[Investigation of 3D chromatin structures].

Recent studies have revealed that multiple layers of higher-order chromatin architecture are intricately organized within the cell nucleus. While these structures are essential for the proper differentiation and function of hematopoietic cells, their dysregulation has been implicated in pathological conditions, including leukemia. Chromatin conformation capture (3C)-based methods, such as Hi-C, have revolutionized our understanding of chromatin organization and its function. Various innovative approaches have been developed to address the inherent limitations of 3C technologies. Among these, imaging-based techniques derived from fluorescence in situ hybridization, utilizing multiplexed DNA probe sets, have garnered particular attention for enabling multimodal analysis at the single-cell level. Furthermore, live-cell imaging of chromatin interactions using CRISPR-Cas9 technology is being actively developed as a powerful and practical tool. In this review, we outline the mechanisms and biological relevance of major 3D chromatin structures and highlight recent technological advances in chromatin architecture analysis.