Department of Biological Sciences, Columbia University, New York, NY 10027, USA.
Proc Natl Acad Sci U S A. 2012 Apr 17;109(16):6030-5. doi: 10.1073/pnas.1203028109. Epub 2012 Mar 29.
TLS/FUS (TLS) is a multifunctional protein implicated in a wide range of cellular processes, including transcription and mRNA processing, as well as in both cancer and neurological disease. However, little is currently known about TLS target genes and how they are recognized. Here, we used ChIP and promoter microarrays to identify genes potentially regulated by TLS. Among these genes, we detected a number that correlate with previously known functions of TLS, and confirmed TLS occupancy at several of them by ChIP. We also detected changes in mRNA levels of these target genes in cells where TLS levels were altered, indicative of both activation and repression. Next, we used data from the microarray and computational methods to determine whether specific sequences were enriched in DNA fragments bound by TLS. This analysis suggested the existence of TLS response elements, and we show that purified TLS indeed binds these sequences with specificity in vitro. Remarkably, however, TLS binds only single-strand versions of the sequences. Taken together, our results indicate that TLS regulates expression of specific target genes, likely via recognition of specific single-stranded DNA sequences located within their promoter regions.
TLS/FUS (TLS) 是一种多功能蛋白，涉及多种细胞过程，包括转录和 mRNA 处理，以及癌症和神经疾病。然而，目前对于 TLS 的靶基因及其识别方式知之甚少。在这里，我们使用 ChIP 和启动子微阵列来鉴定可能受 TLS 调控的基因。在这些基因中，我们检测到一些与 TLS 已知功能相关的基因，并通过 ChIP 证实了它们中的几个基因的 TLS 占据。我们还检测到在 TLS 水平改变的细胞中这些靶基因的 mRNA 水平发生变化，表明存在激活和抑制作用。接下来，我们使用微阵列和计算方法的数据来确定 DNA 片段中是否存在与 TLS 结合的特定序列。该分析表明存在 TLS 反应元件，我们证明纯化的 TLS 确实可以特异性地在体外结合这些序列。然而，令人惊讶的是，TLS 仅结合这些序列的单链版本。总之，我们的结果表明，TLS 通过识别位于其启动子区域内的特定单链 DNA 序列来调节特定靶基因的表达。
