Abstract:
:Chromatin organization within the nucleus is a vital regulator of genome function, yet its mechanical coupling to the nuclear architecture has remained elusive. To directly investigate this coupling, we locally modulated chromatin structure in living cells using nanoparticle-based laser perturbation. Unusual differences in the response of the cell nucleus were observed depending on the nuclear region that was perturbed--the heterochromatin, the euchromatin, and the nuclear envelope. This response varied under different conditions of cellular perturbations such as ATP depletion, apoptosis, and inhibition of histone deacetylases. Our studies implicate heterochromatin organization in imparting mechanical stability to the cell nucleus and suggest that nuclear size and shape are the result of interplay between nuclear and cytoplasmic anchors.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Mazumder A,Shivashankar GVdoi
10.1529/biophysj.106.102202subject
Has Abstractpub_date
2007-09-15 00:00:00pages
2209-16issue
6eissn
0006-3495issn
1542-0086pii
S0006-3495(07)71476-5journal_volume
93pub_type
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