Fig. 2: Functions of the hmTert gene in mice.

a Breeding strategy. Telomere length of splenocytes from 2-month-old Tert^+/-, Tert^h/-, and Tert^-/- mice were determined by Flow-FISH (b) and telomere restriction fragment (TRF) analysis (c). b Telomere Flow-FISH. Telomere signals were detected by hybridization to FAM-(CCCTAA)₃ oligonucleotide. Fluorescence signals were compared to that of wildtype C57BL/6 J mice (1.0). c TRF analysis. Splenocyte genomic DNAs were digested with HinfI and RsaI, followed by pulsed-field gel electrophoresis and Southern blotting. Positions of size markers are shown on the left (kb). d Litter sizes of breeding between Tert^+/- and Tert^-/- (red triangles), Tert^h/- and Tert^-/- (blue circles), Tert^-/- and Tert^-/- (white squares) mice. e Body weight of male (upper) and female (lower) mice at 8-week of age. f Testis weight of mice at 10–15-week age. g H&E staining of seminiferous tubules in testes from Tert^+/-, Tert^h/-, and Tert^-/- mice. Yellow arrowheads indicate aberrant tubules. h Average percentages of aberrant seminiferous tubules in testes. +/+, n = 3; +/-: G3, n = 3; G4, n = 2, G5, n = 3; h/-: G3, n = 3, G4, n = 3, G5, n = 4; -/-: G3, n = 3, G4, n = 3, G5, n = 3. i, j, Survival curves of mice with mTert, hmTert, and mTert-KO alleles. Mice were bred as shown in panel a. Kaplan-Meier survival curves of G4 (i) and G5 (j) mice are shown. P-values of survival curve comparisons were calculated using logrank test. Each datapoint in panels b, d, e, f, & h represents one biological repeat (one animal). Means ± SDs are indicated. Source data for panels b–f and h–j are provided as Source Data files.