Self-Assembly of Informational Polymers by Templated Ligation

Minimal mechanism for cyclic templating of length-controlled copolymers under isothermal conditions

“…Indeed, in Ref. 40 , in a bottom-up, coarse-grained model of a replicating system that obeyed similar dynamics to that described by the model in Fig. 2, the authors observed the formation of only long polymers that remained bound in complexes under isothermal conditions.…”

“…One could imagine, if the concentration of polymers in the bath grew to significant levels, that rebinding could occur. Indeed, the rebinding and subsequent elongation of prod-ucts was presented as a plausible pathway to the generation of longer RNA oligomers, bridging a portion of the gap between short RNA building blocks and the long RNA molecules that make up ribozymes in a pair of papers on templated ligation in an RNA world 39,40 . However, in our mechanism, polymerisation is coupled to the disruption of the copy-template bonds, reducing the interaction strength that most units in the polymer chain could rebind by.…”

“…In a recent theoretical and experimental work on non-enzymatic templated assembly, Rosenberger et al demonstrated that polymer aggregates with well-defined length-scales can be generated from short building blocks under isothermal conditions. However, these polymers were bound up in complexes, not separated from their templates 40 .…”

“…This disparity suggests a poor understanding of templating relative to self-assembly, and also represents a missed opportunity to harness biology's most important mechanism of producing complexity -both to generate synthetic sequence-controlled polymers 30 , and in the context of combinatorial molecular discovery 31,32 . Moreover, central questions in the RNA world hypothesis, and the origin of life itself, relate to the appearance of the first systems that could reliably copy sequence information encoded in templates [33][34][35][36][37][38][39][40] . Therefore, in this paper, we investigate minimal mechanisms for templated copying through a series of computational models that will guide the design of synthetic template copying systems.…”

“…Braun and colleagues have exploited the convective currents generated by thermal gradients, inspired by oceanic thermal vents 58 , with templating and polymerisation occurring in cool regions and separation in hot regions [53][54][55] . Environments with spatially and/or temporally varying conditions are thought to have been essential in the emergence of pre-biotic RNA-zymes from short building blocks under the RNA world hypothesis of the emergence of life [33][34][35][36][37][38][39][40] .…”