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02/29/2008: "Life arose from inherent conditions of the universe"

Since the classic Miller-Urey experiments, science has steadily expanded the range of essential molecules that can be produced under conditions that might reasonably expected to have been present on the early earth.

With the components of nucleic acids in place, Ellington traced a path through the RNA world to a molecule that could self-replicate. Past attempts to jump to a complex, self-replicating RNA molecule seem to have been on the wrong track. Short palindromic RNA sequences can apparently help catalyze the formation of complementary sequences, meaning what's needed is actually an RNA that can link these short sequences into longer, more complex ones. A number of such sequences, termed RNA ligases, have been identified. Several labs have shown that these ligases can then be improved by an essentially Darwinian process of random mutation followed by selection for increased efficiency.

Ellington's final point was that we can still see remnants of the RNA world in aspects of biology that are common to all life. He noted that many of the cofactors used by modern proteins, including ATP itself, are derivatives of the chemical components of RNA.

[ The Universe is its own prime mover. Not a paradox when you think deeply on it. ]

http://arstechnica.com/articles/culture/state-of-the-art-evolution.ars