Ligation of random oligomers leads to emergence of autocatalytic sequence network

Published: Aug. 18, 2020, 4:01 p.m.

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.08.18.253963v1?rss=1 Authors: Kudella, P. W., Tkachenko, A. V., Maslov, S., Braun, D. Abstract: The emergence of longer information-carrying and functional nucleotide polymers from random short strands was a major stepping stone at the dawn of life. But the formation of those polymers under temperature oscillation required some form of selection. A plausible mechanism is template-based ligation where theoretical work already suggested a reduction in information entropy. Here, we show how nontrivial sequence patterns emerge in a system of random 12mer DNA sequences subject to enzyme-based templated ligation reaction and temperature cycling. The strands acted both as a template and substrates of the reaction and thereby formed longer oligomers. The selection for templating sequences leads to the development of a multiscale ligation landscape. A position-dependent sequence pattern emerged with a segregation into mutually complementary pools of A-rich and T-rich sequences. Even without selection for function, the base pairing of DNA with ligation showed a dynamics resembling Darwinian evolution. Copy rights belong to original authors. Visit the link for more info