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Updated: May 29, 2026
06:23
Detection of Nuclear Blebbing and DNA Leakage in Mammalian Cells by Immunofluorescence
Published on: January 17, 2025
Nuclear envelope defects impede a proper response to micronuclear DNA lesions
Mariona Terradas1, Marta Martín, Laia Hernández
1Department of Cell Biology, Physiology and Immunology, Universitat Autònoma de Barcelona, Bellaterra, Spain.
Mutation Research
|September 28, 2011
Summary
Micronuclei DNA lesions poorly activate cellular repair systems. The micronuclear envelope hinders access of DNA repair factors, preventing effective damage response to UV photoproducts.
Area of Science:
- Cellular Biology
- Molecular Biology
- Genetics
Background:
- The DNA damage response (DDR) machinery protects nuclear DNA from damage.
- The DDR's efficacy in micronuclei, which contain damaged DNA, remains unclear.
Purpose of the Study:
- To investigate if DNA within micronuclei is protected by the cellular DDR.
- To determine the recruitment of excision repair factors to micronuclear DNA photolesions.
Main Methods:
- Primary human dermal fibroblasts were exposed to UV-C light to induce DNA photolesions.
- Immunofluorescence techniques were used to visualize the recruitment of Nucleotide Excision Repair (NER) factors.
Main Results:
- Most micronuclei lacked NER factors, indicating a deficient DNA damage response.
- Micronuclear envelope integrity was identified as a key factor influencing DNA repair within micronuclei.
Conclusions:
- UV photoproducts in micronuclei generally fail to elicit an effective DNA damage response.
- Repair factors cannot access micronuclear chromatin, leading to poor processing of photolesions in radiation-induced micronuclei.
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