ScienceDaily: Top Environment News

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• Elusive Z- DNA found on nucleosomes
• Italian shipwreck threatens to create second disaster at sea
• Gene critical to sense of smell in fruit fly identified
• Biodiversity crisis is worse than climate change, experts say
• Low temperatures enhance ozone degradation above the Arctic
• Speed limit for birds: Researchers find critical speed above which birds- and drones- are sure to crash

Elusive Z- DNA found on nucleosomes Posted: 20 Jan 2012 03:30 PM PST New research shows that left-handed Z-DNA, normally only found at sites where DNA is being copied, can also form on nucleosomes. The structure of DNA which provides the blueprint for life has famously been described as a double helix. To save space inside the nucleus, DNA is tightly wound around proteins to form nucleosomes which are then further wound and compacted into chromatin, which is further compacted into chromosomes. But this familiar image of a right handed coil (also called B-DNA) is not the only form of DNA. At sites where DNA is being copied into RNA (the messenger which is used as the instruction to make proteins) the DNA needs to unwind, and, in a process of negative supercoiling, can form a left-handed variety of the DNA double helix (Z-DNA).

Italian shipwreck threatens to create second disaster at sea Posted: 20 Jan 2012 03:27 PM PST An expert on the protection of threatened marine ecosystems has commented on the potential for ecological disaster posed by the 2,300 tons of fuel oil still aboard the capsized cruise ship Costa Concordia.

Gene critical to sense of smell in fruit fly identified Posted: 19 Jan 2012 10:04 PM PST Researchers have discovered that a gene called distal-less is critical to the fly's ability to receive, process and respond to smells.

Biodiversity crisis is worse than climate change, experts say Posted: 19 Jan 2012 10:03 PM PST Biodiversity is declining rapidly throughout the world. The challenges of conserving the world's species are perhaps even larger than mitigating the negative effects of global climate change, experts say.

Low temperatures enhance ozone degradation above the Arctic Posted: 19 Jan 2012 10:37 AM PST Extraordinarily cold temperatures in the winter of 2010/2011 caused the most massive destruction of the ozone layer above the Arctic so far: The mechanisms leading to the first ozone hole above the North Pole have now been investigated.

Speed limit for birds: Researchers find critical speed above which birds- and drones- are sure to crash Posted: 19 Jan 2012 10:37 AM PST Researchers find critical speed above which birds -- and drones -- are sure to crash.

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