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This press release is copyright Nature.
VOL.462 NO.7275 DATED 17 DECEMBER 2009
This press release contains:
· Summaries of newsworthy papers:
Cancer genomes: A smoking gun
Astronomy: A ‘super-Earth’ orbiting a nearby star
Opinion: We must confront the quake risk of geothermal energy
Climate: Learning from the past
Genetics: Parental influence on SNP effect
Seismology: Assessing fault weakness
Molecular biology: Tiny SUMOs do good work
Physics: Controlling an atom, one photon at a time
Astronomy: A dearth of small bodies
Microscopy: Electrons make light work of nanostructures
Imaging: Creating a 3D image from one look
Animal behaviour: Coots learn to recognise their chicks
And finally… War — what is it good for?
· Mention of papers to be published at the same time with the same embargo
· Geographical listing of authors
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[1] & [2] Cancer genomes: A smoking gun (AOP)
DOI: 10.1038/nature08629
DOI: 10.1038/nature08658
***This paper will be published electronically on Nature's website on 16 December at 1800 London time / 1300 US Eastern time (which is also when the embargo lifts) as part of our AOP (ahead of print) programme. Although we have included it on this release to avoid multiple mailings it will not appear in print on 17 December, but at a later date. ***
The genomes of two types of cancer are reported online this week in Nature. The findings, presented in two papers, offer a unique insight into the struggle between mechanisms of DNA mutation and repair that occur as the disease progresses.
All cancer cells carry genetic mutations that are not inherited but have accumulated as the cell progresses to disease. Mike Stratton and colleagues sequenced the genome of a melanoma cell line originally derived from the tumour of a 43-year-old man, to get a better understanding of the mutations associated with this type of skin cancer. Many of the mutations identified bear the hallmarks of DNA damage occurring as a result of ultraviolet light exposure, which is a known risk factor for melanoma.
In the second paper, Mike Stratton and colleagues sequenced the genome from a lung cancer cell line. They find mutation signatures characteristic of carcinogens present in tobacco smoke that are known to bind and mutate DNA. In both studies, the researchers find evidence that cellular DNA repair pathways have been at work, although ultimately these have not been completely successful.
The two papers provide insight into the initial causes of tumour formation, how the environment can shape cancer progression, as well as different repair pathways that try to limit the damage.
CONTACT
Mike Stratton (Wellcome Trust Sanger Institute, Cambridge, UK) Author paper [1] & [2]
Tel: +44 1223 494 757; E-mail: [email protected]
A press briefing related to these papers will take place on Tuesday 15 December at 1100 London time (GMT) at the Wellcome Trust, Gibbs Building, 215 Euston Road, London NW1 2BE. The researchers will discuss their findings followed by a Q&A session.
For more information, please contact:
Don Powell (The Wellcome Trust Sanger Institute, Cambridge, UK)
Tel: +44 1223 496 928; E-mail: [email protected]
[3] Astronomy: A ‘super-Earth’ orbiting a nearby star (pp 891-894; N&V)
A planet with radius about 2.7 times that of Earth, and about 6.6 times as massive, has been discovered orbiting a nearby star. The planet is close enough to the Earth, and its star is sufficiently small, for the planetary atmosphere to be studied using existing observatories.
Observations of stellar wobbles induced by orbiting planets have revealed a population of planets with minimum masses of between 1.9 and 10 times that of the Earth, known as ‘super-Earths’. Another method of detecting extrasolar planets, which relies on the dimming of starlight caused by a planet crossing (‘transiting’) between the star and the Earth, also yields an estimate of the planet’s radius, and thus its density. The first super-Earth with a measured radius, CoRoT-7b, has an inferred density of 5.6 kg m-3, very similar to that of the Earth (5.5 kg m-3). But CoRoT-7b orbits a star that is too distant, and too large, to allow the planet’s atmosphere to be studied.
In an attempt to find super-Earths closer to home, and orbiting smaller stars, David Charbonneau and colleagues undertook a systematic search for planets transiting 2,000 nearby M-dwarf stars. In this week’s Nature, they report the discovery of GJ 1214b, a planet that seems to be intermediate in size and composition between Earth and the ice giants of the Solar System.
CONTACT
David Charbonneau (Harvard University, Cambridge, MA, USA)
Tel: +1 617 496 6515; E-mail: [email protected]
Geoffrey Marcy (University of California, Berkeley, CA, USA) N&V author
Tel: +1 510 759 9398; E-mail: [email protected]
Opinion: We must confront the quake risk of geothermal energy (pp 848-849)
There could be a backlash against a promising alternative energy technology if its risks are not openly discussed, says Domenico Giardini in an Opinion piece in Nature this week. Enhanced geothermal system (EGS) projects involve drilling into hot rock at depths of several kilometres and pumping fluid into it, then using the hot water returning to the surface to drive energy turbines. This “brute-force approach” to geothermal energy means that engineers don't have to rely solely on areas with natural hot water reservoirs, and so can install geothermal technology more widely. Theoretically, it could supply 10% of US energy by 2050.
But pumping water into the rock causes fracturing, and can sometimes trigger significant earthquakes. This is particularly problematic if EGS projects are located near urban centres, where the heat energy is most useful, or lie near faults. An earthquake associated with an EGS project in Basel, Switzerland, for example, triggered fear and anger in the local population, and the project was halted.
The incident has led to a court case against an individual (not against the company involved), which starts next week in Switzerland, and a risk analysis published on 10 December has led to the suspension of the project.
Many energy systems carry risks, says the author, “dams can break, nuclear power plants may fail, carbon dioxide released from the oil and gas contributes to global warming, and EGS projects can create damage through induced earthquakes. The open question is whether or not society is able to find ways to balance and accept these risks.”
To allow proper utilization of EGS technology, it needs to be better studied and openly discussed, says Giardini, so that people don't panic and regulatory bodies don’t overreact to the danger.
CONTACT
Domenico Giardini (Swiss Seismological Service, ETH, Zurich, Switzerland)
Tel: +41 44 633 2610; E-mail: [email protected]
[4] Climate: Learning from the past (pp 863-867; N&V)
Global sea level was probably 8–9.4 metres above present levels during the last interglacial stage (LIG), around 125,000 years ago. The findings, published this week in Nature, indicate that previous work has underestimated the global sea level during the LIG.
The LIG was 3–5 degrees Celsius warmer at the poles than the present day and so can serve as a guideline for researchers as to what might happen if global warming continues on the path to a 1–2 degrees Celsius temperature rise. One of the many effects expected to accompany this warming is a rise in global sea level. Robert Kopp and colleagues assembled a global database of local sea level indicators and used a probabilistic statistical approach to estimate the history of global sea level rise.
The results reveal that during the LIG, global sea level was at least 6.6 metres higher than today and probably exceeded 8 metres, but is unlikely to have risen above 9.4 metres. Sea level is thought to have risen at a rate of greater than 50 centimetres per century. These findings are consistent with major melting of both the Greenland and Antarctic ice sheets and highlight the vulnerability of ice sheets to even relatively low levels of sustained global warming.
CONTACT
Robert Kopp (Princeton University, NJ, USA)
Tel: +1 609 258 2448; E-mail: [email protected]
Peter Clark (Harvard University, Cambridge, MA, USA) N&V author
Tel: +1 617 495 8391; E-mail: [email protected]
[5] Genetics: Parental influence on SNP effect (pp 868-874)
Taking into account whether a variant has been inherited from the mother or the father can significantly enhance the power of genome scans for disease susceptibility variants, a Nature study shows.
Genome-wide association studies enable researchers to identify links between genetic variation and observable traits such as disease, but until now these studies have failed to take the effect of parental origin into account. Augustine Kong and colleagues have devised a method that does just that; when applied on a genome-wide scale it uncovered five disease-related single nucleotide polymorphisms (single base pair changes) that show parental-origin-specific associations. Among the variants identified are those that associate with susceptibility type 2 diabetes and that can confer risk or protection depending on whether they have been inherited from the mother or the father.
Despite the successes, genome-wide association studies have so far yielded sequence variants that explain only a small fraction of the estimated heritability of most of the traits studied. The results presented here suggest that some of this heritability may be hidden in more complex relations between sequence variants and their inheritance patterns.
CONTACT
Augustine Kong (deCODE Genetics, Reykjavik, Iceland)
This author can be contacted through:
Edward Farmer (Media relations, deCODE Genetics)
Tel: +44 7796 010 107; E-mail: [email protected]
[6] Seismology: Assessing fault weakness (pp 907-910)
Fault weakening depends strongly on rock fabric and the distribution of weak phases within a fault zone, suggests a paper in Nature this week. The research shows that faults that contain rocks with well-developed foliation, such as the San Andreas in California, are extremely weak compared to the same rocks with a more powdered texture.
Some crustal faults seem to be extremely weak when compared to laboratory measurements of frictional strength, but scientists are still unsure why. Explanations for fault weakness include the presence of weak minerals and high fluid pressures within the fault core.
To investigate the role of fabrics in long-term fault weakening, Cristiano Collettini and colleagues conducted friction experiments on rocks from the Zuccale fault, on the island of Elba, Italy. They find that samples with well-developed foliation are much weaker than their powdered equivalents, and that fault weakness can occur in cases where weak mineral phases constitute only a small percentage of the total fault rock. Frictional sliding occurs along very fine-grained foliations composed of phyllosilicates — weak minerals such as talc — that have the effect of lubricating the fault zone.
CONTACT
Cristiano Collettini (Univerista degli Studi di Perugia, Italy)
Tel: +39 075 586 7178; E-mail: [email protected]
[7] & [8] Molecular biology: Tiny SUMOs do good work (pp 935-939; N&V)
A pathway by which a family of small proteins, known as SUMOs, may help cells to repair DNA damage is described in a pair of papers in this week’s Nature.
The reversible attachment of small ubiquitin-like modifier, or SUMO, proteins to other proteins modifies their function, influencing many cellular processes including DNA repair, protein stability and the stress response. Stephen Jackson and colleagues show that the enzymes which add SUMO onto factors involved in the repair of DNA double-strand breaks are also required for the subsequent modification of some of these proteins by ubiquitin itself. And Joanna Morris and colleagues show that addition of SUMO to the protein encoded by breast cancer susceptibility gene, BRCA1, is necessary to activate its E3 ligase function, which attaches ubiquitin to other DNA repair factors.
Together these findings define a sequential pathway of SUMO and ubiquitin modification that is required for repair of DNA damage, and suggest that the SUMO pathway may be of relevance to cancer predisposition and development.
CONTACT
Stephen Jackson (Wellcome Trust Cancer Research UK Gurdon Institute, University of Cambridge, UK) Author paper [7]
Tel: +44 1223 334102; E-mail: [email protected]
Joanna Morris (King's College London, UK) Author paper [8]
Tel: +44 20 7188 3699; E-mail: [email protected]
Simon Boulton (Cancer Research UK Clare Hall Laboratories, South Mimms, UK) N&V author
Tel: +44 1707 625 774; E-mail: [email protected]
[9] Physics: Controlling an atom, one photon at a time (pp 898-901)
Real-time feedback — the use of continuously updated information about a system to control its evolution — has been used to control the motion of a single atom in an optical trap. In an impressive extension of this technique to the edge of the quantum realm, the detection of just a few photons is sufficient to keep the atom under control.
Writing in this week’s Nature, Alexander Kubanek and colleagues describe their work on single atoms trapped in an optical cavity. In addition to the laser field that forms the trap, the system has two other lasers: a ‘probe’, which detects the presence of the atom, and an ‘actuator’, which, when it’s switched on, creates a doughnut-shaped repulsive field that pushes the atom towards the centre of the cavity.
The actuator laser gives the atom a push or leaves it alone, depending on whether the atom is moving away from or towards the centre of the trap. The information about the atom’s motion comes in the form of single photons from the probe laser, arriving at a rate of less than one every ten microseconds. Yet this is enough information to keep the atom in the trap up to four times as long as without the feedback control. The ultimate aim would be to control an atom’s trajectory with a precision limited only by Heisenberg’s uncertainty principle.
CONTACT
Alexander Kubanek (Max-Planck-Institute of Quantum Optics, Garching, Germany)
Tel: +49 89 32905 296; E-mail: [email protected]
[10] Astronomy: A dearth of small bodies (pp 895-897)
A search for sub-kilometre-sized bodies orbiting the Sun in the Kuiper belt, beyond Neptune’s orbit, has resulted in only a single detection, according to a report in this week’s Nature. The implied dearth of Kuiper belt objects with radii of a few hundred metres suggests that they are being lost to collisional erosion.
The Kuiper belt, which extends from 30 to 60 astronomical units (au) from the Sun, contains icy bodies that are remnants of the primordial Solar System. Kuiper belt objects (KBOs) smaller than a kilometre across cannot be seen with a telescope, but can be detected when they pass in front of a distant star. Previous reports of such ‘occultations’ have implied KBO abundances that are inconsistent with other lines of evidence, and at least some were contaminated by observational artefacts.
Hilke Schlichting and colleagues have searched for occultations in 4.5 years of data from the Hubble Space Telescope’s fine guidance sensors — detectors that control the telescope’s pointing by observing guide stars. Using methods most likely to detect KBOs with radii of 200–500 metres, the authors found only one occultation, by a body with a radius of about 500 metres, at about 45 au. The authors calculate that there is a deficit of KBOs in this size range, compared with extrapolations from the numbers of larger objects. They conclude that sub-kilometre-sized objects are undergoing collisional erosion — the same process that creates the debris disks observed around other stars.
CONTACT
Hilke Schlichting (University of Toronto, Canada)
Tel: +1 416 978 1775; E-mail: [email protected]
[11] Microscopy: Electrons make light work of nanostructures (pp 902-906; N&V)
A new kind of microscopy combines electrons and light to image electromagnetic fields near nanostructures, with ultrahigh resolution in both space and time. The technique, described in this week’s Nature, will allow the direct visualization of short-lived phenomena important in fields such as optical sensing and information processing.
Ahmed Zewail and colleagues call their new technique ‘photon-induced near-field electron microscopy’. As the name suggests, it combines the spatial resolution of electron microscopy with the time resolution afforded by ultrafast light pulses. A pulse of high-intensity light illuminates the nanostructure to be imaged (such as a carbon nanotube or silver nanowire), creating a transient trapped light field, or ‘evanescent wave’, close to the surface of the structure. At the same time, a pulse of electrons is focused on the structure. The electrons can gain energy from the light field, so by selecting only those electrons that have been accelerated, the microscope forms an image of the field.
Using light pulses lasting a tiny fraction of a second, and varying the time delay between the exciting light pulse and the imaging electron pulse, the team obtain snapshots of the evanescent field as it evolves on a sub-picosecond timescale. With even shorter pulses, it should be possible to follow the ultrafast dynamics of processes important in photonic and plasmonic devices.
CONTACT
Ahmed Zewail (California Institute of Technology, Pasadena, CA, USA)
Tel: +1 626 395 6536; E-mail: [email protected]
F. Javier Garcia de Abajo (CSIC Optics Institute, Madrid, Spain) N&V author
Tel: +34 653700342; E-mail: [email protected]
[12] Imaging: Creating a 3D image from one look (AOP)
DOI: 10.1038/nature08705
***This paper will be published electronically on Nature's website on 16 December at 1800 London time / 1300 US Eastern time (which is also when the embargo lifts) as part of our AOP (ahead of print) programme. Although we have included it on this release to avoid multiple mailings it will not appear in print on 17 December, but at a later date. ***
Capturing a three-dimensional (3D) view of an object from a single measurement is possible, according to a study published this week in Nature. This potentially provides for a much simpler method of acquiring 3D images of objects, and could find broad applications in physical and life sciences.
Traditionally, multiple measurements of an object are needed to determine its 3D structure. This approach is used in confocal microscopy and crystallography.
Jianwei Miao and colleagues present a new 3D imaging method, called ankylography, which, under certain conditions, only requires a single exposure. The approach uses a single beam of X-rays, and measures the diffraction pattern on a spherical surface centred on the sample. Through the use of simulations, the authors show that the pattern on the spherical surface can provide the necessary structural information to produce successfully the 3D image of the sample.
To use ankylography readily in physical and life sciences, there needs to be further advancements in detector technology. Miao and colleagues believe that such strides in the technology are not far off.
CONTACT
Jianwei Miao (University of California, Los Angeles, CA, USA)
Tel: +1 310 206 2645; E-mail: [email protected]
[13] Animal behaviour: Coots learn to recognise their chicks (AOP)
DOI: 10.1038/nature08655
***This paper will be published electronically on Nature's website on 16 December at 1800 London time / 1300 US Eastern time (which is also when the embargo lifts) as part of our AOP (ahead of print) programme. Although we have included it on this release to avoid multiple mailings it will not appear in print on 17 December, but at a later date. ***
American coots use their first-hatched chick as a template to identify intruders among their offspring, reveals a Nature paper this week. This simple method could explain why coots are unable to recognize parasitic offspring after the eggs have hatched.
Bruce Lyon and Daizaburo Shizuka observed American coot nests on several wetlands in British Columbia between 1987–1990 and 2005–2008, They show that American coots, Fulica americana, can recognize and reject parasitic chicks in their brood by using learned cues, despite the fact that the hosts and the brood parasites are of the same species.
Because coot eggs hatch earlier than their avian parasite eggs, coots are able to successfully eliminate the impostors by comparing them to their first-hatched chick. When impostor eggs hatch first, however, coots recognise the parasitic chick as their own and turn against their real offspring. The authors also challenge the theory that coots only imprint on their first breeding attempt, showing that imprinting errors are not final and coots relearn to identify their chicks annually.
CONTACT
Bruce Lyon (University of California, Santa Cruz, CA, USA)
Tel: +1 408 459 4143; E-mail: [email protected]
Daizaburo Shizuka (University of California, Santa Cruz, CA, USA)
Tel: +1 831 459 2998; E-mail: [email protected]
[14] And finally… War — what is it good for? (pp 911-914)
The size and timing of violent events within different human insurgent conflicts exhibit many similarities, reports a paper in Nature this week. The study puts forward a model that can help to quantify collective violent activity in humans and make a connection between human insurgency, global terrorism and ecology. This model could be used to help predict future violent events faced by society and potentially prevent their rapid escalation.
Until now collective human violence has been a neglected topic, despite being one of the most basic forms of human behaviour. This may be because political, ideological, cultural, historical and geographical influences make conflict one of the ‘messiest’ of all human activities to analyse. Previous studies have looked at size distributions of casualties in wars and terrorist attacks from the early 19th to the late 20th centuries, but universal patterns across wars with regards to size or timing within conflict events have barely been explored.
In a study spanning several years, Neil Johnson and colleagues looked at insurgence events, such as those in Afghanistan and previously Colombia, and note that they show remarkable statistical similarities in relation to power laws and timing. The model used to quantify this data challenges traditional theories about insurgencies that are based on rigid hierarchies and networks. It also hints at a possible link between collective human behaviour in violent and non-violent settings.
CONTACT
Neil Johnson (University of Miami, Coral Gables, FL, USA)
Tel: +1 305 333 6920; E-mail: [email protected]
ALSO IN THIS ISSUE…
[15] Growth landscape formed by perception and import of glucose in yeast (pp 875-879)
[16] Division and apoptosis of E2f-deficient retinal progenitors (pp 925-929)
[17] E2F1-3 Switch from Activators in Progenitor Cells to Repressors in Differentiating Cells (pp 930-934)
ADVANCE ONLINE PUBLICATION
***This paper will be published electronically on Nature's website on 16 December at 1800 London time / 1300 US Eastern time (which is also when the embargo lifts) as part of our AOP (ahead of print) programme. Although we have included it on this release to avoid multiple mailings it will not appear in print on 17 December, but at a later date. ***
[18] Identification of sister chromatids by DNA template strand sequences
DOI: 10.1038/nature08644
GEOGRAPHICAL LISTING OF AUTHORS…
The following list of places refers to the whereabouts of authors on the papers numbered in this release. For example, London: 4 - this means that on paper number four, there will be at least one author affiliated to an institute or company in London. The listing may be for an author's main affiliation, or for a place where they are working temporarily. Please see the PDF of the paper for full details.
CANADA:
Toronto: 10, 16, 17
Vancouver: 18
COLOMBIA
Bogota: 14
FRANCE
Grenoble: 3
GERMANY
Garching: 9
ICELAND
Reykjavik: 5
ISRAEL
Jerusalem: 10
Rehovot: 10
Tel-Aviv: 10
ITALY
Perugia: 6
Roma: 6
Siena: 6
NETHERLANDS
Leiden: 2
SWITZERLAND
Geneva: 3
UNITED KINGDOM
Cambridge: 1, 2, 3, 5, 7, 8, 14, 15, 17
Glasgow: 8, 17
Hinxton: 1, 2
Little Chesterford: 2
London: 8, 14
Sutton: 1, 2
Warrington: 1
UNITED STATES OF AMERICA
California
Davis: 16
Foster City: 1
Hayward: 2
Los Angeles: 12
Pasadena: 10, 11
San Diego: 2
Santa Cruz: 13
Colorado
Boulder: 12
Florida
Coral Gables: 14
Maryland
Baltimore: 10
Greenbelt: 10
Massachusetts
Beverly: 1
Boston: 17
Cambridge: 2, 4
New Jersey
Princeton: 4
Ohio
Columbus: 16, 17
Oxford: 17
Pennsylvania
Pittsburgh: 17
University Park: 6
Texas
Dallas: 1
Denton: 12
PRESS CONTACTS…
From North America and Canada
Neda Afsarmanesh, Nature New York
Tel: +1 212 726 9231; E-mail: [email protected]
From Japan, Korea, China, Singapore and Taiwan
Mika Nakano, Nature Tokyo
Tel: +81 3 3267 8751; E-mail: [email protected]
From the UK/Europe/other countries not listed above
Jen Middleton, Nature London
Tel: +44 20 7843 4502; E-mail [email protected]
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