Figure 6
Delayed wound healing in Notch1-depleted mouse skin. (a) Transcripts of Notch1, Hes1, RhoU, PLAU, and GAPDH were determined in mouse skin wound by quantitative PCR (n = 6/group). (b~d) Following topical application of JMJD3 siRNA or NF-κB p65 siRNA or Notch1 siRNA in 30% Pluronic F-127 gel, wound tissue was harvested and transcripts of Notch1, Hes1, RhoU, PLAU, and GAPDH were determined by quantitative PCR (n = 6/group). (e,f) Depletion (siNotch1) or inactivation (DAPT) of Notch1 results in delayed skin wound closure. Following the application of Notch1 siRNA or DAPT, the wounded skins were photographed and a percentage of the wound area was measured quantitatively (n = 6/group). (g) A proposed model. Upon wounding, NF-κB p65 and JMJD3 binds to Notch 1 gene promoter to activate Notch 1 gene expression through demethylation of H3K27me3. The cleaved intracellular domain of Notch1 (NICD) binds to RhoU and PLAU gene promoters and activates RhoU and PLAU gene expression. These events result in enhanced filopodia formation, decreased focal adhesion and actin stress fiber formation in keratinocytes, leading to keratinocyte migration.
