Figure 6: Newborn RV-GFP-labeled GCs exhibit higher dendritic restructuring and dynamics compared with older AAV-Syn-labeled GCs.
(a) Time-lapse image sequence of a newborn cell on 8 consecutive days from 8–15 dpi. During this time frame, we observed a phase of high dynamics in structural rearrangement. While during the second week of development the cell exhibited considerable dendritic growth (white arrowheads), we also observed withdrawal of dendritic segments (red arrowheads), or complete branches. (b) Daily mean values of the total dendritic length (TDL) for RV-GFP-labeled GCs (green) and AAV-Syn-labeled GCs (red). (c) Mean TDL values grouped by week showed significant differences in RV-GFP-labeled GCs over time, i.e. between the second and the third week (two-way ANOVA with Bonferroni correction, P = 0.0016) as well as between the second and the fourth week (P < 0.0001). Moreover, the two cell populations displayed significant differences in the TDL during 8-14 dpi (two-way ANOVA with Bonferroni correction P = 0.0012) and 15–21 dpi (P = 0.0027). (d) To analyze dynamic changes in dendritic development, we calculated the average change in dendritic length per day and expressed the values as the percentage of the TDL of each previous day which was defined as 100%. Newborn GCs exhibited significant differences in TDL change between the first and the fourth week (two-way ANOVA with Bonferroni correction P < 0.0001) and between the third and the fourth week (P = 0.0053). (e) Newborn GCs displayed a significantly higher degree of change in TDL during 8–14 dpi (P = 0.0106) and 15–21 dpi (P = 0.0029) compared with older GCs. (c,e) 8–14 dpi: nRV-GFP = 17 (c), 12 (e), nAAV-Syn = 4; 15–21 dpi: nRV-GFP = 18, nAAV-Syn = 10; 22–28 dpi: nRV-GFP = 11, nAAV-Syn = 5. n represents number of cells (1–2 cells per culture). Error bars represent SEM. *P < 0.05. Scale bar: 10 μm.
