Fig 2: aPKC? inhibits proliferation of LRCs in acinar compartment. (A) Experiment setup. Label-retaining assay was performed in Prkcz-/- and wild-type (C57BL/6 J) mice as described in methods section (n = 3 for all groups). PGs were collected 5 days following radiation treatment for analysis. (B) Percentage of Ki67-positive LRCs in acinar compartment of Prkcz-/- and wild-type mice. Representative images of control and irradiated PGs immunostained for EdU (Green) and Ki67 (Magenta) are shown in panels C–F. Proliferative LRCs are shown with a white arrow. Different letters represent statistical differences between groups (p < 0.05 by one-way ANOVA with follow up Tukey’s multiple comparisons test).

Fig 3: aPKC? is required for functional restoration of irradiated salivary glands with IGF1. Saliva was collected from wild type (C57BL/6 J) and Prkcz-/- mice at days 3 and 30 following radiation treatment as described in the methods section. A minimum of 9 males and 3 females were used per group for saliva collection at day 3. At day 30, at least 5 animals were used for each treatment group. Values for each mouse strain were normalized to their respective untreated control groups. Statistical differences between groups are represented by a star (p < 0.05, One-way ANOVA followed by Tukey’s multiple comparisons test).

Fig 4: IGF-1 inhibits radiation-induced nuclear translocation of Yap in acinar LRCs. (A) Label-retaining assay was performed in Prkcz-/- and wild-type (C57BL/6 J) mice as described in methods section (n = 3 for all groups). 4 days following radiation, animals were injected with 1 or 4 doses of IGF-1 (5 ug/mouse) 24 hours apart. PGs were collected 24 hours following the last dose of IGF-1 (at day 5 or 8 following radiation). (B–E) Representative images of PGs stained for Yap (Magenta) and EdU (Green). White arrows point at Yap-positive LRCs with nuclear Yap. (F) Quantification of the percentage of Yap-positive acinar LRCs. (G) Quantification of the percentage of nuclear-Yap-positive acinar LRCs. Star represents statistical differences vs untreated group (p < 0.05 by one-way ANOVA with follow up Tukey’s multiple comparisons test).

Fig 5: Radiation promotes nuclear translocation of Yap in acinar LRCs downstream of aPKC?. Immunostaining for Yap (magenta) and EdU (green) of PGs from wild type (C57BL/6 J) and Prkcz-/- mice are shown in panels A–D. White arrows point at Yap-positive LRCs with nuclear Yap. Yellow stars indicate LRCs with membrane/cytoplasmic Yap. (E) Quantification of the percentage of Yap-positive acinar LRCs. (F) Quantification of the percentage of Nuclear-Yap + LRCs in acinar compartment (white arrows). At least 3 mice were used for each group. One-way ANOVA followed by Tukey’s multiple comparisons test was performed. Stars represent statistical differences vs wild type untreated group (p < 0.05).