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Origin of exponential growth in nonlinear reaction networks.

ABSTRACT: Exponentially growing systems are prevalent in nature, spanning all scales from biochemical reaction networks in single cells to food webs of ecosystems. How exponential growth emerges in nonlinear systems is mathematically unclear. Here, we describe a general theoretical framework that reveals underlying principles of long-term growth: scalability of flux functions and ergodicity of the rescaled systems. Our theory shows that nonlinear fluxes can generate not only balanced growth but also oscillatory or chaotic growth modalities, explaining nonequilibrium dynamics observed in cell cycles and ecosystems. Our mathematical framework is broadly useful in predicting long-term growth rates from natural and synthetic networks, analyzing the effects of system noise and perturbations, validating empirical and phenomenological laws on growth rate, and studying autocatalysis and network evolution.

SUBMITTER: Lin WH

PROVIDER: S-EPMC7668091 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature

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Origin of exponential growth in nonlinear reaction networks.

Lin Wei-Hsiang WH Kussell Edo E Young Lai-Sang LS Jacobs-Wagner Christine C Jacobs-Wagner Christine C

Proceedings of the National Academy of Sciences of the United States of America 20201022 45

Exponentially growing systems are prevalent in nature, spanning all scales from biochemical reaction networks in single cells to food webs of ecosystems. How exponential growth emerges in nonlinear systems is mathematically unclear. Here, we describe a general theoretical framework that reveals underlying principles of long-term growth: scalability of flux functions and ergodicity of the rescaled systems. Our theory shows that nonlinear fluxes can generate not only balanced growth but also oscil ...[more]

PMID: 33093194

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