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Water bear genes can shield our cells
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Water bear genes can shield our cells environmental stress, somehow making DNA inaccessible to any damaging agents,” says Takekazu Kunieda at the University of Tokyo. “This is the first identification of a DNAassociating protein that confers
THEY are the toughest animals on the planet, as far as we know. And now the secret behind one of their survival superpowers – resistance to radiation – is out. Tardigrades, also known as water bears, are tiny creatures that live in small bodies of water in habitats such as moss. They can also survive in the vacuum of outer space, withstand temperatures from close to absolute zero to nearly 100 °C and cope with pressures six times higher than those at the bottom of the deepest ocean. Now we know how they manage to endure radiation that would kill most other life on Earth. It is largely because they have evolved a bizarre protein that somehow shields their DNA. Short for “Damage suppressor”, Dsup appears to cuddle up to DNA and cocoon it from harm, but without disrupting its normal functions. It may also mop up DNAharming chemicals called reactive oxygen species. “We guess that Dsup binds densely to DNA to provide a shield against
Quantum teleportation record smashed THERE’S a new world record for quantum teleportation. Two independent teams have transferred quantum information over several kilometres of fibre optic networks. Establishing teleportation over long distances is a crucial step towards exchanging the quantum cryptographic keys needed for making data sent over such a network secure. The phenomenon involves the 10 | NewScientist | 24 September 2016
Meckes + Ottawa/SPL
Andy Coghlan
quantum states of one particle being transferred to another, distant particle without anything physical travelling between them. It relies on a property called entanglement, in which measuring the state of one particle immediately affects the state of its entangled partner. One way of doing this involves three participants: say, Alice, Bob and Charlie. First, Alice sends a particle (A) to Charlie. Bob, meanwhile, creates a pair of entangled particles (B & C), sends B to Charlie and holds on to C. Charlie receives both A and B, and measures the particles in such a way that it’s impossible to tell which
DNA protection and improved tolerance to radioactivity in animal cells.” Kunieda’s team discovered Dsup after fully sequencing the genome of Ramazzottius varieornatus, one of the most stress-tolerant tardigrade species. The protein also protected human kidney cells against radiation damage when they were genetically engineered to make Dsup themselves (Nature Communications, doi.org/bqtz).
“The human cells that made Dsup saw a reduction of around 40 to 50 per cent in the DNA damage caused by X-rays compared with control cells,” says Kunieda. He says that transferring the gene that makes Dsup into animals by genetic engineering might increase their resistance to radiation, although this would be trickier to do in a whole animal. “It could be helpful for space flight, radiotherapy and radiation workers in the far future,” says Kunieda. “It would be really wonderful, though this is getting near science fiction.” And the survival of an animal that produces Dsup could not be guaranteed under high radiation conditions as some vital cells and organs might still be lost despite the improved DNA protection for cells in general, he adds. Kunieda also found that water bears have extra copies of other protective genes. A now-disputed 2015 study suggested that tardigrades got many such genes from other organisms. Kunieda’s team found that, while some protective genes were imported, most were the tardigrade’s own. “It lays to rest the proposal that tardigrades acquired their extreme survival biology through massive acquisition of genes from other species,” says Mark Blaxter at the –So tough you’ll want my genes– University of Edinburgh, UK. n
particle was sent by Alice and which by Bob. This measurement transfers the quantum state of particle A to particle C, which is with Bob. Until recently, the record for teleportation across a cable was 800 metres. Now, Wolfgang Tittel at the University of Calgary in Canada and colleagues have teleported quantum states over 6.2 kilometres using part of Calgary’s fibre optic network (Nature Photonics, doi.org/bqr9). In
“In theory, this can make a quantum communication network that stretches between cities”
theory, this strategy can be extended to communicate between cities. Jian-Wei Pan at the University of Science and Technology of China and colleagues achieved a comparable separation using the city of Hefei’s fibre optic network, using a slightly different setup (Nature Photonics, doi.org/bqsb). “The two experiments can be seen as milestones on the path to a long-term goal, namely to build a fibre-based quantum internet connecting large cities,” says Johannes Kofler at the Max Planck Institute of Quantum Optics in Munich. Anil Ananthaswamy n
Water bear genes can shield our cells environmental stress, somehow making DNA inaccessible to any damaging agents,” says Takekazu Kunieda at the University of Tokyo. “This is the first identification of a DNAassociating protein that confers
THEY are the toughest animals on the planet, as far as we know. And now the secret behind one of their survival superpowers – resistance to radiation – is out. Tardigrades, also known as water bears, are tiny creatures that live in small bodies of water in habitats such as moss. They can also survive in the vacuum of outer space, withstand temperatures from close to absolute zero to nearly 100 °C and cope with pressures six times higher than those at the bottom of the deepest ocean. Now we know how they manage to endure radiation that would kill most other life on Earth. It is largely because they have evolved a bizarre protein that somehow shields their DNA. Short for “Damage suppressor”, Dsup appears to cuddle up to DNA and cocoon it from harm, but without disrupting its normal functions. It may also mop up DNAharming chemicals called reactive oxygen species. “We guess that Dsup binds densely to DNA to provide a shield against
Quantum teleportation record smashed THERE’S a new world record for quantum teleportation. Two independent teams have transferred quantum information over several kilometres of fibre optic networks. Establishing teleportation over long distances is a crucial step towards exchanging the quantum cryptographic keys needed for making data sent over such a network secure. The phenomenon involves the 10 | NewScientist | 24 September 2016
Meckes + Ottawa/SPL
Andy Coghlan
quantum states of one particle being transferred to another, distant particle without anything physical travelling between them. It relies on a property called entanglement, in which measuring the state of one particle immediately affects the state of its entangled partner. One way of doing this involves three participants: say, Alice, Bob and Charlie. First, Alice sends a particle (A) to Charlie. Bob, meanwhile, creates a pair of entangled particles (B & C), sends B to Charlie and holds on to C. Charlie receives both A and B, and measures the particles in such a way that it’s impossible to tell which
DNA protection and improved tolerance to radioactivity in animal cells.” Kunieda’s team discovered Dsup after fully sequencing the genome of Ramazzottius varieornatus, one of the most stress-tolerant tardigrade species. The protein also protected human kidney cells against radiation damage when they were genetically engineered to make Dsup themselves (Nature Communications, doi.org/bqtz).
“The human cells that made Dsup saw a reduction of around 40 to 50 per cent in the DNA damage caused by X-rays compared with control cells,” says Kunieda. He says that transferring the gene that makes Dsup into animals by genetic engineering might increase their resistance to radiation, although this would be trickier to do in a whole animal. “It could be helpful for space flight, radiotherapy and radiation workers in the far future,” says Kunieda. “It would be really wonderful, though this is getting near science fiction.” And the survival of an animal that produces Dsup could not be guaranteed under high radiation conditions as some vital cells and organs might still be lost despite the improved DNA protection for cells in general, he adds. Kunieda also found that water bears have extra copies of other protective genes. A now-disputed 2015 study suggested that tardigrades got many such genes from other organisms. Kunieda’s team found that, while some protective genes were imported, most were the tardigrade’s own. “It lays to rest the proposal that tardigrades acquired their extreme survival biology through massive acquisition of genes from other species,” says Mark Blaxter at the –So tough you’ll want my genes– University of Edinburgh, UK. n
particle was sent by Alice and which by Bob. This measurement transfers the quantum state of particle A to particle C, which is with Bob. Until recently, the record for teleportation across a cable was 800 metres. Now, Wolfgang Tittel at the University of Calgary in Canada and colleagues have teleported quantum states over 6.2 kilometres using part of Calgary’s fibre optic network (Nature Photonics, doi.org/bqr9). In
“In theory, this can make a quantum communication network that stretches between cities”
theory, this strategy can be extended to communicate between cities. Jian-Wei Pan at the University of Science and Technology of China and colleagues achieved a comparable separation using the city of Hefei’s fibre optic network, using a slightly different setup (Nature Photonics, doi.org/bqsb). “The two experiments can be seen as milestones on the path to a long-term goal, namely to build a fibre-based quantum internet connecting large cities,” says Johannes Kofler at the Max Planck Institute of Quantum Optics in Munich. Anil Ananthaswamy n