Fig 2: Additional examples of MYOCD-driven differential exon usage include SLMAP, CALD1, and VCL. SLMAP which encodes sarcolemma associated protein, was among the striking examples in the exon-based analysis. Reads mapping to 3´, late, exons were increased relative to early exons (A). Late exons are represented in the two annotated mRNA isoforms shown in light blue in (B). Western blotting showed SLMAP bands at 40 and 30 kDa that increased dramatically with MYOCD compared to null virus, while bands at 80 and 70 kDa remained inert (C). After blotting for SLMAP, the membrane was stripped and re-probed for HSP90 (D). Panel E shows western blotting for caldesmon (null: −; MYOCD: +). Heavy (h-CALD1) and light caldesmon (l-CALD1) variants were resolved, and intensity was adjusted to clearly show the heavy isoform in the top blot (long), and the lower band in the middle blot (short). Quantification, shown at the bottom, demonstrated a greater relative increase of h-CALD1 compared to l-CALD1. MYOCD similarly promoted expression of meta-vinculin (F), which is a SMC-enriched ≈ 150 kDa splice variant derived from the VCL gene, relative to vinculin (≈ 130 kDa)

Fig 3: Gel-SHP promotes hair follicle regeneration via modulating Cald1 expression during the remodeling stage. (a) Gel-SHP promotes Ki67 expression in neonatal hair follicle matrix cells. Immunofluorescence (IF) stained sections (left; 7 day of treatment). The Ki67-positive follicles (follicles with Ki67-positive cells were defined as positive follicles) ratio (n = 5, p = 0.01081) and the number of positive cells in positive follicles (15 randomly selected hair follicles:3 follicles close to the wound per section, n = 15, p = 1.058E-4) were significantly higher in Gel-SHP group than in Gel group. (b) Western blot results of L929 showed that SHP099 promoted Cald1 expression in fibroblasts. (c) IF results (left, day 3 incubated) showed that SHP099 altered the morphology of fibroblasts and significantly decreased the length/width ratio of fibroblasts (n = 10, p = 1.17055E-9). (d, e) Gel-SHP promotes Cald1 expression in wound fibroblasts. (d) IHC stained sections of Cald1 (day7 of treatment; red). (e) Cald1 AOD in wound fibroblasts in Gel-SHP group was significantly higher than that in Gel group (n = 5, p = 2.62218E-4). (f–h) Gel-SHP promotes Cald1 expression in neo-regenerated hair follicles. (f) IHC stained sections of Cald1 (day 7 of treatment; red). (g) Cald1 positive neo-regenerated hair follicle percentage in Gel-SHP group was significantly higher than that in Gel group (n = 5, p = 6.04142E-5). (h) Cald1 AOD in neo-regenerated hair follicles in Gel-SHP group was significantly higher than that in Gel group (10 randomly selected hair follicles:2 follicles close to the wound per section, n = 10, p = 2.86295E-8). (i) Gel-SHP maintains the dermal shell of hair follicles to promote follicular regeneration by promoting Cald1 expression during the remodeling stage. *p < 0.05; **p < 0.01; ***p < 0.001; ****p < 0.0001.