Nimesh Chahare

Synthetic materials accumulate damage with every mechanical challenge. Epithelial tissues are regularly loaded, yet healthy epithelia rarely rupture. Why?

We are @epmech.bsky.social and @baldaufsci.bsky.social and in this thread we introduce you to cyclic loading.

bsky.app/profile/epim...

Very happy that the first article from my postdoc work in the Tomancak lab is now published @PNAS! www.pnas.org/doi/10.1073/.... We studied the self-organization of actin in aggregates made from Hydra cells. Thread below (1/9)

Tissue bending through localized BM growth or dissolution.

Alteration in tissue morphology by intrinsic stresses in an assembling BM network.

Branching morphogenesis driven by localized deposition of interstitial matrix.

Asymmetric tissue expansion through anisotropic BM remodeling.

Maybe it's time we rethink the idea that development is a cell centric process? In this beautiful review, María-del-Carmen and @stramerlab.bsky.social discussed how the ECM underlies and influences many morphogenesis processes from wing unfolding to mammary gland development.
doi.org/10.1016/j.cd...

Hi bsky!

Do embryonic tissues have backup plans🔀? Gastruloids (model of body elongation) can build an axis through different cellular mechanisms when on adherent substrates instead of free floating. A case of developmental plasticity!

w/ A. Delahaye & ‪@bensteventon.bsky.social‬

shorturl.at/v01DO

🎉 Happy International #EpithelialMechanics Day! 🎉

If you’ve been following this account closely, you might already know methods to probe mechanics in vitro, but what about in live embryos?

I’m @amichaut.bsky.social, and I’m going to share a few great papers on this aspect of #EpithelialMechanics.

Check out this thread I wrote for @epimechfc.bsky.social ⬇️

Have you ever thought about inflating tissues?
Or maybe quickly deflating those inflated tissues?

New #EpithelialMechanics pre-print: doi.org/10.1101/2025...
🧵 with pressure control, multiscale buckling, controlled wrinkling

Thank you☺️

Thanks Neha! 😊

On cell extrusion in the #intestine!
After 80 years of observations, we finally took a deeper look thanks to 2D #organoids. We report:

3D #forces, #extrusion still only in the villus even without curvature, #lamellipodia generate 3D force.. and more. Have a look!
www.biorxiv.org/content/10.1...

Thank you, Julia! ☺️ #EpithelialMechanics forever 🤘

I'm very happy too! Moltes gràcies, Raimon 😊😊

Thank you, mathieu! 😊 😊

Thank you! 😊 akshar

🚨 Second preprint of the week!

We uncover the multiscale dynamics of active viscoelastic buckling in epithelia.

We harness these mechanical instabilities for synthetic morphogenesis.

Led by @onenimesa.bsky.social 🙌. Theory by Marino Arroyo etal. @ibecbarcelona.eu

www.biorxiv.org/content/10.1...

I want to acknowledge that it truly takes a village to conduct science and produce preprints. A huge thank you to my labs,
specifically Moli team: @tomgolde.bsky.social Thomas Wilson, @oozguc.bsky.social and
@xaviertrepat.bsky.social and Marino Arroyo!

Finally, we could use control of shape to rationally direct buckling into predictable wrinkle patterns.
9/10

image for multiscale buckling

Wait a min, same logic applies to the cell cortex, which is also surrounded by viscous cytosol, we predicted micron size wrinkles on the cell surface.

Guess what: Wrinkling is multiscale!
8/10

These shells are buckling in the viscous medium, so on deflation tissue deforms itself and the fluid medium around it. The pattern comes about as a result of this competition.
7/10

Pretty cool, what about the size, looking from the top, we see smaller shells buckle to form peripheral wrinkle while larger shells form radial folds. Why????
6/10

buckling phase diagram

We find that the buckling emerges for fast deflation relative to the cortex’s relaxation time, and is suppressed by high contractility.
5/10

Do they buckle?? Yes they do!!
Quality is low because this happens very fast!!
4/10

If we deflate the shell in steady state it will buckle!!!

Thanks to A Ouzeri, PK Bal, and Marino Arroyo for their awesome models of the active viscoelastic shell.
doi.org/10.1101/2025...
doi.org/10.1101/2025...

3/10

figure for microfluidic device

With our cool device: MOLI, we inflated the flat monolayer into a spherical shell! 2/10

Have you ever thought about inflating tissues?
Or maybe quickly deflating those inflated tissues?

New #EpithelialMechanics pre-print: doi.org/10.1101/2025...
🧵 with pressure control, multiscale buckling, controlled wrinkling

Morphodynamics of human early brain organoid development - Nature Human brain morphodynamics are explored using organoids.

Very happy to share it’s online! If you read the preprint, updates include tracking cells and tissue flow, Histo4i timecourse (69 Abs) comparing spatial patterning emergence and a new WLS KO ipsc line establishing mechanosensing via YAP-WLS/WNT caudalizes organoids www.nature.com/articles/s41...

How to turn a layer of fibroblasts into a tulip 🌷?

Check out our new pre-print on shape-programmable living surfaces.

Led by @pauguillamat.bsky.social‬

www.biorxiv.org/content/10.1...

Pigment cell movement is not required for generation of Turing patterns in zebrafish skin - Nature Communications Pigment pattern formation in zebrafish depends on the interactions between the pigment cells. Here the authors present a mathematical model based on mutual interaction of pigment cells in the absence ...

I worked on a group project that created a toy agent-based model simulating interactions between cells to form patterns. This project was inspired by a study on stripe formation in zebrafish, showing how simple cell interactions produce beautiful patterns in nature. www.nature.com/articles/nco...

I recently enjoyed an amazing EMBO workshop on computational modeling of multicellular systems in Barcelona. I learned various techniques & gained hands-on experience

Thanks to @embo.org @jamesasharpe.bsky.social @torres-sanchez.bsky.social for this wonderful workshop!

We did this 👇from scratch!