%0 Journal Article %A Ira Male %A A. Tuba Ozacar %A Rita R. Fagan %A Matthew D. Loring %A Meng-Chieh Shen %A Veronica A. Pace %A Christine A. Devine %A Grace E. Lawson %A Alyssa Lutservitz %A Rolf O. Karlstrom %T Hedgehog Signaling Regulates Neurogenesis in the Larval and Adult Zebrafish Hypothalamus %D 2020 %R 10.1523/ENEURO.0226-20.2020 %J eneuro %P ENEURO.0226-20.2020 %V 7 %N 6 %X Neurogenesis is now known to play a role in adult hypothalamic function, yet the cell-cell mechanisms regulating this neurogenesis remain poorly understood. Here, we show that Hedgehog (Hh)/Gli signaling positively regulates hypothalamic neurogenesis in both larval and adult zebrafish and is necessary and sufficient for normal hypothalamic proliferation rates. Hh-responsive radial glia represent a relatively highly proliferative precursor population that gives rise to dopaminergic, serotonergic, and GABAergic neurons. In situ and transgenic reporter analyses revealed substantial heterogeneity in cell-cell signaling within the hypothalamic niche, with slow cycling Nestin-expressing cells residing among distinct and overlapping populations of Sonic Hh (Shh)-expressing, Hh-responsive, Notch-responsive, and Wnt-responsive radial glia. This work shows for the first time that Hh/Gli signaling is a key component of the complex cell-cell signaling environment that regulates hypothalamic neurogenesis throughout life. %U https://www.eneuro.org/content/eneuro/7/6/ENEURO.0226-20.2020.full.pdf