2018/07/09 by Konstantin Speckner, Lorenz Stadler, Matthias Weiß · 1 citation
Biochemistry, Genetics and Molecular Biology · Physics and Astronomy · Engineering · #Lipid Membrane Structure and Behavior #stochastic dynamics and bifurcation #Microfluidic and Bio-sensing Technologies
paper · doi:10.1103/physreve.98.012406
openalex publication_date 2018/07/09 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01
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 \ensuremath⟨r2(\ensuremathτ)\ensuremath⟩t\ensuremath∼\ensuremathτ^\ensuremathα with \ensuremathα\ensuremath≈0.5 in untreated cells and \ensuremathα\ensuremath≈0.3 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 df\ensuremath≈1.6 on mesoscopic scales and we provide evidence that the organelle's dynamics is governed by fractons.