[March. 30] 138th IRCMS Seminar

March 24 2026

We would like to inform you that the 138th IRCMS seminar has been scheduled as below.
* This IRCMS seminar is open to everyone.

Date      : March 30, 2026 (Monday)

Time      : 14:00-15:00

ZOOM　: Meeting ID: 986 8009 6010

　　　　  Passcode:  Sem30Mar

Speaker : Dr. Rita Aires (Dresden University of Technology, Germany)

Title        : Tissue composition shapes differential skeletal integration strategies during axolotl limb regeneration

Abstract:

Limb regeneration requires not only rebuilding the missing structures, but also integrating them with the stump tissues. Osteoclast-mediated tissue resorption is essential for skeletal integration during regeneration. However, given the cellular and structural heterogeneity along the limb skeleton, it is unknown if skeletal tissue composition impacts resorption and, if so, how it is regulated.

Here, we show that osteoclast-mediated skeletal resorption is primarily activated in amputations damaging calcified regions of the skeleton, but not in cartilaginous areas. Using a combination of spatial transcriptomics and bulk RNA sequencing, we found that amputations in calcified regions trigger the sustained expression of RANKL and the chemokine Loc138491483/Ccl24-like. We also demonstrate that Loc138491483/Ccl24-like is sufficient to induce osteoclast presence in non-resorbing amputations. Finally, our data suggests that the transcriptomic profile of the apical ectodermal cap is modified according to the underlying tissue types injured by the amputation.

Overall, our work reveals that tissue composition at the amputation plane directs important adaptations of the regenerative program to the damaged tissues, particularly regarding integration strategies. These context-dependent responses will ultimately contribute to the near-seamless tissue integration of the regenerating axolotl limb regardless of the amputation position.

Major papers:

1. Kramer, J. and Aires, R., Keeley, S. D., Schröder, T. A., Lauer, G. and Sandoval-Guzmán,

T. (2024). Axolotl mandible regeneration occurs through mechanical gap closure and a shared regenerative program with the limb. Dis. Model Mech. doi: 10.1242/dmm.050743.

2. Zhong, J. and Aires, R., Tsissios, G., Skoufa, E., Brandt, K., Sandoval-Guzmán, T. and Aztekin, C. (2023). Multi-species atlas resolves an axolotl limb development and regeneration paradox. Nat. Commun. 14, 6346. doi: 10.1038/s41467-023-41944-w.

3. Aires, R., de Lemos, L., Nóvoa, A., Jurberg, A. D., Mascrez, B., Duboule, D. and Mallo, M. (2019) Tail Bud Progenitor Activity Relies on a Network Comprising Gdf11, Lin28, and Hox13 Genes. Dev. Cell 48, 1-13; doi: 10.1016/j.devcel.2018.12.004.