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Bloom Syndrome Helicase Compresses Single-Stranded DNA into Phase-Separated Condensates
Teng Wang1, Jiaojiao Hu2, Yanan Li1
1School of Life Science and Technology, ShanghaiTech University, Shanghai, 201210, China.
Angewandte Chemie (International Ed. in English)
|August 3, 2022
Summary
Bloom syndrome protein (BLM) can phase separate with single-stranded DNA (ssDNA), condensing it with ATP. This DNA helicase dismantles protective proteins, revealing new insights into genome stability and disease.
Area of Science:
- Molecular Biology
- Genetics
- Biochemistry
Background:
- Bloom syndrome protein (BLM) is a RecQ helicase crucial for genome stability.
- BLM is known to process structured DNA, but its behavior on single-stranded DNA (ssDNA) is less understood.
Purpose of the Study:
- To investigate the interaction of BLM with ssDNA.
- To characterize the phase separation capabilities of BLM on ssDNA.
- To understand the role of ATP and other ssDNA-binding proteins in BLM-ssDNA condensation.
Main Methods:
- In vitro phase separation assays.
- Biophysical measurements of ssDNA condensation force.
- Biochemical assays to study protein displacement.
Main Results:
- BLM exhibits intrinsic phase separation ability, forming co-condensates with ssDNA.
- ATP enhances BLM's ssDNA condensation capability, enabling compression against significant force (up to 60 pN).
- BLM dismantles Replication Protein A (RPA) and RAD51 from ssDNA, subsequently condensing the exposed ssDNA.
Conclusions:
- BLM possesses an uncharacterized ability to phase separate and condense ssDNA.
- This ssDNA condensation mechanism, potentiated by ATP, offers a new perspective on genome stability.
- Understanding BLM's ssDNA interactions may elucidate genomic instability in diseases linked to BLM overexpression.
Keywords:
Biomolecular CondensateBloom Syndrome ProteinHelicasePhase SeparationSingle-Molecule StudiesMore Related Videos
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