Figure 2.

Embryonic mouse expression of Mc1r RNA (blue) and Mc1r protein expression (brown). a, b. Embryonic day of gestation E9.5, frontal sections, antisense probe. a′. Hybridization of adjacent section to sense‐transcribed probe (negative control). c. Mc1r expression is widespread at E13.5. d. Facial, head and neck tissues at E13.5. e, f. Immunohistochemistry in sagittal and transverse section respectively at E15.5. g, g′. Hair follicles of skin (g) and whisker vibrissae (g′) at E17.5. h. Frontal section of head, E17.5. i. Oblique section through dorsal trunk, E17.5. j. Frontal section through ventral trunk, E17.5. k: Postnatal day 2 forebrain. l. Adult skin, hair follicles with black pigment sheath. Abbreviations: ad, adrenal gland; ao, aorta; br, bronchi; bo, basioccipital cartilage; bs, basisphenoid; cp, choroid plexus; d, diaphragm; drg, dorsal root ganglion; fb, forebrain; fl, forelimb; fp, foreplate; h, heart; hb, hindbrain; hp, hippocampus; IRS, inner root sheath; ivd, intervertebral disc; k, kidney; Li, liver; le, lens; Lu, lung; m, muscle; ma, mandibular artery; Mc, Meckel's cartilage; nc, nasal cartilage; ne, nasal epithelium; oe, oesophagus; ov, otic vesicle; p, pancreas; pit, pituitary; r, rib; ret, retina; sc, spinal cord; scc, semi‐circular canal; si, small intestine; St, stomach; t, tongue; te, temporalis muscle; v, vertebra