Abstract:
:We study a Brownian dynamics simulation model of a biopolymeric shell deformed by axial forces exerted at opposing poles. The model exhibits two distinct, linear force-extension regimes, with the response to small tensions governed by linear elasticity and the response to large tensions governed by an effective spring constant that scales with radius as R-0.25. When extended beyond the initial linear elastic regime, the shell undergoes a hysteretic, temperature-dependent buckling transition. We experimentally observe this buckling transition by stretching and imaging the lamina of isolated cell nuclei. Furthermore, the interior contents of the shell can alter mechanical response and buckling, which we show by simulating a model for the nucleus that quantitatively agrees with our micromanipulation experiments stretching individual nuclei.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Banigan EJ,Stephens AD,Marko JFdoi
10.1016/j.bpj.2017.08.034subject
Has Abstractpub_date
2017-10-17 00:00:00pages
1654-1663issue
8eissn
0006-3495issn
1542-0086pii
S0006-3495(17)30929-3journal_volume
113pub_type
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