Journal: JID Innovations

Article Title: Spatiotemporal fluorescence imaging of microRNA activity in 3-D models of human epidermis reveals contribution of the Notch pathway in the regulation of miR-30a in aging skin

doi: 10.1016/j.xjidi.2025.100444

Figure Lengend Snippet: The inhibition of the Notch pathway increases miR-30a activity. (a ) Representative images of reconstructed epidermises obtained using RIFES miR-30a-3p or miR-30a-5p primary keratinocytes. The green fluorescence corresponds to GFP, and the blue fluorescence corresponds to nuclei labeled with DAPI. The limit of the epidermis is indicated by a dotted line. Bar = 50 mm. ( b ) Immunofluorescence labeling of Notch 1 (denoted as NICD) in a skin biopsy (female abdominal skin, young adult). The red fluorescence corresponds to Notch1, the green fluorescence corresponds to loricrin, and the blue fluorescence corresponds to nuclei labeled with DAPI. Bar = 50 mm. ( c ) Western blot analysis of Notch1 (denoted as NICD), cleaved Notch1, and actin in HPKs treated or not by DAPT. ( d ) HEY1 transcript relative expression analysis by qRT-PCR in HPKs treated or not by DAPT (mean ± SD, n = 3, ∗ P < .05 t -test P -value). ( e ) Response of the RIFES miR-30a-3p or -5p HPKs to DAPT treatment. The graph corresponds to the quantification of the GFP fluorescence by HCS after DAPT or control treatment (box plot with Tukey whiskers, n = 4, ∗ P < .05 t -test P -value). Representative images of cells are shown (Merge image: GFP plus DAPI). ( f ) Western blot analysis of GFP and actin expression in lentiRIFES/miR-30a-3pT or 5pT HPKs after DAPT treatment. ( g ) Reconstructed epidermises were obtained using lentiRIFES/miR-30a-3pT or 5pT keratinocytes. The RHEs were treated or not by the DAPT compound. Representative images of GFP fluorescence or K10 immunofluorescence are shown. The limit of the epidermis is indicated by a dotted line. Bar = 50 mm. A small area of the images surrounded by a frame is shown at higher magnification. ( h ) miR-30a-3p or miR-30a-5p transcript expression analysis by qRT-PCR in HPKs treated or not by DAPT (mean ± SD, n = 3, ∗ P < .05 t -test P -value). HCS, high-content screening; HPK, human primary keratinocyte; K10, keratin 10; RHE, reconstructed human epidermis.

Article Snippet: Membranes were blocked with 10% nonfat dry milk for 1 hour and incubated with primary antibodies against NOTCH 1 (number 3608, Cell Signaling Technology), cleaved NOTCH-1 (number 4147, Cell Signaling Technology), c-MYC, or β-actin (ab8227, Abcam) overnight at 4 °C.

Techniques: Inhibition, Activity Assay, Fluorescence, Labeling, Immunofluorescence, Western Blot, Expressing, Quantitative RT-PCR, Control, High Content Screening