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bioRxiv · 10.1101/123554

Single-Cell Statistical Thermodynamics In Early Embryo Development

Giuliani, A.·Tsuchiya, M.·Yoshikawa, K.
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Abstract

A statistical thermodynamics approach to the temporal development of biological regulation provides a phenomenological description of the dynamical behavior of genome expression in terms of autonomous self-organization with a critical transition (Self-Organized Criticality: SOC). In early mouse embryo development, the dynamical change in the self-organization of overall expression determines how and when reprogramming of the genome-expression state occurs. Reprogramming occurs via a transition state (climbing over an epigenetic landscape), where the critical-regulation pattern of the zygote state disappears. A critical transition is well captured in terms of the bimodality of expression ensembles, which reflects distinct thermodynamic states (critical states). These critical states exhibit a genome avalanche pattern: competition between order (scaling) and disorder (divergence) around a critical point. The genome avalanche in mouse embryo development, which is committed to erase a previous ordered state, reveals that the direction of early embryo single-cell development traverses the same steps as in differentiation, but in the opposite order of self-organization.

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Giuliani, A., Tsuchiya, M., Yoshikawa, K.. 2017-04-03. Single-Cell Statistical Thermodynamics In Early Embryo Development. https://doi.org/10.1101/123554

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