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Title: Anomalous and heterogeneous DNA transport in biomimetic cytoskeleton networks
The cytoskeleton, a complex network of protein filaments and crosslinking proteins, dictates diverse cellular processes ranging from division to cargo transport. Yet, the role the cytoskeleton plays in the intracellular transport of DNA and other macromolecules remains poorly understood. Here, using single-molecule conformational tracking, we measure the transport and conformational dynamics of linear and relaxed circular (ring) DNA in composite networks of actin and microtubules with variable types of crosslinking. While both linear and ring DNA undergo anomalous, non-Gaussian, and non-ergodic subdiffusion, the detailed dynamics are controlled by both DNA topology (linear vs. ring) and crosslinking motif. Ring DNA swells, exhibiting heterogeneous subdiffusion controlled via threading by cytoskeleton filaments, while linear DNA compacts, exhibiting transport via caging and hopping. Importantly, while the crosslinking motif has little effect on ring DNA, linear DNA in networks with actin–microtubule crosslinking is significantly less ergodic and shows more heterogeneous transport than with actin–actin or microtubule–microtubule crosslinking.  more » « less
Award ID(s):
1603925
PAR ID:
10184667
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Soft Matter
Volume:
16
Issue:
27
ISSN:
1744-683X
Page Range / eLocation ID:
6344 to 6353
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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