Ahmad Jomaa

Congrats, Kelly! A very well deserved recognition.

Recruitment of bifunctional regulator thermospermine to methylated ribosomes directs xylem fate Polyamines are often associated with ribosomes and are thought to stabilize their integrity. In Arabidopsis, the polyamine thermospermine (tSpm) affects xylem cell fate. tSpm induces translation of SU...

In @science.org this week, thermospermine affects ribosome methylation, which in turn regulates translation of xylem development proteins www.science.org/doi/10.1126/...

#plantscience

Mechanisms linking cytoplasmic decay of translation-defective mRNA to transcriptional adaptation Transcriptional adaptation (TA) is a genetic robustness mechanism through which mutant messenger RNA (mRNA) decay induces sequence-dependent up-regulation of so-called adapting genes. How cytoplasmica...

Ever notice that when one gene is disrupted, its orthologs get upregulated? This phenomenon, known as transcriptional adaptation, has been controversial and mysterious - glad to see that we are starting to learn how it works.

very cool, Florent! Congrats! What do you think the additional part in the back does?

Long in the making, but happy to present the Chlamydomonas chlororibosome!
Cryo-ET🔬reveals a large new domain on the small subunit, built from multiple extensions in conserved ribosomal proteins.
bioRxiv 📖: shorturl.at/q44tG
This suggests greater chlororibosome diversity than expected!
1/n 🧵

Caveolins are conserved (metazoan) proteins essential for forming membrane-derived vesicles called caveolae.

While evolutionarily distant caveolins have similar structures, we found they do not maintain caveolae-generating capabilities (movie).

What determines this? Check out our new preprint!

Yeast elongation factor homolog New1 protects a subset of mRNAs from degradation by no-go decay Abstract. New1 is a homologue of the essential yeast translation elongation factor eEF3. Lack of New1 has been shown to induce ribosome queuing upstream of

4 - Still lots to learn about this mysterious factor.
🔗 Read the paper: academic.oup.com/nar/article/...
Funded by @dfg.de via SFB TRR319-RMaP 🙏
#RibosomeBiology #TranslationQC #RNA #Nanopore #Yeast #PhDPosition #DFG #RMaP #New1

I finally got to read this today, very nice work and amazing that you can capture such transient interaction! Congrats David and co.

New work from our Haselbach lab with collaborators captures ribosomes 𝘮𝘪𝘥-𝘣𝘶𝘪𝘭𝘥 and reveals a flexible, modular strategy behind their assembly, rather than a strict assembly line.
Published in _Nucleic Acids Research _👉 https://doi.org/10.1093/nar/gkag036

Structures of naked mole-rat, tuco-tuco, and guinea pig ribosomes—is rRNA fragmentation linked to translational fidelity? Abstract. Ribosomes are central to protein synthesis in all organisms. In mammals, the ribosome functional core is highly conserved. Remarkably, two rodent

now online:
academic.oup.com/nar/article/...

thanks, Mimi. Let's catch up soon!

super cool! Congrats!

ADAM-tRNA-seq: an optimized approach for demultiplexing and enhanced hierarchal mapping in direct tRNA sequencing Abstract. Transfer RNAs (tRNAs) play an essential role in protein synthesis and cellular homeostasis, and their dysregulation is associated with various hu

Interested in direct tRNA-seq by Nanopore? We developed a new RNA-based barcoding aproach for seq parallelization; it is also cost-saving. Scripts available on github. #tRNA #Nanopore

track.smtpsendmail.com/9032119/c?p=...

Thanks CJ!

thanks so much, Zoya! I hope all is well.

Our paper on the structural and functional basis of the human dimeric OS9–SEL1L–HRD1 ERAD complex, together with @qilabuva.bsky.social, is now out! Huge congratulations to Leo, Emir, and Elina!
www.nature.com/articles/s41...

Complexity at the ribosomal polypeptide tunnel exit. The major N-terminal acetyltransferase NatA may form different complexes on the ribosome to facilitate protein maturation. By Marius Klein & Klemens Wild in Irmgard Sinning's lab BZH & Nina McTiernan in my lab. www.nature.com/articles/s41...

ER exit sites mediated by the COPII adaptor sec24D selectively recruit lipid raft-preferring proteins for rapid ER export Nature Communications - Through synchronized cargo traffic experiments, the authors explore the role of raft partitioning in ER efflux. Raft-preferring cargos show specific preferences for ER exit...

Excited to share a new story that transformed how we think about membrane domains in the ER!

rdcu.be/eR7Cn

ER exit sites mediated by the COPII adaptor sec24D selectively recruit lipid raft-preferencing proteins for rapid ER export

Wondering what’s so new and exciting? Skytorial below!

1/9

Super cool!

We’re excited to share our latest preprint on the mechanism of excised linear intron stabilization in yeast! This work was led by PhD student @glennli.bsky.social and was a wonderful collaboration with @maxewilkinson.bsky.social. Link: www.biorxiv.org/content/10.6... (1/4)

Oh wow! Dawid, congrats! I was very to happy to read this post this morning.

We’re thrilled to share our latest iTP-seq protocol for mapping bacterial translation landscapes in vitro — with a complete experimental workflow streamlined by Mélanie Gillard and an open source Python library for data analysis developed by Thibaud Renault.

Mitochondrial presequences harbor variable strengths to maintain organellar function. New study from Youmian Yan, Natalie Niemi (@nieminm.bsky.social) et al. @washumedicine.bsky.social: rupress.org/jcb/article/...

@ianofbristol.bsky.social
#Biochemistry #CellMetabolism #Organelles #Mitochondria

Discovery and development of a new oxazolidinone with reduced toxicity for the treatment of tuberculosis @naturemedicine.bsky.social
www.nature.com/articles/s41...

Energy-landscape model of RF2 activation. Comparison of termination complexes (TC), wild-type ArfA-bound nonstop elongation complexes (nsECs), and loss-of-function ArfA mutant-bound nsECs reveals that wild-type ArfA promotes RF2 docking to nsECs by reshaping the conformational cascade.

Slightly overdue article highlight!

In PNAS, we use smFRET to reveal how polypeptide release factor 2 (RF2) undergoes a cascade of structural changes to catalyze polypeptide release during translation termination and ArfA-mediated ribosome rescue.

🧵⬇️
doi.org/10.1073/pnas...

Mechanistic model for +1 frameshifting suppression. The m¹G37 tRNA modification blocks expanded codon–anticodon interactions, preserving translational fidelity.

A (belated!) highlight from an excellent collaboration with
@dunhamlab.bsky.social and #HouLabTJU.

In this Nat Commun paper, we combine smFRET and cryo-EM to show how the tRNA modification m¹G37 stabilizes the reading frame—and what happens when it’s missing.

Mechanical forces regulate the composition and fate of stalled nascent chains Khan et al. show that mechanical forces on stalled nascent polypeptide chains (NCs) regulate the amino acid composition of carboxyl-terminal tails (CAT tails), which are a form of NC elongation that occurs without an mRNA. Two distinct modes of CAT tailing facilitate on-ribosome ubiquitination of NCs (“extrusion mode”) and their release from ribosomes (“release mode”), protecting cells from the consequences of clogged ribosomal subunits and aggregation-prone NCs.

Online Now: Mechanical forces regulate the composition and fate of stalled nascent chains Online now:

Missing steps of mitochondrial translation initiation identified in plants www.biorxiv.org/content/10.64898/2025.12.30.697032v1 #cryoEM

Evolution of the ribosomal exit tunnel through the eyes of the nascent chain The ribosomal exit tunnel is a universally conserved feature of the large subunit that directs the nascent polypeptide chain into the cellular environment and is involved in co-translational folding, ...

Just in time for 2026! 🎆 Presenting a nascent-centric view on the shape of the ribosomal exit tunnel topology, based on MD-derived occupancy maps for 55 distinct ribosomes. 🧶🧬🖥️
📄 Read the preprint: biorxiv.org/content/10.6...

#StructuralBiology #Ribosome #CryoEM #Evolution #Biophysics

The sporulation phosphorelay protein Spo0B is membrane localized in Paenibacillus! The transmembrane domain appears to increase interaction with relay partners. Congrats to former lab undergrad @isabellalin.bsky.social and her grad mentor @cassidyprints.bsky.social

journals.asm.org/doi/10.1128/...