Karousis Lab

Using "in extracto cryo-EM", we visualize ribosomes in mammalian lysates, including RRL. "Hibernating" ribosomes carry an extended set of proteins that protect functional centers. These include elongation factor eEF2, LARP1 implicated in mTOR signaling, eIF5A etc. www.biorxiv.org/content/10.1...

ZAK activation at the collided ribosome - Nature The kinase ZAK is activated at collided ribosomes to mediate the ribotoxic stress response.

Check out our latest work on how collided ribosomes activate the MAP3K ZAK! 💫

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

A fun collaboration with @beckmannlab.bsky.social @doubleshuang.bsky.social

A human cell-free translation screen identifies the NT-2 mycotoxin as a ribosomal peptidyl transferase inhibitor Translation inhibitors are invaluable for probing ribosome function and therapeutic applications, but systematic discovery in human systems is limited by the lack of scalable, screening-compatible cel...

Great work! It fits with our observations of a mycotoxin engaging ribosomes with SERBP1, apparently in a similar dormant state to the one that you observed. www.biorxiv.org/content/10.1...

Exciting new #Zebrafish research from the #WeinsteinLab, led by Jong Park!
“Specialized gas-exchange endothelium of the zebrafish gill” —

www.biorxiv.org/content/10.6...

Amazing to see red blood cells moving through the gills! Don’t forget to check out the supplemental movies ;-)

Before a job interview 😅

First time it happened to my lecture I thought it's an earthquake (Greek in Switzerland)

#RNASky #BiologySky #CryoEM

This work was possible thanks with the Cryo-EM hub at the @ethz.ch and the BSF screening facility at the EPFL.
@nccr-rna-disease.bsky.social @mcid-unibe.bsky.social

🧬 NT-2 binds at 60S PTC where peptide bonds form and stabilizes an inactive SERBP1-bound state only when living cells are treated,
establishing a direct structural link between a small-molecule inhibitor and ribosome dormancy.
#translation #cryoEM #biochemistry

💡 We built a quantitative human-based cell-free translation platform that tests thousands of reactions in parallel, directly measuring protein synthesis while bypassing cellular toxicity.

#quantitativebiology #RNA #ribosome #cellfree #drugdiscovery

A human cell-free translation screen identifies the NT-2 mycotoxin as a ribosomal peptidyl transferase inhibitor Translation inhibitors are invaluable for probing ribosome function and therapeutic applications, but systematic discovery in human systems is limited by the lack of scalable, screening-compatible cel...

🚀 New preprint!
We used a human cell-free translation screen (~28 000 compounds) to discover NT-2, a #Fusarium -derived #mycotoxin that blocks human ribosomes.
#Cryo-EM at 1.72 Å reveals a link between chemical inhibition and ribosome dormancy.
www.biorxiv.org/content/10.1...

It was a joy hosting @mandymuller.bsky.social in Bern!

Nature Reviews Methods Primers (2025): "Flow biocatalysis"

https://paradisiresearch.com/research-highlights/nature-reviews-methods-primers-2025-flow-biocatalysis/

Very exciting and nicely illustrated! Congratulations!

Polysomes and mRNA control the biophysical properties of the eukaryotic cytoplasm Gade et al. report that polysomes and mRNA levels impact the biophysical properties of the cytoplasm. Using passive rheology probes and single-particle tracking, they demonstrate that intracellular diffusion is enhanced when polysomes are disassembled or when mRNA levels are reduced in eukaryotic cells.

Polysomes and mRNA control the biophysical properties of the eukaryotic cytoplasm

Protocol for monitoring mRNA translation and degradation in human cell-free lysates Cell-free translation is a powerful tool for studying protein synthesis. Here, we present a protocol for monitoring mRNA translation and degradation u…

*️⃣ Step-by-step STAR protocol for Cell-free translation and mRNA decay *️⃣
What to do (and what not to do 😅) guide based on our work on Nsp1 published in @cp-cellreports.bsky.social.
www.sciencedirect.com/science/arti...
@unibe.ch @mcid-unibe.bsky.social @nccr-rna-disease.bsky.social @snf-fns.ch

Excellent science, impeccable organisation and breathtaking views in and out the #RNA turnover #BiochemEvent in Brighton, UK 🌊🧬 @biochemsoc.bsky.social

Predicting the translation efficiency of messenger RNA in mammalian cells Nature Biotechnology - A deep convolutional neural network model predicts the influence of the full-length mRNA sequence on translation efficiency.

Very excited that our most significant work, a collaboration w/ Dr. Can Cenik at UT Austin on translational gene regulation, was finally published in Nature Biotechnology in a dual set of studies:

Paper 1 -- an AI model trained to predict translation rates from mRNA sequences: rdcu.be/exN1l

Translation efficiency covariation identifies conserved coordination patterns across cell types - Nature Biotechnology Matched ribosome profiling and RNA sequencing data quantify translation efficiency patterns across 140 human and mouse cell lines.

Translation efficiency covariation identifies conserved coordination patterns across cell types go.nature.com/3TXvmZy

🌊 Potential lab logo 🌊

New paper out in Mol Cell, where we show how N-myristolytransferases lipidate proteins on the translating ribosome!
Continuing our successful collaboration with DeuerlingLab @uni-konstanz.de & Shu-ou Chan @caltech.edu
@snsf.ch @ethz.ch
www.cell.com/molecular-ce...

Intracellular pathogen effector reprograms host gene expression by inhibiting mRNA decay - Nature Communications Intracellular pathogens hijack host gene expression to subvert cellular processes. Here, the authors show that Legionella pneumophila’s PieF effector inhibits the human CCR4-NOT deadenylation machiner...

Happy to share the latest work on a bacterial protein that inhibits human mRNA decay machinery, in collaboration with @smlea.bsky.social #RNAsky

www.nature.com/articles/s41... Intracellular pathogen effector reprograms host gene expression by inhibiting mRNA decay | Nature Communications

What if I told you, there is a way to pause the time?

Great read from Akis and colleagues! @akispapantonis.bsky.social

Helicobacter pylori CagA protein is a potent and broad-spectrum amyloid inhibitor Helicobacter pylori CagA protein strongly inhibits functional and pathogenic amyloid fibril formation in both bacteria and humans.

A protein produced by the pathogenic bacteria Helicobacter pylori can block amyloid proteins from clustering, new #ScienceAdvances research finds.

Our method paper to produce efficient cell-free translation lysates from diverse human cell types is out 🎉 www.jbc.org/article/S002... @unibe.ch @mcid-unibe.bsky.social
@muehlemann.bsky.social @nickkouvelas.bsky.social

Thanks a lot, Jonathan!

Winning the lecturer of the year award from the #Biology department of @unibe.ch definitely made my day 🤩🎉 (after a tough week, otherwise 😅). UniBern has been very supportive and generous in providing excellent teaching courses so KUDOS to them!

I am very excited and grateful for the opportunity to present our work and exchange ideas with the research community at LMU Munich hosted by Jonathan Bohlen! @jonathanbohlen.bsky.social @jonathanbohlen.bsky.social @unibe.ch @mcid-unibe.bsky.social @nccr-rna-disease.bsky.social

Lessons on how to breathe 🌳🇨🇭
#Biochemistry #academicteaching @unibe.ch