Dimitriu Maria A, Arzate-Mejía Rodrigo G, Steg Leonard C, Germain Pierre-Luc, Mansuy Isabelle M
Laboratory of Neuroepigenetics, Department of Health Sciences and Technology, Brain Research Institute, Medical Faculty of the University of Zurich and Institute for Neuroscience, ETH Zurich, Zurich, Switzerland.
Neuroscience Center Zurich, University and ETH Zurich, Zurich, Switzerland.
Sci Rep. 2025 Aug 6;15(1):28672. doi: 10.1038/s41598-025-13316-5.
Genome-wide profiling of DNA-protein interactions in cells can provide important information about mechanisms of gene regulation. Most current methods for genome-wide profiling of DNA-bound proteins such as ChIP-seq and CUT&Tag use conventional IgG antibodies to bind the target protein(s). This limits their applicability to targets with available high affinity and specificity antibodies and prevents their use for other targets. Here we describe NanoTag, an IgG-free method derived from CUT&Tag to profile DNA-protein interactions. NanoTag is based on a fusion between an anti-GFP nanobody and Tn5 transposase that can map GFP-tagged proteins associated with chromatin in a fast, cost-effective and animal-free manner. We used NanoTag to indirectly profile the histone mark H3K4me3 genome-wide via its binding partner TATA box-binding protein-associated factor 3 (TAF3) and the transcription factors Nanog and CTCF in mouse embryonic stem cells (mESCs). NanoTag results show high inter-replicate reproducibility, high signal-to-noise ratio and strong correlation with CUT&Tag datasets, validating its accuracy and reliability. NanoTag provides a novel, flexible and cost-effective IgG-free method to generate high resolution DNA-binding profiles in cells and tissues.
对细胞中DNA-蛋白质相互作用进行全基因组分析可以提供有关基因调控机制的重要信息。目前大多数用于全基因组分析与DNA结合蛋白的方法,如染色质免疫沉淀测序(ChIP-seq)和切割与标记(CUT&Tag),都使用传统的IgG抗体来结合目标蛋白。这限制了它们对具有高亲和力和特异性抗体的目标的适用性,并阻止了它们用于其他目标。在这里,我们描述了NanoTag,一种源自CUT&Tag的无IgG方法,用于分析DNA-蛋白质相互作用。NanoTag基于抗绿色荧光蛋白(GFP)纳米抗体与Tn5转座酶之间的融合,它可以以快速、经济高效且无需动物的方式绘制与染色质相关的GFP标记蛋白。我们使用NanoTag通过其结合伴侣TATA盒结合蛋白相关因子3(TAF3)以及小鼠胚胎干细胞(mESCs)中的转录因子Nanog和CTCF,间接对全基因组范围内的组蛋白标记H3K4me3进行分析。NanoTag的结果显示出高重复间再现性、高信噪比以及与CUT&Tag数据集的强相关性,验证了其准确性和可靠性。NanoTag提供了一种新颖、灵活且经济高效的无IgG方法,用于在细胞和组织中生成高分辨率的DNA结合图谱。