Dendrite regeneration in the vertebrate spinal cord

Axon regeneration in response to injury has been documented in many animals over several hundred years. In contrast, how neurons respond to dendrite injury has been examined only in the last decade. So far, dendrite regeneration after injury has been documented in invertebrate model systems, but has not been assayed in a vertebrate. In this study, we use zebrafish motor neurons to track neurons after dendrite injury. We address two major gaps in our knowledge of dendrite regeneration: 1) whether post-synaptic dendrites can regenerate and 2) whether vertebrate dendrites can regenerate. We find that motor neurons survive laser microsurgery to remove one or all dendrites. Outgrowth of new dendrites typically initiated one to three days after injury, and a new, stable dendrite arbor was in place by five days after injury. We conclude that zebrafish motor neurons have the capacity to regenerate a new dendrite arbor.

Automated summary

Axon regeneration after injury has been studied for many animals over centuries, while the response of neurons to dendrite injury has only been investigated in the past decade. Although dendrite regeneration has been observed in invertebrate model systems, it has not been examined in vertebrates. This study used zebrafish motor neurons to examine dendrite regeneration, addressing two gaps in our knowledge: whether post-synaptic dendrites can regenerate and whether vertebrate dendrites can regenerate. The findings demonstrate that zebrafish motor neurons have the ability to regenerate a new dendrite arbor.