Figure 2. Embryonic dentate Hopx⁺ precursors give rise to granule neurons and adult RGLs in the dentate gyrus.

(A) Confocal images of Hopx/Nestin co-expression in developing dentate gyrus. Scale bars: 200 μm. DN: dentate neuroepithelium, CA: CA neuroepithelium, CC: cortical neuroepithelium, LGE: lateral ganglionic eminence, MGE: medial ganglionic eminence, LV: lateral ventricle.

(B) Confocal images of a clone at E11.5 consisting of two Nestin⁺ neural precursors in the DN (See Movie S1). Scale bar: 10 μm. Pregnant Hopx-CreER^T2::mTmG mice were given a single injection of tamoxifen to label embryos at E10.5 for clonal lineage-tracing analysis in (B-M). See Table S1.

(C) Confocal image of a clone at E15.5 consisting of cells in the DN and cells migrating along the dentate migratory stream into the dentate primordium. Scale bar: 50 μm.

(D) Confocal images of clone at E15.5 containing ventricular Hopx⁺ cells. Scale bars: 50 μm (top panel), 20 μm (bottom panel).

(E) 3D rendering of a reconstructed clone at E18.5 in which cells spanned from the DN through the dentate migratory stream to the dentate primordium (DG). Red dots represent individual labeled cells. Scale bar: 100 μm.

(F) Confocal image of a clone at E18.5 in which all progeny were located in the dentate primordium. Scale bar: 100 μm.

(G) Confocal images of a subset of a clone at E18.5 including a Hopx⁺ progenitor (Box 1) and a Prox1⁺ dentate granule neuron (Box 2). Arrowheads indicate GFP⁺ cell somas. Scale bars: 20 μm.

(H) Heat map of clonal progeny localization at E18.5. Each row represents a single clone.

(I) Confocal images of a clone at P8 consisting of RGLs and neuronal progeny in the dentate gyrus (left panel) with high magnification of the boxed area showing Nestin⁺ RGLs (right panel). Arrowheads indicate Nestin⁺ processes Scale bars: 20 μm.

(J) Quantification of clone composition at P8. N: neuronal cell; A: astrocytes. Values represent mean ± SEM (n = 4 clones).

(K) 3D rendering of a reconstructed clone at P30 spanning 20 sections (S1–S20; 45 μm in section thickness) depicts a single clone that includes neurons, astrocytes, and RGLs (higher magnification in Boxes 1 and 2). See Movie S2. Scale bar: 100 μm.

(L) Confocal images of section 11 of the clone reconstructed in (K) showing two Nestin⁺ RGLs (Boxes 1, 2). Scale bars: 100 μm (left panel) and 20 μm (right panel).

(M) Quantification of clone composition at P30. Values represent mean ± SEM (n = 3 clones). See also Figure S2, Table S1, and Movie S1 & 2.