Effects of c-Jun and a negative dominant mutation of c-Jun on differentiation and gene expression in lens epithelial cells

✍ Scribed by Jo Ann Rinaudo; Emanuel Vacchiano; Peggy S. Zelenka

• Publisher: John Wiley and Sons
• Year: 1995
• Tongue: English
• Weight: 1016 KB
• Volume: 58
• Category: Article
• ISSN: 0730-2312
• DOI: 10.1002/jcb.240580212

✦ Synopsis

Abstract

We have used a retroviral vector (RCAS) to overexpress wild‐type chicken c‐Jun or a deletion mutant of chicken c‐Jun (JunΔ7) lacking the DNA binding region to investigate the possible role of c‐Jun in lens epithelial cell proliferation and differentiation. Both constructs were efficiently expressed in primary cultures of embryonic chicken lens epithelial cells. Overexpression of c‐Jun increased the rate of cell proliferation and greatly delayed the appearance of “lentoid bodies,” structures which contain differentiated cells expressing fiber cell markers. Excess c‐Jun expression also significantly decreased the level of β~A3/A1~‐crystallin mRNA, without affecting αA‐crystallin mRNA. In contrast, the mutated protein, JunΔ7, had no effect no proliferation or differentiation but markedly increased the level of αA‐crystallin mRNA in proliferating cell cultures. These results suggest that c‐Jun or Jun‐related proteins may be negative regulators of αA‐ and β~A3/A1~‐crystallin genes in proliferating lens cells.