Enhanced diffusion in active intracellular transport.

A Caspi; R Granek; M Elbaum

doi:10.1103/physrevlett.85.5655

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Enhanced diffusion in active intracellular transport.

A Caspi·R Granek·M Elbaum

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Abstract

We show that within a living eukaryotic cell, mean square displacement of an engulfed microsphere shows enhanced diffusion scaling as t(3/2) at short times, with a clear crossover to subdiffusive or ordinary diffusion scaling at longer times. The motion, observed nearby the nucleus, is due to interactions with microtubule-associated motor proteins rather than thermal Brownian motion. We propose that time-dependent friction introduced by the intracellular polymer networks leads to sub-ballistic motion, analogous to subdiffusion observed in passive networks of semiflexible biopolymers.

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Algorithms Biological Transport, Active Cells, Cultured Diffusion Fibroblasts Fluorescent Antibody Technique Microspheres Molecular Motor Proteins Polystyrenes Rheology Journal Article Research Support, Non-U.S. Gov't

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A Caspi, R Granek, M Elbaum. 2000-12-25. Enhanced diffusion in active intracellular transport.. https://doi.org/10.1103/physrevlett.85.5655

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