2 June 2006 | $10 15 30 45 15 30 45 15 30 45 1.7 kb Seconds / kb Herculase ® II Enzyme Phusion ™ /iProof ™ Pwo SuperYield Our Herculase ® II Fusion DNA Polymerase produces superior yield in as short as 15 second/kb extension time. Need More Information? Give Us A Call: Stratagene USA and Canada Order:800-424-5444 x3 Technical Service:800-894-1304 x2 Stratagene Japan K.K. Order: 3-5821-8077 Technical Service: 3-5821-8076 Stratagene Europe Order: 00800-7000-7000 Technical Service: 00800-7400-7400 A MPLIF I C A T I ON CELL BI O L O G Y C L ONI N G MIC R O A RRA Y S N U C L E I C A C I D A N A L Y S I S PROTEIN FUNCTION & A N A LY S I S QU A NTI T A T I V E P C R S O F T WA R E S O L U T I ONS Ask us about these great products: www.stratagene.com PfuUltra ™ II Fusion HS DNA Polymerase 40 rxn 600670 Herculase ® II Fusion DNA Polymerase 40 rxn 600675 Our PfuUltra ™ II Fusion HS DNA Polymerase offers the highest fidelity. Error rates were determined by the lacI fidelity assay. 0.00 5.00 10.00 15.00 20.00 25.00 PfuUltra ™ II Enzyme Herculase ® II Enzyme Phusion ™ / iProof ™ DeepVent ® Vent ® Pfx/KOD Pfx50 ™ Taq Enzyme Accuracy (x10 5 ) Our next generation of high fidelity Pfu -based fusion enzymes sets a new standard in high fidelity PCR performance. Engineered for industry-leading fidelity plus 12x enhanced processivity, our new PfuUltra ™ II Fusion HS DNA Polymerase and Herculase ® II Fusion DNA Polymerase deliver superior yield, excellent reliability, and faster overall run times. Our new breed is the center of attention. PfuUltra ™ II enzyme for highest fidelity • Herculase ® II enzyme for superior yield Purchase of this product is accompanied by a license under the foreign counterparts of U.S. Patents Nos. 4,683,202, 4,683,195 and 4,965,188 for use in the polymerase chain reaction (PCR) process, where such process is covered by patents, in conjunction with a thermal cycler whose use in the automated performance of the PCR process is covered by the up-front license fee, either by paymentto Applied Biosystems or as purchased, i.e., an authorized thermal cycler. U.S. Patent Nos. 6,734,293, 6,489,150, 6,444,428, 6,379,553, 6,333, 165, 6,183,997, 5,948,663, 5,866,395, 5,545,552 and patents pending PfuUltra ™ is a trademark of Stratagene in the United States. Herculase ® is a registered trademark of Stratagene in the United States. Deep Vent ® and Vent ® are registered trademarks of New England BioLabs. iProof ™ is a trademark of BioRad Laboratories. Phusion ™ is a trademark of Finnzymes Oy. Pfx50 ™ is a trademark of Invitrogen. For more information contact us at: www.cambr ex.com U.S. 800-638-81 74 |Europe 32 (0) 87 3 2 16 11 For Research Use Only. Not for Use in Diagnostic Procedures. CambrexBio Science Walkersville,Inc. 8830 Biggs FordRoad | Walkersville, MD 21793 Cambrex, the source for Clonetics ® and Poietics ™ Cell Systems, BioWhittaker ™ Classical Media, SeaPlaque ® and NuSieve ® Agarose, and PAGEr ® Precast Gels. Primary Cells for Pioneering Research Clonetics ® Lung Lymphatic and Blood Endothelial Cells Lung Lymphatic (LEC) and Lung Blood (BEC) Microvascular Endothelial Cell Systems have a higher purity for better experi- mental results in your angiogenesis, pulmonary, vascular and lymphatic research. • Cells are derived from normal human lung tissue and deliver >90% purity. • No more mixed endothelial cultures with unknown LEC:BEC ratios. • Optimal performance guaranteed with existing EGM-2MV media kit. • Cleaner, more consistent results with less cell variability. Poietics ™ Normal Peripheral Blood Leukopaks Normal Peripheral Blood Leukopak is a bag of fresh human blood cells collected from normal peripheral blood by automated apheresis. Each leukopak contains a mixture of monocytes, lymphocytes, platelets, plasma, and red cells. • Leukopaks are monocyte enriched. • Standard leukopak contains total white cell count of >60 million per ml and volume is >100 ml. • All donors are screened for general health, and test negative for HIV-1, hepatitis B & C. • Leukopaks with special donor characteristics are available, such as tetanus-boosted, CMV negative, diabetic, EBV and PMN enriched. PrimaryLeader PrimaryChoice PrimaryResearch Primary Source GE Healthcare HiTrap ™ columns give you pure proteins with less effort. They come prepacked with the widest choice of media, ensuring results you can depend on in a broad range of applications, and the highest level of convenience. But we’re never content to stand still. We constantly strive for new innovations for tomorrow’s research and drug development. And thanks to our technological achievements and global presence, we’re able to help you turn your scientific ideas into reality – bringing science to life and helping transform healthcare. We call it Life Science Re-imagined. Discover how HiTrap columns can help power your protein purification. Visit www.gehealthcare.com/life Faster protein purification? It’s not rocket science. GE Healthcare Bio-Sciences AB, a General Electric Company. Björkgatan 30, 751 84 Uppsala, Sweden. © 2006 General Electric Company - All rights reserved. GE05-06 www.dowellstubbs.com www.sciencemag.org SCIENCE VOL 312 2 JUNE 2006 1265 CONTENTS CONTENTS continued >> NEWS OF THE WEEK University Bids to Salvage Reputation After Flap 1288 Over Logging Paper Bristol-Myers Ends No-Strings Grants 1289 Over Protests, U.K. Union Endorses Boycott of 1289 Israeli Academics India Opens Universities to More Underprivileged 1291 Students SCIENCESCOPE 1291 Ancient Figs Push Back Origin of Plant Cultivation 1292 >> Report p. 1372 Court Revives Georgia Sticker Case 1292 Tools Link Indonesian ‘Hobbits’ to Earlier 1293 Homo Ancestor Spain Aims to Lure Systems Biologists to a Place 1295 in the Sun Senate Bill Would Boost High-Tech Workforce 1295 NEWS FOCUS Stormy Skies for Polar Satellite Program 1296 South Korea Picks Up the Pieces 1298 A Surprising Stellar Nursery 1301 Aging Atom Smasher Runs All Out in Race for 1302 Most Coveted Particle Genes Commute to Factories Before They Start Work 1304 Neutrino Hunters Plan a Voyage to the Bottom 1305 of the Sea DEPARTMENTS 1271 Science Online 1273 This Week in Science 1279 Editors’ Choice 1282 Contact Science 1285 NetWatch 1287 Random Samples 1307 Newsmakers 1407 New Products 1408 Science Careers COVER The near-Earth asteroid 25143 Itokawa as imaged from the Hayabusa spacecraft. The view is from the direction of the longest axis (535 m; the other axes are 294 and 209 m). The surface is covered with a great number of large boulders. See the special section beginning on page 1327. Image: Japan Aerospace Exploration Agency EDITORIAL 1277 The Billion-Ton Biofuels Vision by Chris Somerville Volume 312, Issue 5778 INTRODUCTION The Falcon Has Landed 1327 PERSPECTIVE Adventures in Near-Earth Object Exploration 1328 E. Asphaug REPORTS The Rubble-Pile Asteroid Itokawa as Observed by Hayabusa 1330 A. Fujiwara et al. Near-Infrared Spectral Results of Asteroid Itokawa 1334 from the Hayabusa Spacecraft M. Abe et al. X-ray Fluorescence Spectrometry of Asteroid Itokawa by Hayabusa 1338 T. Okada et al. Detailed Images of Asteroid 25143 Itokawa from Hayabusa 1341 J. Saito et al. Mass and Local Topography Measurements of Itokawa by Hayabusa 1344 S. Abe et al. Pole and Global Shape of 25143 Itokawa 1347 H. Demura et al. Touchdown of the Hayabusa Spacecraft at the Muses Sea 1350 on Itokawa H. Yano et al. SPECIAL SECTION Hayabusa at Asteroid Itokawa 1296 Enter the world of reliable gene silencing and geneexpression analysis! Genomewide solutions from QIAGEN include potent, specific siRNAs and matching, ready-to-use, validated primer sets for SYBR ® Green based real-time RT-PCR assays. Benefits include: ■ Easy online access to RNAi and gene expression solutions at GeneGlobe ■ siRNAs and RT-PCR assays for theentire human, mouse, and rat genomes ■ RT-PCR assays for arabidopsis, drosophila, dog, and chicken For up-to-date trademarks anddisclaimers, see www.qiagen.com . RNAiGEXGeneGlobe0106S1WW ©2006 QIAGEN, all rights reserved. Systems Biology — RNAi and Gene Expression Analysis GeneGlobe — the world’s largest database of matching siRNAs and RT-PCR assays WWW. QIA G E N . C OM For matched siRNAs and real-time RT-PCR assays you can rely on, go to www.qiagen.com/GeneGlobe ! New 1000 E+1 Cycle 15 20 25 35 1000 30 1000 E–1 Untransfected Transfected with PRKCA siRNA Reliable quantification after knockdown Visit www.qiagen.com/GeneGlobe www.sciencemag.org SCIENCE VOL 312 2 JUNE 2006 1267 CONTENTS continued >> SCIENCE EXPRESS www.sciencexpress.org DEVELOPMENTAL BIOLOGY Hox Control of Organ Size by Regulation of Morphogen Production and Mobility M. A. Crickmore and R. S. Mann The small size of the Drosophila hindwing results from spatial restriction of the critical morphogen by binding proteins not expressed in the larger forewing. 10.1126/science.1128650 PLANT SCIENCE Hierarchical Action and Inhibition of Plant Dicer-Like Proteins in Antiviral Defense A. Deleris et al. RNA silencing blocks infection and long-distance transport of infecting viruses in Arabidopsis. 10.1126/science.1128214 ASTRONOMY The Spiral Structure of the Outer Milky Way in Hydrogen E. S. Levine, L. Blitz, C. Heiles Imaging the distribution and density of atomic hydrogen in the Milky Way shows that our galaxy forms a multi-armed spiral that is not symmetric about its axis. 10.1126/science.1128455 CHEMISTRY An Octahedral Coordination Complex of Iron(VI) J. F. Berry et al. A complex in which iron is in the rare +6 oxidation state and triple bonded to nitrogen is stable to 77 kelvin and can serve as a powerful oxidant upon warming. 10.1126/science.1128506 CONTENTS TECHNICAL COMMENT ABSTRACTS CELL BIOLOGY Comment on “HST2 Mediates SIR2-Independent 1312 Life-Span Extension by Calorie Restriction” M. Kaeberlein et al. full text at www.sciencemag.org/cgi/content/full/312/5778/1312b Response to Comment on “HST2 Mediates SIR2-Independent Life-Span Extension by Calorie Restriction” D. W. Lamming et al. full text at www.sciencemag.org/cgi/content/full/312/5778/1312c BREVIA MATERIALS SCIENCE Direct Determination of Local Lattice Polarity 1354 in Crystals K. A. Mkhoyan, P. E. Batson, J. Cha, W. J. Schaff, J. Silcox A scanning transmission electron microscope reveals atomic-level columns of nitrogen and their polarity in an aluminum nitride with sub-angstrom resolution. RESEARCH ARTICLE NONHUMAN GENETICS Metagenomic Analysis of the Human Distal 1355 Gut Microbiome S. R. Gill et al. Sequencing the trillions of microbes in the human colon identifies genes involved in the digestion of plant carbohydrates, the fermentation of fiber, and vitamin synthesis. REPORTS PHYSICS Conductance Quantization at a Half-Integer 1359 Plateau in a Symmetric GaAs Quantum Wire R. Crook et al. Electron spins in a thin gallium-arsenide wire spontaneously organize in the absence of a magnetic field, producing a new ferromagnetic phase useful in spintronics. LETTERS New Scientific Society in Nicaragua J. A. Huete-Pérez 1309 Examining Knowledge of Geometry K. Wulff; R. M. Delson Response S. Dehaene et al. Ecological Revitalization of Chinese Villages E. C. Ellis Stereotype Threat: A Clarification L. J. Stricker Response D. Lewis CORRECTIONS AND CLARIFICATIONS 1312 BOOKS ET AL. 1491 New Revelations of the Americas Before Columbus; 1313 Ancient Americans Rewriting the History of the New World C. C. Mann, reviewed by D. R. Snow The Sensory Hand Neural Mechanisms of Somatic 1314 Sensation V. B. Mountcastle, reviewed by C. G. Gross and A. A. Ghazanfar POLICY FORUM Finding Criminals Through DNA of Their Relatives 1315 F. R. Bieber, C. H. Brenner, D. Lazer PERSPECTIVES Linking Nutrition and Tissue Growth 1317 P. Léopold and S. Layalle >> Report p. 1385 Unfallen Grains: How Ancient Farmers Turned Weeds 1318 into Crops J. Doebley >> Report p. 1392 Exploring Other Worlds to Learn More About Our Own 1319 I. C. F. Müller-Wodarg >> Report p. 1366 Align in the Sand 1320 D. Grünbaum >> Report p. 1402 Toward Efficient Hydrogen Production at Surfaces 1322 J. K. Norskov and C. H. Christensen Aerosols, Clouds, and Climate 1323 D. Rosenfeld >> Report p. 1375 Accelerating Customers' Success through Leadership in Life Science, High Technology and Service SIGMA-ALDRICH CORPORATION • BOX 14508 • ST. LOUIS • MISSOURI 63178 • USA Assistance! At Sigma, we’re pulling with you sigma.com/assaykits For a change think inside the box and choose the assay kit that truly facilitates your cell biology research. You have better ways to spend your time than developing and validating cell biology assays. With more than 100 kits available, let our assay kits do the work for you. Inside each kit is everything you need to make assaying simpler than ever before. Plus, we have technical experts on hand worldwide to further assist in getting the very best from your research. Our assay kits are just one of the many cell biology solutions that we offer to more than a million scientists every day. From the widest selection of products to the best technical support, we’re the research partner of choice around the world. So when you need assistance in finding an easier way to assay, count on Sigma. SCIENCE @ WORK . Sea DEPARTMENTS 1271 Science Online 1273 This Week in Science 1279 Editors’ Choice 1282 Contact Science 1285 NetWatch 1287 Random Samples 1307 Newsmakers 1407 New Products 1408 Science Careers COVER The. after knockdown Visit www.qiagen.com/GeneGlobe www.sciencemag.org SCIENCE VOL 312 2 JUNE 2006 1267 CONTENTS continued >> SCIENCE EXPRESS www.sciencexpress.org DEVELOPMENTAL BIOLOGY Hox Control. why not discover how you can create your RNAi advantage. www.sciencemag.org SCIENCE VOL 312 2 JUNE 2006 1271 ONLINE SCIENCENOW www.sciencenow.org DAILY NEWS COVERAGE Thumbs Up for Leech Therapy