Cockayne Syndrome B protein selectively interacts and resolves intermolecular DNA G-quadruplex structures.
File(s)
Accepted version
Author(s)
Liano, Denise
Chowdhury, Souroprobho
Di Antonio, Marco
Type
Journal Article
Abstract
Guanine-rich DNA can fold into secondary structures known as G-quadruplexes (G4s). G4s can form from a single DNA strand (intramolecular) or from multiple DNA strands (intermolecular), but studies on their biological functions have been often limited to intramolecular G4s, owing to the low probability of intermolecular G4s to form within genomic DNA. Herein, we report the first example of an endogenous protein, Cockayne Syndrome B (CSB), that can bind selectively with picomolar affinity toward intermolecular G4s formed within rDNA while displaying negligible binding toward intramolecular structures. We observed that CSB can selectively resolve intermolecular over intramolecular G4s, demonstrating that its selectivity toward intermolecular structures is also reflected at the resolvase level. Immunostaining of G4s with the antibody BG4 in CSB-impaired cells (CS1AN) revealed that G4-staining in the nucleolus of these cells can be abrogated by transfection of viable CSB, suggesting that intermolecular G4s can be formed within rDNA and act as binding substrate for CSB. Given that loss of function of CSB elicits premature aging phenotypes, our findings indicate that the interaction between CSB and intermolecular G4s in rDNA could be of relevance to maintain cellular homeostasis.
Date Issued
2021-12-15
Date Acceptance
2021-11-18
Citation
Journal of the American Chemical Society, 2021, 143 (49), pp.20988-21002
ISSN
0002-7863
Publisher
American Chemical Society
Start Page
20988
End Page
21002
Journal / Book Title
Journal of the American Chemical Society
Volume
143
Issue
49
Copyright Statement
© 2021 American Chemical Society. This document is the Accepted Manuscript version of a Published Work that appeared in final form in Journal of the American Chemical Society, after peer review and technical editing by the publisher. To access the final edited and published work see https://pubs.acs.org/doi/10.1021/jacs.1c10745
Sponsor
Biotechnology and Biological Sciences Research Council (BBSRC)
Grant Number
BB/R011605/1
Subjects
03 Chemical Sciences
General Chemistry
Publication Status
Published
Date Publish Online
2021-12-02