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Updated: Jun 11, 2026
06:23
Detection of Nuclear Blebbing and DNA Leakage in Mammalian Cells by Immunofluorescence
Published on: January 17, 2025
Lamin A precursor induces barrier-to-autointegration factor nuclear localization
Cristina Capanni1, Vittoria Cenni, Tokuko Haraguchi
1IGM-CNR, Unit of Bologna c/o IOR, Bologna, Italy. ccapanni@area.bo.cnr.it
Cell Cycle (Georgetown, Tex.)
|June 29, 2010
Summary
Accumulation of prelamin A, a protein precursor, causes aberrant nuclear structure. This study reveals that barrier-to-autointegration factor (BAF) translocates to the nucleus in response to prelamin A buildup, suggesting BAF mediates chromatin changes.
Area of Science:
- Cell Biology
- Molecular Biology
- Genetics
Background:
- Lamin A is a nuclear lamina protein synthesized as prelamin A.
- Defective prelamin A processing leads to nuclear accumulation and aberrant chromatin structure in laminopathies.
- Barrier-to-autointegration factor (BAF) is a DNA-binding protein involved in chromatin structure and gene regulation.
Purpose of the Study:
- To investigate the role of nuclear lamina components, specifically BAF, in prelamin A-induced chromatin remodeling.
- To determine if BAF localization is altered in cells accumulating prelamin A precursors.
- To explore the potential of BAF mediating prelamin A's chromatin effects.
Main Methods:
- Investigated BAF localization and expression in HEK293 cells and human fibroblasts with accumulating prelamin A.
- Utilized prelamin A interfering drugs for cell treatment.
- Performed coimmunoprecipitation to assess in vivo interactions between prelamin A/progerin and BAF.
Main Results:
- Prelamin A accumulation, including non-farnesylated and farnesylated forms, induced BAF nuclear translocation.
- Treatment with prelamin A interfering drugs mimicked these BAF translocation effects in human fibroblasts.
- Progerin accumulation in Hutchinson-Gilford progeria syndrome cells recruited BAF to the nucleus.
- Coimmunoprecipitation confirmed in vivo interactions between prelamin A/progerin and BAF.
Conclusions:
- Prelamin A accumulation alters BAF localization, promoting its nuclear translocation.
- BAF may act as a mediator for the chromatin remodeling effects induced by prelamin A.
- These findings provide insights into the molecular mechanisms underlying laminopathies.
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