Out-of-equilibrium noise facilitates inference from protein sequence data

Dietler, N.; Malbranke, C.; Bitbol, A.-F.

doi:10.1101/2025.05.14.654088

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bioRxiv · 10.1101/2025.05.14.654088

Out-of-equilibrium noise facilitates inference from protein sequence data

Dietler, N.·Malbranke, C.·Bitbol, A.-F.

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Abstract

Homologous proteins have similar three-dimensional structures and biological functions that shape their sequences. The resulting coevolution-driven correlations underlie methods from Potts models to AlphaFold, which infer protein structure and function from sequences. Using a minimal model, we show that fluctuating selection strength and the onset of new selection pressures improve coevolutionbased inference of structural contacts. Our conclusions extend to realistic synthetic data and to the inference of interaction partners. Out-of-equilibrium noise arising from ubiquitous variations in natural selection thus enhances, rather than hinders, the success of inference from protein sequences.

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Dietler, N., Malbranke, C., Bitbol, A.-F.. 2025-05-17. Out-of-equilibrium noise facilitates inference from protein sequence data. https://doi.org/10.1101/2025.05.14.654088

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