David Monchaud

We keep on investigating the cellular properties of the molecular helicase PhpC we developed to unfold G-quadruplex #G4 DNA and RNA.

In this new preprint, we demonstrate its genoprotective properties, showing how PhpC mitigates G4-associated genetic instability.

👉 doi.org/10.64898/202...

The DNA damaging properties of the experimental G-quadruplex (G4) drug QN-302 are potentiated by the DNA repair inhibitor Olaparib and mitigated by the molecular helicase PhpC https://www.biorxiv.org/content/10.64898/2026.02.06.704351v1

Biocatalysts made of DNA, and G-quadruplex #G4 DNA in particular, have found a myriad of applications. But is there a real-life application reported so far?
Thrilled to report this long-awaited example with the remediation of industrial wastewater!
In @academic.oup.com
doi.org/10.1093/nsr/...

FYI: the molecular helicase PhpC we developped to unfold G-quadruplex #G4 DNA and RNA both in vitro (see: shorturl.at/Ep8Il) and in human cells (e.g., shorturl.at/ue7rV, shorturl.at/zsheP & shorturl.at/MfUKW) is now commercially available at Idylle @idylle-labs.bsky.social
👉 shorturl.at/efE5l

Happy to be one of these guys going down the White Dune before swimming 10k across the Dakhla bay.
4 days, 4 stages, 4 adventures.
Thank you Morocco Swim Trek 🙏
👉 moroccoswimtrek.com

How to recapitulate in vitro what happens in cells? Not easy!
We investigated how guanine (G)-rich sequences interact with one another to decipher G4-associated gene expression regulation
With Nanjing U & @polytechniqueparis.bsky.social
@cnrs.fr
In @narjournal.bsky.social: doi.org/10.1093/nar/...

A huge thank you to Jean-Louis Mergny, Jérome and Pascale @polytechniqueparis.bsky.social for organizing the "G-quadruplex (G4) made in France": two days filled with diverse and fascinating exchanges on the many facets of #G4 research!

Super proud of my team! They have simplified the synthesis of TASQs, enabling easier & faster access to these biomimetic G-quadruplex (G4) ligands used to image and identify cellular G4s.
The TASQs story: doi.org/10.1021/acs....
This new article @chemistryeurope.bsky.social: doi.org/10.1002/chem...

A novel biotechnological application for G4s, used for controlling the activity of a CRISPR-Cas12a device used for diagnosing human viral infection (HPV) in a spatio-temporal manner
Now in Anal. Chem. @pubs.acs.org
With Nanjing U. & @polytechniqueparis.bsky.social
@cnrs.fr
doi.org/10.1021/acs....

The photoMultiTASQ is a new molecular tool to investigate G-quadruplex #G4 biology, notably for identifying G4 binding proteins by Chem-CLIP (chemical cross-linking and isolation by pull-down)
In ACS Bio & Med Chem Au: doi.org/10.1021/acsb...
With @iphc-strasbourg.bsky.social (FR) & WIS Rehovot (IS)

Stimulating scientific days #ChemBioParis2025.
Super great to hear Shankar Balasubramanian speaking about G-quadruplex, Matthew Disney about ChemCLIP and Dan Nomura about MYC druggability, among many others
Kudos to @borisvauzeilles.bsky.social & the team for the organization chembioparis2025.com

Magnetic activation of spherical nucleic acids enables the remote control of synthetic cells - Nature Chemistry The programmability of synthetic cells, comprising lipid vesicles that are capable of imitating the structure and function of living cells, facilitates their application as drug delivery devices. Now,...

We’ve developed the first-ever method to control nucleic acid activity and gene-expressing synthetic cells with a deeply tissue penetrating alternating magnetic field 🧬 🧪 🧲!!!

Published in *Nature Chemistry*

Led by Ellen Parkes
@syncelleu.bsky.social #chemsky
www.nature.com/articles/s41...

What happens when a DNA-junction binding compound is lengthened? Intriguingly, the larger pi surfaces widen the range of junctions targeted! Just out in JBIC -congratulations to authors
Sam and Hannah -first paper from her MSc by research studies @uobchemistry.bsky.social
doi.org/10.1007/s007...

Honored to have been interviewed by Pour La Science, a wide-audience scientific magazine, to discuss the results from @simonelsasser.bsky.social / @puckknipscheer.bsky.social published in @science.org about how DNA repair proteins mold G-quadruplex #G4

👉 tinyurl.com/3k6pxu6d
(sorry, in French only)

Happy to describe a novel strategy to detect pollutants in food with a super high sensitivity, using G-quadruplex #G4 based biosensing devices.

A collaboration with the University of Nanjing (CN) and Polytechnique Palaiseau (FR)

Now in Anal. Chem. (@pubs.acs.org): doi.org/10.1021/acs....

Happy to describe a novel strategy to combat colorectal cancer by pharmacologically modulating G-quadruplex #G4 RNA found in dysregulated lncRNAs, using the molecular helicase PhpC.

A collaboration with ITTGN (India) and supported by @embo.org fellowships

Now in BMC Biol.: doi.org/10.1186/s129...

Ready for super-G4s? We have identified clusters of G4s in intergenic regions that act as super-enhancers in ovarian cancer cells, hence the name super-G4! These are de novo super-enhancers that are not underpinned by canonical epigenetic marks, supporting the epigenetic role of G4s rdcu.be/evXtf

RNA transcripts regulate G-quadruplex landscapes through G-loop formation G-quadruplexes (G4s) are prevalent DNA structures that regulate transcription but also threaten genome stability. How G4 dynamics are controlled remains poorly understood. Here, we report that RNA tra...

Excited our paper is out! G-quadruplex (G4) unwinding via an intricate G-loop assembly and disassembly mechanism maintains genome integrity. Pioneered by Koichi Sato with great collaborators Jing Lyu and @simonelsasser.bsky.social Check it out: www.science.org/doi/10.1126/science.adr0493 🧵(1/4)

A novel demonstration of the G-quadruplex #G4 unfolding properties of PhpC, a quite unique prototype of G4 unfolder (or molecular helicase) we developed in the lab

In collaboration with C. Cruz @ubeirainterior.bsky.social and R.H.E. Huson @westernu.bsky.social ‬

👉 doi.org/10.1016/j.ij...

Call for Expressions of Interest – MSCA Postdocs 2025
Join my group at CiQUS to work on “Selective DNA Junction Binders for Targeted Anticancer Therapy”.
Deadline: June 15
www.usc.es/ciqus/en/MSC...

#MSCA #CiQUS #DNAJunctions #Postdoc #ChemSky #ChemBioSky

The best of the best!
The core of our community on #DNA #RNA junctions during the first meeting #IMAJ1 including @biometalusc.bsky.social, @sebastien-britton.bsky.social, @christinecardin.bsky.social, @granzhan.bsky.social, Jean-Louis, Mark and many others
Thank you again for your participation!

It was an absolute thrill and a real pleasure to organize the first meeting on #DNA #RNA junctions in Paris.
Fantastic talks, lively discussions—and some excellent wine too! 🍷😁
A very promising beginning for this new community
Stay tuned—we’ll be back next year!
#IMAJ1 #CNRSchimie @cnrs.fr

Thank you Christine 🫠

The first IRN on Nucleic Acid Junctions meeting couldn’t have gone any better. Brilliant science, inspiring people, and a perfect atmosphere. Huge thanks to @dmonchaud.bsky.social for making it happen
#IMAJ1 #ChemSky #DNAjunctions

Thank you, Miguel!
It was great to have you all here in Paris. It was our first meeting, but it was so exciting and promising! I'm eager to repeat this beautiful experience next year, certainly in the UK! Stay tuned!
#DNA #DNAjunction #iMAJ #IRN

A phylogeny of the 7 ape genomes that have now been completed from "T2T", with Homer Simpson representing mankind.

A project five years in the making, we've now published complete "T2T" genomes for six additional ape species! It turns out that finishing (and analyzing) six genomes is slightly more work than one... doi.org/10.1038/s415...

RNA G-quadruplexes control mitochondria-localized mRNA translation and energy metabolism - Nature Communications Cancer cells rely on mitochondria for energy and macromolecule synthesis. Here, the authors show that RNA G-quadruplex dynamics, driven by oncogenic signals, regulate the translation of nuclear-encode...

Excited to present our new @naturecomms.bsky.social paper with Stefania Millevoi's lab on the role of #RNA G-quadruplex in mitochondrial RNA. We find that
#RG4 can be exploited to inhibit mitochondrial translation and disrupt #cancer cells proliferation.

www.nature.com/articles/s41...

We're thrilled to have contributed to this @naturecomms.bsky.social paper on the role of G-quadruplex #G4 in mitochondrial RNA
G4s can be targeted with ligands to inhibit mitochondrial translation and eventually functions, which jeopardizes cancer cells fate
This is huge!
👉 doi.org/10.1038/s414...

Thanks Yehuda! 🙏

G-quadruplex–stalled eukaryotic replisome structure reveals helical inchworm DNA translocation DNA G-quadruplexes (G4s) are non–B-form DNA secondary structures that threaten genome stability by impeding DNA replication. To elucidate how G4s induce replication fork arrest, we characterized fork ...

How do replisomes walk on DNA? And what happens when they run into a G-quadruplex? @sahilbatra.bsky.social and @benallwein.bsky.social provide unexpected insight in our latest paper with Richard Hite @mskcancercenter.bsky.social @science.org www.science.org/doi/10.1126/.... Congrats to all authors!