Fig. 4: sALS patient-derived motor neurons show increased p53–mediated DNA damage, and p53 knockdown restores SIRT1 expression and alleviates neurodegeneration.
From: The Ku80-p53-SIRT1 axis in DNA damage response contributes to sporadic and familial ALS and FTD
Western blot analysis (a) and quantification of total p53 (b), phosphorylated p53 (p-p53) (c), phosphorylated H2AX (γH2AX) (d), and Ku80 (e) protein levels in 3-month-old sALS iMNs. Data are presented as mean ± SEM from four biologically independent differentiation experiments per iPSC line, using four control and four sALS iPSC lines (iMNs-1/2/3/4). Statistical comparisons between the two groups (control in black, sALS in red) were performed using an unpaired two-tailed t test (n = 4 lines per group). f Time-course analysis of neuronal viability using LDH release assay in sALS iMNs. Neurons were differentiated from three biologically independent experiments using three distinct sALS iPSC lines and transduced with control shRNA, p53 shRNA-1, or p53 shRNA-2 (red, magenta, grape, respectively). Each line represents the group mean (n = 3 per group), and data are presented as mean ± SEM. Statistical analysis was performed using one-way ANOVA followed by Tukey’s multiple comparison test. Immunoblot (g) analysis and quantification of CC3 (h) and SIRT1 (i) protein levels in 3-month-old sALS iMNs after neurotrophic factor withdrawal. p53 knockdown was performed using two independent shRNAs (p53 shRNA-1: magenta; p53 shRNA-2: grape) and compared to control shRNA (red). Data are presented as mean ± SEM from three biologically independent experiments using three distinct sALS iPSC lines (n = 3). Statistical significance was determined by two-way ANOVA with Sidak’s multiple comparisons test. Significance levels were defined as *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001; ns: not significant. The exact p values and all source data are provided as a Source Data file.
