Fig 4. Abca12^smsk/smsk displays defects in terminal differentiation.

(a). Cell proliferation rates were similar in both WT and smsk embryonic epidermis as determined by in utero incorporation of 5-bromo-2'-deoxyuridine (BrdU). Sections were stained with an anti-BrdU antibody (green) and counterstained with KERATIN 14 (KRT14) (red). Note that no difference in the expression pattern of KRT14 was observed in either WT or mutant epidermis. Bars = 25 μm. (b) Keratinocytes in Abca12^smsk/smsk mutant skin undergo abnormal terminal differentiation as demonstrated by scattered pattern of KRT1 (red) detection in the SC. Bars = 50 μm. (c) KRT16 (red) was ectopically expressed in the interfollicular suprabasal keratinocytes of Abca12^smsk/smsk epidermis, whereas it was undetecteable in the WT epidermis. Furthermore, the retention of nuclei (parakeratosis) in the SC is observable in smsk mutant skin. Bar = 25 μm.