Generation of TDPΔCR mice. (A) Amino acid conservation score along an alignment of LCD of TDP-43 from 50 eukaryotic species. The histogram shows the conservation score for each position of the alignment; the red line shows the 5-aa moving average. (B) Generation of TDPΔCR mice by gene targeting using a targeting vector to replace the WT mouse TDP-43 allele with the targeted allele. Mice with the deletion of residues from 321 to 340 were produced after removal of the flippase recombinase target (Frt)-flanked selection cassette in the mutated TDP-43ΔCR allele. Diphtheria toxin A (DTA), a segment of the diphtheria toxin, was used for counter selection. (C) Genotype frequencies of WT mice (n = 16), TDPΔCR^+/− mice (heterozygous; n = 48), and TDPΔCR^+/+ mice (homozygous; n = 14) observed at postnatal day 0 (P0). (D) Kaplan-Meier survival curve of WT mice (n = 42), TDPΔCR^+/− mice (n = 55), and TDPΔCR^+/+ mice (n = 12). (E) Representative images and quantification of the body weight of WT mice (n = 16) and TDPΔCR^+/− mice (n = 16) at 3 mo old. (F) Representative immunoblot and quantification of TDP-43 protein levels in the brains of WT, TDPΔCR^+/−, and TDPΔCR^+/+ mice (n = 3–6 mice per group) at P0 or 3 mo old. (G) Relative mRNA levels of TDP-43 in the brains of WT, TDPΔCR^+/−, and TDPΔCR^+/+ mice (n = 6–8 mice per group) at P0 or 3 mo old. Data were normalized to GAPDH. Data are mean ± SEM; two-tailed Student’s t test (E–G; 3-mo-old group) or one-way ANOVA followed by Tukey’s multiple comparison test (F and G; P0 group). *, P < 0.05.