Transcription factors (TFs) are life-sustaining and, therefore, the subject of intensive research. By regulating gene expression, TFs control a plethora of developmental and physiological processes, and their abnormal function commonly leads to various developmental defects and diseases in humans. Normal TF function often depends on gene dosage, which can be altered by copy-number variation or loss-of-function mutations. This explains why TF haploinsufficiency (HI) can lead to disease. Since aberrant TF numbers frequently result in pathogenic abnormalities of gene expression, quantitative analyses of TFs are a priority in the field. In vitro single-molecule methodologies have significantly aided the identification of links between TF gene dosage and transcriptional outcomes. Additionally, advances in quantitative microscopy have contributed mechanistic insights into normal and aberrant TF function. However, to understand TF biology, TF-chromatin interactions must be characterised in vivo, in a tissue-specific manner and in the context of both normal and altered TF numbers. Here, we summarise the advanced microscopy methodologies most frequently used to link TF abundance to function and dissect the molecular mechanisms underlying TF HIs. Increased application of advanced single-molecule and super-resolution microscopy modalities will improve our understanding of how TF HIs drive disease.

中文翻译：

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数字和运动 - 通过先进的显微镜了解转录因子发病机制。


转录因子 (TF) 是维持生命的因子，因此是深入研究的主题。通过调节基因表达，转录因子控制着大量的发育和生理过程，其功能异常通常会导致人类的各种发育缺陷和疾病。正常的转录因子功能通常取决于基因剂量，而基因剂量可以通过拷贝数变异或功能丧失突变来改变。这解释了为什么 TF 单倍体不足 (HI) 会导致疾病。由于异常的 TF 数量经常导致基因表达的致病性异常，因此 TF 的定量分析是该领域的优先事项。体外单分子方法极大地帮助识别 TF 基因剂量和转录结果之间的联系。此外，定量显微镜技术的进步也为我们对正常和异常的转录因子功能的机制提供了深入的了解。然而，为了了解 TF 生物学，必须在正常和改变的 TF 数量的背景下，以组织特异性方式在体内表征 TF-染色质相互作用。在这里，我们总结了最常用于将 TF 丰度与功能联系起来的先进显微镜方法，并剖析了 TF HI 背后的分子机制。先进单分子和超分辨率显微镜模式的更多应用将提高我们对 TF HI 如何驱动疾病的理解。