Research Paper Volume 15, Issue 19 pp 9984—10009

Figure 1. Rhythmicity and abundance of core circadian clock components are altered in senescence. (A) Experimental outline for collection and culturing of cells, senescence induction and time course experiment. (B, C) SA-β-gal staining and qPCR for CDKIs p16^INK4a and p21 in cells isolated from C57/BL6 mice. (D) Expression of core circadian clock genes Bmal1, Nr1d1, Per2, and Cry1 in control and senescent cells. (E) Quantification of relative amplitude of Bmal1, Nr1d1, Per2, and Cry1 in control and senescent cells. (F) Quantification of period of Bmal1, Nr1d1, Per2, and Cry1 in control and senescent cells. (G) Representative western blot and quantification of BMAL1 in control and senescent cells, normalized to β-actin. Data is presented with mean +/− SEM; two-tailed unpaired Student’s t-test (C, E, F) and one-way ANOVA tests with Dunnett’s post hoc test for multiple comparisons (G) were used with significance indicated as ^*P < 0.05, ^**P < 0.01, ^***P < 0.001, ^****P < 0.0001. n = 4 replicates for senescent qPCR, n = 6 for control qPCR, n = 3 replicates for western blots. Scale bar in (B) is 400 μm.