University of Leicester
Browse
29-Bhogadia-Frontiers.pdf (3.95 MB)

Biophysical characterisation of the Bcl-x pre-mRNA and binding specificity of the ellipticine derivative GQC-05: Implication for alternative splicing regulation.

Download (3.95 MB)
journal contribution
posted on 2022-10-06, 09:02 authored by Mohammed Bhogadia, Beth Stone, Rafael Del Villar Guerra, Frederick W Muskett, Sudipta Ghosh, Andrea Taladriz-Sender, Glenn A Burley, Ian C Eperon, Andrew J Hudson, Cyril Dominguez
The BCL2L1 gene expresses two isoforms of Bcl-x protein via the use of either of two alternative 5' splice sites (5'ss) in exon 2. These proteins have antagonistic actions, Bcl-XL being anti-apoptotic and Bcl-XS pro-apoptotic. In a number of cancers the Bcl-XL isoform is over-expressed, resulting in cancer cell survival and growth, so switching splicing to the Xs isoform could have therapeutic benefits. We have previously proposed that a putative G-quadruplex (G4) exists downstream of the XS 5'ss and shown that the ellipticine derivative GQC-05, a previously identified DNA G4-specific ligand, induces an increase in the XS/XL ratio both in vitro and in cells. Here, we demonstrate that this G4 forms in vitro and that the structure is stabilised in the presence of GQC-05. We also show that GQC-05 binds RNA non-specifically in buffer conditions, but selectively to the Bcl-x G4 in the presence of nuclear extract, highlighting the limitations of biophysical measurements taken outside of a functional environment. We also demonstrate that GQC-05 is able to shift the equilibrium between competing G4 and duplex structures towards the G4 conformation, leading to an increase in accessibility of the XS 5'ss, supporting our previous model on the mechanism of action of GQC-05.

Funding

Regulation of alternative splicing by G-quadruplexes: molecular mechanisms and tools to manipulate gene expression

Biotechnology and Biological Sciences Research Council

Find out more...

University of Leicester, College of Life Sciences PhD scholarship

History

Author affiliation

he Leicester Institute of Structural and Chemical Biology, Department of Chemistry, University of Leicester

Version

  • VoR (Version of Record)

Published in

Frontiers in molecular biosciences

Volume

9

Pagination

943105

Publisher

Frontiers Media SA

issn

2296-889X

eissn

2296-889X

Copyright date

2022

Available date

2022-10-06

Spatial coverage

Switzerland

Language

eng

Usage metrics

    University of Leicester Publications

    Categories

    Licence

    Exports

    RefWorks
    BibTeX
    Ref. manager
    Endnote
    DataCite
    NLM
    DC