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+ - Two mutations triggered an evolutionary leap 500 million years ago->

Submitted by Taco Cowboy
Taco Cowboy (5327) writes ""Changes in just two letters of the genetic code in our deep evolutionary past caused a massive shift in the function of one protein and set in motion the evolution of our present-day hormonal and reproductive systems," said Joe Thornton, PhD, professor of human genetics and ecology & evolution at the University of Chicago

In a feat of "molecular time travel" the researchers resurrected and analyzed the functions of the ancestors of genes that play key roles in modern human reproduction, development, immunity and cancer. By re-creating the same DNA changes that occurred during those genes' ancient history, the team showed that two mutations set the stage for hormones like estrogen, testosterone and cortisol to take on their crucial present-day roles

"If those two mutations had not happened, our bodies today would have to use different mechanisms to regulate pregnancy, libido, the response to stress, kidney function, inflammation, and the development of male and female characteristics at puberty," Thornton said

Understanding how the genetic code of a protein determines its functions would allow biochemists to better design drugs and predict the effects of mutations on disease. Thornton said the discovery shows how evolutionary analysis of proteins' histories can advance this goal, Before the group's work, it was not previously known how the various steroid receptors in modern species distinguish estrogens from other hormones

They found that just two changes in the ancient receptor's gene sequence caused a 70,000-fold shift in preference away from estrogens toward other steroid hormones. The researchers also used biophysical techniques to identify the precise atomic-level mechanisms by which the mutations affected the protein's functions. Although only a few atoms in the protein were changed, this radically rewired the network of interactions between the receptor and the hormone, leading to a massive change in function

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+ - One-time pad from Caltech offers uncrackable cryptography->

Submitted by zrbyte
zrbyte (1666979) writes "One-time pads are the holy grail of cryptography — they are impossible to crack, even in principle. However, the ability to copy electronic code makes one-time pads vulnerable to hackers. Now engineers at the California Institute of Technology in Pasadena, have found a way round this to create a system of cryptography that is invulnerable to electronic attack. Their solution is based on a special kind of one-time pad that generates a random key through the complexity of its physical structure, namely shining a light through a diffusive glass plate."
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Comment: Re:This ain't the first time ... (Score 1) 470

by zrbyte (#42806205) Attached to: Is the Era of Groundbreaking Science Over?

You make a good point here. Usually a starting-point for totally new physics are unexplained measurement results like the Michelson - Morley interferometry measurements. With this in mind, there are some really big questions out there, like: what is dark matter/energy. The answer to which may be paradigmshifting stuff. On a less dramatic note, we still don't understand what makes high temperature superconductivity work. Understanding this phenomenon could lead to revolutions in "ordinary" condensed matter physics (not to mention a few Noble prizes).

Statistics are no substitute for judgement. -- Henry Clay

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