Figure 2. Brain-wide mapping of early postnatally developing GABAergic neurons.

a, Overview of cell type mapping pipeline b, 3D renderings of Gad2 cell density (cells/mm³) registered to age-matched epDevAtlas. Each processed image per age is from a representative Gad2-IRES-Cre;Ai14 brain sample. c, Gad2 cell type growth chart across early postnatal mouse brain development, emphasizing major brain regions based on the anatomical hierarchy of Allen CCFv3. d-e, Olfactory areas show different trajectories of Gad2 cell density, creating a distinction between the olfactory bulb and olfactory cortices. (d) Representative STPT images of Gad2 cells and (e) their average density in the olfactory brain regions including main olfactory bulb (MOB), accessory olfactory bulb (AOB), anterior olfactory nucleus (AON), and piriform cortex (PIR) between P4 and 14. f-g, Striatal GABAergic cells display increased Gad2 expression from P4 to P14. (f) Representative STPT images of Gad2 cells and (g) their density in the caudoputamen (CP), with striosomes (green arrow) exhibiting earlier maturation, and nucleus accumbens (ACB). h-i, Hippocampal brain regions exhibit decreased Gad2 expression from P4 to P14. (h) Representative STPT images and (i) density of Gad2 cells in the hippocampal formation (HPF) and isocortex. All data in Fig. 2e, 2g, and 2i are reported as mean ± s.d. (includes shaded areas between error bars). See Extended Data Table 3 for Gad2 cell counts, density, volume measurements, and abbreviations.