Figure 10.

Induction of a PRAS40-mTOR pathway by PTEN deletion in injured MNs. A₁-A₅, In unlesioned Ctr. MNs, no P-PRAS40 was visible (A₁) in contrast to 3 dpi (A₃). In KO neurons, P-PRAS40 abundance was higher in FMNs before (A₂) and after injury (A₄; quantified in A_5; n = 5 for each bar). B₁-B₅, Total mTOR abundance was not affected by genotype or injury status at 3 dpi (quantified in B_5; n = 5 for each bar). C₁-C₅, P-mTOR levels were slightly upregulated in injured Ctr. neurons (C₃) at 3 dpi. After PTEN ablation, P-mTOR expression was elevated before (C₂) and after injury (C₄; quantified in C_5; n = 5, 4, 5, 4 for each bar, respectively). Insets, P-mTOR localization on neuronal protrusions. C₅, Black dots in gray bars indicate Pten homozygous WT mice. Red dots indicate heterozygous mice. D₁-D₅, At 3 dpi, total 4EBP1 abundance was higher in Ctr. (D₃) compared with injured KO (D₄) MNs (quantified in D_5; n = 4 for each bar). E₁-E₅, P-4EBP1 levels were upregulated in injured Ctr. (E₃) and KO (E₄) neurons compared with the uninjured side (E₁,E₂) at 3 dpi. The number of strongly positive P-4EBP1 MNs was higher in Ctr. compared with injured KO MNs (quantified in E_5; n = 4 for each bar). F₁-F₅, P-S6 levels were similar in unlesioned and lesioned Ctr. and KO neurons (quantified in F_5; n = 5 for each bar). G₁-G₅, At 22 dpi, total 4EBP1 levels were elevated after FN injury in Ctr. MNs (G₁,G₃). In PTEN-deficient animals, 4EBP1 levels were higher both on the unlesioned (G₂) and injured (G₄) side (quantified in G₅; n = 4, 5, 4, 5 for each bar, respectively). H₁-H₅, At 22 dpi, highest P-4EBP1 levels were quantified in KO animals after injury (H₄). In contrast, in all other conditions (H₁-H₃), only weak P-4EBP1 levels were measured (H₅; n = 4, 5, 4, 5 for each bar, respectively). A₅, B₅, C₅, F₅, G₅, H₅, Each dot indicates 1 animal. Data are mean ± SD. *p < 0.05; **p < 0.01; ***p < 0.001; two-sided Mann–Whitney test. Scale bars: A-H, 200 µm.