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Reposted by Giacomo Gattoni

The Integrative Biology of Brain Evolution (TIBBE)- Network @tibbe-evolneuro.bsky.social · Sep 4

🤩 Join us for the next TIBBE seminar:
Evolution of brain cell types.
September 10, 2–3pm UTC

This event brings together 2 outstanding evolutionary and developmental neuroscientists who will present their work, followed by an interactive discussion with the audience: www.crowdcast.io/c/evolution-...

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Giacomo Gattoni @giacomogattoni.bsky.social · Aug 26

Wanna learn more about the origin and evolution of a really cool cell type AND look at the brains of chicken, salamander, zebrafish, bichir and skate, all in one paper? 🧠🧬🤩

Check out our new preprint on the evolution of Cajal-Retzius cells, led by Eli Gumnit!!

Maria Antonietta Tosches @matosches.bsky.social · Aug 25

Excited to share our latest work on brain evolution, where we dive into the evolution of Cajal-Retzius cells! If you are interested in cell type evolution and cerebral cortex evo-devo, please read on… www.biorxiv.org/content/10.1... 🧵 1/7

Evolution of Cajal-Retzius Cells in Vertebrates from an Ancient Class of Tp73+ Neurons

In the developing cerebral cortex, Cajal Retzius (CR) cells are early-born neurons that orchestrate the development of mammalian-specific cortical features. However, this cell type has not been conclu...

www.biorxiv.org

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Giacomo Gattoni @giacomogattoni.bsky.social · Aug 12

Congratulations Jan, amazing news!! 🥳

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Giacomo Gattoni @giacomogattoni.bsky.social · Jun 28

That’s amazing Laurent, congratulations!! 🎉 🎉

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Giacomo Gattoni @giacomogattoni.bsky.social · Apr 26

Thank you so much Claire!! and thank you for suggesting this, I have been wanting to get into Mastodon for a while now, this was the perfect opportunity 😄

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Giacomo Gattoni @giacomogattoni.bsky.social · Apr 25

Thank you so much!! 😄

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Giacomo Gattoni @giacomogattoni.bsky.social · Apr 25

Thank you so much Bianca!! 😄

Giacomo Gattoni @giacomogattoni.bsky.social · Apr 25

Buon 25 Aprile!

On this day we celebrate the efforts and victory of the Italian resistance movement, and the liberation of Italy from fascism and from Nazi occupation! 🎉

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Giacomo Gattoni @giacomogattoni.bsky.social · Apr 24

And I can't deny that I was also very happy to put so many phylogenetic trees in this paper! 😂🌳

Thanks to @amphispacelab.bsky.social, @labonnelab.bsky.social, @camzoology.bsky.social and to the Whitten Programme for funding my PhD.

And thank you for reading! Let me know if you have questions! 😄

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Giacomo Gattoni @giacomogattoni.bsky.social · Apr 24

I feel incredibly lucky as this started out as a panicked side-project in Covid times, and became such a wonderfully collaborative work, it made me feel so happy about being in science! 👨‍🔬 So, huge thanks to all the authors that helped putting together this evolutionary story! 🫶

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Giacomo Gattoni @giacomogattoni.bsky.social · Apr 24

We further propose that the early duplication of FoxQ2a and FoxQ2b, along with their redundant functions, provided the ideal background for subfunctionalization, contributing to the fast evolutionary rate of FoxQ2 sequences observed in bilaterians. 🧬

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Giacomo Gattoni @giacomogattoni.bsky.social · Apr 24

This work clarifies the complex evolutionary history of FoxQ2 genes, identifying two ancient paralogs (FoxQ2a+b and FoxQ2c) expressed in distinct embryonic domains, and a more recent duplication of FoxQ2a and FoxQ2b. We also find a richer repertoire of vertebrate Fox genes than previously thought.

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Giacomo Gattoni @giacomogattoni.bsky.social · Apr 24

Finally, we compared FoxQ2 upstream region across 5 amphioxus species to detect conserved regulatory regions and predict transcription factor binding with developmental-timing and cell-type specificity, suggesting a similar FoxQ2a regulation in deuterostomes in line with functional conservation. 🧬

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Giacomo Gattoni @giacomogattoni.bsky.social · Apr 24

We then studied the expression of these paralogs in a variety of chordates: FoxQ2a is found in the amphioxus anterior ectoderm and in retina photoreceptors of zebrafish and chick. 👁️ The real surprise was the mysterious FoxQ2c, which we found expressed in the endoderm of amphioxus, lamprey and skate!

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Giacomo Gattoni @giacomogattoni.bsky.social · Apr 24

Moreover, the analysis showed that, contrary to what previously thought, vertebrates possess two ancestral FoxQ2 genes. 🤩 Bony fishes have only FoxQ2a while lampreys, skates and sharks have FoxQ2c. 🦈 On the other hand, amphioxus is one of the few animals with all three paralogs!

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Giacomo Gattoni @giacomogattoni.bsky.social · Apr 24

These revealed the presence of three ancient FoxQ2 genes! FoxQ2a and FoxQ2b were described previously, and we found a third branch called FoxQ2c. FoxQ2a+b and FoxQ2c types separated already near the root of the animal tree, while FoxQ2b duplicated from FoxQ2a in the cnidarian-bilaterian ancestor.

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Giacomo Gattoni @giacomogattoni.bsky.social · Apr 24

To answer these questions and explain the counterintuitive conserved expression of divergent genes, here we have performed #phylogenetic and #synteny analyses of FoxQ2 #genes from 21 animal phyla. 🧬

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Giacomo Gattoni @giacomogattoni.bsky.social · Apr 24

At the same time, previous analyses have suggested an unclear and convoluted evolutionary history of FoxQ2 genes, with multiple taxon-specific duplications and losses. Was there a single ancestral FoxQ2 gene? And if so, when and how did it duplicate during animal evolution? 🤔

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Giacomo Gattoni @giacomogattoni.bsky.social · Apr 24

FoxQ2 genes were first discovered by studying #amphioxus, but they have since been found in at least 14 animal phyla. Different studies have shown their conserved anterior expression in the embryos of many animals, from jellyfish to flies, worms and sea urchins. 🪸🪱🪰⭐🐟

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Giacomo Gattoni @giacomogattoni.bsky.social · Apr 24

New preprint from my PhD in @amphispacelab.bsky.social is out! 🥳

We investigated the evolution of my favorite gene FoxQ2 across 21 animal phyla, and found three ancient paralogs with a very dynamic history.

More on phylogeny, synteny, and comparative in situs in the 🧵 below!

tinyurl.com/2j96px45

Evolutionary dynamics of FoxQ2 transcription factors across metazoans: A tale of three ancient paralogs

FoxQ2 is a highly conserved class of Forkhead-box transcription factors expressed on the anterior side of the body in cnidarians and bilaterians. Despite this conserved expression pattern, recent phyl...

tinyurl.com

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Giacomo Gattoni @giacomogattoni.bsky.social · Apr 24

And I can't deny that I was also very happy to fill this paper with phylogenetic trees! 😂🌳

Thanks to @amphispacelab.bsky.social, @labonnelab.bsky.social, @camzoology.bsky.social and the Whitten Program for funding my PhD.

And thank you for reading! Let me know if you have any question 😄

Giacomo Gattoni @giacomogattoni.bsky.social · Apr 24

I feel incredibly lucky as this started out as a panicked side-project in Covid times, and became such a wonderfully collaborative work, it made me feel so happy about being in #science! 👨‍🔬 So, huge thanks to all the authors that helped putting together this evolutionary story! 🫶

1

Giacomo Gattoni @giacomogattoni.bsky.social · Apr 24

We further propose that the early duplication of FoxQ2a and FoxQ2b, along with their redundant functions, provided the ideal background for subfunctionalization, contributing to the fast evolutionary rate of FoxQ2 sequences observed in bilaterians.

1

Giacomo Gattoni @giacomogattoni.bsky.social · Apr 24

This work clarifies the complex evolutionary history of FoxQ2 genes, identifying two ancient paralogs (FoxQ2a+b and FoxQ2c) expressed in distinct embryonic domains, and a more recent duplication of FoxQ2a and FoxQ2b. We also find a richer repertoire of vertebrate Fox genes than previously thought 🧬

1

Giacomo Gattoni @giacomogattoni.bsky.social · Apr 24

Finally, we compared FoxQ2 upstream region across 5 amphioxus species to detect conserved regulatory regions and predict transcription factor binding with developmental-timing and cell-type specificity, suggesting a similar FoxQ2a regulation in deuterostomes in line with functional conservation.

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