TY - JOUR T1 - Hedgehog Signaling Regulates Neurogenesis in the Larval and Adult Zebrafish Hypothalamus JF - eneuro JO - eNeuro DO - 10.1523/ENEURO.0226-20.2020 VL - 7 IS - 6 SP - ENEURO.0226-20.2020 AU - Ira Male AU - A. Tuba Ozacar AU - Rita R. Fagan AU - Matthew D. Loring AU - Meng-Chieh Shen AU - Veronica A. Pace AU - Christine A. Devine AU - Grace E. Lawson AU - Alyssa Lutservitz AU - Rolf O. Karlstrom Y1 - 2020/11/01 UR - http://www.eneuro.org/content/7/6/ENEURO.0226-20.2020.abstract N2 - 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. ER -