Nebes V L, Morris S M
Department of Microbiology, Biochemistry and Molecular Biology, University of Pittsburgh, PA 15261.
Biochem J. 1987 Aug 15;246(1):237-40. doi: 10.1042/bj2460237.
Dexamethasone is necessary and sufficient to induce mRNA for phosphoenolpyruvate carboxykinase (GTP) (PEPCK) by 19-fold in rat hepatocytes cultured in serum-free medium. However, the time required for maximum induction is 16 h. The slow induction suggested that glucocorticoids regulate the expression of an intermediate gene product(s) which is required for glucocorticoid stimulation of PEPCK-gene expression. Consistent with this notion was the finding that cycloheximide completely blocked the response to dexamethasone. In contrast, cycloheximide did not block the response to a cyclic AMP analogue.
在无血清培养基中培养的大鼠肝细胞中,地塞米松足以使磷酸烯醇丙酮酸羧激酶(GTP)(PEPCK)的mRNA诱导19倍,且是必需的。然而,最大诱导所需时间为16小时。这种缓慢诱导表明糖皮质激素调节一种中间基因产物的表达,而该产物是糖皮质激素刺激PEPCK基因表达所必需的。与此观点一致的是,环己酰亚胺完全阻断了对地塞米松的反应。相反,环己酰亚胺并未阻断对环磷酸腺苷类似物的反应。