RT Journal Article
SR Electronic
T1 Subtle changes in crosslinking drive diverse anomalous transport characteristics in actin-microtubule networks
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2020.12.01.405142
DO 10.1101/2020.12.01.405142
A1 S. J. Anderson
A1 J. Garamella
A1 S. Adalbert
A1 R. J. McGorty
A1 R. M. Robertson-Anderson
YR 2020
UL http://biorxiv.org/content/early/2020/12/02/2020.12.01.405142.abstract
AB Anomalous diffusion in crowded and complex environments is widely studied due to its importance in intracellular transport, fluid rheology and materials engineering. Specifically, diffusion through the cytoskeleton, a network comprised of semiflexible actin filaments and rigid microtubules that interact both sterically and via crosslinking, plays a principal role in viral infection, vesicle transport and targeted drug delivery. Here, we elucidate the impact of crosslinking on particle diffusion in composites of actin and microtubules with actin-actin, microtubule-microtubule and actin-microtubule crosslinking. We analyze a suite of complementary transport metrics by coupling single-particle tracking and differential dynamic microscopy. Using these orthogonal techniques, we find that particles display non-Gaussian and non-ergodic subdiffusion that is markedly enhanced by cytoskeletal crosslinking of any type, which we attribute to suppressed microtubule mobility. However, the extent to which transport deviates from normal Brownian diffusion depends strongly on the crosslinking motif – with actin-microtubule crosslinking inducing the most pronounced anomalous characteristics – due to increased actin fluctuation heterogeneity. Our results reveal that subtle changes to actin-microtubule interactions can have dramatic impacts on diffusion in the cytoskeleton, and suggest that less mobile and more locally heterogeneous networks lead to more strongly anomalous transport.Competing Interest StatementThe authors have declared no competing interest.