title: Reconstruction of dopaminergic neural network and locomotion function in planarian regenerates.
abstract: 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.
authors.affiliation: Department of Neurobiology, 21st Century COE Program, Kyoto Pharmaceutical University, Kyoto 607-8414, Japan.
authors.forename: Kaneyasu
authors.initials: K
authors.lastname: Nishimura
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Kitamura
authors.forename: Takeshi
authors.initials: T
authors.lastname: Inoue
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Umesono
authors.forename: Shozo
authors.initials: S
authors.lastname: Sano
authors.forename: Kanji
authors.initials: K
authors.lastname: Yoshimoto
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Inden
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Takata
authors.forename: Takashi
authors.initials: T
authors.lastname: Taniguchi
authors.forename: Shun
authors.initials: S
authors.lastname: Shimohama
authors.forename: Kiyokazu
authors.initials: K
authors.lastname: Agata
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D017124:Conserved Sequence; D004296:Dopa Decarboxylase / Q000235:genetics; D004298:Dopamine / Q000502:physiology*; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D009043:Motor Activity / Q000502:physiology*; D009415:Nerve Net / Q000502:physiology*; D009416:Nerve Regeneration / Q000502:physiology*; D009424:Nervous System Physiological Phenomena; D010932:Planarians / Q000201:enzymology / Q000502:physiology*; D016133:Polymerase Chain Reaction; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D012701:Serotonin / Q000378:metabolism; D014446:Tyrosine 3-Monooxygenase / Q000235:genetics*
chemical_list: D012701:Serotonin; D014446:Tyrosine 3-Monooxygenase; D004296:Dopa Decarboxylase; D004298:Dopamine