Sehgal P B, May L T, LaForge K S, Inouye M
Proc Natl Acad Sci U S A. 1982 Nov;79(22):6932-6. doi: 10.1073/pnas.79.22.6932.
Each of the several intronless interferon (IFN) alpha S genes is embedded in 4- to 5-kilobase (kb) DNA homology units which are arranged more or less in tandem in the human genome. In addition to the expected 0.8- to 1.4-kb-long IFN-alpha S mRNA species, we have detected polyadenylylated RNA molecules approximately 2-2.7, 3.5-4.5, and 7-8 kb long derived from IFN-alpha S genes in the cytoplasm of Sendai virus-induced bromodeoxyuridine-treated human lymphoblastoid (Namalwa) cells. These transcripts were detected by electrophoresis of cytoplasmic polyadenylylated RNA through agarose-CH3HgOH gels followed by blothybridization using an IFN-alpha 1 (a prototype alpha S) cDNA probe and also by translation of the eluted RNA into biologically active IFN in the Xenopus oocyte assay. At least some of these long translationally active RNA molecules appear to represent functional mRNA species because they can be detected in polysomes. In addition, the oocyte translation assay has revealed the presence of unusually long (2-8 kb) IFN-beta mRNA species both in Sendai virus-induced Namalwa cells and in poly(I) . poly(C)-induced diploid human fibroblasts (FS-4). The detection of very long IFN-alpha 1-related mRNA species suggests that some of the DNA sequence features observed in the flanking homology units may affect the transcription of the IFN-alpha S genes. Our hybridization analyses also indicate that the 1.8-kb human IFN-alpha L mRNA(s) shows no detectable cross-hybridization with an IFN-alpha 1 cDNA probe. Thus, this mRNA is derived from a gene(s) that is distinct from the IFN-alpha S set.
几个无内含子的干扰素（IFN）αS基因中的每一个都嵌入在4至5千碱基（kb）的DNA同源单位中，这些单位在人类基因组中或多或少地串联排列。除了预期的0.8至1.4 kb长的IFN-αS mRNA种类外，我们还在仙台病毒诱导的经溴脱氧尿苷处理的人淋巴母细胞（Namalwa）细胞质中检测到了源自IFN-αS基因的约2 - 2.7、3.5 - 4.5和7 - 8 kb长的多聚腺苷酸化RNA分子。这些转录本通过将细胞质多聚腺苷酸化RNA在琼脂糖 - 甲基汞凝胶上进行电泳，然后使用IFN-α1（αS原型）cDNA探针进行斑点杂交来检测，也通过在非洲爪蟾卵母细胞试验中将洗脱的RNA翻译成生物活性IFN来检测。这些长的具有翻译活性的RNA分子中至少有一些似乎代表功能性mRNA种类，因为它们可以在多核糖体中被检测到。此外，卵母细胞翻译试验揭示了在仙台病毒诱导的Namalwa细胞以及聚肌苷酸 - 聚胞苷酸（poly(I)·poly(C)）诱导的二倍体人成纤维细胞（FS - 4）中都存在异常长（2 - 8 kb）的IFN-β mRNA种类。检测到非常长的与IFN-α1相关的mRNA种类表明，在侧翼同源单位中观察到的一些DNA序列特征可能会影响IFN-αS基因的转录。我们的杂交分析还表明，1.8 kb的人IFN-αL mRNA与IFN-α1 cDNA探针没有可检测到的交叉杂交。因此，这种mRNA来自与IFN-αS基因集不同的基因。
