Figure 2.

Dendritic and axonal hypertrophy and ectopic axonal tracts in Pten mutants. A, Floating sections (50 μm) of brains from 4- and 7-month-old control and mutant mice were stained for Synapsin I (red) and Calbindin (green). Elongated mossy fiber tract from the granular layer of mutant dentate gyrus is shown in both 4- and 7-month-old mutant brains (arrows). An ectopic layer of axonal signals (arrowhead) in the inner molecular layer is observed in 7-month-old mutant brain. Scale bar, 500 μm. B, Quantification analysis shows that mutant mice have increased thickness of mossy fiber tract, as measured by the width of Synapsin I and Calbindin double-stained axons coming out of DG. n = 3 for control and mutant for 4-month-old mice; n = 6 for control and n = 5 for mutant for 7-month-old mice. C, DCX immunostaining of 2-month-old mutant brain shows hypertrophy and arborization of dendrites. Bottom, High-magnification images of the boxes in the top. Scale bar, 200 μm. Data are mean ± SEM; t test was used for all analyses. *p < 0.05, **p < 0.01.