Ontogeny of alpha-crystallin subunits in the lens of human and rat embryos.
The distribution of alpha A- and alpha B-crystallin in the developing lens of human (Carnegie stages 13 to 23) and rat embryos (embryonic days E11 to 18) was examined immunohistochemically. In a human embryo at stage 13, the lens placode was already immunoreactive to alpha B-crystallin, but not to alpha A-crystallin. At stage 15, the lens vesicle was intensely immunoreactive both to alpha A- and alpha B-crystallin. From stages 16 to 23, the lens epithelial cells and fiber cells were immunoreactive to alpha A- and alpha B-crystallin. In rat embryos, alpha A-crystallin appeared in the lens pit at E12, and alpha B-crystallin appeared in the elongating lens fiber cells at E14. From E15 to E18, the lens epithelial cells and fiber cells were immunoreactive to alpha A-crystallin. The lens fiber cells were also immunoreactive to alpha B-crystallin, but the epithelial cells were not. These findings suggest that alpha B-crystallin appears earlier than alpha A-crystallin in the human lens, but at a later period than alpha A-crystallin in the rat lens. alpha B-Crystallin was not detected in the epithelial cells of the rat lens, but was persistently present in the epithelial cells of the human lens.
Oguni
M
M
Department of Anatomy, Shimane Medical University, Izumo, Japan.
Setogawa
T
T
Hashimoto
R
R
Tanaka
O
O
Shinohara
H
H
Kato
K
K
D000818:Animals; D003459:Crystallins / Q000032:analysis*; D005314:Embryonic and Fetal Development; D004847:Epithelial Cells; D004848:Epithelium / Q000737:chemistry; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007908:Lens, Crystalline / Q000737:chemistry* / Q000166:cytology / Q000196:embryology*; D008297:Male; D011247:Pregnancy; D051381:Rats; D017208:Rats, Wistar
D003459:Crystallins