Piotr Ziolkowski

Meiotic cohesin RAD21L shapes 3D genome structure and transcription in the male germline Deletion of the meiotic subunit RAD21L alters 3D chromatin structure and transcription in the mammalian male germ line.

🚨 New from our lab in #ScienceAdvances!

RAD21L cohesin acts as both a 3D genome architect and a transcriptional gatekeeper in the male germline. Its loss disrupts both structure and function—highlighting the tight link between genome folding and gene regulation

www.science.org/doi/10.1126/...

Sure!!! Meiosis rules!
Fingers crossed for your paper 🤞

A great story from @chloegirard.bsky.social, confirming and extending our findings on how interhomolog polymorphism shapes crossover distribution in plants 🌱

List otwarty do Prezydenta RP, Marszałka Sejmu RP, Marszałka Senatu RP,  Prezesa Rady Ministrów oraz Wiceprezesów Rady Ministrów w sprawie finansowania nauki, w tym zwłaszcza Narodowego Centrum Nauki Szanowni Państwo, W niniejszej petycji prezentujemy List otwarty, który będzie wysłany do Kancelarii Prezydenta, Marszałków Sejmu i Senatu, Prezesa Rady Ministr&oacut...

Please consider signing a petition to increase the spending on science in Poland / List otwarty w sprawie finansowania nauki, w tym @ncn.gov.pl www.petycjeonline.com/list_otwarty...

🚀 We’re hiring a Postdoc!

Join our group in Poznan, Poland to study meiotic crossover recombination in plants 🌱 Highly motivated & enthusiastic candidates are welcome!
📅 Deadline: Nov 1, 2025

🔗 ibmib.web.amu.edu.pl/wp-content/uploads/2025/09/Postdoc_position-2025-Ziolkowskis-Lab.pdf

Holliday junction–ZMM protein feedback enables meiotic crossover assurance - Nature Holliday junctions maintain chromosome synapsis to enable crossover assurance in budding yeast.

Holliday junction–ZMM feedback ensures meiotic crossover assurance in yeast! Great work from the Joao Matos lab!
👉 www.nature.com/articles/s41...

Protecting double Holliday junctions ensures crossing over during meiosis - Nature Conditional ablation experiments show that key components of the synaptonemal complex protect double Holliday junction recombination intermediates to ensure their resolution into crossover products, which are required for accurate chromosome segregation during meiosis.

Fantastic work coming out of Neil Hunter’s lab! www.nature.com/articles/s41...

Thrilled to see our paper featured on the cover!!! 🎉🌽

Thank you so much, Ian! 🙏 I’m really happy I had the chance to work with you to discover this phenomenon ✨, and now to confirm it in a crop as well! 🌽🎉

Thank you so much!

Hybridization and introgression are major evolutionary processes. Since the 1940s, the prevailing view has been that they shape plants far more than animals. In our new study (www.science.org/doi/10.1126/...
), we find the opposite: animals exchange genes more, and for longer, than plants

Long-read detection of transposable element mobilization in the soma of hypomethylated Arabidopsis thaliana individuals - Genome Biology Background Because transposable elements (TEs) can cause heritable genetic changes, past work on TE mobility in Arabidopsis thaliana has mostly focused on new TE insertions in the germline of hypometh...

Paper led by @movillome.bsky.social on unbiased detection of (somatic) #TE insertions in #Arabidopsis with @pacbio.bsky.social long reads out after peer review. Thanks to academic editor Leandro Quadrana for shepherding it through the review process.
#plantscience
link.springer.com/article/10.1...?

A three year postdoctoral position is available in my group, investigating plant centromere structure, function and evolution @camplantsci.bsky.social
www.jobs.cam.ac.uk/job/51488/

Sexual selection drives the speciation of lineages with contrasting mating systems Repeated shifts in ecological strategies often lead to consistent speciation patterns across phylogenies. One example is the transition from outcrossi…

Very happy to have contributed to this collaborative work, with main drivers Marion Orsucci and Adrien Sicard:
Sexual selection drives the speciation of lineages with contrasting mating systems: www.sciencedirect.com/science/arti...

Plants repress ROS1 expression to attenuate heat-induced transposon burst - Nature Plants Plants suppress the DNA demethylase ROS1 under heat stress to limit transposon activation, preventing genome instability. This conserved mechanism balances stress adaptation with genome protection.

Here’s an interesting new paper on ROS1, an enzyme that removes DNA methylation and that is POSITIVELY controlled by DNA methylation.
It’s repression during heat stress 🥵🌱 is crucial to suppress transposon mobility! 🧬
www.nature.com/articles/s41...

Aneuploidy is the leading cause of pregnancy loss. In work led by @saracarioscia.bsky.social and @aabiddanda.bsky.social, we reanalyzed genetic testing data from 139,416 IVF embryos to discover variants associated with recombination phenotypes and aneuploidy risk. www.medrxiv.org/content/10.1...

Cryogenic electron microscopy has been used to determine the detailed structure of an intermediate state called a “D-loop” that forms when strands of DNA are exchanged during homologous recombination.
buff.ly/pZZfIso

Constraints on chromosome evolution revealed by the 229 chromosome pairs of the Atlas blue butterfly The genome of the Atlas blue butterfly contains ten times more chromosomes than most butterflies, and more than any other known diploid animal. Wright et al. show that this extraordinary karyotype is ...

How many chromosomes can an animal have?

In our paper out now in @currentbiology.bsky.social we show that the Atlas blue butterfly has 229 chromosome pairs- the highest in diploid Metazoa! These arose by rapid autosome fragmentation while sex chromosomes stayed intact.
www.cell.com/current-biol...

Do you want to know how to live-image internal floral organs with confocal microscope for up to 2 weeks?
Check out our protocol:
bio-protocol.org/en/bpdetail?...
#Arabidopsis #Flower

Interesting approach!

Thrilled to share our latest work on meiotic recombination, where we mapped rates and distributions by sequencing thousands of individual sperm. This study was led by Stevan Novakovic and @caitlinharris.bsky.social , in collaboration with @davisjmcc.bsky.social and Cynthia Liu.

Thanks Wayne!🙏

Thrilled to see such a thoughtful commentary on our paper by Maria Cuacos & Stefan Heckmann 🙌 Many thanks! 🔬🙏

This work was made possible through a great collaboration with Mikhail Mikhailov from Moldova 🇲🇩 and the fantastic efforts of all co-authors – special thanks to @franz_boideau, @SzymanskaLejman and Vasile Botnari 👏🌱

Enhancing local meiotic crossovers in Arabidopsis and maize through juxtaposition of heterozygous and homozygous regions - Nature Plants This study discovered that locally confined DNA differences boost crossover rates in both Arabidopsis and maize, revealing a conserved mechanism that can accelerate plant breeding and trait introgress...

Breaking genetics news‼️🌱🌽 A natural DNA trick triples recombination in maize. What we first saw in Arabidopsis (@hendersi lab) a decade ago is now confirmed in crops—opening new doors for plant breeding. Published today in Nature Plants! More details 👉 www.nature.com/articles/s41...

Unlocking meiotic crossovers near plant centromeres Crossovers (COs) ensure proper chromosome segregation during meiosis and generate genetic diversity. COs are non-uniformly distributed along chromosomes and almost universally suppressed in centromere...

The identification of the very conserved CTF18, SGO2 and SPF2 as suppressors of centromere-proximal crossovers highlights the importance of cohesin turnover in this process and opens up new possibilities for plant breeding. Much more in the paper : www.biorxiv.org/content/10.1...

Monopolar orientation of kinetochores at meiosis is enforced by COHESINS and their regulators, CENP-C, and the deSUMOylase SPF2 The first division of meiosis is unique in its capacity to halve the ploidy of the future gametes. To this end, one key innovation compared to mitosis is the monopolar orientation of the pairs of sist...

Preprint Alert! 🚨🧬
Not one, but two preprints!

Meiotic orientation of kinetochore at meiosis is inforced by...[see below]
www.biorxiv.org/content/10.1...

and

Unlocking meiotic crossovers next to plant centromere
www.biorxiv.org/content/10.1...

#meiosis4ever
#everythingisconnected

a thread👇

A cytological framework of female meiosis in Arabidopsis Female and male meiosis often differ in many aspects, such as their duration and the frequency as well as the positioning of crossovers. However, studying female meiosis is often very challenging and ...

Six more years—plus a lot of blood, sweat, and tears—later, we are thrilled to finally share it: a cytological framework of female meiosis in Arabidopsis!

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

This is the result of several years of hard work by Wojtek Dziegielewski and @szymanskalejman.bsky.social, with important support from Anna Wilhelm and Karolina Hus.

‼️Can we tune crossover hotspot activity by targeting chromatin modifiers? Absolutely!💥
Our screen shows dCas9-JMJ14 represses crossovers at targeted sites, while VP64 boosts them!
🧬 Check our new preprint:
www.biorxiv.org/content/10.1...

#meiosis4ever #CRISPR #Arabidopsis