasa

Increase in African dust flux at the onset of commercial agriculture in the Sahel region p226

Emissions of African dust increased sharply in the early 1970s, but the human contribution to land degradation and dust mobilization remains poorly understood. Now, a 3,200-year record of dust deposition off northwest Africa has been constructed. On the basis of this dust record and a proxy record for West African precipitation, it is suggested that human-induced dust emissions from the Sahel region have contributed to the atmospheric dust load for more than 200 years.

Stefan Mulitza, David Heslop, Daniela Pittauerova, Helmut W. Fischer, Inka Meyer, Jan-Berend Stuut, Matthias Zabel, Gesine Mollenhauer, James A. Collins, Henning Kuhnert & Michael Schulz


See also: Editor's summary

Early Pleistocene human occupation at the edge of the boreal zone in northwest Europe p229

Hominins colonized Eurasia fairly swiftly after they left Africa around 1.75 million years ago, although it had been thought that they did not penetrate beyond 45° N except in very warm intervals. Now, however, artefacts, fauna and flora dating back more 0.78 million years have been found in a river deposit in Norfolk, England. The findings show that humans were capable of penetrating northern Europe in cooler intervals, and will prompt a re-evaluation of the adaptations and abilities of humans at this early date.

Simon A. Parfitt, Nick M. Ashton, Simon G. Lewis, Richard L. Abel, G. Russell Coope, Mike H. Field, Rowena Gale, Peter G. Hoare, Nigel R. Larkin, Mark D. Lewis, Vassil Karloukovski, Barbara A. Maher, Sylvia M. Peglar, Richard C. Preece, John E. Whittaker & Chris B. Stringer


See also: Editor's summary | News and Views by Roberts & Grün

Loss of fish actinotrichia proteins and the fin-to-limb transition p234

One of the steps in the evolution of tetrapod limbs was the loss of the distinctive fringe of fin rays and fin folds found in the fins of fishes. It is now shown that two novel proteins, actinodin 1 and 2, are essential structural components of fin rays and fin folds in zebrafish, and are also encoded in the genomes of other teleost fish and at least one species of shark, but not in tetrapods. It is suggested that the loss of these genes may have contributed to the fin-to-limb transition in tetrapod evolution.

Jing Zhang, Purva Wagh, Danielle Guay, Luis Sanchez-Pulido, Bhaja K. Padhi, Vladimir Korzh, Miguel A. Andrade-Navarro & Marie-Andrée Akimenko


See also: Editor's summary

The genome-wide structure of the Jewish people p238

Genomic data from 14 Jewish Diaspora communities are here compared with data from 69 Old World non-Jewish populations, to investigate the demographic history of the Jewish people. Analyses shed new light on relationships between communities, reveal unappreciated genetic substructure within the Middle East, and trace the origins of most Jewish Diaspora communities to the Levant.

Doron M. Behar, Bayazit Yunusbayev, Mait Metspalu, Ene Metspalu, Saharon Rosset, Jüri Parik, Siiri Rootsi, Gyaneshwer Chaubey, Ildus Kutuev, Guennady Yudkovsky, Elza K. Khusnutdinova, Oleg Balanovsky, Ornella Semino, Luisa Pereira, David Comas, David Gurwitz, Batsheva Bonne-Tamir, Tudor Parfitt, Michael F. Hammer, Karl Skorecki & Richard Villems


See also: Editor's summary

Functionally defective germline variants of sialic acid acetylesterase in autoimmunity p243

Sialic acid acetylesterase (SIAE) is an enzyme that is involved in B-cell activation and is required to maintain immunological tolerance in mice. It is shown here that rare, inherited and functionally defective SIAE variants are associated with a variety of autoimmune diseases in humans. The study provides one of the first examples of the importance of rare genetic variants in complex diseases, such as those involving autoimmunity.

Ira Surolia, Stephan P. Pirnie, Vasant Chellappa, Kendra N. Taylor, Annaiah Cariappa, Jesse Moya, Haoyuan Liu, Daphne W. Bell, David R. Driscoll, Sven Diederichs, Khaleda Haider, Ilka Netravali, Sheila Le, Roberto Elia, Ethan Dow, Annette Lee, Jan Freudenberg, Philip L. De Jager, Yves Chretien, Ajit Varki, Marcy E. MacDonald, Tammy Gillis, Timothy W. Behrens, Donald Bloch, Deborah Collier, Joshua Korzenik, Daniel K. Podolsky, David Hafler, Mandakolathur Murali, Bruce Sands, John H. Stone, Peter K. Gregersen & Shiv Pillai


See also: Editor's summary

A random cell motility gradient downstream of FGF controls elongation of an amniote embryo p248

Most animal embryos grow through cell accumulation in a posterior growth zone, but the underlying forces are unknown. It is now proposed that posterior elongation in chicken embryos is an emergent property that arises from graded cell motility in random directions (as opposed to directed movement). This occurs in response to signalling through the fibroblast growth factor.

Bertrand Bénazéraf, Paul Francois, Ruth E. Baker, Nicolas Denans, Charles D. Little & Olivier Pourquié


See also: Editor's summary

Conserved role of intragenic DNA methylation in regulating alternative promoters p253

The methylation of DNA in 5′ promoter regions suppresses gene expression, but what is the role of DNA methylation in the bodies of genes? Here, a map of DNA methylation is generated from human brain tissue; it is found that most methylated CpG islands are within intragenic and intergenic regions, rather than within promoters. It is proposed that intragenic methylation regulates the expression of alternative gene transcripts in different tissues and cell types.

Alika K. Maunakea, Raman P. Nagarajan, Mikhail Bilenky, Tracy J. Ballinger, Cletus D’Souza, Shaun D. Fouse, Brett E. Johnson, Chibo Hong, Cydney Nielsen, Yongjun Zhao, Gustavo Turecki, Allen Delaney, Richard Varhol, Nina Thiessen, Ksenya Shchors, Vivi M. Heine, David H. Rowitch, Xiaoyun Xing, Chris Fiore, Maximiliaan Schillebeeckx, Steven J. M. Jones, David Haussler, Marco A. Marra, Martin Hirst, Ting Wang & Joseph F. Costello


See also: Editor's summary

Mechanism and regulation of acetylated histone binding by the tandem PHD finger of DPF3b p258

The lysine residues of histone proteins can be acetylated or methylated, with important effects on gene expression. Until recently the protein modules that bind acetyl-lysine have been limited to bromodomains. However, the tandem plant homeodomain (PHD) finger of human DPF3b — which is involved in gene activation — has also been reported to bind to acetylated histones. Here, three-dimensional solution structures of DPF3b offer mechanistic insight into how this protein recognizes acetylation marks.

Lei Zeng, Qiang Zhang, SiDe Li, Alexander N. Plotnikov, Martin J. Walsh & Ming-Ming Zhou


See also: Editor's summary

Measuring mechanical tension across vinculin reveals regulation of focal adhesion dynamics p263

The ability of cells to respond to physical forces is central to development and physiology, but until now it has been difficult to directly measure forces across proteins in vivo. Here, however, a calibrated biosensor is described that can measure forces with high sensitivity across specific proteins in cells. This is applied to the vinculin protein, and a regulatory mechanism is revealed in which the force applied to vinculin determines whether focal adhesions assemble or disassemble.

Carsten Grashoff, Brenton D. Hoffman, Michael D. Brenner, Ruobo Zhou, Maddy Parsons, Michael T. Yang, Mark A. McLean, Stephen G. Sligar, Christopher S. Chen, Taekjip Ha & Martin A. Schwartz


See also: Editor's summary | News and Views by Doyle & Yamada

Single-cell NF-κB dynamics reveal digital activation and analogue information processing p267

Multicellular organisms, particularly their immune systems, rely on complex cell-to-cell communication, mediated by signalling molecules that form spatiotemporal concentration gradients. Here, high-throughput microfluidic cell culture and fluorescence microscopy, together with quantitative gene expression analysis and mathematical modelling, have been used to investigate how mammalian cells respond to different levels of TNF-α and signal to NF-κB. Both digital and analogue responses are revealed.

Savaş Tay, Jacob J. Hughey, Timothy K. Lee, Tomasz Lipniacki, Stephen R. Quake & Markus W. Covert


See also: Editor's summary

Structural basis for the coupling between activation and inactivation gates in K+ channels p272

K+ channels can convert between conductive and non-conductive forms through mechanisms that range from flicker transitions (which occur in microseconds) to C-type inactivation (which occurs on millisecond to second timescales). Here, the mechanisms are revealed through which movements of the inner gate of the K+ channel KcsA trigger conformational changes at the selectivity filter, leading to the non-conductive C-type inactivated state.

Luis G. Cuello, Vishwanath Jogini, D. Marien Cortes, Albert C. Pan, Dominique G. Gagnon, Olivier Dalmas, Julio F. Cordero-Morales, Sudha Chakrapani, Benoît Roux & Eduardo Perozo


See also: Editor's summary



Cellular APOBEC3G restricts HIV-1 infection in resting CD4+ T cells p276

Ya-Lin Chiu, Vanessa B. Soros, Jason F. Kreisberg, Kim Stopak, Wes Yonemoto & Warner C. Greene




Careers Q&A

Heidi Newberg p279

Heidi Newberg, a physicist and astronomer at Rensselaer Polytechnic Institute in Troy, New York, has won a National Science Foundation grant to create the first partnership between a US team and a Chinese-led astronomy project.

Virginia Gewin


In Brief

More gifts for education p279

Giving to UK universities is on the rise.


Mothers fear for careers p279

Female scientists worry about balancing work with motherhood, study finds.


Competition concerns p279

Study of US research universities will assess their global standing.


Careers and Recruitment

Contract investigators p280

With jobs at pharmaceutical companies evaporating, working for a contract research organization is an attractive option for some. Heidi Ledford details the growing market.

Heidi Ledford




Trying to let go p284

One small step ...

Kerstin Hoppenhaus


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