Weidle U, Weissmann C
Nature. 1983;303(5916):442-6. doi: 10.1038/303442a0.
Usually only cells exposed to virus, double-stranded RNA or other inducers synthesize interferon (IFN). Interferon mRNA appears 1-2 h after induction, peaks at 1.5-20 h and decays with a half life of about 30 min. So far, it has not been determined whether induction of interferon is due to transient stabilization of a rapidly turning-over mRNA or to activation of transcription. To clarify this issue we transformed mouse L cells with a hybrid gene in which the 5'-flanking region of the human IFN-alpha 1 gene was followed by the rabbit beta-globin transcription unit. Correctly initiated beta-globin RNA appeared only after viral induction, with the kinetics described for interferon mRNA. Cells transformed with the converse construction, or with the complete rabbit beta-globin gene, constitutively produced correctly initiated transcripts; viral infection decreased the level of transcripts. We conclude that induction acts by activating transcription rather than by reducing turnover, and that the regulatory elements are contained in the 5'-flanking region of the interferon gene.
通常只有暴露于病毒、双链RNA或其他诱导剂的细胞才会合成干扰素（IFN）。干扰素mRNA在诱导后1 - 2小时出现，在1.5 - 20小时达到峰值，并以约30分钟的半衰期衰减。到目前为止，尚未确定干扰素的诱导是由于快速周转的mRNA的瞬时稳定还是转录激活。为了阐明这个问题，我们用一个杂交基因转化小鼠L细胞，该杂交基因中人类IFN-α1基因的5'侧翼区域后面跟着兔β-珠蛋白转录单位。正确起始的β-珠蛋白RNA仅在病毒诱导后出现，其动力学与干扰素mRNA描述的相同。用相反构建体或完整的兔β-珠蛋白基因转化的细胞组成性地产生正确起始的转录本；病毒感染降低了转录本水平。我们得出结论，诱导是通过激活转录而不是通过减少周转来起作用的，并且调节元件包含在干扰素基因的5'侧翼区域中。
