Ana Martínez Gómez

Before there’s a heartbeat, there’s this little glowing heart in the neural tube 💕 Chicken neural crest cells in magenta. 📸Image by Rocío Márquez, Strobl-Mazzulla Lab @pstrobl.bsky.social #FluorescentFriday #SciValentine

You can find the full developmental stage series on Xenbase here 👇

www.xenbase.org/xenbase/anat...

At this stage, the embryos are actively feeding, with a fully developed heart.

✨ Day 7 post-fertilization — embryos are around stage 46.

🐸⭐ Follow the development of Xenopus laevis embryos with me!

Read below 👇

#Xenopus #EvoDevo #DevBio #Science #Neuroscience

New to using Jupyter notebooks for the Allen Brain Cell Atlas?

Join us on Feb. 11 for a beginner-friendly webinar focusing on installation, set-up, and common questions.

Register for the meeting link and recording: https://alleninstitute-org.zoom.us/webinar/register/WN_q0sJzndpRbSZWjrSGblu6A#/

You can find the full developmental stage series on Xenbase here 👇

www.xenbase.org/xenbase/anat...

✨ Day 5 post-fertilization — embryos are around stages 39-40.

🐸⭐ Follow the development of Xenopus laevis embryos with me!

Read below 👇

#Xenopus #EvoDevo #DevBio #Science #Neuroscience

You can find the full developmental stage series on Xenbase here 👇

www.xenbase.org/xenbase/anat...

Some embryos show altered development.

✨ Day 4 post-fertilization — embryos are around stages 37/38.
Obvious heartbeats 💓, visible blood flow, melanophores along the tail 🐸.

🐸⭐ Follow the development of Xenopus laevis embryos with me!

Read below 👇

#Xenopus #EvoDevo #DevBio #Science #Neuroscience

You can find the full developmental stage series on Xenbase here 👇

www.xenbase.org/xenbase/anat...

✨ Day 3 post-fertilization — embryos are around stages 25–26 and start showing their first movements.

🐸⭐ Follow the development of Xenopus laevis embryos with me!

Read below 👇

#Xenopus #EvoDevo #DevBio #Science #Neuroscience

You can find the full developmental stage series on Xenbase here 👇

www.xenbase.org/xenbase/anat...

However, embryonic development is not fully synchronized—some embryos can still be observed at blastula stages.

✨ Day 2 post-fertilization: embryos are around stages 17–18.

🐸⭐ Follow the development of Xenopus laevis embryos with me!

Read below 👇

#Xenopus #EvoDevo #DevBio #Science #Neuroscience

Fig. 1. IGF2 and Cerberus mRNAs cooperate in ectopic head induction in Xenopus embryos. Embryos were microinjected into the ventral marginal zone of a single blastomere at the 4- to 8-cell stage. (A) Uninjected control sibling at early tailbud stage (n = 81). (B) A single ventral injection of IGF2 mRNA caused a small ectopic head protrusion with a pigmented cement gland on the belly (n = 86, 68 % with ectopic structures). (C) Cerberus mRNA induced a secondary head-like structure (n = 78, 94 % with ectopic heads). (D) Co-injection of IGF2 and Cerberus mRNAs induced a large ectopic head with an expanded cement gland (n = 90, 98 % with ectopic heads). (E–H) Panoramic views of control and injected embryos. Injected mRNA doses per embryo were: Cerberus, 100 pg; IGF2, 2 ng. Results from two experiments. Scale bars are 500 μm (A-D) and 2 mm (E-H).

Fig. 6. Dominant-negative IGF receptor 1 blocked ectopic head formation by Cerberus mRNA in single ventral injections. (A) Control embryo at stage 24 injected with LacZ (100 pg) mRNA but not stained for β-galactosidase (n = 50). (B) DN-IGFR (600 pg) and LacZ injected embryos (n = 20, all normal). (C) Cerberus (100 pg) injected embryos with ectopic heads (n = 56, 96 % ectopic heads). (D) DN-IGFR blocked Cerberus ectopic heads (n = 33, 88 % with no ectopic structures, 12 % with small cement glands). (E–F) LacZ staining for (A–D). Scale bar, 500 μm.

A very curious paper from the De Robertis lab shows how Cerberus - a growth factor that inhibits Wnt signalling, and IGF - a growth factor that activates MAPK signalling, can synergistically induce a new head (aka ectopic archencephalic differentiation) in Xenopus embryos.
doi.org/10.1016/j.cd...

🚨🌿 Not everything in nature is perfect.

I’ll be documenting a recent Xenopus laevis egg laying and following the embryos through their developmental stages.

✨ Beginning with day 1 after fertilization: the very first hours of Xenopus laevis development.

From the cleavage stage through blastula and early gastrula stages.

🐸⭐ Follow the development of Xenopus laevis embryos with me!

Read below 👇

#Xenopus #EvoDevo #DevBio #Science #Neuroscience

First #MicroscopyMonday of 2026 deserves some festive cells.

Merry Christmas & Happy New Year !! ✨🎄

In my family, Christmas means handmade canelons.

Bones festes!

Vote for your favourite 'Featured image' from 2025 - FocalPlane Vote for your favourite 'Featured image' from 2025 - News

We’ve highlighted some wonderful images and researchers in our ‘Featured image’ series in 2025. To celebrate, we’re inviting you to vote for your favourite in our image competition!
#FluorescenceFriday
Check them out here: focalplane.biologists.com/2025/12/19/v...

#SnapshotsinNeuroscience | Featured on the #eNeuro blog from Lustig et al., a whole mount view of a young mouse brain with all cortical layer 5 neurons expressing dystonia-related gene Klhl14, highlighted in green.
Photo Credit: Alexander Lammers
https://blog.eneuro.org/2025/11/snapshots_klhl14_gene

Modelling co-development between the somites and neural tube in human trunk-like structures - Nature Cell Biology Makwana, Tilley et al. generate human stem cell-based trunk-like structures approximating Carnegie stage 13–14 of development. They use them to model and study the development of the thoracic and lumbar trunk.

Lovely little pre-Christmas present to see this out @natcellbio.nature.com! Some 🔥 new results in here since the biorvix incl (1) a new RARE-GFP reporter ✳️🙌, (2) additional NMP quantification 🔢, (3) no neural tube patterning on RA inhibition 🙅 etc. Enjoy! 😍 www.nature.com/articles/s41...

Bibliography:

📖 Numbers correspond to the citations in the original paper. Full references omitted for brevity.