Aurele Piazza

Social DNAing June to Dec 2025

Are you ready for the 2nd half of 2025? Social DNAing is ready. Check out the speaker list and schedule! Sign up at www.cancer.columbia.edu/research/pro...

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Super excited to share my first preprint from @andersshansen.bsky.social Lab! We used MINFLUX to track chromatin (H2B-Halo and Fbn2 locus) at an unprecedented 200 μs, then combined it with SPT to span μs-minutes (H2B) or SPT & Super-Res Live-Cell Imaging (SRLCI) to span μs-hours (Fbn2)

How does replication shapes the 3D organization of chromosomes? Check out this new preprint from our colleagues @djost-physbiol.bsky.social that investigates this question using a full polymer model of the budding yeast genome + new S-phase Hi-C data. Congrats to the lead author Dario D'Asaro!

Call For Two Group Leader Positions - Strasbourg-Ville, Bas-Rhin (FR) job with IGBMC (Institut de Génétique et de Biologie Moléculaire et Cellulaire) | 12837602 The Institute of Genetics, Molecular and Cellular Biology (IGBMC) is seeking two outstanding group leaders to establish independent research teams.

Come start your lab in beautiful Strasbourg 🇫🇷 www.nature.com/naturecareer...

!! Postdoc position available to study homologous recombination in live cells through advanced microscopy analyses in a collaboration between our lab and Angela Taddei's lab, both at @institutcurie.bsky.social in Paris.
Apply to : job-ref-ib8q3lnnxn@emploi.beetween.com

Structural basis for DNA double-strand break sensing by human MRE11-RAD50-NBS1 and its TRF2 complex The MRE11-RAD50-NBS1 (MRN) complex is a central, multifunctional factor in the detection, signaling and nucleolytic processing of DNA double-strand breaks (DSBs). To clarify how human MRN binds generi...

Happy to share our latest pre-print!
We solved the cryoEM structures of human DNA repair factor MRN bound to DNA and to TRF2. Main work of Yilan, Filiz @filizkuybu.bsky.social and Hengjun. Great collab within the @sfb1361.bsky.social and @genecenter-lmu.bsky.social 🧬🔨
www.biorxiv.org/content/10.1...

*Lyon* #StandUpForScience
Place des Terreaux à 16h : Rassemblement. Cet événement est un acte de solidarité envers nos collègues américains.​ Ensemble, affirmons notre engagement en faveur d’une science indépendante, accessible à toutes et tous.​

Once upon a time, in the late 1800s, people in Japan got really into breeding mice.

Coloured mice. Patterned mice. Even mice that danced.

They became known as Japanese Fancy Mice, and that caught the attention of researchers in Europe and America, who imported them for study.

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Parasitic plasmids are anchored to inactive regions of eukaryotic chromosomes through a nucleosome signal | The EMBO Journal imageimageThe naturally occurring S. cerevisiae 2µ plasmid is one of few documented cases of eukaryotic plasmids, undergoing equal distribution between mother and daughter cells during mitosis. Using ...

Are you curious about eukaryotic plasmids?
PhD student Fabien Girard with Axel Cournac in the lab explore the positioning of plasmid 2u, one of these rare (known) episomes, in the budding yeast nucleus. The results were surprising.
#plasmids #chromatin #3Dgenome

www.embopress.org/doi/full/10....

Branching architecture limits the rate of somatic mutation accumulation in trees Trees are long-lived plants that develop complex, highly branched shoot systems as they grow. Their extended lifespan allows somatic mutations to accumulate along these branching structures, ultimatel...

A completely mind-blowing mechanism at the organism structural level to limit mutation accumulation www.biorxiv.org/content/10.1...

Yasmina will soon finish her PhD and be on the postdoc market: you know what you have to do! Many thanks to our funding source @erc.europa.eu for allowing us to carry out this work.

Finally, Yasmina could show that transcription also suppressed the formation of chromosomal rearrangements between repeated elements formed by recombination, independently of other recombination regulators.

D-loop suppression by transcription was independent of, and even more potent than conserved recombination regulators known to promote genome maintenance and suppress tumor formation in humans (such as BLM-TOP3-RMI and FANCM homologs).

It has implications for the CO/NCO repair outcome, and may provide a mechanistic basis for the biased NCO resolution in highly expressed genes in human meiosis. see bsky.app/profile/magd... @bvhalldorsson.bsky.social

Transcription orientation mattered: co-linear orientation suppressed D-loops more efficiently than head-on orientation: A more permissive orientation thus exists to repair DNA breaks in highly-transcribed genes, but by one end only.

By putting two donors in competition and transcribing only one of them, we could show that transcription suppressed D-loops in cis! In fact, it even redirected D-loops from the transcribed to the non-transcribed donor.

This effect of transcription could be induced and reversed in minutes, suggesting it reflected a direct effect of RNA PolII passage. Indeed, secondary effect of transcription (RNA, RNA:DNA hybrids, nuclear relocalization, endogenous TFs, …) were not involved in D-loop suppression.

We used a highly efficient DNA break induction system in budding yeast, and quantified D-loops (the earliest DNA joint molecule formed upon homology identification) formed at a donor whose transcriptional level could be manipulated. Transcription caused a massive drop of D-loops.

How do cells prioritize molecular machines working on DNA? With which functional consequences? Here bs-less Yasmina Djeghmoum discovered and characterized transcription-recombination priority rules, and their role in promoting genome maintenance. 🧵
www.biorxiv.org/content/10.1...

CTCF stall DNA 🧬 loop ➰ extrusion by cohesin -
but exactly how it pulls this off is a 'mechanistic mystery' (to cite @andersshansen.bsky.social, Nucleus, 2020).

We just preprinted 📜 a new study @biorxivpreprint.bsky.social that provides some answers to this enigma: www.biorxiv.org/content/10.1...

Centromere evolution isn't a sudden switch!

Our study shows centromere transitions are a step-by-step process driven by a combination of drift and selection. Discover how the kinetochore interface shapes this gradual change in our new preprint 🥳 doi.org/10.1101/2025.01.16.633479 🧵(1/8)

📢The 2025 MAYosis webinar series will be held on consecutive Wednesdays, May 7-28, at 4 pm CET (7 am PST; 12 am JST) meiosis.cornell.edu/mayoss2025/ Apply to give a talk (deadline is March 8, trainees and junior faculty only): tinyurl.com/47k3cjpn Registration is free: tinyurl.com/39rs53yv

Prolonged persistence of mutagenic DNA lesions in somatic cells - Nature Persistent DNA lesions can occur throughout the human lifespan and can remain in the genome of affected cells for several years and generate a substantial proportion of the mutational burden.

Building on our discovery of #LesionSegregation, @mikespencerchapman.bsky.social and colleagues from @sangerinstitute.bsky.social find that some DNA lesions can persist in humans for months or years!

"Prolonged persistence of mutagenic DNA lesions in somatic cells"
www.nature.com/articles/s41...

Hi-C Calibration by Chemically Induced Chromosomal Interactions The genome-wide chromosome conformation capture method, Hi-C, has greatly advanced our understanding of genome organization. However, its quantitative properties, including sensitivity, bias, and line...

Important independent calibration of Hi-C data:

www.biorxiv.org/content/10.1...

We hope you all had fantastic holidays and are ready for 2025! The GIIN webinars will restart next Tuesday, January 14th, with exciting talks from @labthoma.bsky.social and @stesantaguida.bsky.social ! Follow the zoom link to join: uniroma1.zoom.us/j/95149984403

Is chromatin ordered or disordered? It all depends on the linker DNA length.

Check our latest work with Mike Rosen and Sy Redding. We explore how changes in linker DNA length (as small as 1 bp) fine-tune chromatin structure, between order and disorder, and the properties of chromatin droplets

Ever wondered how transcription choreographs histone modifications? Our work reveals the basis of co-transcriptional H3K36me3 by SETD2. We visualize how a histone writer coordinates with the transcription machinery! This is the magnus opus of @jonmarkert.bsky.social!
tinyurl.com/setd2

Meiosis: Exploring diversity to discover the fundamentals Meiosis is an essential cell division for sexual reproduction and fertility across eukaryotes. It involves a series of tightly regulated processes, including entry into meiosis, pairing of homologs, …

Registration now open for the 2025 EMBO workshop on Meiosis! June 22-26, 2025, Engelberg, Switzerland.
Deadline for abstract submissions and registration is Feb 15th, 2025. Lots of speaker slots will be selected from abstracts, so apply now! meetings.embo.org/event/25-mei...

YouTube video by WEHImovies DNA Break Repair by Homologous Recombination (2024) Drew Berry wehi.tv

Delighted to publish my new molecular animation:

DNA Break Repair by Homologous Recombination

youtu.be/Xe-83tBcxhs