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To: siunevada

Thus there is a paradox. Both nucleic acids and proteins are required to function before selection can act at present, and yet the origin of this association is too improbable to have occurred without selection. (T. Dobzhansky et al, Evolution, 1977, 359)

I'm not saying this thought is so convincing that all discussion is closed. It's just a curious thing.

Keep going back on the evolutionary trail and you come to this point. How did such complex structures as nucleic acids and proteins come to be? One can't exist without the other. They are interdependent.

Thomas Cech earned the Nobel Prize in 1989 for discovering that this isn't always true. In fact there are over 300 examples of catalytic RNA that have been found in nature since then.

You might enjoy some of these (somewhat technical) video lectures by Cech. See especially RNA as an Enzyme: Discovery, Origins of Life, and Medical Possibilities [DSL version]

If you google on "Thomas Cech" or "ribozyme" you'll find a lot of articles on this.

303 posted on 08/03/2004 5:14:52 PM PDT by jennyp (Tremble and cower, Osama! John Edwards is comin' to getcha!)
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To: jennyp; Dimensio; stremba
Thomas Cech earned the Nobel Prize in 1989 for discovering that this isn't always true. In fact there are over 300 examples of catalytic RNA that have been found in nature since then.

Thanks for the reference.

I read his Nobel lecture. Completely over my head but I still read it. I caught some of his excitement about the discoveries they were making. And he injects a small touch of humor here and there, good lecture.

These were interesting comments toward the end:

Origin of Life Fantasies

The discoveries of RNA self-splicing and the enzymatic activity of RNase PRNA rekindled earlier speculation concerning the possible role of RNA in the origin of life (Woese, 1967; Crick, 1968; Orgel, 1968). Contemporary cells depend on a complex interplay of nucleic acids and proteins, the former serving as informational molecules and the latter as the catalysts that replicate and express the information. Certainly the first self-reproducing biochemical system also had an absolute need for both informational and catalytic molecules. The dilemma was therefore: Which came first, the nucleic acid or the protein, the information or the function? One solution would be the co-evolution of nucleic acids and proteins (Eigen, 1971). The finding that RNA can be a catalyst as well as an information-carrier lent plausibility to an alternative scenario: the first self-reproducing system could have consisted of RNA alone (Sharp, 1985; Pace & Marsh, 1985; Orgel, 1986).

392 posted on 08/04/2004 8:32:50 AM PDT by siunevada
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