26774784

PMC4864152

Postembryonic neurogenesis has been observed in several regions of the vertebrate brain, including the dentate gyrus and rostral migratory stream in mammals, and is required for normal behavior [1-3]. Recently, the hypothalamus has also been shown to undergo continuous neurogenesis as a way to mediate energy balance [4-10]. As the hypothalamus regulates multiple functional outputs, it is likely that additional behaviors may be affected by postembryonic neurogenesis in this brain structure. Here, we have identified a progenitor population in the zebrafish hypothalamus that continuously generates neurons that express tyrosine hydroxylase 2 (th2). We develop and use novel transgenic tools to characterize the lineage of th2(+) cells and demonstrate that they are dopaminergic. Through genetic ablation and optogenetic activation, we then show that th2(+) neurons modulate the initiation of swimming behavior in zebrafish larvae. Finally, we find that the generation of new th2(+) neurons following ablation correlates with restoration of normal behavior. This work thus identifies for the first time a population of dopaminergic neurons that regulates motor behavior capable of functional recovery.

CDC Public Access

DP2 MH100008/MH/NIMH NIH HHS/United States
T32 DC008553/DC/NIDCD NIH HHS/United States
DP2 MH100008/DP/NCCDPHP CDC HHS/United States
R01 NS082645/NS/NINDS NIH HHS/United States
5T32 HD07491/HD/NICHD NIH HHS/United States
T32 HD007491/HD/NICHD NIH HHS/United States
5T32 NS076067/NS/NINDS NIH HHS/United States
R01 NS053897/NS/NINDS NIH HHS/United States