Related Experiment Video
Updated: May 30, 2025
06:23
Detection of Nuclear Blebbing and DNA Leakage in Mammalian Cells by Immunofluorescence
Published on: January 17, 2025
666
Nuclear blebs are associated with destabilized chromatin-packing domains
Emily M Pujadas Liwag1,2,3, Nicolas Acosta1,3, Luay Matthew Almassalha1,3,4
1Department of Biomedical Engineering, Northwestern University, Evanston, IL 60208, USA.
Journal of Cell Science
|January 29, 2025
Summary
Nuclear blebs, associated with diseases like cancer, show fragmented higher-order chromatin structures. This chromatin disruption within nuclear blebs may contribute to their formation and associated pathologies.
Area of Science:
- Cell Biology
- Genetics
- Biophysics
Background:
- Disrupted nuclear shape is linked to aging, cancer, and DNA damage.
- Nuclear blebs (herniations of the nuclear envelope) can arise from various cellular stresses and processes.
- Chromatin transformation is observed in bleb formation, but higher-order structural changes remain unclear.
Purpose of the Study:
- To investigate alterations in higher-order chromatin packing domain organization within nuclear blebs.
- To determine if changes in packing domain structure contribute to nuclear bleb formation.
Main Methods:
- Dual-partial wave spectroscopic microscopy to analyze chromatin packing domains.
- Single-molecule localization microscopy to examine constitutive heterochromatin structure.
- Induction of nuclear blebs via B-type lamin depletion and heterochromatin enzyme inhibition.
Main Results:
- Chromatin packing domains within nuclear blebs exhibit altered organization compared to the nuclear body.
- B-type lamin depletion and heterochromatin enzyme inhibition induce these chromatin transformations.
- Nanoscopic heterochromatin domains show fragmentation within bleb domains.
Conclusions:
- Nuclear blebs are characterized by a fragmented higher-order chromatin structure.
- Alterations in chromatin packing domains are associated with nuclear bleb formation.
- Findings provide insights into the biophysical mechanisms underlying nuclear bleb pathology.
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