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Reposted by Katrina Velle

Wout Oosterheert @woutoosterheert.bsky.social · 1d

Very excited that my final postdoctoral work is now online in Cell @cellpress.bsky.social.

www.sciencedirect.com/science/arti...

Using 16 (!) cryo-EM structures, we uncovered how the three proteins coronin, cofilin and AIP1 work together to rapidly disassemble actin filaments.

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Mark Peifer (He, him) @peiferlabunc.bsky.social · 18h

Incredible video, incredible work. This is a huge step forward in understanding both actin severing, and more broadly, how actin binding proteins change filament architecture and thus drive re-modeling 🧪

Wout Oosterheert @woutoosterheert.bsky.social · 1d

Very excited that my final postdoctoral work is now online in Cell @cellpress.bsky.social.

www.sciencedirect.com/science/arti...

Using 16 (!) cryo-EM structures, we uncovered how the three proteins coronin, cofilin and AIP1 work together to rapidly disassemble actin filaments.

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Katrina Velle @katrinavelle.bsky.social · 6d

Happy #MicrosCreepy season!

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Katrina Velle @katrinavelle.bsky.social · 6d

And a flagellate swimming! (In ficoll to slow it down- it’s doing its best!)

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Katrina Velle @katrinavelle.bsky.social · 6d

Yup! Here’s an amoeba crawling:

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Katrina Velle @katrinavelle.bsky.social · 8d

I have been slacking on the #microscreepy season! Thanks for reposting!

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Katrina Velle @katrinavelle.bsky.social · 8d

Thanks for reposting!

Katrina Velle @katrinavelle.bsky.social · 8d

They are both Naegleria gruberi— they are normally amoebae, but can transiently transform into a flagellate as a stress response

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Katrina Velle @katrinavelle.bsky.social · 8d

PhD or Master's position available for Fall 2026!

Interested in how actin drives cell crawling, eating, dividing, or osmoregulation? What about pathogenesis of a brain-eating amoeba? Or eukaryotic evolution? If so, apply through my website: katrinavelle.wixsite.com/science/cont...
Please share!

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Reposted by Katrina Velle

Theory of Living Matter Group @tlmcambridge.bsky.social · 10d

🚨 TLM Online Seminar Series - 08.10.25 | 16:00 UK
Pablo Sáez: "Decision-making during cell migration"

Please repost & to attend online please register to our 📧for the zoom link: lists.cam.ac.uk/sympa/subscr...

Poster with a picture of the speaker, Pablo Saez, advertising his talk: Decision Making during cell migrations. Abstract: Moving cells navigate inside living tissues often encountering obstacles and junctions, where their path branches into alternative directions of migration. This is the case of cells moving on top or within blood vessels, which often bifurcate into branches. Cells have diverse migratory strategies that differentially rely on the adhesion to the substrate. Cells that undergo mesenchymal migration are highly dependent on the adhesion to the substrate, and when facing bifurcations are forced to coordinate the adhesion and detachment of the competing branches. Recent studies showed how the decision is made -to keep or retract a branch and choose a new direction- when there is bias: open versus dead-end, differences in pressure, presence/absence of a chemoattractant. However, much less is know about how cells decide a new direction when the decision is unbiased. Similarly, it is poorly understood how migrating cells coordinate membrane dynamics during branching to maintain a good trade-off between microenvironmental exploration and migratory efficiency. Here, we use in vitro live-cell imaging using different levels of complexity, and advanced image analysis to analyze the response of migrating cells when facing symmetric junctions, and extreme branching when cells simultaneously face several bifurcations. We found that actin and membrane dynamics play a key role to choose a new direction path in both cases i) when cells face a single junction (Ron et al. 2024), and ii) when cells exhibit high levels of branching because they face several junctions at the same time (Liu et al.). In addition, we found that migrating immune cells have a fine tune regulation of branching in order to coordinate surveillance and migration. These results shed light on the mechanisms by which cells resolve unbiased junctions and branching during cell migration.

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Reposted by Katrina Velle

Ankita Jha @ankita13jha.bsky.social · 15d

If anyone ever wants to brush up on a lot of cell migration concepts don't forget we have several wonderful scientists who have given talks previously in cell migration seminars. I find it so comforting to go look at old videos, maybe someone else who will do as well!!
youtube.com/@cellmigrati...

Cell Migration Seminars

Cell Migration Seminars every Tuesday at 16:00 BST.

youtube.com

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Reposted by Katrina Velle

Michael Way @drmichaelway.bsky.social · 28d

And now for something completely different @tianyang22.bsky.social & #YanCao uncover of how SPIN90 dimers activate Arp2/3 to nucleate bidirectional linear actin filaments. Great collaboration with @romet-jegou-lab.bsky.social & @carolynmoores1.bsky.social #Cryo-EM #Arp2/3 rdcu.be/eGoH4

Arp2/3-mediated bidirectional actin assembly by SPIN90 dimers

Nature Structural & Molecular Biology - Liu et al. show that SPIN90 dimerizes and binds two Arp2/3 complexes to nucleate two bidirectional actin filaments and the dimerization domain is...

rdcu.be

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Katrina Velle @katrinavelle.bsky.social · 28d

”Please inhibit responsibly: Natural and synthetic actin toxins as useful tools in cell biology”

I had a lot of fun going down different actin inhibitor rabbit holes with @onishilab.bsky.social on this perspective!

www.molbiolcell.org/doi/10.1091/...

www.molbiolcell.org/cms/10.1091/...

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Reposted by Katrina Velle

Journal of Cell Biology @jcb.org · Sep 12

@fritzlaylin.bsky.social et al. propose a simple way to highlight both experimental #reproducibility & cell-to-cell variation, while avoiding pitfalls common in analysis of cell biology data rupress.org/jcb/article/...

📕 Reproducibility & Best Practices in Cell Biology: rupress.org/jcb/collecti...

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Reposted by Katrina Velle

Shashank Shekhar lab @sshekhr.bsky.social · Aug 29

📢📢Hiring 2 Research Assistants & 2 Postdocs at Emory University in Atlanta to study cytoskeletal biophysics/biochemistry. Please RT.

RAs: great for recent bachelor's/master's in Physics/Bio/Chem/Biochem. Email CV and interests to [email protected].

More info: www.shekharlab.org

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Reposted by Katrina Velle

Maitreyi Das @daslabpombe.com · Sep 6

Our latest preprint on the role of the Arp2/3 complex in mitotic entry is now available @biorxiv. This work was done by Dhanya Kalathil, a very talented postdoc in my lab. The story started in 2019 when we were investigating the role of branched actin in cytokinesis. 1/

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Reposted by Katrina Velle

Current Biology @currentbiology.bsky.social · Aug 28

Feeling mitochondrially challenged lately?

Here are two classic reviews on #mitochondria that should help.

www.cell.com/current-biol...

www.cell.com/current-biol...

The Origin and Diversification of Mitochondria

Moving beyond the simplistic view of mitochondria as the power house of the cell, Roger et al. present the immense diversity of mitochondria and mitochondrial functions across eukaryotes, and bring th...

www.cell.com

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Reposted by Katrina Velle

Nature @nature.com · Aug 27

For some three billion years, unicellular organisms ruled Earth. Then, around one billion years ago, a new chapter of life began

go.nature.com/3JyRV4S

How did life get multicellular? Five simple organisms could have the answer

Single-celled species that often stick together in colonies have researchers rethinking the origin of animals.

go.nature.com

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Katrina Velle @katrinavelle.bsky.social · Aug 28

I'm growing (pun intended) pretty fond of the idea. Maybe at some point this semester!

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Katrina Velle @katrinavelle.bsky.social · Aug 28

Hey @arzaf.bsky.social how about a side project? 😄

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Reposted by Katrina Velle

Luc Reym⌬nd @lreymond.bsky.social · Aug 28

New preprint online!

So much fun working on this project, thank you @centriolelab.bsky.social and @dudinlab.bsky.social for embarking me on this one!

Hopefully HAK-actin will become your best companion for actin staining U-ExM expanded samples.

Paul & Virginie - Centriole Lab @centriolelab.bsky.social · Aug 28

Trouble imaging actin in ExM? Meet HAK-Actin, a probe for U-ExM, cryo-ExM & iU-ExM. Enables post-expansion labeling for max signal. www.biorxiv.org/content/10.1...
Soon at @spirochrome.com
Led by O.Mercey and @lreymond.bsky.social, in collab with @dudinlab.bsky.social and @marinelap.bsky.social

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Reposted by Katrina Velle

Pablo J. Sáez @pjsaez.bsky.social · Jun 20

#FluorescenceFriday

#Mitochondria, powerhouse of the #cell were labeled (cyan) and it's possible to visualize how they reach *every* corner to provide energy.

All recorded under the microscope @cellcommlab.bsky.social

#scicomm #sciencesky #microscopy #organelles @focalplane.bsky.social 🧪🔬

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Barry Bentley, PhD, FRSB @bbentley.bsky.social · Jun 18

Who needs BioRender when you have #MSPaint?

www.cell.com/cell/abstrac...

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American Society for Cell Biology @ascbiology.bsky.social · Jun 9

Today, @nihfellowsunited.bsky.social staff sent a powerful letter to the NIH Director outlining serious concerns about the agency’s direction. Thousands have already signed in support—add your name. – Mary Munson, ASCB President www.standupforscience.net/bethesda-dec...

Bethesda Declaration — STAND UP FOR SCIENCE

Support NIH Staff Now!

www.standupforscience.net

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Jeremy Berg @jeremymberg.bsky.social · Jun 10

Glad to see some scientific society leadership stepping up to endorse the #BethesdaDeclaration

American Society for Cell Biology @ascbiology.bsky.social · Jun 9

Today, @nihfellowsunited.bsky.social staff sent a powerful letter to the NIH Director outlining serious concerns about the agency’s direction. Thousands have already signed in support—add your name. – Mary Munson, ASCB President www.standupforscience.net/bethesda-dec...

Bethesda Declaration — STAND UP FOR SCIENCE

Support NIH Staff Now!

www.standupforscience.net

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