Jana Helsen
@helsenjana.bsky.social
Incoming Assistant Professor at the University of Geneva (Jan 2027), currently postdoctoral fellow at the labs of Gautam Dey and Gavin Sherlock.
Evolutionary cell biology, chromosomes, centromeres, and the occasional SciArt🧬🧪🎨
helsenlab.org
Evolutionary cell biology, chromosomes, centromeres, and the occasional SciArt🧬🧪🎨
helsenlab.org
Pinned
Jana Helsen
@helsenjana.bsky.social
· Jul 16
Helsen lab | chromosome and centromere evolution
The Helsen lab at the University of Geneva explores how centromeres and chromosomes evolve, diversify, and function across eukaryotes. Discover our latest publications, research team, and open positio...
helsenlab.org
I am starting my lab at the University of Geneva next January! Incredibly excited to soon be joining the MOCEL department as an Asst. Professor.
The lab will use evolutionary cell biology to study chromosomes, centromeres & speciation 🧬🔬🌱
Intrigued, want to join or collaborate?
🔗 helsenlab.org
The lab will use evolutionary cell biology to study chromosomes, centromeres & speciation 🧬🔬🌱
Intrigued, want to join or collaborate?
🔗 helsenlab.org
Looking to do a PhD in evolutionary cell biology, chromosomes & centromeres? 🧬🔬
The winter call for the UNIGE PhD recruitment is open, and my lab is among those recruiting through the Molecular Biosciences program!
🗓️ Apply by Nov 1st: lifesciencesphd.unige.ch
The winter call for the UNIGE PhD recruitment is open, and my lab is among those recruiting through the Molecular Biosciences program!
🗓️ Apply by Nov 1st: lifesciencesphd.unige.ch
University of Geneva - PhD School of Life Sciences | Welcome to the PhD School in Life Sciences at the Faculties of Medicine and Science
The University of Geneva Faculties of Medicine and Science join their forces to offer an outstanding study and research environment in Life Sciences. Highly motivated students with a Master’s degree o...
lifesciencesphd.unige.ch
October 8, 2026 at 8:49 AM
Looking to do a PhD in evolutionary cell biology, chromosomes & centromeres? 🧬🔬
The winter call for the UNIGE PhD recruitment is open, and my lab is among those recruiting through the Molecular Biosciences program!
🗓️ Apply by Nov 1st: lifesciencesphd.unige.ch
The winter call for the UNIGE PhD recruitment is open, and my lab is among those recruiting through the Molecular Biosciences program!
🗓️ Apply by Nov 1st: lifesciencesphd.unige.ch
Reposted by Jana Helsen
📣Our department is hiring a new group leader!📣
Want to start your team in a vibrant scientific environment in the center of Paris? I was very lucky to do that 10 years ago, reach out if you have any question.
Apply by December 18th:
jpi-recruitment-curie-umr3215-u934.curie.fr
Want to start your team in a vibrant scientific environment in the center of Paris? I was very lucky to do that 10 years ago, reach out if you have any question.
Apply by December 18th:
jpi-recruitment-curie-umr3215-u934.curie.fr
October 6, 2026 at 10:43 AM
📣Our department is hiring a new group leader!📣
Want to start your team in a vibrant scientific environment in the center of Paris? I was very lucky to do that 10 years ago, reach out if you have any question.
Apply by December 18th:
jpi-recruitment-curie-umr3215-u934.curie.fr
Want to start your team in a vibrant scientific environment in the center of Paris? I was very lucky to do that 10 years ago, reach out if you have any question.
Apply by December 18th:
jpi-recruitment-curie-umr3215-u934.curie.fr
Reposted by Jana Helsen
It took a while, but here we are. Our micDROP paper is out in @natcomms.nature.com, led by @atargt.bsky.social. She asked whether the sequence of a disordered region can self-recognize specifically. She measured this for ten IDRs in living yeast cells.
www.nature.com/articles/s41...
www.nature.com/articles/s41...
September 25, 2026 at 12:25 PM
It took a while, but here we are. Our micDROP paper is out in @natcomms.nature.com, led by @atargt.bsky.social. She asked whether the sequence of a disordered region can self-recognize specifically. She measured this for ten IDRs in living yeast cells.
www.nature.com/articles/s41...
www.nature.com/articles/s41...
Reposted by Jana Helsen
Out today in Nature: sex without crossovers.
Rhynchospora tenuis makes pollen, fertilises and sets seed, yet 0 crossovers in 10,997 pollen nuclei. Chromosome drive and ~87% seed abortion rebuild the mother's genotype, so the offspring are clones.
doi.org/10.1038/s415...
Rhynchospora tenuis makes pollen, fertilises and sets seed, yet 0 crossovers in 10,997 pollen nuclei. Chromosome drive and ~87% seed abortion rebuild the mother's genotype, so the offspring are clones.
doi.org/10.1038/s415...
September 16, 2026 at 4:19 PM
Out today in Nature: sex without crossovers.
Rhynchospora tenuis makes pollen, fertilises and sets seed, yet 0 crossovers in 10,997 pollen nuclei. Chromosome drive and ~87% seed abortion rebuild the mother's genotype, so the offspring are clones.
doi.org/10.1038/s415...
Rhynchospora tenuis makes pollen, fertilises and sets seed, yet 0 crossovers in 10,997 pollen nuclei. Chromosome drive and ~87% seed abortion rebuild the mother's genotype, so the offspring are clones.
doi.org/10.1038/s415...
Reposted by Jana Helsen
🚨 New preprint alert! 🚨
Choanoflagellates reorganize their global cytoskeletal architecture within seconds to explore confined microspaces. This is the main PhD work of the amazing @maitefreired.bsky.social www.biorxiv.org/content/10.6...
A tread 🧵⬇️
Choanoflagellates reorganize their global cytoskeletal architecture within seconds to explore confined microspaces. This is the main PhD work of the amazing @maitefreired.bsky.social www.biorxiv.org/content/10.6...
A tread 🧵⬇️
Rapid repurposing of microvillar content drives a flagellate-to-amoeboid switch in the closest relative of animals
Animal cells extensively remodel their cytoskeleton during differentiation and can notably switch between two major motility modes: flagellum-based swimming and actin-based crawling. We previously sho...
www.biorxiv.org
September 2, 2026 at 9:19 PM
🚨 New preprint alert! 🚨
Choanoflagellates reorganize their global cytoskeletal architecture within seconds to explore confined microspaces. This is the main PhD work of the amazing @maitefreired.bsky.social www.biorxiv.org/content/10.6...
A tread 🧵⬇️
Choanoflagellates reorganize their global cytoskeletal architecture within seconds to explore confined microspaces. This is the main PhD work of the amazing @maitefreired.bsky.social www.biorxiv.org/content/10.6...
A tread 🧵⬇️
Reposted by Jana Helsen
Our study on giant transposons Starship 🚀🧬 in the genome of the lichen fungus Xanthoria is now out in @pnas.org! What did we find out about Starships in #lichen fungi? 👇Updated thread below 🖥️ 🧪 🦠 🧫 #SymbioSky 1/6
www.pnas.org/doi/10.1073/...
www.pnas.org/doi/10.1073/...
August 11, 2026 at 7:31 PM
Our study on giant transposons Starship 🚀🧬 in the genome of the lichen fungus Xanthoria is now out in @pnas.org! What did we find out about Starships in #lichen fungi? 👇Updated thread below 🖥️ 🧪 🦠 🧫 #SymbioSky 1/6
www.pnas.org/doi/10.1073/...
www.pnas.org/doi/10.1073/...
Reposted by Jana Helsen
Freaking finally! A massive compilation of data that sat on various desks for almost a decade is finally out. On the positive side, gave me time to learn expansion microscopy and make Fig 1 www.science.org/doi/10.1126/...
Emergent metabolic parasitism driven by organelle sequestration
Chloroplast-stealing ciliates evolve, increasing reliance on their prey for all aspects of metabolism, including photosynthesis.
www.science.org
August 7, 2026 at 6:31 PM
Freaking finally! A massive compilation of data that sat on various desks for almost a decade is finally out. On the positive side, gave me time to learn expansion microscopy and make Fig 1 www.science.org/doi/10.1126/...
Reposted by Jana Helsen
Happy to share the final version of our study on the evolution of chromatin states across eukaryotes, out today in @natgenet.nature.com
Led by @crisnava.bsky.social and @seanamontgomery.bsky.social
www.nature.com/articles/s41...
Some highlights below
Led by @crisnava.bsky.social and @seanamontgomery.bsky.social
www.nature.com/articles/s41...
Some highlights below
Diversity and evolution of chromatin regulatory states across eukaryotes - Nature Genetics
This study introduces iChIP2, a low-input chromatin immunoprecipitation followed by sequencing method that profiles histone post-translational modifications (hPTMs) simultaneously across diverse eukar...
www.nature.com
August 3, 2026 at 9:08 AM
Happy to share the final version of our study on the evolution of chromatin states across eukaryotes, out today in @natgenet.nature.com
Led by @crisnava.bsky.social and @seanamontgomery.bsky.social
www.nature.com/articles/s41...
Some highlights below
Led by @crisnava.bsky.social and @seanamontgomery.bsky.social
www.nature.com/articles/s41...
Some highlights below
Reposted by Jana Helsen
📢 We're hiring a postdoc!
If you're passionate about microbial biosynthetic pathway elucidation and enzyme discovery we'd love to hear from you!
www.kuleuven.be/personeel/jo...
If you're passionate about microbial biosynthetic pathway elucidation and enzyme discovery we'd love to hear from you!
www.kuleuven.be/personeel/jo...
Postdoc Microbial Biochemistry: Biosynthetic Enzyme Discovery in Cable Bacteria
Elucidating the biosynthesis of a unique nickel-containing conductive structure for long-range electron transport in cable bacteria
www.kuleuven.be
July 28, 2026 at 4:18 PM
📢 We're hiring a postdoc!
If you're passionate about microbial biosynthetic pathway elucidation and enzyme discovery we'd love to hear from you!
www.kuleuven.be/personeel/jo...
If you're passionate about microbial biosynthetic pathway elucidation and enzyme discovery we'd love to hear from you!
www.kuleuven.be/personeel/jo...
Reposted by Jana Helsen
CRISPR-mediated centromere fission generates neochromosomes with distorted meiotic inheritance in Arabidopsis biorxiv.org/content/10.6... new preprint from us - includes changing the Arabidopsis karyotype from 5 -> 6 chromosomes using Cas9 & outcomes of 5/6 chromosome hybrid meiosis
July 25, 2026 at 8:11 AM
CRISPR-mediated centromere fission generates neochromosomes with distorted meiotic inheritance in Arabidopsis biorxiv.org/content/10.6... new preprint from us - includes changing the Arabidopsis karyotype from 5 -> 6 chromosomes using Cas9 & outcomes of 5/6 chromosome hybrid meiosis
Reposted by Jana Helsen
So happy to share our new paper out now in @natmicrobiol.nature.com! We establish Pirsonia-Coscinodiscus as a model pathosystem and uncover how this tiny parasite infects and kills bloom-forming marine diatoms 🌊🦠 rdcu.be/fuQyF
July 21, 2026 at 12:32 PM
So happy to share our new paper out now in @natmicrobiol.nature.com! We establish Pirsonia-Coscinodiscus as a model pathosystem and uncover how this tiny parasite infects and kills bloom-forming marine diatoms 🌊🦠 rdcu.be/fuQyF
I am starting my lab at the University of Geneva next January! Incredibly excited to soon be joining the MOCEL department as an Asst. Professor.
The lab will use evolutionary cell biology to study chromosomes, centromeres & speciation 🧬🔬🌱
Intrigued, want to join or collaborate?
🔗 helsenlab.org
The lab will use evolutionary cell biology to study chromosomes, centromeres & speciation 🧬🔬🌱
Intrigued, want to join or collaborate?
🔗 helsenlab.org
Helsen lab | chromosome and centromere evolution
The Helsen lab at the University of Geneva explores how centromeres and chromosomes evolve, diversify, and function across eukaryotes. Discover our latest publications, research team, and open positio...
helsenlab.org
July 16, 2026 at 7:01 AM
I am starting my lab at the University of Geneva next January! Incredibly excited to soon be joining the MOCEL department as an Asst. Professor.
The lab will use evolutionary cell biology to study chromosomes, centromeres & speciation 🧬🔬🌱
Intrigued, want to join or collaborate?
🔗 helsenlab.org
The lab will use evolutionary cell biology to study chromosomes, centromeres & speciation 🧬🔬🌱
Intrigued, want to join or collaborate?
🔗 helsenlab.org
Reposted by Jana Helsen
A tenure-track research position is available for application at the Westerdijk Fungal Biodiversity Institute @westerdijkinst.bsky.social located in Utrecht Science Park in the Netherlands. Please share with colleagues and see the link below for more info: wi.knaw.nl/news/details...
Loading...
wi.knaw.nl
July 8, 2026 at 10:36 PM
A tenure-track research position is available for application at the Westerdijk Fungal Biodiversity Institute @westerdijkinst.bsky.social located in Utrecht Science Park in the Netherlands. Please share with colleagues and see the link below for more info: wi.knaw.nl/news/details...
Reposted by Jana Helsen
Multinucleate cells challenge deeply-held assumptions about complexity, ecological success and evolution. Postdoc extraordinaire and gifted writer @mrosjac.bsky.social tackles this subject with aplomb - tell us what you think!
www.sciencedirect.com/science/arti...
@currentbiology.bsky.social
www.sciencedirect.com/science/arti...
@currentbiology.bsky.social
Multinucleation as a recurring evolutionary strategy for scaling and plasticity
Multinucleate cells — single cells containing multiple nuclei in a shared cytoplasm — are found across the eukaryotic tree of life. Having evolved ind…
www.sciencedirect.com
May 18, 2026 at 4:52 PM
Multinucleate cells challenge deeply-held assumptions about complexity, ecological success and evolution. Postdoc extraordinaire and gifted writer @mrosjac.bsky.social tackles this subject with aplomb - tell us what you think!
www.sciencedirect.com/science/arti...
@currentbiology.bsky.social
www.sciencedirect.com/science/arti...
@currentbiology.bsky.social
Reposted by Jana Helsen
What’s better than seeing your paper in print? Sharing the table of contents with @thibautbrunet.bsky.social @maxhaase.bsky.social @pontus-skoglund.bsky.social 🤩
@nature.com @helsenjana.bsky.social @gsherloc.bsky.social @kausthubh.bsky.social
@nature.com @helsenjana.bsky.social @gsherloc.bsky.social @kausthubh.bsky.social
March 26, 2026 at 9:15 PM
What’s better than seeing your paper in print? Sharing the table of contents with @thibautbrunet.bsky.social @maxhaase.bsky.social @pontus-skoglund.bsky.social 🤩
@nature.com @helsenjana.bsky.social @gsherloc.bsky.social @kausthubh.bsky.social
@nature.com @helsenjana.bsky.social @gsherloc.bsky.social @kausthubh.bsky.social
Reposted by Jana Helsen
Final version @nature.com of our paper describing unconventional multicellular development in a choanoflagellate inhabiting an extreme environment. A ton of new data since the first @biorxivpreprint.bsky.social preprint (which we've kept updating).
A brief 🧵 (carried over from the old place)
A brief 🧵 (carried over from the old place)
A study in Nature shows that the single-celled form of a tiny, aquatic organism can turn into a multicellular version by three different routes. The discovery adds insight to the possible origins of multicellular life, suggesting a previously unrecognized degree of flexibility. 🧪
Clonal-aggregative multicellularity tuned by salinity in a choanoflagellate - Nature
The choanoflagellate Choanoeca flexa forms motile and contractile cell monolayers purely clonally, purely aggregatively or through a combination of both processes depending on environmental conditions.
go.nature.com
February 28, 2026 at 8:13 AM
Final version @nature.com of our paper describing unconventional multicellular development in a choanoflagellate inhabiting an extreme environment. A ton of new data since the first @biorxivpreprint.bsky.social preprint (which we've kept updating).
A brief 🧵 (carried over from the old place)
A brief 🧵 (carried over from the old place)
Really nice to see @marstonlab.bsky.social's News & Views piece cover the evolution of budding yeast centromeres in @nature.com. Check it out for a clear and concise breakdown of @maxhaase.bsky.social’s new paper and ours! 🧬
I had fun writing this N&Vs on two fascinating new papers on centromere evolution in yeast. If you’re interested in how centromeres adapt yet stay functional, here’s my take. rdcu.be/e6DD0 @nature.com @gautamdey.bsky.social @gsherloc.bsky.social @helsenjana.bsky.social @maxhaase.bsky.social
How can fast-evolving DNA retain a fundamental function in cell division? | Nature
In a dividing cell, chromosome pairs are pulled apart thanks to attachment sites called centromeres. Yeast genomes reveal key steps in how centromeres have evolved. In a dividing cell, chromosome pairs are pulled apart thanks to attachment sites called centromeres. Yeast genomes reveal key steps in how centromeres have evolved.
rdcu.be
March 4, 2026 at 8:29 AM
Really nice to see @marstonlab.bsky.social's News & Views piece cover the evolution of budding yeast centromeres in @nature.com. Check it out for a clear and concise breakdown of @maxhaase.bsky.social’s new paper and ours! 🧬
Reposted by Jana Helsen
I had fun writing this N&Vs on two fascinating new papers on centromere evolution in yeast. If you’re interested in how centromeres adapt yet stay functional, here’s my take. rdcu.be/e6DD0 @nature.com @gautamdey.bsky.social @gsherloc.bsky.social @helsenjana.bsky.social @maxhaase.bsky.social
How can fast-evolving DNA retain a fundamental function in cell division? | Nature
In a dividing cell, chromosome pairs are pulled apart thanks to attachment sites called centromeres. Yeast genomes reveal key steps in how centromeres have evolved. In a dividing cell, chromosome pairs are pulled apart thanks to attachment sites called centromeres. Yeast genomes reveal key steps in how centromeres have evolved.
rdcu.be
March 3, 2026 at 9:41 PM
I had fun writing this N&Vs on two fascinating new papers on centromere evolution in yeast. If you’re interested in how centromeres adapt yet stay functional, here’s my take. rdcu.be/e6DD0 @nature.com @gautamdey.bsky.social @gsherloc.bsky.social @helsenjana.bsky.social @maxhaase.bsky.social
Reposted by Jana Helsen
Our paper is now out in Nature:
“Ancient co-option of LTR retrotransposons as yeast centromeres”
www.nature.com/articles/s41...
A short thread on how retrotransposons helped give rise to yeast point centromeres.
1/14
“Ancient co-option of LTR retrotransposons as yeast centromeres”
www.nature.com/articles/s41...
A short thread on how retrotransposons helped give rise to yeast point centromeres.
1/14
Ancient co-option of LTR retrotransposons as yeast centromeres - Nature
Evolutionarily related ‘proto-point’ centromeres providing resolution to the evolutionary origins of point centromeres are identified in yeast, and comparison shows they evolved in an ancestor with re...
www.nature.com
February 18, 2026 at 4:03 PM
Our paper is now out in Nature:
“Ancient co-option of LTR retrotransposons as yeast centromeres”
www.nature.com/articles/s41...
A short thread on how retrotransposons helped give rise to yeast point centromeres.
1/14
“Ancient co-option of LTR retrotransposons as yeast centromeres”
www.nature.com/articles/s41...
A short thread on how retrotransposons helped give rise to yeast point centromeres.
1/14
Reposted by Jana Helsen
📢 Three new #bioRxiv preprints from our team on holocentric chromosomes.
Together, they connect centromere repeat evolution, karyotype dynamics, and meiotic recombination outcomes, revealing how holocentric genomes evolve and function. 🧬👇
Together, they connect centromere repeat evolution, karyotype dynamics, and meiotic recombination outcomes, revealing how holocentric genomes evolve and function. 🧬👇
January 21, 2026 at 2:45 PM
📢 Three new #bioRxiv preprints from our team on holocentric chromosomes.
Together, they connect centromere repeat evolution, karyotype dynamics, and meiotic recombination outcomes, revealing how holocentric genomes evolve and function. 🧬👇
Together, they connect centromere repeat evolution, karyotype dynamics, and meiotic recombination outcomes, revealing how holocentric genomes evolve and function. 🧬👇
Reposted by Jana Helsen
🔬🔦Our Imaging spotlight from @hiralshah.bsky.social & team highlights their U-ExM atlas of planktonic eukaryotes, including details on how you can explore this wonderful resource. Plus, check out Hiral’s top tips on getting started with expansion microscopy.
focalplane.biologists.com/2026/01/20/i...
focalplane.biologists.com/2026/01/20/i...
Imaging spotlight: U-ExM atlas of microbial eukaryotes - FocalPlane
Imaging spotlight: U-ExM atlas of microbial eukaryotes - News
focalplane.biologists.com
January 20, 2026 at 1:26 PM
🔬🔦Our Imaging spotlight from @hiralshah.bsky.social & team highlights their U-ExM atlas of planktonic eukaryotes, including details on how you can explore this wonderful resource. Plus, check out Hiral’s top tips on getting started with expansion microscopy.
focalplane.biologists.com/2026/01/20/i...
focalplane.biologists.com/2026/01/20/i...
Reposted by Jana Helsen
I am happy to share that my postdoctoral work in the @gerlichlab.bsky.social at @imbavienna.bsky.social is finally out 🎉!
Our study reveals how cohesin guides focused and accurate homology search.
Read more 👉 www.science.org/doi/10.1126/...
Follow along for key insights and updates! 🧵
Our study reveals how cohesin guides focused and accurate homology search.
Read more 👉 www.science.org/doi/10.1126/...
Follow along for key insights and updates! 🧵
Cohesin guides homology search during DNA repair using loops and sister chromatid linkages
Accurate repair of DNA double-strand breaks (DSBs) is essential for genome stability, and defective repair underlies diseases such as cancer. Homologous recombination uses an intact homologous sequenc...
www.science.org
December 4, 2025 at 8:18 PM
I am happy to share that my postdoctoral work in the @gerlichlab.bsky.social at @imbavienna.bsky.social is finally out 🎉!
Our study reveals how cohesin guides focused and accurate homology search.
Read more 👉 www.science.org/doi/10.1126/...
Follow along for key insights and updates! 🧵
Our study reveals how cohesin guides focused and accurate homology search.
Read more 👉 www.science.org/doi/10.1126/...
Follow along for key insights and updates! 🧵
Reposted by Jana Helsen
Nature research paper: Progressive coevolution of the yeast centromere and kinetochore
go.nature.com/4rtOuhu
go.nature.com/4rtOuhu
Progressive coevolution of the yeast centromere and kinetochore - Nature
Thousands of centromeres were identified and tracked across two major fungal clades, showing that new centromeres spread progressively and that the kinetochore acts as a filter to determine which new centromere variants are tolerated.
go.nature.com
December 3, 2025 at 2:14 PM
Nature research paper: Progressive coevolution of the yeast centromere and kinetochore
go.nature.com/4rtOuhu
go.nature.com/4rtOuhu
Reposted by Jana Helsen
Our story on the kinetochore composition of the ciliate Tetrahymena thermophila is out now on bioRxiv! We find surprisingly many orthologs of conventional kinetochore components, but also components that have very different evolutionary origins. A 🧵 (1/11)
Check it out here: tinyurl.com/4ectm9x4
Check it out here: tinyurl.com/4ectm9x4
tinyurl.com
December 1, 2025 at 2:06 PM
Our story on the kinetochore composition of the ciliate Tetrahymena thermophila is out now on bioRxiv! We find surprisingly many orthologs of conventional kinetochore components, but also components that have very different evolutionary origins. A 🧵 (1/11)
Check it out here: tinyurl.com/4ectm9x4
Check it out here: tinyurl.com/4ectm9x4
Reposted by Jana Helsen
Excellent experience at the @embo.org Sectorial Meeting on Evolution. Cozy talks on chalk talk format together with different motivated colleagues, getting feedback and super nice conversations. Had the chance to invite the junior PI @pablo-villa.bsky.social Loved the experience! EMBO
December 2, 2025 at 9:12 AM
Excellent experience at the @embo.org Sectorial Meeting on Evolution. Cozy talks on chalk talk format together with different motivated colleagues, getting feedback and super nice conversations. Had the chance to invite the junior PI @pablo-villa.bsky.social Loved the experience! EMBO