Extended Data Fig. 1: miR-31 upregulation is an early event in both HFSC aging and wound response.
From: A stress-induced miR-31–CLOCK–ERK pathway is a key driver and therapeutic target for skin aging
a, Whole-mount IF staining of mouse backskin epithelium isolated by EDTA digestion. VIM: vimentin. Scale bars, 50μm. b, In situ hybridization of young (8 weeks)/old (22 months) backskin sections. Brackets: HF Bulge. Scale bars: 50μm. c, FACS sorting profiles of young (8 weeks)/middle (12 months)/old (22 months) HFSCs (CD34 + CD49fhi, boxed). d, In situ hybridization of young/old backskin sections, samples were collected at 10 days post depilation. Brackets: HF Bulge. Arrow heads: HF matrix. Scale bars: 50μm. e, Oil red staining of same animal Rad/noRad backskin sections at A2. Scale bars: 50 μm. Arrows: SG. f, Left panel: photos of backskin full-thickness wound healing of LIR or Ctrl mice at A1 time. d0-9: days post wounding. Scale bar: 5 mm. Right panel: Quantification of the left healing process. Vertical axis: % of wound healed. P values are for Rad vs noRad, n = 3 biologically independent mice. g, Left panel: white-field images of A1 time backskin exoplant cultures at day 6. Dash lines: borders of migrating keratinocyte sheet (MK sheet). #:originalexoplants. Scale bars: 100μm. Right panel: Quantification of the MK sheet area. Vertical axis: relative % of MK sheet area vs Ctrl-L. n = 6 exoplants separated from 3 mice. h, Left: representative FACS profiles of same animal noRad/Rad skin at A1 time. Box and %: CD49fhiCD34 + HFSCs and its % among CD49f + cells. Right: quantification of relative HFSC % vs noRad. **: p < 0.01, two-tail t-test, n = 4 biologically independent mice. i, Left panel: Skin surface images of same animal noRad/Rad areas at different days (d) after Wax2. Scale bars: 500 μm. Right panel: Quantification of relative hair density in same animal noRad/Rad backskin regions at A2. **: p < 0.01, two-tail t-test, n = 9 samples separated from 3 mice. j, Whole-mount IF staining and HF size quantification of same animal Rad/noRad backskin epithelium at A2. n = 5 HFs. Scale bars: 50 μm. For all relevant figures, data are represented as mean ± SEM. P values were calculated with two tail t-test.
