Talmudic Question #55

The Central Dogma of Molecular Biology has never been seriously challenged. Here is your chance: can you conceive of a mechanism whereby genetic information can flow directly from proteins to nucleic acids?

Comments

[Mark O. Martin]

This description of "non-Dogmatic" information transfer reminds me of all the great debates between Crick and Gamov and the others about how coding would work. But I do wonder if we are missing things. The Cairns-Smith "life from clay" was one approach:

http://en.wikipedia.org/wiki/Graham_Cairns-Smith

And so far as the deeply weird, how about "cortical inheritance"? First described in protists, it is far more widespread:

http://science.jrank.org/pages/48371/Cortical-Inheritance.html

Who knows what we are all missing? Joshua Lederberg used to wonder if we are so fixated on DNA/RNA based life that we might miss "shadow life" here on Earth! He used to suggest trying to grow organisms from an inoculum to which was added a huge amount of radioactive phosphorus. I don't know if anyone ever tried that!

[Nathan Myers]

Nature knows no dogma.

The simplest case would be a protein that excises a whole gene. If that's too crude, I find it easy enough to believe in a protein that recognizes a particular sequence, and substitutes one base for another in a specified position, e.g. turning FOXP2 from simian to human form.

Details, please, on the prize?

Elio's reply. Plane ticket to Stockholm is in the mail

[Manuel Sánchez]

A kind of chimera between a chaperone, a ribosome and a RNA-polymerase. The chaperon domain will unfold the protein so the side chains of the amino acids could be recognised and read by the ribosome domain. In this part, each side chain will be asociated with a set of specific three bases. For example, leucine with its long hydrocarbon chain will always be asociated with a cytosine, uracil and cytosine. There is not need for a degenerate code this time because we go from 20 to 64 amino acids. This is the tricky part, because it is difficult to imagine an active center that has the side chain and allows the entrance and location of nucleotides. After that, the polymerization of nucleic acid occurs (I bet for RNA) thanks to the polymerase domain.

Because it is an inversion of the proccess I propose the name of chaperoborimerase for this chimeric macromolecule

By the way. Congratulations for the recent prize.