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Single-crosslink microscopy in a biopolymer network dissects local elasticity from molecular fluctuations.

ABSTRACT: Polymer networks are fundamental from cellular biology to plastics technology but their intrinsic inhomogeneity is masked by the usual ensemble-averaged measurements. Here, we construct direct maps of crosslinks-symbolic depiction of spatially-distributed elements highlighting their physical features and the relationships between them-in an actin network. We selectively label crosslinks with fluorescent markers, track their thermal fluctuations, and characterize the local elasticity and cross-correlations between crosslinks. Such maps display massive heterogeneity, reveal abundant anticorrelations, and may contribute to address how local responses scale up to produce macroscopic elasticity. Single-crosslink microscopy offers a general, microscopic framework to better understand crosslinked molecular networks in undeformed or strained states.

SUBMITTER: Jiang L

PROVIDER: S-EPMC6658493 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature

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Single-crosslink microscopy in a biopolymer network dissects local elasticity from molecular fluctuations.

Jiang Lingxiang L Xie Qingqiao Q Tsang Boyce B Granick Steve S

Nature communications 20190725 1

Polymer networks are fundamental from cellular biology to plastics technology but their intrinsic inhomogeneity is masked by the usual ensemble-averaged measurements. Here, we construct direct maps of crosslinks-symbolic depiction of spatially-distributed elements highlighting their physical features and the relationships between them-in an actin network. We selectively label crosslinks with fluorescent markers, track their thermal fluctuations, and characterize the local elasticity and cross-co ...[more]

PMID: 31346168

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