Figure 2.

Pathology in eyelid, an epithelial appendage to protect the eye. A: Normal size eye slits of 4-month-old control C57BL/6J mouse. B: Narrow eye slits in 4-month-old K14-Noggin mouse. Eyelids remain partially fused. Eyeballs are of the same size (not shown). Arrowheads point at inward-growing cilia. C–F: Eyelid suture of newborn control mouse. C: Strong K14 immunostaining is seen in the epidermal side, suture, and conjunctival side of the eyelid. D–F: Whole mount in situ hybridization of 1-mm-thick eyelid stripe. Green color is computer pseudo-coloring. BMP2 transcripts are expressed predominantly on the conjunctivae side whereas BMP4 is distributed more evenly throughout the eyelid suture. Msx2 transcript distribution is similar to BMP4. G and H: Corner of eyelids (commissure, corresponding to the areas outlined with red on A and B) of adult mice. Formation of ectopic pillosebaceous units at the expense of Meibomian glands in high copy number TG K14-Noggin mice (hcn TG K14-Noggin mice). Scale bars, 100 μm.