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[deleted] t1_jbotdcr wrote

Reply to comment by blauw67 in I just learned that the known shortest DNA in an “organism” is about 1700 base pairs in a certain virus. Is there a minimum amount of “code” required for an organism (or virus) to function in any capacity? by mcbergstedt

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Nemisis_the_2nd t1_jbowxzw wrote

Yup. Its theorised that that was how life originally came about too: self-replicating nucleotide structures. All the other stuff came afterwards as imperfect copying resulted in changes (and increasing complexity) over time.

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Swaayze t1_jbp0zmy wrote

Do you happen to have a link to one of these papers? Sounds interesting

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Nemisis_the_2nd t1_jbp1w1j wrote

There's not really any single paper about it, so much as it being one of the most commonly held beliefs among biologists looking at how life might originate.

There are a lot of variations to the idea too though: some might argue that DNA came first, while others suggest that life actually started with proteins, and DNA/RNA came later. So far as I understand, the protein theory is most widely supported, and is partly why scientists get excited when they find amino acids somewhere.

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LePlant01 t1_jbpi7sz wrote

Isn't this basically the "RNA world" hypothesis? There should definitely be papers on that. Recently there was a new paper on the question how it could actually have been possible for the RNA bases to emerge from inorganic molecules. For a long time the RNA world hypothesis was (is) very popular yet from a chemistry point of view it is quite hard for RNA bases to form from inorganic starting materials (if I understood correctly). Whereas amino acids form comparatively easy from such starting materials. That's why some hypothesized that proteins might have been the origin of life. Yet protein can't replicate themselves. Even prions need existing correctly folded proteins to convert them into their prion state. That's the cool thing about ribozymes. They can self replicate.

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LePlant01 t1_jbph68t wrote

There is a book by Freeman Dyson called "Origins of life". He talks about the possibility of a self replicating polynucleotide as the supposed origin of life on earth.

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LePlant01 t1_jbpgueh wrote

But if these would really be the "origin of life" why are they only found in plants?

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Ficrab t1_jbqdciz wrote

You have a version of these within your genome as well. Look up retrotransposons and other genetic mobile elements.

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