Figure 1.
Quantitative PCR analysis of selected NER genes.
Quantitative expression of 11 genes identified from microarray data, with known functional significance related to NER, was determined (a). We also reconfirmed differential gene expression of melanocyte markers (tyrosinase, tyrosinase related protein 1) as validation (b). Trends for upregulation or down-regulation were largely consistent with microarray data.
Figure 2.
Co-expression of ERCC3 and melanocyte marker gp100 in hair follicles and pigmented nevi.
Dual label immunofluorescence defined ERCC3 expression in relation to mature melanocytes and melanocyte stem cells in terminal hair follicles in normal scalp biopsies and nevi tissues. A few dual labeled gp100 positive (green) mature melanocytes and ERCC3 positive (red) cells were detected in pigmented hair follicle bulb regions (a). Dual labeling of isolated cells was also located close to the hair bulge region, suggesting these may be ERCC3 positive melanocyte stem cells (b). Moderate ERCC3 protein expression was detected in mature melanocytes with strong gp100 expression in nevi tissues (c). Bar = 40 µm.
Figure 3.
Effects of ERCC3 siRNA transfection on ERCC3 and TYR mRNA levels in human epidermal melanocyte cells.
Cells transfected with ERCC3 siRNA displayed a statistically significantly lower level of ERCC3 mRNA than negative control siRNA transfected melanocytes (a). There was a corresponding reduction in TYR mRNA levels in ERCC3 siRNA transfected cells compared with negative control siRNA transfected cells (b). These experiments were repeated 3× with similar results. *, p≤0.05 versus control.
Figure 4.
Effect of ERCC3 siRNA transfection on tyrosinase activity in ERCC3 siRNA and negative control siRNA transfected human epidermal melanocytes.
Cells were transfected with ERCC3 siRNA and negative control siRNA tyrosinase activity were evaluated by measuring l-DOPA oxidation at several different time points at 475 nm. The data were normalized to the cell number. The data show the means ± S.D. of three experiments performed in duplicate. *, p≤0.05 versus control.
Figure 5.
Pigmented and non–pigmented microdissected human hair follicles.
Hair follicles were separated into sample groups; those with pigmentation, where the dermal papilla was hidden in a strongly pigmented hair bulb and pigment-presence was evident in the hair shaft (a). The few hair follicles with apparent pigmentation dilution, but not fully devoid of pigmentation, were discarded (b); and those where no pigmented melanocytes could be observed macroscopically in the hair bulb and the hair shaft appeared as fully unpigmented white hair (c).