Tolunay H E, Yang L, Kemper W M, Safer B, Anderson W F
Mol Cell Biol. 1984 Jan;4(1):17-22. doi: 10.1128/mcb.4.1.17-22.1984.
Mouse erythroleukemia (MEL) cells provide a useful model system to examine the regulation of globin gene expression. MEL cells ordinarily do not express globin genes, but in the presence of inducers, such as dimethyl sulfoxide or hexamethylene bisacetamide, they mimic erythroid differentiation. We have developed a cell-free transcription system from uninduced MEL cells to determine the requirements for mRNA synthesis. The MEL system directs accurate transcription of adenovirus type 2 major late DNA and mouse betamaj-globin with an efficiency comparable to those of HeLa and KB cell extracts. Using the procedure of Matsui et al. (T. Matsui, J. Segall, P.A. Weil, and R.G. Roeder, J. Biol. Chem. 255:11992-11996, 1980), we have isolated three active fractions from both MEL and HeLa cell extracts which are required for accurate transcription and have shown that equivalent fractions from MEL and HeLa cell extracts are interchangeable. Our findings suggest that the components required for initiation of transcription are similar in different cell types, at least to the extent that they can be assayed in these in vitro systems.
小鼠红白血病（MEL）细胞为研究珠蛋白基因表达的调控提供了一个有用的模型系统。MEL细胞通常不表达珠蛋白基因，但在存在诱导剂（如二甲基亚砜或六亚甲基双乙酰胺）的情况下，它们会模拟红细胞分化。我们从未诱导的MEL细胞中开发了一种无细胞转录系统，以确定mRNA合成的需求。MEL系统指导腺病毒2型主要晚期DNA和小鼠β-珠蛋白的准确转录，其效率与HeLa和KB细胞提取物相当。使用Matsui等人（T. Matsui、J. Segall、P.A. Weil和R.G. Roeder，《生物化学杂志》255:11992 - 11996，1980）的方法，我们从MEL和HeLa细胞提取物中分离出了三个活性组分，它们是准确转录所必需的，并且已表明MEL和HeLa细胞提取物中的等效组分是可互换的。我们的研究结果表明，不同细胞类型中转录起始所需的组分相似，至少在这些体外系统中可以检测到的程度上是相似的。
