Quadruple DNA helix discovered in human cells – life – 20 January 2013 – New Scientist

Sixty years after James Watson and Francis Crick established that DNA forms a double helix, a quadruple-stranded DNA helix has turned up.

Quadruple helices that intertwine four, rather than two, DNA strands had been made in the laboratory, but were regarded as curiosities as there was no evidence that they existed in nature. Now, they have been identified in a range of human cancer cells.

The four-stranded packages of DNA, dubbed G-quadruplexes, are formed by the interaction of four guanine bases that together form a square. They appear to be transitory structures, and were most abundant when cells were poised to divide. They appeared in the core of chromosomes and also in telomeres, the caps on the tips of chromosomes that protect them from damage.

Because cancer cells divide so rapidly, and often have defects in their telomeres, the quadruple helix might be a feature unique to cancer cells. If so, any treatments that target them will not harm healthy cells.

“I hope our discovery challenges the dogma that we really understand DNA structure because Watson and Crick solved it in 1953,” says Shankar Balasubramanian of the University of Cambridge, UK.

via Quadruple DNA helix discovered in human cells – life – 20 January 2013 – New Scientist.

Genome Reveals Comb Jellies’ Ancient Origin: Scientific American

Animals evolved gradually, from the lowly sponge to the menagerie of tentacled, winged and brainy creatures that inhabit Earth today. This idea makes such intuitive sense that biologists are now stunned by genome-sequencing data suggesting that the sponges were preceded by complex marine predators called comb jellies.

via Genome Reveals Comb Jellies’ Ancient Origin: Scientific American.

Largest-Known Spiral Galaxy 5 times as big as Milky Way

The spectacular barred spiral galaxy NGC 6872 has ranked among the biggest stellar systems for decades. Now a team of astronomers from the United States, Chile and Brazil has crowned it the largest known spiral, based on archival data from NASA’s Galaxy Evolution Explorer (GALEX) mission, which has since been loaned to the California Institute of Technology in Pasadena.

Measuring tip-to-tip across its two outsized spiral arms, NGC 6872 spans more than 522,000 light-years, making it more than five times the size of our Milky Way galaxy.

via NASA’s Galex Reveals the Largest-Known Spiral Galaxy – NASA Jet Propulsion Laboratory.

Evidence for Asteroid Belt Around Vega

Astronomers have discovered what appears to be a large asteroid belt around the star Vega, the second brightest star in northern night skies. The scientists used data from NASA’s Spitzer Space Telescope and the European Space Agency’s Herschel Space Observatory, in which NASA plays an important role.

The discovery of an asteroid belt-like band of debris around Vega makes the star similar to another observed star called Fomalhaut. The data are consistent with both stars having inner, warm belts and outer, cool belts separated by a gap. This architecture is similar to the asteroid and Kuiper belts in our own solar system.

What is maintaining the gap between the warm and cool belts around Vega and Fomalhaut? The results strongly suggest the answer is multiple planets. Our solar system’s asteroid belt, which lies between Mars and Jupiter, is maintained by the gravity of the terrestrial planets and the giant planets, and the outer Kuiper belt is sculpted by the giant planets.

“Our findings echo recent results showing multiple-planet systems are common beyond our sun,” said Kate Su, an astronomer at the Steward Observatory at the University of Arizona, Tucson. Su presented the results Tuesday at the American Astronomical Society meeting in Long Beach, Calif., and is lead author of a paper on the findings accepted for publication in the Astrophysical Journal.

via NASA, ESA Telescopes Find Evidence for Asteroid Belt Around Vega – NASA Jet Propulsion Laboratory.

Campaign for the Establishment of a United Nations Parliamentary Assembly (UNPA)

The Campaign for the Establishment of a United Nations Parliamentary Assembly (UNPA) is a global network of parliamentarians and non-governmental organizations advocating citizen’s representation at the United Nations.

At the Campaign’s launch in April 2007 at more than one dozen events on five continents an international “Appeal for the Establishment of a UN Parliamentary Assembly” was published. In April 2009 the Campaign issued a “Call for Global Democratic Oversight of International Financial and Economic Institutions”. The Campaign’s statements are supported by 4942 individuals from 152 countries, among them 834 members of parliament, and 349 NGOs from all around the world.

Four international conferences have taken place so far: In November 2007 in the Palais des Nations in Geneva under the patronage of former UN Secretary-General Boutros Boutros-Ghali, in November 2008 in the European Parliament, in October 2009 in New York and in October 2010 in the Senate of Argentina in Buenos Aires.

The Campaign’s Secretariat is led by the Committee for a Democratic United Nations. The work of the Campaign is guided by an informal Steering Committee, which helps to define the Campaign’s goals, policies and strategies.

The Campaign’s objectives

  • To make the UNPA proposal visible in political debates and the media
  • To facilitate the creation of national and local networks of individuals, non-governmental organizations and parliamentarians advocating a UNPA in their sphere of influence
  • To establish a global multi-stakeholder coalition which unites parliamentary and civil society efforts for a U.N. Parliamentary Assembly
  • To facilitate contacts and debates with potentially like-minded parliaments and governments

More information at unpacampaign.org

Earliest Bladelet Technology 70ky ago

A haul of stone blades from a cave in South Africa suggests that early humans were already masters of complex technology more than 70,000 years ago. The journal Nature reports on the new find which suggests that early humans passed on this knowledge down the generations. Dr. Curtis Marean, an archaeologist at Arizona State University in Tempe, who led the team that found the bladelets and Dr. Matthew Pope from the University College London argue that this could be the earliest evidence of truly modern human behaviour.

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The Observer says “Big History theories pose latest challenge to traditional curriculum”

A provocative new theory of history which has won influential support from Bill Gates poses the latest challenge to the coalition government plans to return to a traditional school curriculum.Big History, a movement spearheaded by the Oxford-educated maverick historian David Christian, is based on the idea that the academic study of the past can no longer be carried out from a nationalist perspective. Christian and his acolytes argue that the discipline will progress only once it charts human activity with a global scope, looking at chains of cause and effect that do not respect national borders. On a Big History course, the species Homo sapiens is not even mentioned until more than halfway through.

via Big History theories pose latest challenge to traditional curriculum | Education | The Observer.

Skilled hunters 300,000 years ago

Archeologists from the University of Tübingen have found eight extremely well-preserved spears — an astonishing 300,000 years old, making them the oldest known weapons anywhere. The spears and other artifacts as well as animal remains found at the site demonstrate that their users were highly skilled craftsmen and hunters, well adapted to their environment — with a capacity for abstract thought and complex planning comparable to our own. It is likely that they were members of the species Homo heidelbergensis, although no human remains have yet been found at the site.

via Skilled hunters 300,000 years ago.