Fig. 4: p53 regulates UVB-induced ghrelin expression.
From: Food-seeking behavior is triggered by skin ultraviolet exposure in males
a,b, Immunofluorescence analysis of the skin of control (a) male and (b) female mice (p53flx/flxFabp4Cre-) after 10 weeks of daily UVB (50 mJ/cm2) or control irradiation. Indicated skin layers stained for cyclobutane pyrimidine dimers (red), perilipin 1 (Plin1, an adipocyte marker, green) and nuclei (with DAPI, blue). c, Immunofluorescence analysis of human skin tissue at 24 h after either UVB (2,000 mJ/cm2) or mock-UVB (control) irradiation. p53 intensity was normalized to DAPI intensity. (n = 3 biologically independent human donors per condition). Representative images of male (left) and female (right) skin layers. d, mRNA levels of p53, p21 and mdm2 in the epidermis/dermis and hypodermis of indicated human skin tissue upon 5 days of either UVB (500 mJ/cm2/day) or control radiation (n = 3 biologically independent human donors per condition). Data normalized to 36b4. e, Luciferase activity downstream to the human ghrelin promoter (−3,000 bp upstream) in the presence of p53 or an empty vector (control) in H1299 cells 48 h after transfection. Firefly luciferase activity normalized to Renilla luciferase activity (n = 3 biologically independent samples per condition). f, H & E staining of adipose tissue from control (p53flx/flxFabp4Cre-) and p53-cKO (p53flx/flxFabp4Cre+) male and female mice after 10 weeks of daily exposure to UVB (50 mJ/cm2) or mock-UVB (control) irradiation. g, Relative p53, p21 mRNA levels and ghrelin from the hypodermis of dorsal skin of control (p53flx/flxFabp4Cre-) and p53-cKO (p53flx/flxFabp4Cre+) male mice after 10 weeks of daily UVB (50 mJ/cm2/day) or mock-UVB (control) irradiation (n = 3 biologically independent mice per condition). Data normalized to 36b4. h, Relative p53, p21 and ghrelin mRNA levels in the hypodermis of dorsal skin of control and p53-cKO female mice after 10 weeks of daily UVB (50 mJ/cm2/day) or mock-UVB (control) irradiation (n = 3 biologically independent mice per condition). Data normalized to 36b4. In all relevant panels: Data are presented as mean ± SEM; Two-tailed unpaired t-test p-values are shown and statistical details for sex or UVB or p53-cKO factors in the ANOVAs (F-values, degrees of freedom, p-value) with interaction appears in Supplementary Table 10.
