The main transcriptional regulator of leucine biosynthesis in the yeast Saccharomyces cerevisiae is the transcription factor Leu3. It has previously been reported that Leu3 always binds to its target genes but requires activation to induce their expression. In a recent large-scale study of high-resolution transcription factor binding site identification, we showed that Leu3 has divergent binding sites in different cultivation conditions, thereby questioning the results of earlier studies. Here we present a follow up study using chromatin immunoprecipitation followed by sequencing (ChIP-seq) to investigate the influence of leucine supplementation on Leu3 binding activity and strength. With this new data set we are able to show that Leu3 exhibits changes in binding activity in response to changing levels of leucine availability.

中文翻译：

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转录因子 Leu3 显示出不同的结合行为，以响应不断变化的亮氨酸可用性。

酿酒酵母中亮氨酸生物合成的主要转录调节因子是转录因子 Leu3。此前有报道称，Leu3 总是与其靶基因结合，但需要激活才能诱导它们的表达。在最近一项高分辨率转录因子结合位点鉴定的大规模研究中，我们发现 Leu3 在不同培养条件下具有不同的结合位点，从而质疑早期研究的结果。在这里，我们使用染色质免疫沉淀和测序 (ChIP-seq) 进行后续研究，以研究补充亮氨酸对 Leu3 结合活性和强度的影响。有了这个新的数据集，我们能够证明 Leu3 表现出结合活性的变化，以响应亮氨酸可用性水平的变化。