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  • Letter
  • Open Access

Mesoscopic viscous-to-elastic transition as a signature of aging of biomolecular condensates

Minghao Li1 and Jie Lin1,2,*

  • *Contact author: linjie@pku.edu.cn
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Phys. Rev. Research 8, L042002 – Published 13 October, 2026

DOI: https://doi.org/10.1103/6kv2-kbnx

Abstract

Aging of biomolecular condensates, which progressively leads to solidlike states, is closely linked to biological functions and diseases. However, a unified physical picture that captures the aging dynamics remains elusive. Here, we introduce a viscoelastic model in which a condensate is a composite of viscous and elastic elements with coexisting serial and parallel connections. The model naturally yields a complex modulus with two relaxation times, unifying the Maxwell and Jeffreys models as special limits. When applied to aging PGL-3 condensates, our model reveals that an important driving force of aging is the conversion of viscous elements into elastic ones. In contrast, the mesoscopic structure topology of the condensates remains approximately invariant. Our stochastic aging model predicts that the condensate viscosity increases either exponentially or as a power-law function of the waiting time, in agreement with experiments.

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Phys. Rev. Research 8, L042002– Published 13 October, 2026
  • Received 24 November 2025
  • Accepted 17 September 2026
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

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