Fig. 2.

TrkB is required for dendritic arborization in adult-born neurons. (A) Schematic diagram showing the experimental paradigm used for retrovirus injection into tamoxifen-induced TrkB^lox/lox-Cre R26R and control mice. Histograms show the total number of branches and the dendritic length of reporter-positive (βgal+) or -negative (βgal−) cells virally transduced with GFP (n = 20 neurons; 3 animals per genotype) (*, P < 0.05). (B) Graph depicts Sholl analysis of the dendritic arbors in the same neurons as in A (n = 20 neurons; 3 animals per genotype) (*, P < 0.05). (C) Representative confocal images depicting the dendritic morphology of reporter-positive (2–4; βgal+) or -negative (1; βgal−) cells transduced with GFP expressing retrovirus in TrkB^lox/lox-Cre R26R mice. Two-dimensional projection of tridimensional reconstruction of the cells is shown. (Scale bar, 10 μm.) (D) Schematic diagram showing the experimental paradigm. Graph depicts Sholl analysis of the dendritic arbor of cells single transduced (Cre or TrkB) or cotransduced (Cre/TrkB or Cre/TrkB FFF) with the retrovirus (n = 10; 3 animals for each experimental group) (*, P < 0.05). Representative confocal images of transduced cells are presented. Insets show the expression of the reporter marker GFP (green) and/or DsRed (red). (Scale bar, 20 μm.)