Figure 2. ATR hypomorphic suppression has a minimal impact on normal tissue homeostasis.

(A) H&E-stained sections of humeral bones from tamoxifen-treated mice at the indicated time points after initial treatment. Original magnification, ×200. (B) Absolute number of myeloid cells (Mac1⁺Gr1⁺) obtained from 4 hind limb bones of mice at the indicated time points (n = 5–15 mice per genotype, per time point). (C) H&E-stained sections of intestines from tamoxifen-treated mice at the indicated time points after initial treatment. Original magnification, ×200. (D) Weight of mice at the indicated time points. (E and F) Abundance of the ATR^fl-recombined allele (ATR^Δ) in the bone marrow (E) and intestines (F) of tamoxifen-treated mice. Time points represent the number of days after tamoxifen treatment. The frequency of ATR^fl recombination was determined by qPCR amplification of the ATR^fl allele from genomic DNA isolated from each tissue (n = 5–15 mice per genotype, per time point). Data show mean ± SEM.