Cultured chicken embryo lens cells resemble differentiating fiber cells in vivo and contain two kinetic pools of connexin56

被引:32
作者
Berthoud, VM
Bassnett, S
Beyer, EC
机构
[1] Univ Chicago, Sect Pediat Hematol Oncol, Dept Pediat, Chicago, IL 60637 USA
[2] Washington Univ, Sch Med, Dept Ophthalmol & Visual Sci, St Louis, MO 63110 USA
关键词
lens; gap junction; connexin; N-cadherin; turnover; endoplasmic reticulum;
D O I
10.1006/exer.1998.0635
中图分类号
R77 [眼科学];
学科分类号
100212 ;
摘要
The lens is an avascular organ in which gap junctions play a pivotal role for cell physiology and transparency. Here we evaluate a lens culture system as a model for studies of lens gap junction dynamics. In culture, chicken embryo lens cells initially form a monolayer of epithelial cells. Subsequently, the epithelial cells differentiate into lentoids, birefringent multicellular structures composed of fiber-like cells. We examined the cultures for the expression of cellular markers and lens fiber specific proteins using immunofluorescence and immunoblot analysis. We also determined the half-life of connexin56 (Cx56), a fiber-specific gap junction protein. All lens cells in culture expressed actin, endoplasmic reticulum proteins and N-cadherin. Only lentoid cells expressed the lens fiber connexins, Cx45.6 and Cx56. Cx56 localized at appositional membranes and did not co-localize with endoplasmic reticulum proteins or N-cadherin. Two pools Of Cx56 were detected in these cultures, one with a half-life of a few hours and the other with a half-life of days. The two pools contained phosphorylated forms of Cx56 of different apparent molecular weights. These results suggest that lens cells in culture can be used as a model for the study of lens biology. They also suggest that phosphorylation of Cx56 might be regulating the stability of the protein. (C) 1999 Academic Press.
引用
收藏
页码:475 / 484
页数:10
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