Figure 2.

DNA repair function was impaired in Per2^def cells (see also Figures S1–S3)

(A) Lin⁻/Sca-1⁺/c-Kit⁺ bone marrow derived progenitor hematopoietic stem cells (BM-pHSCs) were calculated by sorting of bone marrow cells in Per2^wt and Per2^def mice. Data are represented as mean ± SEM, n = 3, ∗∗p < 0.01, Student’s t test.

(B) Representative flow cytometry sorting images of Lin⁻/Sca-1⁺/c-Kit⁺ BM-pHSCs by indicating gating region with anti-c-Kit and anti-Sca-l in Per2^wt and Per2^def BM-pHSCs.

(C) A cluster of genes related to DNA damage repair by RNAseq analysis of Per2^wt versus Per2^def BM-pHSCs with 1.2-fold cutoff.

(D) Gene ontology biological process enrichment analysis of up-regulated DNA repair genes with 1.2-fold cutoff in Per2^wt versus Per2^def Lin⁻/Sca-1⁺/c-Kit⁺ BM-pHSCs.

(E) Western blot of a cluster of DNA repair factors of Mre11, Brca1, Rad51, Chk1, and Chk2 in Per2^wt and Per2^def BMMNCs.

(F) The effect of LDR on apoptosis measured with flow cytometry in Per2^wt and Per2^def BMMNCs 24 h after irradiation with LDR (10 cGy). Data are represented as mean ± SEM, n = 6, ∗∗∗p < 0.001, Student’s t test.

(G) The effect of LDR on the proliferation capacity of Per2^wt and Per2^def Lin⁻/Sca-1⁺/c-Kit⁺ BM-pHSCs was measured by GM-CFU assay. Data are represented as mean ± SEM, n = 3, ∗∗∗p < 0.01, Student’s t test.