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Nature press release for 19 July issue

July 19, 2001

[412352] LIFELINES: TRIPLE CHECK (pp352-355; N&V)
There are currently two well established main checkpoints in cell division. In this week’s Nature, researchers report a new type of checkpoint in yeast. This finding could lead to a better understanding of how cells form different tissues.
For cell division to work, each daughter cell must get one complete set of chromosomes. To achieve this, the chromosomes attach to a framework of proteins called the spindle, which aligns them and pulls them to opposite poles of the cell.
The newly discovered checkpoint ensures that the spindle forms in the correct position by monitoring another network of filaments, made of the protein actin, that criss-cross the cell, Jonathon Millar of the National Institute for Medical Research, London, and colleagues have found. Variations in the functioning of this checkpoint may lead cells to divide asymmetrically — an important factor in development — and its breakdown may induce cells to become cancerous.
Yukinobu Nakaseko and Mitsuhiro Yanagida of Kyoto University discuss the broad implications of the finding in an accompanying News and Views article.
CONTACT:
Jonathon Millar tel +44 20 8959 3666, e-mail jmillar@nimr.mrc.ac.uk
Mitsuhiro Yanagida tel +81 75 753 4205, e-mail yanagida@kozo.biophys.kyoto-u.ac.jp

[412295] PHYSICS: MAGNETISM BRINGS ABOUT A ‘BOSENOVA’ (pp295-299)
The fifth form of matter has physicists scratching their heads again. Using magnetic fields, Elizabeth A. Donley of the University of Colorado, Boulder, and colleagues caused a Bose–Einstein condensate — the weird quantum sibling of solids, liquids, gases and plasmas — of rubidium-85 atoms to shrink and then undergo a sudden explosion of atoms outwards. This latter phenomenon is known in the quantum-physics trade as a ‘bosenova’ or ‘supernova in a bottle’.
“Although the system would seem to be simple and well characterized”, say the researchers, “our measurements reveal many phenomena that challenge theoretical models”. A Bose–Einstein condensate is created when a group of ultracold atoms become virtually indistinguishable from one another.
CONTACT:
Elizabeth A Donley tel +1 303 492 4718, e-mail donley@jilau1.colorado.edu

[412300] LIFELINES: TO B OR NOT TO B (pp300-307; N&V)
Little is known about the factors that control a critical step in antibody production, the differentiation of mature activated B cells into antibody-secreting plasma cells. This week, Laurie H. Glimcher of Harvard School of Public Health, and colleagues, show that a protein called ‘XBP-1’ seems to precipitate B-cell differentiation.
The immune system has two lines of defence against foreign invaders. T cells kill virally infected or malignant cells, and antibodies are released into the bloodstream by plasma cells, which are specialized B cells that no longer divide. Antibodies are involved in many autoimmune diseases, so studies of autoimmunity would benefit greatly from a better understanding of plasma cells.
“The discovery of a protein required for the production of plasma cells will give immunologists a better idea of how they develop,” says Kathryn Calame of Columbia University College of Physicians and Surgeons, New York, in an accompanying News and Views article.
CONTACT:
Laurie H Glimcher tel +1 617 432 0622, e-mail lglimche@hsph.harvard.edu
Kathryn Calame tel +1 212 305 3504, e-mail klc1@columbia.edu

[412255] POLICY: SCIENCE IN ITALY (p255; 264-265)
Italy is a major economic power, but it underachieves in research. A News Feature and Editorial examine attempts to reform the nation’s scientific institutions - and consider their prospects under the new government of Silvio Berlusconi.
(The Editorial will not be available on the press site until Tuesday.)

[412308] SPACE: AHEAD IN THE CLOUDS (pp308-310; N&V)
The discovery of a large cloud of cold atomic hydrogen goes against the conventional wisdom that the cold interstellar medium is mainly molecular hydrogen.
Interstellar clouds are immense collections of dust and gas floating between the stars in the Milky Way (and other galaxies). These clouds come in different types, classified according to their temperature and content. Now Lewis B. G. Knee of the Dominion Radio Astrophysical Observatory, National Research Council of Canada, British Columbia, and colleagues have discovered a new kind of cloud in data from the Canadian Galactic Plane Survey.
“If the rate of these atomic cloud discoveries continues apace, astronomers will have to reconsider some of their ideas about the structure and evolution of galaxies,” comments John M. Dickey of the University of Minnesota, Minneapolis, in an accompanying News and Views article.
CONTACT:
Lewis B G Knee tel +1 250 490 4318, e-mail lewis.knee@nrc.ca
John M. Dickey tel +1 612 624 2895, e-mail john@astro.umn.edu

[412293] RELICS: DATE OF FLOOD (pp293-294)
The ancient Egyptian cities of Herakleion and Eastern Canopus — which now lie under the sea — were probably drowned by the Nile, report researchers in this week’s Nature. Using archaeological and geological evidence, Jean-Daniel Stanley of the National Museum of Natural History, Smithsonian Institution, Washington DC, and colleagues date the inundation to AD 741 or 742.
The flood at this time was one metre higher than normal flood levels. And the youngest coins recovered from Eastern Canopus date to around the same time. The researchers believe that the flood caused riverbanks near Canopus to fail, and the channel of the Nile to shift. The sediments in the seabed of Abu Qir Bay, which covers the two towns 6–7 metres below, show a layer of mud containing the remains of freshwater plants and animals.
CONTACT:
Jean-Daniel Stanley tel +1 202 357 2310, e-mail stanley.daniel@nmnh.si.edu

[412316] PHYSICS: STRIKING BEHAVIOUR FROM COLD IRON (pp316-318; N&V)
Superconductivity and ferromagnetism have often been considered mutually exclusive. But this week in Nature, Katsuya Shimizu of Osaka University, Japan, and colleagues report that iron, the ultimate ferromagnet, superconducts — albeit in its non-magnetic state at high pressure and at temperatures below 2 K. Calculations had predicted this behaviour, but Shimizu’s team are the first to show it experimentally.
Superconductivity occurs in conventional non-magnetic metals when they are cooled to temperatures low enough that their conduction electrons pair up and flow without resistance. In addition to having zero electrical resistance, superconductors have the ability to expel magnetic fields from their interior. So it has long been thought that superconductivity and ferromagnetism are incompatible, especially as tiny magnetic impurities can destroy superconductivity in non-magnetic materials. Despite these widespread beliefs, superconductivity and ferromagnetism can mix when the magnetization is small, as Shimizu’s team demonstrate.
In an accompanying News and Views article, S. S. Saxena and Peter B. Littlewood of the Cavendish Laboratory, Cambridge, UK, discuss the background and ramifications of this work.
CONTACT:
Katsuya Shimizu tel +81 6 6850 6446, e-mail kshimizu@mp.es.osaka-u.ac.jp
Peter B. Littlewood tel +44 1223 339991, e-mail pbl21@phy.cam.ac.uk

[412331] EVOLUTION: SURVIVAL OF THE FLATTEST (pp331-333)
Digital organisms are computer programs obeying the laws of mutation and natural selection. Claus O. Wilke of the California Institute of Technology, Pasadena, and colleagues use them to show in this week’s Nature that as genetic mutation rate increases, competition — instead of favouring the highest replication rate as it usually does — switches to favouring a lower replication rate. Digital organisms with a lower replication rate had lower fitness but occupied flatter areas of the fitness surface, and so were better protected against mutations.
        This work demonstrates how digital organisms — a controversial study tool in evolutionary biology — can shed light on the interplay between two of the most basic processes of evolution: mutation and natural selection.
For a visualization of these organisms growing and multiplying, visit www.dllab.caltech.edu/pubs/nature01.
CONTACT:
Claus O Wilke tel +1 626 395 2338, e-mail wilke@caltech.edu

[412321] EARTH: POTENTIAL POISONS IN THE PAN (pp321-324)
Teflon, the coating used in non-stick frying pans, and similar compounds degrade to produce potentially toxic chemicals, as Canadian researchers show in this week’s Nature. Their findings call into question continued use of such chemicals, whose long-term environmental effects are unknown.
Teflon and other fluorinated polymers are used in ovens, non-stick cooking utensils and combustion engines — yet heating creates a cocktail of breakdown products, Scott Mabury of the University of Toronto, and colleagues, now show. These include the highly persistent compounds trifluoroacetate (TFA), which is mildly toxic to plants, longer-chain perfluorocarboxylates, which accumulate in animal tissues, plus small quantities of ozone-destroying chlorofluorocarbons (CFCs).
With limited knowledge of their lasting effects, their continued use could become an issue. “We’re using compounds that will persist in the environment for very long periods of time,” says Mabury.
CONTACT
Scott Mabury tel + 416 978 1780, e-mail smabury@chem.utoronto.ca

[412334] MEDICINE: HIV NEWS AND PLEA (pp334-338; 271-272)
A study of mother-to-child HIV-1 transmission published this week in Nature shows that an important virus escape variant, no longer recognized by the host immune response, is maintained when the virus is transmitted. This occurs, suggest Bruce D. Walker of Harvard Medical School, Boston, Massachusetts, and colleagues, despite the absence of selection pressure in the offspring.
The finding provides evidence that these mutations could accumulate as the virus spreads through the population, with potentially important implications for pathogenesis of the infection and vaccine design.
Also in this week’s Nature, an international representation of senior AIDS experts submits a plea to the 20 July G8 summit to prioritize spending on AIDS research. The summit may be the last chance to increase the Global Fund on AIDS to the size required to do the job — and to get it up and running this year, they say.
Without adequate financing, the fund will fail — leaving it another year will cost countless lives. Donor and recipient countries now agree that the fund must be sustainably financed, be properly structured, have a clear mandate, and be independent to decide on the distribution of funds. But consensus is meaningless without enough money, they write. As things stand, only US$845 million is pledged of the US$8–10 billion needed for the fund to accomplish its mission — an order-of-magnitude increase in donations by the G8 is needed urgently.
CONTACT:
Bruce D Walker tel +1 617 724 8332, e-mail bwalker@helix.mgh.harvard.edu
RE AIDS FUNDING:
Peter Hale (Necker Institute, Paris, available from Friday 13th) tel +33 1 40 61 56 16 / 53 10, mobile +33 6 85 94 02 18, hale@necker.fr
Michael Merson (Dean, Yale University School of Public Health) tel +1 203 785 2867 (office), +1 203 389 8241 (home), e-mail michael.merson@yale.edu
Thomas Quinn (Johns Hopkins University) tel +1 410 955 7635 / 3151 (office), +1 301 807 9831 (mobile), e-mail tquinn@jhmi.edu

[412341] LIFELINES: ALL CHANGE (pp341-346]
A natural mechanism for fine-tuning our immune response to disease may underlie the development of a form of non-Hodgkin’s lymphoma affecting B cells, report Riccardo Dalla-Favera at Columbia University in New York and colleagues in this week’s Nature.
While they are developing, regions of the DNA of antibody-producing B cells undergo a process called ‘hypermutation’ to generate a range of antibody types. Dalla-Favera’s group screened the DNA of B cells from over 100 patients with ‘B-cell diffuse large-cell’ non-Hodgkin’s lymphoma. They found that this hypermutation mechanism has escaped the confines of the region that codes for antibodies, and now causes hypermutation of other genes — including four genes known to be associated with cancerous B cells. Hypermutation of these genes is likely to lead to the formation of this specific type of B-cell lymphoma, the researchers conclude.
CONTACT:
Riccardo Dalla-Favera tel +1 212 304 7380, e-mail rd10@columbia.edu

[412294] …AND FINALLY: GORILLAS MAKE A SPLASH (p294)
Male western lowland gorillas (Gorilla gorilla gorilla) intimidate their rivals with displays of water splashing, report researchers in this week’s Nature. This is the first time that wild primates have been seen to use water to communicate.
Richard Parnell of the Wildlife Conservation Society, New York, and Hannah Buchanan-Smith of the University of Stirling, UK, studied gorillas in the Congo. The animals here visit open swampland, where such displays are visible from a long way off.
The researchers saw male gorillas create these spectacles by jumping into pools or by spraying huge plumes of water with their hands. Displays were made exclusively by males, and were usually directed at other males. However, the closely related and better understood mountain gorillas don’t send signals in this way, perhaps because long-range visual impact is unnecessary in their more confined forest environment.
CONTACT:
Richard Parnell, tel +44 01786 466373, e-mail r.j.parnell@stir.ac.uk


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