Roux Lab, Geneva

We are also very excited to present the first 'in curvo' nematics of each actin layer in the same Hydra ! 🤩 Amazing work by NeMo's dad @kandreadis.bsky.social and the fantastic imaging by @oriolmb.bsky.social from the @rouxlab.bsky.social, to illustrate the possible use of NeMo.

NeMo is finally out! 🐟 We present our new method to peel cellular layers and extract their nematics. If you're wondering what a fish has to do with curved nematics, check out the thread and the publication 👀👇🏼 arxiv.org/html/2609.12...

Fantastic collaboration with the Kaksonen lab, amazing work from Anne-Laure Boinet with some truly surprising result! Congrats to all contributors!

@mhakala.bsky.social shows that HRS forms bidimensional condensates onto endosomal membranes to flatten clathrin/ESCRT-0, an observation unexplained since the 2000s. Thx to Kukulski lab, @stefvass.bsky.social @colomlab.bsky.social @kaksonen.bsky.social @mishakudryashev.bsky.social rdcu.be/fihKk

Congrats to Nicolas, Mathieu ad Claire for this important achievement. This will help the community tremendously!

New method paper out today on FLIM analysis with Flipper-TR. We discuss fitting strategies, common pitfalls, and quantitative interpretation for measurements. First corresponding/last authorship for me! Free link: authors.elsevier.com/a/1me2hHRzCb... Thanks to @rouxlab.bsky.social and Tithi Mandal!

This monday we had our monthly Sciences Club. Here Cesar Bernat is showing his work on CHMP1A in mammalian cells in the @rouxlab.bsky.social ! #postdoclife

I am super happy and honored to see some of my movies making it into the NYT. I hope everybody enjoys watching them go as much as I do!

So grateful to @epimechfc.bsky.social for citing our work! It’s a classic from the lab, forever thanks to @colomlab.bsky.social

thanks for showing this movie! The gradients of tension reorient while migrating cells change directions.

All what you want to know about flipper probes without daring asking

Exhaustive guide about Flipper TR FLIM analysis we made with Tithi Mandal and @rouxlab.bsky.social very soon in the methods in Enzymology series edited by @jeremybaskin.bsky.social

You should also read Juanma’s paper, which visualizes membrane tension gradients in migrating and non-migrating cells! rdcu.be/e2u20 It also shows that flipper truly reports tension, but that response varies with lipid composition.

Roffay, C., Molinard, G., ..., & Roux, A. (2021). Passive coupling of membrane tension and cell volume during active response of cells to osmosis. Proceedings of the National Academy of Sciences of the United States of America, 118(47), e2103228118. #EpithelialMechanics buff.ly/r1Hj7F6

Guillaume Pernollet shows that epithelial cells adjust their shape to locally flatten, forming scutoids for any geometry, changing our view of cell packing. Thanks to all! @clairedessalles.bsky.social @juanmagararc.bsky.social @sciencesunige.bsky.social www.biorxiv.org/content/10.6...

@marineluciano.bsky.social recreates intestinal Villi geometry by growing epithelial cells on wavy rolling substrates. Unexpected intrication of curvature effects is observed. Thanks to all! @caterinatomba.bsky.social @sgabriele.bsky.social @sciencesunige.bsky.social www.biorxiv.org/content/10.6...

Paper alert: Our study led by @evapillai.bsky.social and @sudimukherjee.bsky.social showing that mechanical properties of the #brain actively shape the molecular landscape during development and #axonpathfinding is finally out! www.nature.com/articles/s41... @pdncambridge.bsky.social @fau.de @MPZPM

A great start to 2026! It was a pleasure to present my work on membrane asymmetry in the @rouxlab.bsky.social at the Geneva Chemistry and Biochemistry Days. It was also an honor to receive the Best Oral Presentation in Life Science!

A fantastic opportunity to work in Geneva if you are in the field of origins of life!

Today, our animation synthesizing decades of research on actin-mediated endocytosis in budding yeast was published: journals.biologists.com/jcs/article/... The result of a fantastic Iwasa-Drubin lab collaboration. @margotriggi.bsky.social @jiwasa.bsky.social movie.biologists.com/video/10.124...

All credits to the dreamteam that made this possible! what a pleasure and honor working with these people! 🥰 @diorgeps.bsky.social @mhakala.bsky.social @juanmagararc.bsky.social @joshuatran.bsky.social @mudgal17.bsky.social @Carlos Marcuello @Andrea Merino

The crucial test: We fused Heimdall Hofund to a fission-defective yeast ESCRT-III protein (Did2). This chimera restored Mup1 trafficking to vacuoles back to wt! A short amphipathic helix, present in Asgard and retained as fragments in eukaryotes, acts as a minimal membrane fission trigger!

Eukaryotic ESCRT-IIIA paralogs, known to form heteropolymers, retain Hofund elements at their N-termini. In yeast, mutating these elements blocks ESCRT-III-dependent Mup1 transport to vacuoles. So these elements matter in eukaryotes too.

Is this Asgard-specific, or conserved with their eukaryotic paralogs? Hard to tell, since the exact molecular mechanism of fission by eukaryotic ESCRT-III remains blurry, probably due to its complexity. Let’s figure it out!

Meet Hofund, the N-terminal amphipathic helix of 15 aa in Heimdall ESCRT-IIIA (named after Heimdall’s sword). How do we know Hofund is the molecular trigger for fission? Remove Hofund → ESCRT-IIIA loses fission activity. Add Hofund alone → uncontrolled fission.

Through membrane fission! We show in vitro that the Asgard Heimdallarchaeota (Heimdall) ESCRT-IIIA subunit is inherently capable of triggering fission upon subunit turnover driven by ATP hydrolysis by Vps4. And the key question: what actually destabilizes the membrane when ESCRT-IIIA turns over?

In a recent work, @buzzbaum.bsky.social and colleagues showed an Asgard archaeon with internal vesicles. www.biorxiv.org/content/10.1... How might Asgard ESCRT-III have contributed to compartmentalization?

Fantastic work from Javier @javierespadas.bsky.social in collaboration with @buzzbaum.bsky.social and @kaksonen.bsky.social labs, thank you Chris Toret, thank you Diorge @diorgeps.bsky.social!

Thanks to all the team at @rouxlab.bsky.social and abroad: @pauguillamat.bsky.social @caterinatomba.bsky.social @giodang.bsky.social @colomlab.bsky.social @lizhinde.bsky.social @javierespadas.bsky.social and many more

Overall, the work shows that tension gradients arise from the combination of actin dynamics and strong cell–substrate adhesion, rather than from migration itself. Link: rdcu.be/eRTQA

We accompanied this dynamic live Flipper-TR FLIM imaging with lipid diffusion analysis, spatial lipidomics (shown below), and cool in vitro reconstitutions of tension gradients using supported lipid bilayers that are expanding

A key result: adherent cells maintain long-range membrane tension gradients even when they are not migrating! (micropatterned cells below) In contrast, non-adherent migrating cells *do not* show these gradients.

Microfluidic pumping with active nematics! Self-organized and self-sustained. No external pumps. @pnas.org @ub.edu www.pnas.org/doi/10.1073/... #ActiveMatter #Microfluidics #SoftMatter

Maria Tettamanti shows that inhibition of TORC2 by the small amphipath PalmC induces the TORC2-dependent internalization of sterols. Congrats to Maria and all coworkers involved, and to EMBOj for the efficient review process: use review commons! @biology-unige.bsky.social @sciencesunige.bsky.social

Etienne @membramics-lab.bsky.social is very happy to visit @rouxlab.bsky.social in Geneva! great people, great projects, good memories...

‪ Congratulations @centriolelab.bsky.social @dudinlab.bsky.social and @gautamdey.bsky.social for your publication in @cp-cell.bsky.social: Charting the landscape of #cytoskeletal diversity in #microbial eukaryotes #Expansion #Microscopy @sciencesunige.bsky.social www.unige.ch/medias/en/20...

*ALL*source data and Python notebooks are available (you can reproduce all figures!) 🔗 doi.org/10.6084/m9.f... We hope this helps make lifetime analysis transparent and comparable across setups. 📄 www.biorxiv.org/content/10.1... @rouxlab.bsky.social #FLIM #FlipperTR #Microscopy #OpenScience

🚨 New preprint out! “Fluorescence lifetime estimation: a practical approach using Flipper-TR FLIM” with Tithi Mandal and @rouxlab.bsky.social We benchmark and describe step-by-step Flipper-TR FLIM measurements across different set-ups and and strategies. www.biorxiv.org/content/10.1...

I am pleased to 📣 today’s superb thesis defense by Christian Schroer on “Chemical strategies for studying lipid signaling and transport”. Part of his work was recently published in the JLR; the other part will follow soon. A very proud and somewhat tipsy “Doktorvater” 🥂

Undergraduate/internship/master's thesis position: jobs.helsinki.fi/job-invite/4...

PhD student position: jobs.helsinki.fi/job-invite/4...

I have a PhD student and an undergrad student positions open at the Institute of Biotechnology @helsinki.fi We are using reconstitution, cell and structural biology to study protein-membrane interactions and membrane microdomain formation. Links to calls below! Feel free to drop a message and share!

"Impaired hematopoiesis and embryonic lethality at midgestation of mice lacking both lipid transfer proteins VPS13A and VPS13C" out now in PLOS Biology journals.plos.org/plosbiology/...

Order matters! Aurelien Roux @rouxlab.bsky.social studied the formation of multi-cellular tornado-like structures and regeneration of heads in hydra to share with us how stress fields, topology and geometry of initial tissue organization set the sequence of morphogenesis. #MBIMPG2025

Previous preprint is now published in RSC Chemical Biology. If you are interested in plasma membrane labeling, see the paper! 👇 pubs.rsc.org/en/content/a...

Nice discussions after the talk given online yesterday at cytophys.org, presenting the work of @pauguillamat.bsky.social @clairedessalles.bsky.social @yamini-ravichan.bsky.social @oriolmb.bsky.social and Tithi Mandal. Available on the lab youtube channel at: youtu.be/g-7HomnPdtk

Ever wished to become an actin star? 😎 Then try getting suspended above a non-adhesive substrate. www.nature.com/articles/s41...

Hello microscopy and imaging experts and enthusiasts! We are looking for a staff scientist to join us here in Geneva to work on microscopy and image analysis projects! See the link for the job announcement (in French and in English). Please apply and/or repost! jobs.unige.ch/www/wd_porta...

The @embo.org ESCRT meeting was packed with membrane remodeling from every branch of the tree of life🌳. Some awesome science 🧪 highlights in the next posts 🧵. But a first impression… the venue!! Wow, Caux castle up a cogwheel train, overlooking Lac Léman! Perfect! 🌄 Thank you @rouxlab.bsky.social 🤗