[HTML][HTML] Global chromatin landscapes identify candidate noncoding modifiers of cardiac rhythm

S Bhattacharyya, RK Kollipara… - The Journal of …, 2023 - Am Soc Clin Investig
S Bhattacharyya, RK Kollipara, G Orquera-Tornakian, S Goetsch, M Zhang, C Perry, B Li
The Journal of clinical investigation, 2023Am Soc Clin Investig
Comprehensive cis-regulatory landscapes are essential for accurate enhancer prediction
and disease variant mapping. Although cis-regulatory element (CRE) resources exist for
most tissues and organs, many rare—yet functionally important—cell types remain
overlooked. Despite representing only a small fraction of the heart's cellular biomass, the
cardiac conduction system (CCS) unfailingly coordinates every life-sustaining heartbeat. To
globally profile the mouse CCS cis-regulatory landscape, we genetically tagged CCS …
Comprehensive cis-regulatory landscapes are essential for accurate enhancer prediction and disease variant mapping. Although cis-regulatory element (CRE) resources exist for most tissues and organs, many rare — yet functionally important — cell types remain overlooked. Despite representing only a small fraction of the heart’s cellular biomass, the cardiac conduction system (CCS) unfailingly coordinates every life-sustaining heartbeat. To globally profile the mouse CCS cis-regulatory landscape, we genetically tagged CCS component–specific nuclei for comprehensive assay for transposase-accessible chromatin–sequencing (ATAC-Seq) analysis. Thus, we established a global CCS-enriched CRE database, referred to as CCS-ATAC, as a key resource for studying CCS-wide and component-specific regulatory functions. Using transcription factor (TF) motifs to construct CCS component–specific gene regulatory networks (GRNs), we identified and independently confirmed several specific TF sub-networks. Highlighting the functional importance of CCS-ATAC, we also validated numerous CCS-enriched enhancer elements and suggested gene targets based on CCS single–cell RNA-Seq data. Furthermore, we leveraged CCS-ATAC to improve annotation of existing human variants related to cardiac rhythm and nominated a potential enhancer-target pair that was dysregulated by a specific SNP. Collectively, our results established a CCS-regulatory compendium, identified novel CCS enhancer elements, and illuminated potential functional associations between human genomic variants and CCS component–specific CREs.
The Journal of Clinical Investigation