Fig 1. Features of Far2^-/- mice.

Heterozygous mouse (A, left; B, top) with a normal thick black hair coat. By contrast, a homozygous Far2^-/- mouse (A, right; B, bottom) had focal alopecia on the top of its head behind the ears. Far2^{tm1(KOMP)Wtsi}/2J mice (normal with a LacZ reporter gene) expressed LacZ only in sebaceous glands (C). Genotyping differentiates wildtype (Far2 ^+/+), heterozygous (Far2^+/-), and mutant (Far2^-/-) mice (D). Plucked hair shafts taken from a Far2^-/- mouse adjacent to areas of alopecia were indistinguishable from normal (E). By scanning electron microscopy there were no obvious structural differences in hair shafts between the normal heterozygous (F) or null (G, I, J) Far2 mice in either whole skin mounts with hair (F, G) or plucked hairs mounted in groups. Histologically, wildtype sebaceous glands had pale cytoplasm with fine clear vacuoles, the contents of which could not be seen in routine sections once the cells ruptured (K). By contrast, sebaceous glands in Far2^-/- mice had bright eosinophilic cytoplasm that, when ruptured into the sebaceous duct, formed clumps of amphophilic material (O). SOAT1 immunolabeled sebocytes at the base of the sebaceous gland in both genotypes (L, P). Perilipin 2 (PLIN2; also called adipophilin) labeled the sebocytes near the base of the gland in normal mice (M) but also labeled the extruded material within the infundibulum and sebocytes in the Far2 null mice (Q). Keratin 14 (KRT14) normally labels basal cells and hair follicle root sheath cells with weak cell membrane labeling of sebocytes (N), but in the Far2^-/- mice sebocytes were heavily labeled as was the extruded material within the infundibulum (R).