Non-enzymatic primer extension with strand displacement
- Howard Hughes Medical Institute, Massachusetts General Hospital, United States
- Harvard University, United States
Abstract
Non-enzymatic RNA self-replication is integral to the emergence of the 'RNA World'. Despite considerable progress in non-enzymatic template copying, demonstrating a full replication cycle remains challenging due to the difficulty of separating the strands of the product duplex. Here, we report a prebiotically plausible approach to strand displacement synthesis in which short 'invader' oligonucleotides unwind an RNA duplex through a toehold/branch migration mechanism, allowing non-enzymatic primer extension on a template that was previously occupied by its complementary strand. Kinetic studies of single-step reactions suggest that following invader binding, branch migration results in a 2:3 partition of the template between open and closed states. Finally, we demonstrate continued primer extension with strand displacement by employing activated 3′-aminonucleotides, a more reactive proxy for ribonucleotides. Our study suggests that complete cycles of non-enzymatic replication of the primordial genetic material may have been facilitated by short RNA oligonucleotides.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files.
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Author details
Funding
Simons Foundation (290363)
- Jack W Szostak
National Science Foundation (CHE-1607034)
- Jack W Szostak
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2019, Zhou et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Non-enzymatic primer extension with strand displacement
eLife 8:e51888.
https://doi.org/10.7554/eLife.51888
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