Supplementary Figure 1: Characterization of DREADD expression and induction in P42-Gi OB.

(a) Strategy to inhibit new neurons in P42-Gi mice via CNO administration followed by 90 minutes of survival, perfusion, and tissue processing for c-Fos analysis. (b) High-power confocal images of EGFP+ cells in a P42-Gi OB coexpressing HA or mCherry (red as indicated) following co-injection of AAV2-Gi tagged with either HA or mCherry and AAV2-pSYN::EGFP. Scale bar, 10 μm. (c) Percentages of AAV2 transduced cells in the OB double labeled for tagged markers (HA or mCherry) and EGFP as well as tag only and EGFP only cells. Data are mean ± s.e.m; n = 3 animals/group, 100 EGFP+ cells/animal. (d) Low power confocal image of a sagittal forebrain section of a P42-Gi mouse (blue, DAPI). EGFP expression was confined to a subset of neurons in the OB (Inset: EGFP⁺ and NeuN⁺ (red) neurons). Scale bar, 100 μm; Inset scale bar, 10 μm. (e) The pSYN promoter in AAV2-Gi vectors prevents expression in the SEZ or RMS (No EGFP⁺ cells in Dcx+ domains, red; DAPI, blue; V, ventricle). Scale bar, 25 μm. (f) High-power confocal images of a P42-Gi OB section containing EGFP⁺ neurons coimmunostained for c-Fos (i; Scale bar, 50 μm); layers of the OB: granule cell layer (GCL), external plexiform layer (EPL), periglomerular layer (PGL). Representative EGFP⁺ granule neurons with dendrites arborizing in the EPL (ii). Blanes- and Golgi-like neurons in the deep layers of the GCL (iii). Scale bars in ii and iii, 25 μm.