Fig. 3. System for in vivo labeling of the cells in the melanocyte lineage with GFP. Existence of MSCs in an isolated single hair follicle. Arrowheads indicate that MSCs reside in the lower permanent portion of the hair follicle. (B) Strategy for marking melanocytes with GFP. (C,D) GFP expression in a hair follicle and the embryonic epidermis. (E) FACS analysis of a single-cell suspension obtained from the epidermis of a melanocyte-specific GFP transgenic mouse at E16.5. The single-cell suspension was stained with PE-anti-CD45 and APC-anti-c-Kit, and processed for FACS analysis. The FACS profile of the cells in CD45-negative population is shown. Scale bars: 50 µm.