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Updated: Jun 13, 2025
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A G-quadruplex DNA-affinity Approach for Purification of Enzymatically Active G4 Resolvase1
Published on: March 18, 2017
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The RNA-binding protein PCBP1 modulates transcription by recruiting the G-quadruplex-specific helicase DHX9
Joseph A Q Karam1, Cécile Fréreux1, Bidyut K Mohanty2
1Department of Biochemistry and Molecular Biology, College of Medicine, Medical University of South Carolina, Charleston, South Carolina, USA.
The Journal of Biological Chemistry
|September 29, 2024
Summary
Polycytosine (poly(C)) binding protein 1 (PCBP1) binds DNA at gene start sites, regulating transcription. It interacts with helicases like DHX9 to control gene expression and R-loop processing.
Area of Science:
- Molecular Biology
- Gene Regulation
- Biochemistry
Background:
- Polycytosine (poly(C)) binding protein 1 (PCBP1) is known as an RNA and single-stranded DNA (ssDNA) binding protein.
- PCBP1's role in transcriptional regulation via its ssDNA binding capacity has been unclear.
Purpose of the Study:
- To investigate the role of PCBP1 in transcriptional regulation.
- To elucidate the mechanism by which PCBP1 influences gene expression.
Main Methods:
- Analysis of PCBP1 DNA binding sites.
- Investigation of PCBP1 interactions with helicases, including RNA Helicase A (DHX9).
- Assessment of PCBP1 depletion effects on R-loop processing and gene transcription.
Main Results:
- PCBP1 DNA binding sites are predominantly located at transcription start sites.
- PCBP1 regulates transcription, splicing, and translation.
- PCBP1 interacts with G-quadruplex resolving helicases and modulates DHX9 activity.
- PCBP1 depletion causes R-loop processing defects and transcriptional dysregulation.
Conclusions:
- PCBP1 plays a significant role in transcriptional regulation by binding to promoter regions.
- PCBP1 guides helicases to specific genomic loci to modulate transcription.
- PCBP1 is crucial for maintaining R-loop homeostasis and proper gene expression.
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