a-b, Silencing MAPT-AS1 in SH-SY5Y cells with siRNAs (si-NAT1, si-NAT2, siEx4) unaffected MAPT expression by qRT-PCR but increased endogenous tau compared to scramble mean (n=6 independent treatments, mean±s.d., two-sided Kruskal-Wallis with Dunn’s test). c, (left) Representative immunostainings of MNs transduced at four multiplicities of infection (MOI) with negative control LV-shRen or MAPT-AS1-specific shNT1, shEx4. Nuclei labelled by SYTOX (green), total-Tau (red) normalised to wheat germ agglutinin (WGA), scale bar=40 μm. (right) ICC quantification (n=10±1 wells across 3 experiments, n=23 wells for shRen-250MOI, box-plots: midpoints, medians; boxes, 25th and 75th percentiles; whiskers, minima and maxima; two-sided Kruskal-Wallis with Dunn’s test). d, Immunoblots of MNs from two healthy donors (MN-ctrl1, MN-ctrl2) transduced with LV-shEx4 or LV-shRen, total-tau normalised to GAPDH (n=5 shRen, n=6 shEx4, independent transductions, mean±s.d. two-sided unpaired Wilcoxon-test).