Structural investigation of pathogenic RFC1 AAGGG pentanucleotide repeats reveals a role of G-quadruplex in dysregulated gene expression in CANVAS

© The Author(s) 2024. Published by Oxford University Press on behalf of Nucleic Acids Research..

An expansion of AAGGG pentanucleotide repeats in the replication factor C subunit 1 (RFC1) gene is the genetic cause of cerebellar ataxia, neuropathy, and vestibular areflexia syndrome (CANVAS), and it also links to several other neurodegenerative diseases including the Parkinson's disease. However, the pathogenic mechanism of RFC1 AAGGG repeat expansion remains enigmatic. Here, we report that the pathogenic RFC1 AAGGG repeats form DNA and RNA parallel G-quadruplex (G4) structures that play a role in impairing biological processes. We determine the first high-resolution nuclear magnetic resonance (NMR) structure of a bimolecular parallel G4 formed by d(AAGGG)2AA and reveal how AAGGG repeats fold into a higher-order structure composed of three G-tetrad layers, and further demonstrate the formation of intramolecular G4s in longer DNA and RNA repeats. The pathogenic AAGGG repeats, but not the nonpathogenic AAAAG repeats, form G4 structures to stall DNA replication and reduce gene expression via impairing the translation process in a repeat-length-dependent manner. Our results provide an unprecedented structural basis for understanding the pathogenic mechanism of AAGGG repeat expansion associated with CANVAS. In addition, the high-resolution structures resolved in this study will facilitate rational design of small-molecule ligands and helicases targeting G4s formed by AAGGG repeats for therapeutic interventions.

Medienart:

E-Artikel

Erscheinungsjahr:

2024

Erschienen:

2024

Enthalten in:

Zur Gesamtaufnahme - volume:52

Enthalten in:

Nucleic acids research - 52(2024), 5 vom: 21. März, Seite 2698-2710

Sprache:

Englisch

Beteiligte Personen:

Wang, Yang [VerfasserIn]
Wang, Junyan [VerfasserIn]
Yan, Zhenzhen [VerfasserIn]
Hou, Jianing [VerfasserIn]
Wan, Liqi [VerfasserIn]
Yang, Yingquan [VerfasserIn]
Liu, Yu [VerfasserIn]
Yi, Jie [VerfasserIn]
Guo, Pei [VerfasserIn]
Han, Da [VerfasserIn]

Links:

Volltext

Themen:

63231-63-0
9007-49-2
CANVAS syndrome
DNA
EC 3.6.4.-
Journal Article
RNA
Replication Protein C

Anmerkungen:

Date Completed 22.03.2024

Date Revised 23.03.2024

published: Print

Citation Status MEDLINE

doi:

10.1093/nar/gkae032

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM367565803