Cattini P A, Eberhardt N L
Nucleic Acids Res. 1987 Feb 11;15(3):1297-309. doi: 10.1093/nar/15.3.1297.
The expression and hormonal regulation of chimaeric genes containing the 5'-flanking regions of the normal human growth hormone (hGH-1), the variant hGH (hGH-2) and chorionic somatomammotropin (hCS-1) genes fused to the chloramphenicol acetyl transferase (CAT) gene has been examined after transient transfection into cultured rat pituitary (GC), and non-pituitary (HeLa and Rat 2) tumor cells. As assessed by levels of CAT activity, the hGH-1 and hCS-1 gene hybrids were expressed at 5- to 25-fold higher levels in GC cells than in HeLa or Rat 2 cells. The hGH-2 gene hybrid was expressed at very low levels in all 3 cell types. Triiodothyronine treatment of transiently transfected GC cells had little effect on CAT activity from the hGH-1 gene hybrid but increased CAT activity from the hCS-1 gene hybrid. A slight but significant increase in CAT expression was detected with both genes after dexamethasone treatment. The data indicate that elements present on the hGH-1 and hCS-1 genes' 5'-flanking DNA are required for the efficient expression of these genes in GC cells.
将含有正常人生长激素（hGH - 1）、变异型hGH（hGH - 2）和绒毛膜生长催乳素（hCS - 1）基因5'侧翼区并与氯霉素乙酰转移酶（CAT）基因融合的嵌合基因，在瞬时转染培养的大鼠垂体（GC）和非垂体（HeLa和大鼠2）肿瘤细胞后，对其表达和激素调节进行了研究。通过CAT活性水平评估，hGH - 1和hCS - 1基因杂种在GC细胞中的表达水平比在HeLa或大鼠2细胞中高5至25倍。hGH - 2基因杂种在所有3种细胞类型中的表达水平都非常低。对瞬时转染的GC细胞进行三碘甲状腺原氨酸处理，对hGH - 1基因杂种的CAT活性影响不大，但增加了hCS - 1基因杂种的CAT活性。地塞米松处理后，两个基因的CAT表达均有轻微但显著的增加。数据表明，hGH - 1和hCS - 1基因5'侧翼DNA上存在的元件是这些基因在GC细胞中高效表达所必需的。
