Illuminating brain circuits in the axolotl

The axolotl is a powerful model for understanding regeneration, however, studying the axolotl’s nervous system has been challenging as tools for visualizing and manipulating neuronal circuits have been lacking. In a study published in PNAS, Katharina Lust and Elly Tanaka at IMBA now present a method for introducing genes into axolotl neurons, allowing scientists to interrogate neuronal organization in the axolotl.

The axolotl’s (Ambystoma mexicanum) extraordinary regenerative abilities—the salamander can regrow lost limbs and repair complex organs, including the retina and the brain – make the axolotl an ideal model for studying both how neural circuits form and how they regenerate after injury. So far, brain regeneration in the axolotl has been studied with classical methods, such as by employing tracers and antibodies. However, researchers have lacked the tools for capturing the dynamics of circuit regeneration, interrogating functional recovery and manipulating neuronal function in the axolotl brain.

Now, Katharina Lust and Elly Tanaka at the Institute of Molecular Biotechnology (IMBA) of the Austrian Academy of Sciences present an efficient method for delivering genes into axolotl neurons using viruses, enabling researchers to dynamically visualize neurons and transfer novel genes into neurons. Their findings were published in PNAS on March 5th.