Bogue C W, Jacobs H C, Dynia D W, Wilson C M, Gross I
Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut 06520, USA.
Am J Physiol. 1996 Nov;271(5 Pt 1):L862-8. doi: 10.1152/ajplung.1996.271.5.L862.
Retinoic acid has both early or immediate (within hours) and late (after days) effects on gene expression. We studied the early effects of retinoic acid on the surfactant protein (SP) genes. Exposure of fetal rat lung explants to all trans-retinoic acid for 4 h resulted in a significant dose-dependent increase in SP-A, -B, and -C mRNA with markedly different dose-response characteristics. The maximal (2.5x) increase in SP-A mRNA was observed with 10(-10) M retinoic acid, whereas treatment with 10(-5) M resulted in a tendency to decreased levels. In contrast, maximal stimulation of SP-C (6x) was noted at 10(-5) M retinoic acid and that of SP-B (2x) at 10(-7) to 10(-5) M retinoic acid. Similar differences in the dose-response characteristics of SP-A and SP-C were observed with 9-cis-retinoic acid. A retinoic acid response element consensus sequence was identified in the rat SP-A gene; we hypothesize that retinoic acid-receptor complexes act directly on the SP-A gene via this response element.
视黄酸对基因表达具有早期或即时（数小时内）以及晚期（数天后）效应。我们研究了视黄酸对表面活性蛋白（SP）基因的早期效应。将胎鼠肺组织外植体暴露于全反式视黄酸4小时，导致SP-A、-B和-C mRNA显著的剂量依赖性增加，且具有明显不同的剂量反应特征。用10^(-10) M视黄酸处理时，观察到SP-A mRNA最大增加（2.5倍），而用10^(-5) M处理则导致水平有下降趋势。相比之下，在10^(-5) M视黄酸时观察到SP-C的最大刺激（6倍），在10^(-7)至10^(-5) M视黄酸时观察到SP-B的最大刺激（2倍）。用9-顺式视黄酸处理时，观察到SP-A和SP-C剂量反应特征存在类似差异。在大鼠SP-A基因中鉴定出一个视黄酸反应元件共有序列；我们推测视黄酸-受体复合物通过该反应元件直接作用于SP-A基因。
