Marvellous send off for @amartinezarias.bsky.social ‘s lab, perfectly located in Gaudi’s La Pedrera. I took no pictures as I was too busy hugging old friends, but the organisers incl @dias-andre.bsky.social pulled off something rly special. Community in science is the real joy of the work we do! 💕

🧫Looking for a PhD to start Autumn 2025? We're recruiting! 🧪

The project will focus on using #embryomodels to explore #development & could cover a range of specific questions. Please RT! 🙏

Apply via the portal, and get more details here: www.crick.ac.uk/careers-stud...

Thus, we found feedback in both directions, causing patterning important for organogenesis. The simple ‘modularity’ of hTLS that let us investigate in the presence/absence of certain tissues, could help us understand co-development, esp in a human context (6/7)

So we looked at signalling between the 2 tissues. As predicted from animals, RA is needed for PAX6+ but not neurogenesis. Plus, ALDH1A2 (which synthesises RA) was only in the medial somite - implying neural tube signalling was reciprocally patterning the somites! (5/7)

BUT without a notochord, hTLS are dorsal. Exposure to SAG makes them ‘ventralise’ dose-dependently. Doing this, we noticed something interesting… the NT cells next to the somites were different from the other side. Communication between tissues was setting up an axis... (4/7)

hTLS show self-organised wavefront signalling and oscillations to form somites; Neuromesodermal progenitors support elongation and become depleted over time; HOX genes show we’re at thoracic/lumbar regions… (3/7)

hTLS are an embryo model that mirrors development using human cells. We used 7 cell lines + optimised to make it robust. The neural tube forms through a 2ndry neurulation-like process. Bioinformatically, hTLS cells are most like Carnegie Stage13-14 embryos (~day 28!) (2/7)

Have you ever wondered how your back formed? The human embryo makes a neural tube (future spinal cord) and somites (trunk muscle/bone) from ~d20. They’re formed at the same time and place, so we used human Trunk-like Structures (hTLS) to investigate their ‘co-development’… (1/7)