iNs display molecular properties of interneurons at day 26 after transduction. (A) RT-qPCR analysis of PVALB gene expression in ALN + shREST reprogrammed neurons and comparison with ADLSF. Two-tailed unpaired t-test with Welch´s correction (n = 7 for ALN + shREST): * p = 0.025; df = 15; dashed line represents mean average of PVALB mRNA levels in ADLSF condition (see Figure 2A). (B,C) TAU+ and PV+/TAU+ cells in ALN + shREST reprogrammed neurons, (B) immunocytochemistry, and (C) quantification with comparison to ADLSF. Two-tailed unpaired t-test with Welch´s correction (n = 7 for ALN + shREST): **** p < 0.0001; df = 12.07; dashed line represents mean average of PV+/TAU+ cells in ADLSF condition (see Figure 2F). (D) RT-qPCR analysis of ADLSF reprogrammed cells showing upregulation for subtype-specific GABAergic interneuron markers. Kruskal-Wallis test, Dunn’s multiple comparisons test (n = 4–8 for CTRL GM, n = 5–8 for CTRL NDiff, n = 4–8 for ADLSF): *** p < 0.005; ** p 0.01; * p < 0.05; ns, not significant. (E,F) Reprogrammed CALB1+/TAU+ (n = 3) at 26 days post transduction, (E) immunocytochemistry, and (F) quantification. (G) RT-qPCR analysis of different neuronal lineage markers in ADLSF-reprogrammed cells. Kruskal–Wallis test, Dunn’s multiple comparisons test (n = 4–5 for CTRL GM, for CTRL NDiff and ADLSF): ** p < 0.01; * p < 0.005; ns, not significant. Data are presented as mean ± SEM. Each datapoint represents a replicate from an independent experiment. Scale bar: (B,E) 50 μm.