Gartner Hans, Shukla Pramila, Markesich Diane C, Solomon Nitikul S, Oesterreicher Thomas J, Henning Susan J
Department of Pediatrics, Baylor College of Medicine, One Baylor College of Medicine, Houston, TX 77030, USA.
Biochim Biophys Acta. 2002 Apr 12;1574(3):329-36. doi: 10.1016/s0167-4781(02)00231-2.
The third postnatal week of mouse development is characterized by dramatic changes of gene expression in the small intestine. Although these changes are often assumed to reflect regulation at the level of transcription, to date there have been no direct investigations of this. In the current study we have used trehalase as a marker of intestinal maturation. Highly sensitive reverse transcriptase-polymerase chain reaction methods were developed for semi-quantitative analysis of both initial and mature transcripts, i.e., hnRNA and mRNA. Jejunums collected during normal development (specifically from postnatal days 8-21) showed parallel increases in the levels of trehalase hnRNA and mRNA. Likewise, when precocious gut maturation was elicited by dexamethasone administration on days 8-10, both initial and mature trehalase transcripts were significantly increased, although with a relatively slow time course. We conclude that both normal and glucocorticoid-induced maturation of trehalase expression reflect transcriptional activation. However, the slow time course of the glucocorticoid effect suggests that trehalase may not be a primary response gene.
小鼠发育的出生后第三周，小肠中的基因表达会发生显著变化。尽管这些变化通常被认为反映了转录水平的调控，但迄今为止尚未对此进行直接研究。在当前研究中，我们使用海藻糖酶作为肠道成熟的标志物。我们开发了高度灵敏的逆转录聚合酶链反应方法，用于对初始转录本和成熟转录本（即核不均一RNA和信使RNA）进行半定量分析。在正常发育过程中（具体为出生后第8至21天）收集的空肠显示，海藻糖酶核不均一RNA和信使RNA的水平平行增加。同样，当在第8至10天通过给予地塞米松引发早熟肠道成熟时，初始和成熟的海藻糖酶转录本均显著增加，尽管时间进程相对较慢。我们得出结论，海藻糖酶表达的正常成熟和糖皮质激素诱导的成熟均反映了转录激活。然而，糖皮质激素效应的缓慢时间进程表明，海藻糖酶可能不是一个初级反应基因。
