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Wang, X. Q. D.

Publications and source records attributed to Wang, X. Q. D..

2 recordsLinked to original sources

Connecting high-resolution 3D chromatin organization with epigenomics

The resolution of chromatin conformation capture technologies keeps increasing, and the recent nucleosome resolution chromatin contact maps allow us to explore how fine-scale 3D chromatin organization is related to epigenomic states in human cells. Using publicly available Micro-C datasets, we have developed a deep learning model, CAESAR, to learn a mapping function from epigenomic features to 3D chromatin organization. The model accurately predicts fine-scale structures, such as short-range chromatin loops and stripes, that Hi-C fails to detect. With existing epigenomic datasets from ENCODE and Roadmap Epigenomics Project, we successfully imputed high-resolution 3D chromatin contact maps for 91 human tissues and cell lines. In the imputed high-resolution contact maps, we identified the spatial interactions between genes and their experimentally validated regulatory elements, demonstrating CAESARs potential in coupling transcriptional regulation with 3D chromatin organization at high resolution.

bioinformatics

Three-dimensional regulation of HOXA cluster genes by a cis-element in hematopoietic stem cell and leukemia.

Proper gene regulation is crucial for cellular differentiation, and dysregulation of key genes can lead to diseased states such as cancer. The HOX transcription factors play such a role during hematopoiesis, and aberrant expression of certain HOXA genes is found in certain acute myeloid leukemias (AMLs). While studies have shown that these genes are targeted by a variety of mutant proteins including mutant NPM1, MLL fusions, and NUP98 fusions, little is known about how long-range 3D chromatin interactions regulate the HOXA genes in normal hematopoiesis and leukemia. Here, we report the interaction between the HOXA cluster with a [~]1.3 Mb upstream DNA methylation Canyon termed "Geneless Canyon" (GLC) in human CD34+/CD38-hematopoietic stem cells (HSCs) and AML cell lines. We show that CRISPR-Cas9 mediated deletion of the whole GLC region reduces the expression of the distal HOXA genes and compromises HSC and leukemia cells self-renewal. This long-range chromatin interaction brings the HOXA cluster in contact with the nuclear pore complex (NPC) at the nuclear periphery, which promotes HOXA gene expression and maintains HSC and leukemia cell self-renewal. These findings reveal how long-range 3D chromatin organization regulates key transcription factor genes in both normal and diseased hematopoietic cells.

genomics