PLoS Computational Biology (Jun 2020)

Circuits with broken fibration symmetries perform core logic computations in biological networks.

  • Ian Leifer,
  • Flaviano Morone,
  • Saulo D S Reis,
  • José S Andrade,
  • Mariano Sigman,
  • Hernán A Makse

DOI
https://doi.org/10.1371/journal.pcbi.1007776
Journal volume & issue
Vol. 16, no. 6
p. e1007776

Abstract

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We show that logic computational circuits in gene regulatory networks arise from a fibration symmetry breaking in the network structure. From this idea we implement a constructive procedure that reveals a hierarchy of genetic circuits, ubiquitous across species, that are surprising analogues to the emblematic circuits of solid-state electronics: starting from the transistor and progressing to ring oscillators, current-mirror circuits to toggle switches and flip-flops. These canonical variants serve fundamental operations of synchronization and clocks (in their symmetric states) and memory storage (in their broken symmetry states). These conclusions introduce a theoretically principled strategy to search for computational building blocks in biological networks, and present a systematic route to design synthetic biological circuits.