Fig. 6

Ontogenetic melanocytes and regeneration melanocytes develop from the same mFSCs. (A) Experimental procedure: kit-ts embryos were injected with the fTyrp>GFP lineage marker transposon and reared to adult stages. Following identification of fin melanocyte clones, fins were amputated and allowed to regenerate for 8 days in 25°C to reveal whether labeled clones also contribute to the regenerate. (B) Cartoon depicting the two possible relationships between ontogenetic and regeneration melanocytes. Model on the left shows predictions if ontogenetic and regeneration melanocytes develop from different mFSCs (square), model on the right shows predictions if ontogenetic and regeneration melanocytes develop from the same mFSCs. (C) Fluorescence image of labeled clone in the caudal fin center stripe before amputation. (D) Fluorescence image of the same fin at 8 dpa. White arrows indicate amputation plane. The regenerate has GFP⁺ melanocytes (green arrowheads) distal to the GFP⁺ ontogenetic melanocytes in the stump. Scale bars: 0.2 mm.