The axolotl (Ambystoma mexicanum) is widely known for its incredible regenerative abilities: Upon injury, the axolotl can fully regrow several body parts including its tail. However, for the regrown tail to become functional, the nerves that control their movement also need to regrow and establish a network that controls muscle activity. The details of how neurons re-enter the regenerating structure, re-connect and re-establish function were, so far, unknown.
In her project, Carina Seidl will explore neuronal regeneration from the cellular to the functional level. First, she will track which types of neurons populate the regenerated areas of the axolotl tail, and how they do so. Seidl will use modern light sheet imaging techniques that take advantage of the axolotl’s transparent skin to trace the growth and connectivity of fluorescently labeled neurons in the regenerating tail.
To understand how neurons can restore functionality of the injured tail, Seidl will study the swimming ability and behavioral responses of the recovering axolotl. “I will use neural-network-based behavioral tracking to analyze the axolotl’s reaction speed and swimming movement with and without injury. For example, I will touch the regenerated tail and see how fast the axolotl responds to that stimulus by swimming away.”
Ultimately, the project will demonstrate how accurate the regeneration of the nervous system is, from sensory input, to activity, to motion, and where accuracy is required to restore functionality. Unraveling these basic mechanisms may contribute to developing novel treatments that increase functional recovery after spinal injuries.
During her PhD in Molecular Embryology at the German Cancer Research Center in Heidelberg, Seidl studied the role of signaling pathways during embryonic development and motile cilia formation in the frogs Xenopus laevis and Xenopus tropicalis. In August of 2023, Seidl joined the lab of Elly Tanaka, previously at the Research Institute of Molecular Pathology (IMP) and now at IMBA, as a postdoctoral researcher.
“I’m grateful for the support by the Peter and Traudl Engelhorn Foundation, which highlights the relevance of my project, and am excited about the opportunity to develop an independent research profile,” Seidl says. “This funding will allow me to develop an exciting research project and network with other awardees.”