Thank you!

Thanks a lot Uli!

Thank you! 😁

Thanks a lot Pedro!! 😁

Thank you Alison!

and in collaboration with @mfnberlin.bsky.social, Jack Ullrich-Lüter, Jil Carl, Maria Schauer, Anne-C. Zakrzewski, Berit Zemann, Carsten Lüter, @biodev-vlfr.bsky.social @croce-urchin.bsky.social, Tiphaine Sancerni, Oğuz Akar, @igflyon.bsky.social, @almazan.bsky.social #ScienceAdvancesResearch

With @szndohrn.bsky.social @danivoronov.bsky.social , @mlrusciano.bsky.social , @mariacocurullo.bsky.social, Filomena Caccavale, Giovanna Benvenuto

Long considered brainless creatures, our results provide evidence that sea urchins possess a highly photosensitive nervous system organized in an “all-brain” manner instead.

Adding to this complexity, we discovered a vast array of photoreceptor cells with a conserved retinal molecular fingerprint, as well as a population expressing a rare combination of opsins that we hypothesize is an ideal candidate for non-ocular sea urchin vision.

Moreover, we found that the postmetamorphic nervous system, remarkable for its cell type diversity and complexity, also exhibits a head-like molecular signature and expresses vertebrate brain gene homologs.

Based on our findings, we report that the sea urchin juvenile body plan is head-like, similar to what has previously been demonstrated in sea stars and brittle stars, suggesting that echinoderms in general are predominantly head-like organisms.

By comparing juvenile and larval cell types, we identified those that retain developmental molecular signatures and gene regulatory fingerprints, as well as juvenile-specific ones.

With this project, funded by @hfspo.bsky.social, we identified the cell type repertoire of the postmetamorphic sea urchin juvenile at a single nucleus level.