Martin Loose

Feedback and comments are very welcome!

This suggests that FtsZ's disordered C-terminal linker may encode geometric information and that this could have an evolutionary role!

Marko also found that "diluting" the CTL in a filament, by mixing WT FtsZ and a version without linker, drastically reduces ring diameter:

In vitro, increasing the charge segregation in the linker increased filament curvature and decreased Z-ring size! Treadmilling dynamics were unaffected.

We examined ~4,600 FtsZ sequences and found that charge segregation in the disordered CTL appears to correlate with cell width across species: FtsZ from wider bacteria tends to have more uniform charge distribution in the linker, whereas high charge segregation is mostly found in skinny cells.

Charge segregation in the C-terminal linker of FtsZ enables Z-ring scaling with prokaryotic cell width Bacterial cytokinesis is orchestrated by the Z-ring, a cytoskeletal structure formed by treadmilling filaments of the tubulin-like GTPase FtsZ. During assembly, filament curvature must match the cell ...

Happy to share a new preprint from the lab: Marko became interested in whether the disordered linker of FtsZ might influence how the protein organizes into the Z-ring. And this led to some surprising findings!
Preprint: www.biorxiv.org/content/10.1...

Our fully-funded PhD program is open for applications!

Join us to conduct cutting-edge research at top facilities with guidance from world-class faculty. Through our interdisciplinary training, you can tailor your PhD experience to match your interests and curiosity.

Apply now: phd.ista.ac.at

Tenure-based Research Staff Scientist Position in Computational Structural Biology ISTA (www.ista.ac.at) is seeking a highly skilled Staff Scientist in Computational Structural Biology to support and advance the Institute’s structural biology research through the development and imp...

here is the correct link: ista.ac.at/en/job/tenur...

Great, looking forward!

The Institute of Science and Technology Austria (ISTA) @istaresearch.bsky.social is hiring a tenure-track staff scientist in Computational Structural Biology (cryo-EM, cryo-ET, structural prediction methods, image analysis)!

More info here: apply.ista.ac.at/comp_structu...

Mechanistic adaptation of the metazoan RabGEFs Mon1-Ccz1 and Fuzzy-Inturned The molecular comparison of related RabGEFs reveals adaptation mechanisms of a functional module for specific cellular tasks.

Thrilled to share our newest publication in Science Advances!
We uncovered how two RabGEF complexes — Mon1-Ccz1 and Fuzzy-Inturned — adapt to regulate distinct Rab GTPases despite their structurally conserved catalytic core.
www.science.org/doi/full/10....

*salary is € 1,523* gross/month!

Master Thesis Position – Loose Research Group Our Group The Loose lab at the Institute of Science and Technology Austria (ISTA) is looking for a highly motivated Master student to join our research on the in vitro reconstitution of signaling n...

We are looking for a Master’s student to join a project on in vitro reconstitution of signaling networks in pathogen–host interactions: combine protein biochemistry, fluorescence microscopy & image analysis. Deadline: September 15.
Find out more and apply here: ist.ac.at/en/job/maste...

Postdoc Research Group Schur The Schur lab at the Institute of Science and Technology Austria (ISTA) has an open postdoc position for a highly motivated candidate to be part of our ERC-funded project ActinID. Our Group ...

We're hiring a postdoc!
Join our ActinID project to explore an uncharacterized actin-binding protein.

- Background in cell and/or structural biology?
- Eager to bridge both fields?

Get in touch if you're curious or have questions!
#cellbiology #cryoEM #cryoET #actin

ista.ac.at/en/job/postd...

Thank you, Thibaut!

We’re excited to share this story and would love your feedback!

The discovery of dynamic instability in a non-polar filament also raises key mechanistic questions: how are such filament dynamics generated, and how do these polymers shape cells?

These findings challenge the idea that ParMR systems are limited to plasmid segregation. Their plasticity may have enabled other functional innovations across evolution.

and another surprising discovery was that the cell division inhibitor MinC has acquired a second role in these Cyanobacteria: MinC evolved to now also disassemble CorM filaments, a striking case of functional expansion!

Benjamin was also able to acquire fantastic live cell movies of CorM filament dynamics:

In vitro reconstitution & cryo-EM show CorM forms dynamically instable, non-polar filaments—an architecture distinct from all known actin- or tubulin-based systems!

We built the first comprehensive phylogeny of ParMR systems, uncovering transitions from plasmids to chromosomes and unexpected functional diversity across the tree of life.

By combining structural, evolutionary, in vitro reconstitution and cell biology approaches we uncovered a new cytoskeletal system - called CorMR - that evolved from a ParMR system.

This project was initiated and led by fantastic postdoc Benjamin Springstein, @huepfkiesel.bsky.social in a collaboration with the labs of Florian Schur (cryo-EM)
@schurlab.bsky.social at ‪@istaresearch.bsky.social‬ and Daniela Megrian (phylogenetics) from ‪@ipmontevideo.bsky.social‬

Evolutionary repurposing of a DNA segregation machinery into a cytoskeletal system controlling cyanobacterial cell shape Bacteria, despite their diversity, use conserved cytoskeletal systems for their intracellular organization. In unicellular bacteria, the ParMRC DNA partitioning apparatus is well known for forming act...

One of the most exciting discoveries from our lab so far is now online as a preprint!

Read a story on how the ParMR and Min systems started to collaborate to create the CorMR cytoskeleton, which now controls cell shape in multicellular cyanobacteria:
www.biorxiv.org/content/10.1...

Looking for a student or postdoc!

Want to combine evolutionary analysis + structural modeling with in vitro biochemistry & fluorescence microscopy?
Help us uncover new protein-protein interactions — from in silico to in vitro.

Join us at @istaresearch.bsky.social 👉 looselab.org
🧬💡🔬🎡

Very cool findings from Paula, Andrea et al.! Excited that my student Roman could contribute! See Andrea’s thread below for more details:

🚨👉 Please check our recent work on bacterial cell division. In situ Cryo-ET reveals the cellular function of the penicillin binding protein 1b supported by AFM, live-cell imaging, in silico AlphaFold proteome screen and TIRFM. Hope you enjoy the read! #teamtomo #cryo-ET ❄️🔬🐎 big thanks to the team!

👉🏻https://ist.ac.at/en/education/postdocs/

who doesn't enjoy some beautiful FtsZ rings on a sunday evening? these from 𝘚𝘵𝘢𝘱𝘩𝘺𝘭𝘰𝘤𝘰𝘤𝘤𝘶𝘴 𝘢𝘶𝘳𝘦𝘶𝘴, from all angles, by the @jwveening.bsky.social, posted earlier on 𝕏, on may 6, 2021

Movie S2 from journals.plos.org/plospathogen...
#MicroSky