Reconstruction of dopaminergic neural network and locomotion function in planarian regenerates
Article first published online: 6 MAR 2007
Copyright © 2007 Wiley Periodicals, Inc.
Volume 67, Issue 8, pages 1059–1078, July 2007
How to Cite
Nishimura, K., Kitamura, Y., Inoue, T., Umesono, Y., Sano, S., Yoshimoto, K., Inden, M., Takata, K., Taniguchi, T., Shimohama, S. and Agata, K. (2007), Reconstruction of dopaminergic neural network and locomotion function in planarian regenerates. Devel Neurobio, 67: 1059–1078. doi: 10.1002/dneu.20377
- Issue published online: 12 JUN 2007
- Article first published online: 6 MAR 2007
- Manuscript Accepted: 8 DEC 2006
- Manuscript Revised: 16 NOV 2006
- Manuscript Received: 1 SEP 2006
- Japanese MEXT
- dopaminergic neurons;
- neural network;
- RNA interference
Planarian, an invertebrate flatworm, has a high capacity for regeneration when compared with other worms and animals. We show here for the first time that the reconstructed dopamine (DA) neural network regulates locomotion and behavior in planarian regenerates. The gene encoding tyrosine hydroxylase in the planarian Dugesia japonica (DjTH) was identified. DjTH protein was coexpressed with aromatic amino acid decarboxylase-like A (DjAADCA) in the planarian central nervous system (CNS). In addition, DjTH-knockdown planarians lost the ability to synthesize DA, but showed no change in 5-hydroxytryptamine synthesis. When the planarian body was amputated, DjTH-positive neurons were regenerated in the brain newly rebuilt from the tail piece at Day 3, and the DjTH-positive axonal and dendritic neural network in the CNS (dopaminergic tiara) was reconstructed at Days 5–7. At that time, autonomic locomotion and methamphetamine-induced hyperkinesia were also suppressed in DjTH-knockdown planarians. Planarian locomotion and behavior seem to be regulated in both cilia- and muscle-dependent manners. In DjTH-knockdown planarians, muscle-mediated locomotion and behavior were significantly attenuated. These results suggest that DA neurons play a key role in the muscle-mediated movement in planarians. © 2007 Wiley Periodicals, Inc. Develop Neurobiol, 2007.