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arXiv · 1008.0737

Protein-DNA computation by stochastic assembly cascade

Roy Bar-Ziv·Tsvi Tlusty·Albert Libchaber
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Abstract

The assembly of RecA on single-stranded DNA is measured and interpreted as a stochastic finite-state machine that is able to discriminate fine differences between sequences, a basic computational operation. RecA filaments efficiently scan DNA sequence through a cascade of random nucleation and disassembly events that is mechanistically similar to the dynamic instability of microtubules. This iterative cascade is a multistage kinetic proofreading process that amplifies minute differences, even a single base change. Our measurements suggest that this stochastic Turing-like machine can compute certain integral transforms.

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Roy Bar-Ziv, Tsvi Tlusty, Albert Libchaber. 2010-08-04. Protein-DNA computation by stochastic assembly cascade. https://doi.org/10.1073/pnas.162369099

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