Thursday, April 18, 2013

Chicken, Meet Eggosome

One of the most mysterious questions in science is that of how the whole intricate apparatus of life arose in the first place.  All Earthly life is very much the same at the fundamental level, the vast chemical factory of the cell.  Three critical elements are the mechanism of information storage (DNA), the apparatus for translating the directions written in the DNA into proteins (RNA & proteins), and the proteins that do all the chemical and mechanical work of the cell.  None can carry out their function without the other two.

Recent work has given us a clue, though.  RNA can't compete with proteins in general catalysis, but it does turn out to have some catalytic roles.  Most importantly, it turns out to be the RNA of the ribosome (rRNA) that does the all important task of catalyzing the formation of the peptide bond in the ribosome, the step that produces a protein out of amino acids.

This strongly hints that RNA got there first.