Mara Mueller

Link to open access version: pure.mpg.de/view/item_36...

Even more hibernating dimers out there!

A new preprint by @qiangguo.bsky.social shows oligomerization of inactive ribosomes is a mechanism shared across different expansion segments and stress conditions.

Ribosomal RNA expansion segments mediate the oligomerization of inactive animal ribosomes Cells down-regulate protein synthesis when stressed to conserve energy and shift resources toward repair. We found that in some mammalian cells, including neurons, stress also resulted in the formatio...

Out now in @science.org
Ribosomal RNA expansion segments mediate the oligomerization of inactive animal ribosomes | Science www.science.org/doi/10.1126/...

Thank you 🤗

Thank you 🤗

Thank you 🤗

Thank you!
Would love to :)

Ribosomes in pairs: A survival strategy inside stressed cells.
When nutrients drop or temperatures shift, cells switch to survival mode. New work by @erin-schuman.bsky.social & colleagues shows that inactive ribosomes pair up via a ribosomal RNA link @andschwarz.bsky.social @muellermara.bsky.social

Interestingly, chickens use a similar interaction to form tetramers (ES9L connecting to ES31L) upon stress. Could expansion segment mediated oligomerization be a commonly used mechanism to store-away inactive ribosomes across animals? 🧵 6/6

This dimerization can be predicted from the primary sequence of ES31Lb across species and is predicted to occur in 17% of chordates (black marks), including one of the rRNA variants in humans 🧵 5/6

Somehow this disome formation is beneficial to cells. Clones overexpressing a hairpin that outcompetes disome formation (A) are more sensitive to long-term stress (B) and show stunted growth (C) 🧵 4/6

ES31Lb is both necessary and sufficient for disome formation, as it can outcompete the interaction in rat cell lysates (A) and induce disomes in bakers yeast, an organism that does not naturally form dimers (B) 🧵 3/6

Cryo-ET of primary rat neurons shows that these disomes are translationally inactive and seem to be interacting via a part of the ribosomal RNA, expansion segment 31 - helix b (ES31Lb) via a kissing-loop interaction 🧵 2/6

In rats many different stressors induce not only a reduction in polysomes and an increase in monosomes, but surprisingly also a stark increse in disomes 🧵 1/6

Mammalian cells form hibernating disomes akin to those in bacterial cells - but connected via ribosomal RNA

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

co-first with: @andschwarz.bsky.social

with: @lea-dietrich.bsky.social, @sgiando.bsky.social, @erin-schuman.bsky.social and many more

🧵 0/6
#MolBio 🧪

I’m excited to share my PhD work on localized mRNAs and protein synthesis in cortical layer 1 on bioRxiv! www.biorxiv.org/content/10.1...

Check out our new preprint on an integrated pipeline combining in situ #cryo-ET with MALDI #MSImaging for single-cell identification and classification from previously analysed EM-grids.
Link: www.biorxiv.org/content/10.1...

In mESCs autophagy prevents POMP accumulation and nucleolar localization (F). This mechanism is developmentally regulated and lost with differentiation (G). Additionally, POMP nuclear relocalization is observed in a mouse model of Huntington’s disease (H). 🧵4/4

Upon relocalization POMP acquires a new set of interaction partners (D), preserves ribogenesis (E) and drives a protective transcriptional program (F) 🧵3/4

Normally POMP is rapidly degraded during protesome biogenesis (A), but in response to stress it accumulates without a concomitant increase in partner proteasome subunits (B) This stoichiometric uncoupling together with increased ROS leads to its relocalization to the nucleolus (C) 🧵2/4

New Preprint out !

The proteasome maturation factor POMP moonlights as a stress-induced transcriptional regulator
www.biorxiv.org/content/10.1...

Lead by: @sgiando.bsky.social
with: @muellermara.bsky.social , @erin-schuman.bsky.social , @marcvoo.bsky.social and many more

Short thread below 🧵1/4

Normally POMP is rapidly degraded during protesome biogenesis (A), but in response to stress it accumulates without a concomitant increase in partner proteasome subunits (B) This stoichiometric uncoupling together with increased ROS leads to its relocalisation to the nucleolus (C) 🧵2/4

Gilles Laurent is awarded the Louis-Jeantet Prize for Medicine in 2025 The 2025 Louis-Jeantet Prizes are awarded to Gilles Laurent, director at the Max Planck Institute for Brain Research in Frankfurt and to Veit Hornung, professor at the Ludwig Maximilian University of ...

Congratulations to @mpibrain.bsky.social director Gilles Laurent for being awarded the 2025 Louis-Jeantet prize for Medicine! The @louisjeantetfdn.bsky.social recognizes Laurent's pioneering work on the operations of #neurons and dynamics of neuronal networks. More infos 👉 bit.ly/4hqk6ie

Understanding the molecular diversity of synapses - Nature Reviews Neuroscience The set of proteins present at synapses determines their heterogeneous functions and properties. In this Review, van Oostrum and Schuman describe the molecular mechanisms that contribute to the d...

"Understanding the molecular diversity of synapses" new review by my boss @erin-schuman.bsky.social and former postdoc @marcvoo.bsky.social out now in Nature Reviews Neuroscience:

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

Seconding @dpastoors.bsky.social recommendation: I use eLabFTW every day and love it. Open-source, freeware, completely customizable and lets you host everything on your own servers
www.elabftw.net