Related Experiment Video
Updated: May 26, 2026

Spatiotemporal Control of Protein Activity through Optogenetic Allosteric Regulation
Published on: October 4, 2024
Nonequilibrium phase transitions in biomolecular signal transduction
Eric Smith1, Supriya Krishnamurthy, Walter Fontana
1Santa Fe Institute, Santa Fe, New Mexico 87501, USA.
Abstract:
We study a mechanism for reliable switching in biomolecular signal-transduction cascades. Steady bistable states are created by system-size cooperative effects in populations of proteins, in spite of the fact that the phosphorylation-state transitions of any molecule, by means of which the switch is implemented, are highly stochastic. The emergence of switching is a nonequilibrium phase transition in an energetically driven, dissipative system described by a master equation. We use operator and functional integral methods from reaction-diffusion theory to solve for the phase structure, noise spectrum, and escape trajectories and first-passage times of a class of minimal models of switches, showing how all critical properties for switch behavior can be computed within a unified framework.
Related Concept Videos
Amplifying Signals via Enzymatic Cascade
Phase Transitions: Melting and Freezing
Diversity in Cell Signaling Responses
Graded and Abrupt Responses
Some signaling systems generate...
Intracellular Signaling Cascades
Intracellular Signaling Cascades
Amplifying Signals via Second Messengers
