FIGURE 5.

PAM increase in aging SCs drives its target gene upregulation. (a) H3K27ac ChIP‐qPCR showing increase in enrichment on PAM SE in ASCs isolated from aging (16 and 24 months) vs young (2 months) old mice. (b) RT‐qPCR showed upregulation of PAM and target genes Timp2 but not Vim in ASCs from 20 vs 2 month old mice. (c) Knockdown of PAM in aging ASC from 20 months old mice reduced the number of Pax7+/MyoD+ proliferating ASC. (d) 3C‐qPCR assay showed increase in interaction between PAM locus and Timp2 promoter in the above aging ASCs. (e) RT‐qPCR showing the expression dynamics of Timp2 in ASCs from 2, 20 and 30 months old mice. Knockdown of PAM or Ddx5 using siRNA oligo in ASCs from 20 or 30 months old mice showed down‐regulation of Timp2. (f,g) in vivo treatment of JQ1, a Brd4 inhibitor, in 10 month old mice caused down‐regulated expression of PAM and Timp2 but not Vim in FISCs (f), and reduced number of Pax7+/MyoD+ (g) in aging SC. The total number of biologically independent samples are indicated in (c&g). Data information: Data represent the mean ± SD. p‐value was calculated by two‐tailed unpaired t test (*p < 0.05, **p < 0.01). Scale bar: 100 μm