![Inhibition of PS-dependent spine pruning by MFG-E8D89Eincreases the synaptic density in adult-born mature neurons in the OB. (A) Experimental scheme. (B) Total protrusion density of granule and periglomerular cells in Dcx-CreERT2; R26-tdTomato (Ctrl), Dcx-CreERT2; R26-EPT; R26-tdTomato (EPT), and Dcx-CreERT2; R26-D89E; R26-tdTomato (D89E) mice at 28 and 56 dpi (Ctrl, n = 4 [28 dpi] and 3 [56 dpi] mice; EPT, n = 3 [28 dpi] and 4 [56 dpi] mice; D89E, n = 3 mice [28 and 56 dpi]) (Granule cells, Ctrl, 28 dpi versus 56 dpi, t(151) = 5.6, P = 9.2 × 10−8, unpaired t test; EPT, 28 dpi versus 56 dpi, t(129) = 6.0, P = 1.7 × 10−8, unpaired t test; 56 dpi, x2(2) = 10.7, P = 0.0048, Ctrl versus D89E, P = 0.015, EPT versus D89E, P = 0.013, Steel-Dwass test; periglomerular cells, Ctrl, 28 dpi versus 56 dpi, t(82) = 11.4, P = 2.2 × 10−16, unpaired t test; EPT, 28 dpi versus 56 dpi, t(58) = 5.0, P = 5.8 × 10−6, unpaired t test; D89E, 28 dpi versus 56 dpi, t(59) = 2.0, P = 0.045, unpaired t test; 56 dpi, x2(2) = 11.7, P = 0.0029, Ctrl versus D89E, P = 0.0023, EPT versus D89E, P = 0.032, Steel-Dwass test). Data are pooled from eight independent experiments. (C) Representative image of tdTomato+ granule cells of adult Dcx-CreERT2; R26-tdTomato mice at 56 dpi (n = 3 mice) stained for DsRed (white). Dendrites of granule cells are divided into four subregions: apical, distal, proximal, and basal. (D–F) Effect of MFG-E8D89E on the spine density of granule cells in the OB. Density (D [Proximal, P = 0.012, Welch’s t test; Apical, t(88) = −2.9, P = 0.0051, unpaired t test], E [Apical, P = 0.011, Welch’s t test]) and representative images (F) of protrusions (D) and mushroom spines (E) in the granule cells in EPT (n = 4 mice) and D89E (n = 3 mice) mice 56 dpi are shown. Asterisks and arrows indicate mushroom spines and other protrusions, respectively (F). Data are pooled from four independent experiments. Parentheses in B, D, and E indicate the number of analyzed cells. GCL, granule cell layer; MCL, mitral cell layer; EPL, external plexiform layer; GL, glomerular layer. Scale bars: C, 50 µm; F, 2 µm. *, P < 0.05; **, P < 0.01; ***, P < 0.005. Data shown are mean ± SEM.](https://cdn.rupress.org/rup/content_public/journal/jem/219/4/10.1084_jem.20202304/5/jem_20202304_fig7.png?Expires=1771037696&Signature=TLZmNe4Q3ssFQfz9GYBgwls5e1cZCql-TlFg65SK45Cp8~MG0qVvhVT-JQ7RjQ85ncHTtpXQVYrjMWDojPwB-K8Dy7YuGDu~AGU4laX1v5rCMkbQhCoC9vR4Nt1RefLOZvWANjNawMgE0BgAKExVnmDK3~jvU99H0n0zzr514biaKflt-IiN4ZUDR8MlLkf~MIFgtFHZKlRnuPlmZgrGMYyxuTkPOcbgsYNnosH4Vs8jZWJRPTi3ZJotKb~fQ4eEXu3sIn4JVYYo9hadYpBLlSdsr29xrc4f6f4oHPV1PMI9ErHW9RUwsAtA6q4hRiuFDEbAchPlmsyav7KhlLUsoA__&Key-Pair-Id=APKAIE5G5CRDK6RD3PGA)
Inhibition of PS-dependent spine pruning by MFG-E8 D89E increases the synaptic density in adult-born mature neurons in the OB. (A) Experimental scheme. (B) Total protrusion density of granule and periglomerular cells in Dcx-CreERT2; R26-tdTomato (Ctrl), Dcx-CreERT2; R26-EPT; R26-tdTomato (EPT), and Dcx-CreERT2; R26-D89E; R26-tdTomato (D89E) mice at 28 and 56 dpi (Ctrl, n = 4 [28 dpi] and 3 [56 dpi] mice; EPT, n = 3 [28 dpi] and 4 [56 dpi] mice; D89E, n = 3 mice [28 and 56 dpi]) (Granule cells, Ctrl, 28 dpi versus 56 dpi, t(151) = 5.6, P = 9.2 × 10−8, unpaired t test; EPT, 28 dpi versus 56 dpi, t(129) = 6.0, P = 1.7 × 10−8, unpaired t test; 56 dpi, x2(2) = 10.7, P = 0.0048, Ctrl versus D89E, P = 0.015, EPT versus D89E, P = 0.013, Steel-Dwass test; periglomerular cells, Ctrl, 28 dpi versus 56 dpi, t(82) = 11.4, P = 2.2 × 10−16, unpaired t test; EPT, 28 dpi versus 56 dpi, t(58) = 5.0, P = 5.8 × 10−6, unpaired t test; D89E, 28 dpi versus 56 dpi, t(59) = 2.0, P = 0.045, unpaired t test; 56 dpi, x2(2) = 11.7, P = 0.0029, Ctrl versus D89E, P = 0.0023, EPT versus D89E, P = 0.032, Steel-Dwass test). Data are pooled from eight independent experiments. (C) Representative image of tdTomato+ granule cells of adult Dcx-CreERT2; R26-tdTomato mice at 56 dpi (n = 3 mice) stained for DsRed (white). Dendrites of granule cells are divided into four subregions: apical, distal, proximal, and basal. (D–F) Effect of MFG-E8D89E on the spine density of granule cells in the OB. Density (D [Proximal, P = 0.012, Welch’s t test; Apical, t(88) = −2.9, P = 0.0051, unpaired t test], E [Apical, P = 0.011, Welch’s t test]) and representative images (F) of protrusions (D) and mushroom spines (E) in the granule cells in EPT (n = 4 mice) and D89E (n = 3 mice) mice 56 dpi are shown. Asterisks and arrows indicate mushroom spines and other protrusions, respectively (F). Data are pooled from four independent experiments. Parentheses in B, D, and E indicate the number of analyzed cells. GCL, granule cell layer; MCL, mitral cell layer; EPL, external plexiform layer; GL, glomerular layer. Scale bars: C, 50 µm; F, 2 µm. *, P < 0.05; **, P < 0.01; ***, P < 0.005. Data shown are mean ± SEM.
