Abstract
Large portions of the endoplasmic reticulum (ER) in eukaryotic cells are organized as dynamic networks whose segments are connected by three-way junctions. Here we show that ER junctions move subdiffusively with signatures of fractional Brownian motion and a strong dependence on the cytoskeleton's integrity: The time-averaged mean square displacement scales as with in untreated cells and when disrupting microtubules, with successive steps being anticorrelated in both cases. We explain our observations by considering ER junctions to move like monomers in (semi)flexible polymer segments immersed in a viscoelastic environment. We also report that ER networks have a nontrivial fractal dimension on mesoscopic scales and we provide evidence that the organelle's dynamics is governed by fractons.
- Received 22 March 2018
- Revised 4 June 2018
DOI:https://doi.org/10.1103/PhysRevE.98.012406
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