Multiple studies in Saccharomyces cerevisiae have measured the levels of gene silencing by inserting the URA3 gene at various loci and selecting against URA3-expressing cells by 5-flouroorotic acid (5-FOA). However, 5-FOA affects the cellular pools of dNTPs and can produce side effects. To circumvent this issue, we and others have introduced drug-free techniques to detect silent and active gene states. In this study, we compared three drug-free methods based on the expression of fluorescent reporters in the VIIL telomere of S. cerevisiae. Our results point out that only one of these methods is suitable for large-scale drug-free analyses of gene silencing.

中文翻译：

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用于检测酿酒酵母基因沉默的无药物方法的评价。

酿酒酵母中的多项研究通过在不同位点插入 URA3 基因并通过 5-氟乳清酸 (5-FOA) 选择表达 URA3 的细胞来测量基因沉默的水平。然而，5-FOA 会影响 dNTP 的细胞库并会产生副作用。为了规避这个问题，我们和其他人引入了无药物技术来检测沉默和活跃的基因状态。在这项研究中，我们比较了三种基于荧光报告基因在酿酒酵母 VIIL 端粒中表达的无药物方法。我们的结果指出，这些方法中只有一种适用于基因沉默的大规模无药物分析。