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Directional memory and caged dynamics in cytoskeletal remodelling.

ABSTRACT: We report directional memory of spontaneous nanoscale displacements of an individual bead firmly anchored to the cytoskeleton of a living cell. A novel method of analysis shows that for shorter time intervals cytoskeletal displacements are antipersistent and thus provides direct evidence in a living cell of molecular trapping and caged dynamics. At longer time intervals displacements are persistent. The transition from antipersistence to persistence is indicative of a time-scale for cage rearrangements and is found to depend upon energy release due to ATP hydrolysis and proximity to a glass transition. Anomalous diffusion is known to imply memory, but we show here that memory is attributed to direction rather than step size. As such, these data are the first to provide a molecular-scale physical picture describing the cytoskeletal remodelling process and its rate of progression.

SUBMITTER: Lenormand G

PROVIDER: S-EPMC2394503 | biostudies-literature | 2007 Sep

REPOSITORIES: biostudies-literature

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Directional memory and caged dynamics in cytoskeletal remodelling.

Lenormand Guillaume G Chopin Julien J Bursac Predrag P Fredberg Jeffrey J JJ Butler James P JP

Biochemical and biophysical research communications 20070705 4

We report directional memory of spontaneous nanoscale displacements of an individual bead firmly anchored to the cytoskeleton of a living cell. A novel method of analysis shows that for shorter time intervals cytoskeletal displacements are antipersistent and thus provides direct evidence in a living cell of molecular trapping and caged dynamics. At longer time intervals displacements are persistent. The transition from antipersistence to persistence is indicative of a time-scale for cage rearran ...[more]

PMID: 17631276

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