Research Paper Volume 6, Issue 6 pp 496—510

Figure 4. Utricular supporting cells show age-dependent resolution of γH2AX foci following cell cycle re-entry. AdcD1-infected P6 and P50 utricular explants were analyzed at 3, 7 and 14 DIV. (A) Quantification shows a prominent decrease in the amount of EdU+ SCs with γH2AX foci in P6 utricles from 3 to 7 DIV. (B) Quantification shows a prominent decrease in the amount of EdU+ SCs with γH2AX foci in P50 utricles not before 14 DIV. (C,C') At 7 DIV, AdcD1-infected P50 utricles show SCs with intense, pan-nuclear γH2AX staining. These cells co-express cleaved caspase-3. (D) At 7 DIV, quantification shows a highly significant difference between AdcD1-infected juvenile and adult utricles in the proportion of γH2AX+ SCs with intense, pan-nuclear expression out of the total population of γH2AX+ SCs. Mean ± SEM and the number of explants (n) are shown. Statistical significance: ***, p < 0.005. Abbreviations: AdcD1, adenovirus encoding cyclin D1; Casp3, cleaved caspase-3; γH2AX, Ser 139 phosphorylated histone H2AX; utr, utricle. Scale bar, shown in C': C,C', 5 µm.