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Updated: Jul 23, 2025
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Monitoring Protein-RNA Interaction Dynamics In Vivo at High Temporal Resolution Using χCRAC
Published on: May 9, 2020
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Phase-separated ribosome-nascent chain complexes in genotoxic stress response
Orsolya Németh-Szatmári1, Bence Nagy-Mikó1, Ádám Györkei2,3
1Department of Biochemistry and Molecular Biology, University of Szeged, 6726 Szeged, Hungary.
RNA (New York, N.Y.)
|July 17, 2023
Summary
Assemblysomes, ribonucleoprotein complexes, are involved in DNA repair. These structures, found in yeast and human cells, dynamically respond to DNA damage, suggesting a role in cellular repair mechanisms.
Area of Science:
- Molecular Biology
- Cell Biology
- Biochemistry
Background:
- Assemblysomes are EDTA- and RNase-resistant ribonucleoprotein (RNP) complexes formed by paused ribosomes and nascent polypeptide chains.
- Previous studies identified assemblysomes associated with the proteasome subunit Rpt1 in yeast and human cells, highlighting the role of disordered N-terminal nascent chains.
Purpose of the Study:
- To identify novel assemblysome-associated RNPs using bioinformatics and experimental validation.
- To investigate the role of assemblysomes in DNA repair pathways and their response to DNA damage stimuli.
Main Methods:
- Bioinformatic analysis of yeast protein complexes to predict N-terminal disorder propensity.
- Experimental validation using yeast Sgs1 DNA helicase and human BLM helicase.
- RNA sequencing of assemblysome-associated RNAs.
- Transmission electron microscopy to visualize cellular structures.
Main Results:
- Bioinformatics predicted enrichment of DNA repair proteins among potential assemblysome components.
- Nascent Sgs1 chains form assemblysomes, and SGS1 mRNA dynamically shifts upon UV exposure.
- Human BLM helicase was identified in assemblysomes, and mRNAs for DNA repair proteins were enriched.
- 1,6-hexanediol disrupted assemblysome-like structures and increased sensitivity to X-ray treatment.
Conclusions:
- Assemblysomes are associated with DNA repair proteins in both yeast and human cells.
- Assemblysome dynamics are regulated by external stimuli, particularly DNA damage.
- These findings suggest assemblysomes play a significant role in the DNA damage response across species.
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