Project description:Cardiac-specific Bag3-P209L transgenic (Tg+) mice develop dilated cardiomyopathy by 12 months of age. The goals of this project are to utilize RNA-sequencing to compare both cardiomyocyte and cardiac fibroblast transcriptomes between aged Bag3-P209L Tg+ and Bag3-WT mice to identify cardiomyocyte and fibroblast specific gene sets that contribute to the functional and morphological changes previously identified in Bag3-P209L Tg+ hearts.
Project description:The central goal of the project is to define, experimentally verify, and systematically annotate pathways of endocrine disruption, as a proof of concept of mapping pathways of toxicity by systems toxicology. Experiments were designed to detect possible genomic heterogeneity and genetic drifts within MCF-7 obtained from ATCC (HTB-22, lot number 59388743, passage 147).
Project description:Congenital heart disease (CHD), the most common human birth defect, often results from disruptions in gene regulatory networks (GRNs) that control cardiac lineage specification and cell type identity during heart development. A conserved core set of cardiac transcription factors (TFs) orchestrates these processes through combinatorial interactions that are cell type-specific and tightly regulated across space and time. However, the genomic enhancer architecture that integrates upstream effectors to establish precise cardiac TF dosage and downstream transcriptional output remains largely unresolved. Here, we assessed the functional necessity of five developmental heart enhancer modules previously linked to the regulation of Gata4 and Hand2, core cardiac TFs exhibiting overlapping roles in myocardial and endocardial development. While individual enhancer deletions in mouse embryonic hearts revealed a surprising degree of transcriptional resilience, a subset of Gata4 enhancers proved indispensable for embryonic progression in a genetically compromised background. To achieve higher precision in cardiac cell type-specific enhancer prediction, we applied single-nucleus multiome profiling, enabling the delineation of cardiac cistromes underlying heart morphogenesis. By integrating this resource with deep learning applications, site-directed transgenesis, and chromatin conformation modeling, we mapped the cardiac enhancer repertoire and regulatory signatures that orchestrate Hand2 dynamics across distinct cardiac compartments and lineages. Genome editing further revealed an essential role for the Hand2-upstream regulatory interval (H2-URI) in transcriptional control of endocardial lineage effectors and, consequently, trabecular network formation and cardiac cushion patterning. Together our findings highlight substantial resilience in the cis-regulatory architectures governing cardiac TF dynamics and demonstrate that combinatorial integration of upstream lineage identities across modular enhancer landscapes establishes the cardiac cell type-specific programs driving heart morphogenesis. These results advance the reconstruction of cardiac GRNs and enhance the functional interpretation of CHD-associated variants.