A rabbit lens epithelial cell line supports expression of an exogenous crystallin gene characteristic of lens fiber cell differentiation

Cell lines derived from the lens generally fail to maintain synthesis of crystallins in long-term culture. Here we demonstrate that the N N1003A line of undifferentiated lens epithelial cells, derived from a newborn rabbit, does not produce detectable levels of α-, β- or γ-crystallin transcripts, yet is capable of supporting the transient expression of the mouse γ2-crystallin promoter, a promoter which is active only in terminally differentiated lens fiber cells in vivo. Analysis of a set of deletion constructs suggested that sequences required for activity of the mouse promoter in N N1003A cells are similar, but not identical, to those previously shown to be essential in primary chick embryo lens explants. Therefore, these results suggest that different transcriptional factors may be capable of supporting lens-specific activity of the mouse γ2 promoter. In addition, this cell line, N N1003A , should be useful for investigations on the elements regulating γ-crystallin gene expression.