Abstract:
:Keratin intermediate filaments form dynamic intracellular networks, which span the entire cytoplasm and provide mechanical strength to the cell. The mechanical resilience of the keratin intermediate filament network itself is determined by filament bundling. The bundling process can be reproduced in artificial conditions in the absence of any specific cross-linking proteins, which suggests that it is driven by generic physical forces acting between filaments. Here, we suggest a detailed model for bundling of keratin intermediate filaments based on interfilament electrostatic and hydrophobic interactions. It predicts that the process is limited by an optimal bundle thickness, which is determined by the electric charge of the filaments, the number of hydrophobic residues in the constituent keratin polypeptides, and the extent to which the electrolyte ions are excluded from the bundle interior. We evaluate the kinetics of the bundling process by considering the energy barrier a filament has to overcome for joining a bundle.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Haimov E,Windoffer R,Leube RE,Urbakh M,Kozlov MMdoi
10.1016/j.bpj.2020.05.024subject
Has Abstractpub_date
2020-07-07 00:00:00pages
65-74issue
1eissn
0006-3495issn
1542-0086pii
S0006-3495(20)30443-4journal_volume
119pub_type
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