Florent Waltz
@florentwaltz.bsky.social
SNSF Ambizione Project Leader
Looking at tiny frozen mitochondria with big microscopes 🔬 cryoEM/cryoET
Green organisms 🌿 & evolution 🦠
Biozentrum, hosted in the Engel Lab, CH
🇫🇷 -> 🇩🇪 -> 🇨🇭
Website: https://www.waltzresearch.com/
Looking at tiny frozen mitochondria with big microscopes 🔬 cryoEM/cryoET
Green organisms 🌿 & evolution 🦠
Biozentrum, hosted in the Engel Lab, CH
🇫🇷 -> 🇩🇪 -> 🇨🇭
Website: https://www.waltzresearch.com/
Pinned
Florent Waltz
@florentwaltz.bsky.social
· Mar 20
In a new Science study, cryo–electron tomography captures the in-cell architecture of the mitochondrial respiratory chain, illuminating how the coordinated action of molecular machines drives life’s fundamental energy conversion.
Learn more in this week's issue: scim.ag/3FA3Ygq
Learn more in this week's issue: scim.ag/3FA3Ygq
The final version of our work on the in-cell architecture of the mitochondrial respiratory chain is now online in @science.org 🎉
You can find the full story here www.science.org/doi/10.1126/...
@verenaresch.bsky.social did a wonderful job on the cover and animation, she really brought it to life 👩🎨
You can find the full story here www.science.org/doi/10.1126/...
@verenaresch.bsky.social did a wonderful job on the cover and animation, she really brought it to life 👩🎨
Yeah super cool! Look at these beautiful cells, tons of eukaryotes 🦠 images using expansion microscopy 🔬
What's next? Expand the world 🌎 ?!
Congrats !
What's next? Expand the world 🌎 ?!
Congrats !
🚨Our collaboration with @centriolelab.bsky.social & @gautamdey.bsky.social is out today in @cp-cell.bsky.social
We show that #Expansion #Microscopy is a broad-spectrum modality for Euks, enabling 3D phenotypic maps rooted to phylogeny.
#ProtistsOnSky #SciComm #SciSky
www.cell.com/cell/fulltex...
We show that #Expansion #Microscopy is a broad-spectrum modality for Euks, enabling 3D phenotypic maps rooted to phylogeny.
#ProtistsOnSky #SciComm #SciSky
www.cell.com/cell/fulltex...
November 1, 2025 at 11:02 AM
Yeah super cool! Look at these beautiful cells, tons of eukaryotes 🦠 images using expansion microscopy 🔬
What's next? Expand the world 🌎 ?!
Congrats !
What's next? Expand the world 🌎 ?!
Congrats !
Reposted by Florent Waltz
We’re back with the next DinoSphere Online Seminar!
Join us on Nov 4th, we're hosting:
Edmée Royen (ULiège) - Symbiodinium
Nicolas dos Santos Pacheco (Cambridge) - Perkinsids
📅 Tue, Nov 4 - 4 PM CET/3 PM GMT
💻 Zoom link: sites.google.com/view/dinosphere
Please spread the word!
#protistonsky
Join us on Nov 4th, we're hosting:
Edmée Royen (ULiège) - Symbiodinium
Nicolas dos Santos Pacheco (Cambridge) - Perkinsids
📅 Tue, Nov 4 - 4 PM CET/3 PM GMT
💻 Zoom link: sites.google.com/view/dinosphere
Please spread the word!
#protistonsky
October 28, 2025 at 3:29 PM
We’re back with the next DinoSphere Online Seminar!
Join us on Nov 4th, we're hosting:
Edmée Royen (ULiège) - Symbiodinium
Nicolas dos Santos Pacheco (Cambridge) - Perkinsids
📅 Tue, Nov 4 - 4 PM CET/3 PM GMT
💻 Zoom link: sites.google.com/view/dinosphere
Please spread the word!
#protistonsky
Join us on Nov 4th, we're hosting:
Edmée Royen (ULiège) - Symbiodinium
Nicolas dos Santos Pacheco (Cambridge) - Perkinsids
📅 Tue, Nov 4 - 4 PM CET/3 PM GMT
💻 Zoom link: sites.google.com/view/dinosphere
Please spread the word!
#protistonsky
Last Friday (17th), we had an amazing first Young Swiss Tomo meeting in Bern, organized with Elda Bauda, Zanetta Kechagia, and @leonieanton.bsky.social!
Over 70 people from 🇨🇭 gathered to talk about cryo-electron tomography 🔬.
Huge thanks to the DCI for making the event possible! See you next year! 👋
Over 70 people from 🇨🇭 gathered to talk about cryo-electron tomography 🔬.
Huge thanks to the DCI for making the event possible! See you next year! 👋
October 19, 2025 at 9:16 AM
Last Friday (17th), we had an amazing first Young Swiss Tomo meeting in Bern, organized with Elda Bauda, Zanetta Kechagia, and @leonieanton.bsky.social!
Over 70 people from 🇨🇭 gathered to talk about cryo-electron tomography 🔬.
Huge thanks to the DCI for making the event possible! See you next year! 👋
Over 70 people from 🇨🇭 gathered to talk about cryo-electron tomography 🔬.
Huge thanks to the DCI for making the event possible! See you next year! 👋
Reposted by Florent Waltz
✨Excited that the main project of my PhD is now available as a pre-print on #bioRxiv
Here, we used #CryoET to visualise mitochondrial proteostatic stress and together with SPA #CryoEM shed light into the functional cycle of the Hsp60:10 chaperone system. #TeamTomo
🔗 www.biorxiv.org/content/10.1...
Here, we used #CryoET to visualise mitochondrial proteostatic stress and together with SPA #CryoEM shed light into the functional cycle of the Hsp60:10 chaperone system. #TeamTomo
🔗 www.biorxiv.org/content/10.1...
October 8, 2025 at 3:59 PM
✨Excited that the main project of my PhD is now available as a pre-print on #bioRxiv
Here, we used #CryoET to visualise mitochondrial proteostatic stress and together with SPA #CryoEM shed light into the functional cycle of the Hsp60:10 chaperone system. #TeamTomo
🔗 www.biorxiv.org/content/10.1...
Here, we used #CryoET to visualise mitochondrial proteostatic stress and together with SPA #CryoEM shed light into the functional cycle of the Hsp60:10 chaperone system. #TeamTomo
🔗 www.biorxiv.org/content/10.1...
Check this out! The mysterious widespread CAGE protein complex found by my colleague @computingcaitie.bsky.social ! Cool stuff there 🥨
Shows you how much we still can and have to discover !
Shows you how much we still can and have to discover !
I am excited to share our new preprint on the CAGE complex, a mysterious hollow protein complex that I first saw years ago while surveying Tetrahymena ciliary lysate www.biorxiv.org/content/10.1... #cilia #protistsonsky 🧬🧪
September 25, 2025 at 6:23 AM
Check this out! The mysterious widespread CAGE protein complex found by my colleague @computingcaitie.bsky.social ! Cool stuff there 🥨
Shows you how much we still can and have to discover !
Shows you how much we still can and have to discover !
I had a wonderful time in Japan 🗼! Huge thanks to @ken-wakaba.bsky.social for inviting me to Sangyo University in Kyoto. Thanks to Takashi Yamano (and Ken-ichi) for organizing the Beyond the Green 🍀 session at the Japanese Botanical Society meeting!
Great science and discussions!
Great science and discussions!
September 22, 2025 at 2:59 AM
I had a wonderful time in Japan 🗼! Huge thanks to @ken-wakaba.bsky.social for inviting me to Sangyo University in Kyoto. Thanks to Takashi Yamano (and Ken-ichi) for organizing the Beyond the Green 🍀 session at the Japanese Botanical Society meeting!
Great science and discussions!
Great science and discussions!
Mitochondria finally made the headlines, yay!
Oh wait, ... oh no ....
Oh wait, ... oh no ....
via @acyn.bsky.social
RFK JR: I’m looking at kids as I walk through the airports today...and I see these kids that are just overburdened with mitochondrial challenges, inflammation—you can tell from their faces, movements, and lack of social connection
RFK JR: I’m looking at kids as I walk through the airports today...and I see these kids that are just overburdened with mitochondrial challenges, inflammation—you can tell from their faces, movements, and lack of social connection
August 28, 2025 at 3:43 PM
Mitochondria finally made the headlines, yay!
Oh wait, ... oh no ....
Oh wait, ... oh no ....
Reposted by Florent Waltz
Our #CryoET story on how a top antimalarial drug candidate perturbs the native malarial translation machinery is out @natsmb.nature.com🥳 rdcu.be/eBbrH
A massive team effort led by @leonieanton.bsky.social Meseret Haile & Wenjing Cheng in collaboration with Jerzy Dziekan & the Alan Cowman! #TeamTomo
A massive team effort led by @leonieanton.bsky.social Meseret Haile & Wenjing Cheng in collaboration with Jerzy Dziekan & the Alan Cowman! #TeamTomo
Integrated structural biology of the native malarial translation machinery and its inhibition by an antimalarial drug
Nature Structural & Molecular Biology - Integrated structural biology approach leveraging in situ cryo-electron tomography reveals molecular details of the native malarial translation...
rdcu.be
August 18, 2025 at 12:13 PM
Our #CryoET story on how a top antimalarial drug candidate perturbs the native malarial translation machinery is out @natsmb.nature.com🥳 rdcu.be/eBbrH
A massive team effort led by @leonieanton.bsky.social Meseret Haile & Wenjing Cheng in collaboration with Jerzy Dziekan & the Alan Cowman! #TeamTomo
A massive team effort led by @leonieanton.bsky.social Meseret Haile & Wenjing Cheng in collaboration with Jerzy Dziekan & the Alan Cowman! #TeamTomo
Very cool! How do cytosolic ribosomes discriminate between ER and mitochondria targeted proteins?
NAC recognizes mitochondrial targeting sequences! Very important since over 95% of the mitochondrial proteome is translated in the cytosol and then imported to mitochondria.
Congrats!
NAC recognizes mitochondrial targeting sequences! Very important since over 95% of the mitochondrial proteome is translated in the cytosol and then imported to mitochondria.
Congrats!
Check out our new preprint on the discovery of a molecular switch in NAC that mediates nascent chain sorting on the ribosome and prevents mitochondrial protein mistargeting by SRP. A great collaboration with the Shan Lab @Caltech and the Qi Lab @UVA: www.biorxiv.org/content/10.1...
August 2, 2025 at 1:27 PM
Very cool! How do cytosolic ribosomes discriminate between ER and mitochondria targeted proteins?
NAC recognizes mitochondrial targeting sequences! Very important since over 95% of the mitochondrial proteome is translated in the cytosol and then imported to mitochondria.
Congrats!
NAC recognizes mitochondrial targeting sequences! Very important since over 95% of the mitochondrial proteome is translated in the cytosol and then imported to mitochondria.
Congrats!
A step towards easier control over mitochondrial gene expression:
Silencing mitochondrial gene expression in living cells | Science www.science.org/doi/10.1126/...
Silencing mitochondrial gene expression in living cells | Science www.science.org/doi/10.1126/...
Silencing mitochondrial gene expression in living cells
Mitochondria fulfill central functions in metabolism and energy supply. They express their own genome, which encodes key subunits of the oxidative phosphorylation system. However, the central mechanis...
www.science.org
July 31, 2025 at 6:19 PM
A step towards easier control over mitochondrial gene expression:
Silencing mitochondrial gene expression in living cells | Science www.science.org/doi/10.1126/...
Silencing mitochondrial gene expression in living cells | Science www.science.org/doi/10.1126/...
Cell-to-cell connections in plants 🌿!
Using cryo-ET 🔬 to have a look at plasmodesmata.
Congrats Marcel, Matthias and co!
You managed to push it far beyond what I thought was possible !
Using cryo-ET 🔬 to have a look at plasmodesmata.
Congrats Marcel, Matthias and co!
You managed to push it far beyond what I thought was possible !
New preprint: In situ Architecture of #Plasmodesmata.
Using #cryoET, #AlphaFold & proteomics, we uncover the native organization of plant intercellular nanopores.
🔗 doi.org/10.1101/2025...
🧪🧵1/n
#teamtomo #PlantScience #Physcomitrium #Arabidopsis #cryoEM
Using #cryoET, #AlphaFold & proteomics, we uncover the native organization of plant intercellular nanopores.
🔗 doi.org/10.1101/2025...
🧪🧵1/n
#teamtomo #PlantScience #Physcomitrium #Arabidopsis #cryoEM
July 27, 2025 at 9:17 PM
Cell-to-cell connections in plants 🌿!
Using cryo-ET 🔬 to have a look at plasmodesmata.
Congrats Marcel, Matthias and co!
You managed to push it far beyond what I thought was possible !
Using cryo-ET 🔬 to have a look at plasmodesmata.
Congrats Marcel, Matthias and co!
You managed to push it far beyond what I thought was possible !
Reposted by Florent Waltz
New preprint: In situ Architecture of #Plasmodesmata.
Using #cryoET, #AlphaFold & proteomics, we uncover the native organization of plant intercellular nanopores.
🔗 doi.org/10.1101/2025...
🧪🧵1/n
#teamtomo #PlantScience #Physcomitrium #Arabidopsis #cryoEM
Using #cryoET, #AlphaFold & proteomics, we uncover the native organization of plant intercellular nanopores.
🔗 doi.org/10.1101/2025...
🧪🧵1/n
#teamtomo #PlantScience #Physcomitrium #Arabidopsis #cryoEM
July 26, 2025 at 3:38 PM
New preprint: In situ Architecture of #Plasmodesmata.
Using #cryoET, #AlphaFold & proteomics, we uncover the native organization of plant intercellular nanopores.
🔗 doi.org/10.1101/2025...
🧪🧵1/n
#teamtomo #PlantScience #Physcomitrium #Arabidopsis #cryoEM
Using #cryoET, #AlphaFold & proteomics, we uncover the native organization of plant intercellular nanopores.
🔗 doi.org/10.1101/2025...
🧪🧵1/n
#teamtomo #PlantScience #Physcomitrium #Arabidopsis #cryoEM
Cool paper from cool people 😎
Expand all the things!
Expand all the things!
Excited to share the lab's 1rst preprint! Rapid high-res immunofluorescence is now possible in cultured & environmental diatoms thanks to 4-fold expansion microscopy. A step-change for comparative cell biology in one of the most important phytoplankton groups on the planet 🥳
tinyurl.com/m9s5su7s 1/2
tinyurl.com/m9s5su7s 1/2
June 17, 2025 at 7:40 AM
Cool paper from cool people 😎
Expand all the things!
Expand all the things!
Curious about dinoflagellates? Tiny water bugs with super cool cellular architecture?
Check out this cool initiative from my colleague @manondemulder.bsky.social and her friends!
Their 1st online seminar is next month, don't miss it!
Check out this cool initiative from my colleague @manondemulder.bsky.social and her friends!
Their 1st online seminar is next month, don't miss it!
We’re kicking off the DinoSphere Online Seminar Series! Join us for our first session with Karel Mockaer (Heidelberg) & Yong Heng Phua (OIST)
📅 1 July 9AM CEST
🔗 tinyurl.com/4mjaverj
Spread the word!
@protistwtmostest.bsky.social @ehehenberger.bsky.social @chandnibhickta.bsky.social&Norico Yamada
📅 1 July 9AM CEST
🔗 tinyurl.com/4mjaverj
Spread the word!
@protistwtmostest.bsky.social @ehehenberger.bsky.social @chandnibhickta.bsky.social&Norico Yamada
June 4, 2025 at 4:32 PM
Curious about dinoflagellates? Tiny water bugs with super cool cellular architecture?
Check out this cool initiative from my colleague @manondemulder.bsky.social and her friends!
Their 1st online seminar is next month, don't miss it!
Check out this cool initiative from my colleague @manondemulder.bsky.social and her friends!
Their 1st online seminar is next month, don't miss it!
Re-redeading this one 📖. Great book for evolution and bioenergetics aficionados. The view is a bit distracting though ⛵
May 19, 2025 at 1:28 PM
Re-redeading this one 📖. Great book for evolution and bioenergetics aficionados. The view is a bit distracting though ⛵
Reposted by Florent Waltz
Happy to present the lab latest work, today from the green-side. The ultimate PSII assembly intermediate that directly precedes incorporation of the Mn4O5Ca cluster and formation of the OEC. Psb32 binds to PsbV, challenging the assumption the extrinsic subunits all associate spontaneously in-vivo.
May 12, 2025 at 5:50 AM
Happy to present the lab latest work, today from the green-side. The ultimate PSII assembly intermediate that directly precedes incorporation of the Mn4O5Ca cluster and formation of the OEC. Psb32 binds to PsbV, challenging the assumption the extrinsic subunits all associate spontaneously in-vivo.
Reposted by Florent Waltz
“The Website” is here! It can be intimidating getting into analysis of #CryoET data, and software is evolving all the time👩💻🚀. @phaips.vd.st & @florentwaltz.bsky.social put our lab’s workflows into an online guide. We hope this helps lower the bar to joining #TeamTomo. Feedback much appreciated! 🧪🧶🧬🔬
Hey #TeamTomo,
Ever been in need of a tutorial about the fundamentals of cryo-electron tomography? From preprocessing raw frames to high-res subtomogram averaging?
That's why @florentwaltz.bsky.social and I made this website!
tomoguide.github.io
Follow the thread 1 /🧵
#CryoET #CryoEM 🔬🧪
Ever been in need of a tutorial about the fundamentals of cryo-electron tomography? From preprocessing raw frames to high-res subtomogram averaging?
That's why @florentwaltz.bsky.social and I made this website!
tomoguide.github.io
Follow the thread 1 /🧵
#CryoET #CryoEM 🔬🧪
Welcome to TomoGuide
A step-by-step Cryo-ET guide
tomoguide.github.io
May 7, 2025 at 10:56 AM
“The Website” is here! It can be intimidating getting into analysis of #CryoET data, and software is evolving all the time👩💻🚀. @phaips.vd.st & @florentwaltz.bsky.social put our lab’s workflows into an online guide. We hope this helps lower the bar to joining #TeamTomo. Feedback much appreciated! 🧪🧶🧬🔬
You want to start tomography? Solve structures inside cells? Reach Nyquist 😳 ? @phaips.vd.st and I have a website for you! tomoguide.github.io
You'll find a tutorial on how to reconstruct tomograms, pick particles and do subtomogram averaging, using different software!
Hope it will be useful !
You'll find a tutorial on how to reconstruct tomograms, pick particles and do subtomogram averaging, using different software!
Hope it will be useful !
May 6, 2025 at 4:42 PM
You want to start tomography? Solve structures inside cells? Reach Nyquist 😳 ? @phaips.vd.st and I have a website for you! tomoguide.github.io
You'll find a tutorial on how to reconstruct tomograms, pick particles and do subtomogram averaging, using different software!
Hope it will be useful !
You'll find a tutorial on how to reconstruct tomograms, pick particles and do subtomogram averaging, using different software!
Hope it will be useful !
Reposted by Florent Waltz
Hey #TeamTomo,
Ever been in need of a tutorial about the fundamentals of cryo-electron tomography? From preprocessing raw frames to high-res subtomogram averaging?
That's why @florentwaltz.bsky.social and I made this website!
tomoguide.github.io
Follow the thread 1 /🧵
#CryoET #CryoEM 🔬🧪
Ever been in need of a tutorial about the fundamentals of cryo-electron tomography? From preprocessing raw frames to high-res subtomogram averaging?
That's why @florentwaltz.bsky.social and I made this website!
tomoguide.github.io
Follow the thread 1 /🧵
#CryoET #CryoEM 🔬🧪
Welcome to TomoGuide
A step-by-step Cryo-ET guide
tomoguide.github.io
May 6, 2025 at 4:27 PM
Hey #TeamTomo,
Ever been in need of a tutorial about the fundamentals of cryo-electron tomography? From preprocessing raw frames to high-res subtomogram averaging?
That's why @florentwaltz.bsky.social and I made this website!
tomoguide.github.io
Follow the thread 1 /🧵
#CryoET #CryoEM 🔬🧪
Ever been in need of a tutorial about the fundamentals of cryo-electron tomography? From preprocessing raw frames to high-res subtomogram averaging?
That's why @florentwaltz.bsky.social and I made this website!
tomoguide.github.io
Follow the thread 1 /🧵
#CryoET #CryoEM 🔬🧪
Reposted by Florent Waltz
Also want to highlight that the script is based on the awesome aretomo3torelion5 from @phaips.vd.st 🤩
github.com/Phaips/areto...
github.com/Phaips/areto...
GitHub - Phaips/aretomo3torelion5
Contribute to Phaips/aretomo3torelion5 development by creating an account on GitHub.
github.com
April 28, 2025 at 1:16 PM
Also want to highlight that the script is based on the awesome aretomo3torelion5 from @phaips.vd.st 🤩
github.com/Phaips/areto...
github.com/Phaips/areto...
Reposted by Florent Waltz
To all #ChlamyDataset enthusiasts, here is a script that lets you directly import the pre-processed results from EMPIAR-11830 into #RELION v5 for subtomogram averaging:
github.com/Chromatin-St...
#Chlamydomonas #TeamTomo #CryoET #OpenSoftwareAcceleratesScience
github.com/Chromatin-St...
#Chlamydomonas #TeamTomo #CryoET #OpenSoftwareAcceleratesScience
ChlamyAnnotations/chlamydataset2relion5 at master · Chromatin-Structure-Rhythms-Lab/ChlamyAnnotations
Particle annotations for the large-scale cryo-ET dataset of Chlamydomonas reinhardtii - Chromatin-Structure-Rhythms-Lab/ChlamyAnnotations
github.com
April 28, 2025 at 1:16 PM
To all #ChlamyDataset enthusiasts, here is a script that lets you directly import the pre-processed results from EMPIAR-11830 into #RELION v5 for subtomogram averaging:
github.com/Chromatin-St...
#Chlamydomonas #TeamTomo #CryoET #OpenSoftwareAcceleratesScience
github.com/Chromatin-St...
#Chlamydomonas #TeamTomo #CryoET #OpenSoftwareAcceleratesScience
Reposted by Florent Waltz
1/5: Over the last few months, I have been working on an update for the #FollowRelionGracefully dashboard, which offers improved real-time job previews for #cryoEM #Relion jobs.
April 27, 2025 at 8:49 PM
1/5: Over the last few months, I have been working on an update for the #FollowRelionGracefully dashboard, which offers improved real-time job previews for #cryoEM #Relion jobs.
Check out the latest version of MemBrain, spearheaded by computation superstar @lorenzlamm.bsky.social ! It can segment, pick particles and give you metrics on everything!
🦠🧠 MemBrain update! 🧠🦠
We’ve updated our preprint! It now covers the full MemBrain v2 pipeline for end-to-end membrane analysis in #CryoET: segmentation, particle picking, and spatial statistics.
🔗 Preprint: doi.org/10.1101/2024...
🔗 Code: github.com/CellArchLab/...
🧵(1/6) #TeamTomo
We’ve updated our preprint! It now covers the full MemBrain v2 pipeline for end-to-end membrane analysis in #CryoET: segmentation, particle picking, and spatial statistics.
🔗 Preprint: doi.org/10.1101/2024...
🔗 Code: github.com/CellArchLab/...
🧵(1/6) #TeamTomo
April 25, 2025 at 10:25 AM
Check out the latest version of MemBrain, spearheaded by computation superstar @lorenzlamm.bsky.social ! It can segment, pick particles and give you metrics on everything!
Reposted by Florent Waltz
🦠🧠 MemBrain update! 🧠🦠
We’ve updated our preprint! It now covers the full MemBrain v2 pipeline for end-to-end membrane analysis in #CryoET: segmentation, particle picking, and spatial statistics.
🔗 Preprint: doi.org/10.1101/2024...
🔗 Code: github.com/CellArchLab/...
🧵(1/6) #TeamTomo
We’ve updated our preprint! It now covers the full MemBrain v2 pipeline for end-to-end membrane analysis in #CryoET: segmentation, particle picking, and spatial statistics.
🔗 Preprint: doi.org/10.1101/2024...
🔗 Code: github.com/CellArchLab/...
🧵(1/6) #TeamTomo
April 25, 2025 at 7:28 AM
🦠🧠 MemBrain update! 🧠🦠
We’ve updated our preprint! It now covers the full MemBrain v2 pipeline for end-to-end membrane analysis in #CryoET: segmentation, particle picking, and spatial statistics.
🔗 Preprint: doi.org/10.1101/2024...
🔗 Code: github.com/CellArchLab/...
🧵(1/6) #TeamTomo
We’ve updated our preprint! It now covers the full MemBrain v2 pipeline for end-to-end membrane analysis in #CryoET: segmentation, particle picking, and spatial statistics.
🔗 Preprint: doi.org/10.1101/2024...
🔗 Code: github.com/CellArchLab/...
🧵(1/6) #TeamTomo