Jana Kroll

Postdoctoral Positions in Protein Engineering Post a job in 3min, or find thousands of job offers like this one at jobRxiv!

We got a large Helmholtz Bioengineering grant with Oliver Daumke, Artur Yakimovich, Alina Bazarova, and Dietrich Ruess to use protein design to target cancer.

Five open postdoctoral positions in Generative AI & Protein Engineering. Share & apply!

jobrxiv.org/job/max-delb...

Thank you so much! 😊

Group Leader in Biomedical Engineering at the @mdc-berlin.bsky.social in Berlin.

It's a broad call for whoever is doing exciting Bioengineering, please apply or share. We have a great institute with amazing colleagues and core facilities,highly recommend

application.mdc-berlin.de/site/index.p...

Postdoc program at the MDC in Berlin, @mdc-berlin.bsky.social : take a look 👇👇

For this call, collaborative projects between two groups will be funded. Take a look at the call and the groups and drop me an email if interested. Share with colleagues too!

www.mdc-berlin.de/postdocs#t-g...

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Excitation This image captures a mouse hippocampal neuron surrounded by numerous extensions that connect to other neurons via synapses. The cultured cell is equipped with a yellow fluorescent sensor for the neurotransmitter glutamate, which is normally used at room temperature. In this case, the image was captured at -170 °C using CFcryo-EM (Core Facility for Cryo–Electron Microscopy). Image: Dr. Jana Kroll, Daumke Lab

scientific image

Starfish Puts Motion Back in the Ocean This image shows starfish embryos that are only a few days old, using their tiny tentacles to create currents that visually and mathematically reflect the Earth’s magnetic field. The living embryo on the left of the image – unlike the immobile, dead embryo on the right – is actively shaping its fluid environment. The image was captured using bright-field microscopy and fluorescent particles. Image: Dr. Rafael Deliz Aguirre, Coscia Lab

🏆 Images from #mdcBerlin received top honors in the @helmholtzimaging.bsky.social “Best Scientific Image Contest”!

Jury Award for @janakroll.bsky.social, Daumke Lab
Public Choice Award for Dr. Rafael Deliz Aguirre, @coscialab.bsky.social

Full details: www.mdc-berlin.de/news/news/tw...

We have a preprint for you

EHD2 forms rings on caveolae necks, in contrast to most EHDs forming helices. We determined its structure on membranes and show that N-term acts as a spacer

By Elena, Vasya @vasiliimikirtumov.bsky.social, Jeff &Oli Daumke www.biorxiv.org/content/10.1...

What an inspiring morning at the CatCat Symposium! Thank you so much for inviting me @gallegolab.bsky.social and @felixmendu.bsky.social, it's been a pleasure visiting you in Barcelona 😊

In the left image, I see a queen with a crown🫅 But I guess that's not what you meant? 😅

So many amazing images! 🤩 🤩🤩

Please make sure to vote, mine is also in the list 😎

A broad call for a PhD researcher/ postdoc in our group at the MDC in Berlin. An ideal PhD student - a computational scientist, a postdoc - a structural biologist, but feel free to re-convince me!

We extended the deadline for after Easter, Apr 24th. Apply here www.mdc-berlin.de/career/jobs/...

PhD /Postdoc in In Situ Structural Biology by Cryo-ET Post a job in 3min, or find thousands of job offers like this one at jobRxiv!

We are looking for a PhD student/Postdoc to develop methods of cryo-ET and/or study the structure and function of membrane proteins. Great team at the MDC in Berlin.

It's a broad call, please apply and share!
jobrxiv.org/job/max-delb...

Program of the 9th CATCAT morning on "Dynamics in biology, from molecules to tissues", May 26th 2025

Together with @gallegolab.bsky.social we are organizing the next CATCAT morning on "Dynamics in biology, from molecules to tissues", with an amazing lineup of local and international speakers. If in Barcelona on May 26th, don't miss it, it's free! www.catcat-celltissuebiology.cat/event/9th-ca...

Cryo-confocal microscopy of a neuron expressing the glutamate sensor iGluSnFR 🥶 The neuron was optogenetically stimulated and subsequently plunge-frozen to preserve the high fluorescence intensity indicating neurotransmitter release. #FluorescenceFriday

Thank you!

The video shows more than 50 snapshots of vesicle fusion events in synapses, sorted by fusion progression 😎

Thank you! 😊

Thank you!

Thank you!

... but also between vesicles and cytoskeletal fibers likely resembling actin.

We did not only observe filamentous connectors at vesicles but also between vesicles and fusion events....

We further quantified distributions and tethering of synaptic vesicles at the active zone. Tether numbers closely correlated to the distance between vesicle and membrane, but not to their respective fusion readiness.

Overall, we analyzed more than 400 tomograms of synapses and identified more than 50 vesicle fusion intermediates. We classified and morphometrically characterized them.

Beyond that, we were able to correlate the cryo-fluorescent signal of iGluSnFR3 with a tomogram of a neuronal synapse. The arrowhead points to a putative vesicle fusion event.

We confirmed successful stimulation via cryo-confocal microscopy of the glutamate sensor iGluSnFR3. With this experiment, we also proved that fast fluorescent biosensors can be used under cryogenic conditions.

We developed a workflow for time-resolved in situ cryo-ET by coupling optogenetics with subsequent plunge freezing of neurons. Our setup allowed us to stimulate neurons only a few milliseconds before cryofixation.

First and foremost, thank you @icecoldsynapse.bsky.social, @mohsensadeghi.bsky.social, @mishakudryashev.bsky.social, Christoph, Lia, Gosia, Thiemo, Magdalena and Christian for your contributions!

Excited to share our new preprint "Dynamic nanoscale architecture of synaptic vesicle fusion in mouse hippocampal neurons" www.biorxiv.org/content/10.1...

We combine optogenetic stimulation of neurons with in situ cryo-ET to characterize membrane dynamics during synaptic vesicle fusion ❄️🔬⏱️

It's been a pleasure presenting my project at this fantastic workshop! ☺️ #EMBOinsitu

For me, the best part of research is discovering unexpected things. That’s exactly what happened while working on this project. I’m glad to see our story come to completion and excited about how many new questions it opens up!
www.pnas.org/doi/10.1073/...

Section through the 3D cryoET map of V-ATPase embedded in synaptic vesicle membrane at 17 Å resolution, as published in PNAS recently.

Oh my. This is just gorgeous from Misha Kudryashev's lab (I don't think he's here yet?). Love to see it. V ATPase resolved directly in synaptic vesicles 🤤 Lots of other neat observations in there also. Congrats to all involved! www.pnas.org/doi/10.1073/...