• Figure 1 of the article: Fig. 1. Phase diagram of tissue material phase transitions and examples. (A) Schematic diagram showing how continuous changes in microscopic dynamics (control parameter) lead to abrupt, drastic, and non-linear shifts in macroscopic properties that define the material response (order parameter). (Aa-Ab) Exemplary phase transitions as traditionally described in non-living matter, e.g. for water (Aa), as well as in living matter, e.g. for embryonic tissues (Ab). Yellow areas indicate fluid-like tissues and regimes. Blue areas indicate solid-like tissues and regimes. Magenta dashed line depicts the critical point. Orange line marks particle and cell trajectories.

Tissue phase transitions in development: more than just mechanics

In this Review, @nicolettapetridou.bsky.social, @laura-rustarazo.bsky.social and @karengrace12.bsky.social discuss tissue phase transitions during development: doi.org/10.1242/dev....

Hi Kaitlin, I have sent you a DM.

If you are curious how PTs integrate scales in development - from molecules to tissues, from biochemical signals to physical forces - this review is for you.

Traditionally, tissue phase transitions (PTs) are seen as simple shifts in tissue deformability (fluid/solid), but recent work shows that they are dynamic processes interacting with signalling, growth, and patterning.

Tissue phase transitions in development: more than just mechanics Summary: Tissue material phase transitions are classically thought to regulate tissue deformability. This Review emphasises their unexpected roles in directly influencing growth and patterning signall...

Excited to share our new review in @dev-journal.bsky.social on tissue phase transitions during development!

@karengrace12.bsky.social @nicolettapetridou.bsky.social

🔗 doi.org/10.1242/dev....

Abstract deadline extension alert! 🚨 You now have until 25 November to submit your abstract and be one of 22 selected short talk speakers for #EESCollectivity ➡️ s.embl.org/ees26-01-bl

Explore how collective behaviours arise from fundamental principles across biological systems. 🦠🐒🧬

An unexpected topic I encountered during my PhD: tricellular junctions.

I first knew them as local regulators of tissue mechanics, but over time have realised their broader impact at the tissue scale.

I wrote a brief overview of this in a thread for @epimechfc.bsky.social.

Feb 1 deadline approaching for our @kitp-ucsb.bsky.social QBio summer course on Physical Principles of Morphogenesis in Plants and Animals. @streichan.bsky.social
@maurazimmermann.bsky.social @maizel-lab.org @yusuke-mori.bsky.social @akankshi.bsky.social @nicolettapetridou.bsky.social

What a year it's been at the DB unit @embl.org! 2025 brought us hard work, exciting discoveries, and numerous initiatives that advanced our science. As we wrap up this year, we want to wish everyone a restful and joyful winter break.
We'll be back in 2026, ready for new challenges. See you then! 🎉

You only have one more week to submit your abstract for 'Collectivity in living systems: emergence, function, and evolution' 👉 s.embl.org/ees26-01-bl

Don't miss #EESCollectivity which will explore how collective behaviours arise from fundamental principles across biological systems🦠🐒🧬

⚡ Check out the lab's latest preprint - beautiful work by @cami-autorino.bsky.social ⚡

Join this week's VGZT seminar to explore evo-devo in eels and how rigidity transitions shape embryonic tissue organization! 🐟

Adhesion-driven tissue rigidification triggers epithelial cell polarity The active regulation of tissue material properties via phase transitions is central in morphogenesis. Transitions abruptly occur at critical points in diverse control parameters, including cell densi...

🔗 You can read the full story here:
www.biorxiv.org/content/10.1...
#DevBio #Mechanobiology #Biophysics

⚡️Overall, we find that the pluripotent embryo can change its morphogenetic trajectory based on the type of material state phase transitions it undergoes.

⚡️This suggests that phase transitions are not simple modulators of tissue deformability, but actively impact the tissue morphogenetic potential.

7/ The discretization of tissue morphologies driven by the phase transition control parameters is also reflected at the molecular level: When adhesion-driven solidification is uncoupled from jamming, tissues form lumens and acquire epithelial polarity.

6/ Simulations and experiments show how by uncoupling vs. coupling changes in cell density and adhesion, tissues dramatically change their morphology. This is mainly due to a porous to non-porous transition, occurring at the adhesion critical point as tricellular junctions close.

5/ By measuring tissue viscosity and cell contact dynamics, we find that adhesion alone determines the material state. If the critical point in adhesion is crossed, the tissue will be solid-like, independently of cell density. Then, what’s the importance of the other parameters?

4/ We establish #optogenetic and pharmacological tools to experimentally engineer pluripotent tissues to undergo material phase transitions using different combinations of the control parameters. How does each parameter contribute to tissue rheology?

3/ We study this in the pluripotent #zebrafish early embryo, where three parameters – cell adhesion, density, and connectivity – shift together during a fluidization transition, crossing their respective critical points. But can these parameters be uncoupled?

2/ Unlike inert materials, living tissues transition between fluid and solid states by dynamically tuning a variety of control parameters, like cell shape, adhesion and density. Does this multiplicity of control parameters matter for biological function?

1/ We investigate how the way that a tissue transitions from a fluid- to a solid-like material state - an essential process in development, wound healing, and disease - can impact its organization at the morphological and even molecular level.

🎉 Excited to share our new work: “Adhesion-driven tissue rigidification triggers epithelial cell polarity”, now on @biorxivpreprint.bsky.social !

A huge thank you to @nicolettapetridou.bsky.social, Bernat, @crisp-c.bsky.social, Adrián, and everyone involved! 🙌

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