Hayashi S, Kondoh H, Yasuda K, Soma G, Ikawa Y, Okada T S
EMBO J. 1985 Sep;4(9):2201-7. doi: 10.1002/j.1460-2075.1985.tb03915.x.
A cloned delta-crystallin gene of the chicken is preferentially expressed in lens cells after introduction into various mouse tissues. The level of expression in the lens epithelium is 20 times higher than in fibroblasts. Taking advantage of this system, we attempted to define regulatory regions of the delta-crystallin gene using a variety of deletion and substitution mutants. The results indicate that tissue-specific regulation of the delta-crystallin gene is mediated by the 5' end region of the gene; sequences upstream from -93 are not required for expression and sequences downstream from +58 are not involved in tissue specificity. The high expression in lens cells requires 5' flanking sequences of 80-bp long from the cap site, whereas the low expression in fibroblasts requires an additional 12 bp upstream sequence. Expression of both types is lost in a mutant with only 51 bp of the 5' flanking sequence. Thus, fine deletion analysis demonstrated that expression in lens cells and expression in fibroblasts are distinct not only in level but in regulation.
鸡的一个克隆的δ-晶体蛋白基因在导入各种小鼠组织后，优先在晶状体细胞中表达。晶状体上皮中的表达水平比成纤维细胞高20倍。利用这个系统，我们试图用各种缺失和替代突变体来确定δ-晶体蛋白基因的调控区域。结果表明，δ-晶体蛋白基因的组织特异性调控是由该基因的5'端区域介导的；-93上游的序列对于表达不是必需的，而+58下游的序列不参与组织特异性。晶状体细胞中的高表达需要从帽位点起80个碱基对长的5'侧翼序列，而成纤维细胞中的低表达需要额外的12个碱基对上游序列。在一个只有51个碱基对的5'侧翼序列的突变体中，两种类型的表达都丧失了。因此，精细的缺失分析表明，晶状体细胞中的表达和成纤维细胞中的表达不仅在水平上不同，而且在调控上也不同。
