Meakin S O, Reddan J R, Tsui L C, Breitman M L
Division of Cancer and Cell Biology, Mount Sinai Hospital Research Institute, Toronto, Ontario, Canada.
Exp Eye Res. 1989 Jan;48(1):131-7. doi: 10.1016/0014-4835(89)90026-2.
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 alpha-, beta- or gamma-crystallin transcripts, yet is capable of supporting the transient expression of the mouse gamma 2-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 gamma 2 promoter. In addition, this cell line, N/N1003A, should be useful for investigations on the elements regulating gamma-crystallin gene expression.
源自晶状体的细胞系在长期培养中通常无法维持晶状体蛋白的合成。在此我们证明,源自新生兔的未分化晶状体上皮细胞系N/N1003A,检测不到α-、β-或γ-晶状体蛋白转录本的产生,但能够支持小鼠γ2-晶状体蛋白启动子的瞬时表达,该启动子在体内仅在终末分化的晶状体纤维细胞中具有活性。对一组缺失构建体的分析表明,小鼠启动子在N/N1003A细胞中发挥活性所需的序列与先前在原代鸡胚晶状体外植体中显示为必需的序列相似,但并不相同。因此,这些结果表明不同的转录因子可能能够支持小鼠γ2启动子的晶状体特异性活性。此外,这个细胞系N/N1003A,应该有助于研究调节γ-晶状体蛋白基因表达的元件。