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bioRxiv · 10.1101/2024.12.24.630259

SHEN-LONG, a novel cardiac regulatory locus, regulates cardiac master transcription factor NKX2-5 in pluripotent stem cell derived cardiomyocytes

Scarafia, M. A.·Halek, J.·Smucler, J.·Waisman, A.·Moro, L.·Sevlever, G.·Miriuka, S.·La Greca, A.
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Abstract

Cardiac development is a finely regulated process, transforming undifferentiated cells into the specialized cell components of the heart. Super-Enhancers (SE), clusters of enhancers densely populated with transcription factors, play a central role in cell fate decisions, including cardiogenesis. In this work, we studied a cardiac SE in chr3q25.31. This locus also contains a cardiac specific long non-coding RNA: LINC00881 (LINC881). We termed this region of interest SHEN-LONG (Super Heart ENhancer and LONG non-coding LINC881), and selected it for further functional characterization. Our analysis revealed SHEN-LONG is a hotspot of cardiac kernel transcription factor binding sites. Cardiac differentiation of human iPSC with partial Knock Out of SHEN-LONG resulted in cardiomyocytes with reduced NKX2-5 expression, a master cardiac transcription factor, suggesting a significant role of SHEN-LONG in this process. Whole transcriptome sequencing of SHEN-LONG KO cardiomyocytes produced 134 differentially expressed genes located at great distances (>4Mb) emphasizing its long-range functional impact. A regulation mediated essentially by the SE and not by LINC881 was confirmed when LINC881 overexpression did not recover NKX2-5 expression. These findings provide insights into a novel NKX2-5 regulatory mechanism. The knowledge gained in this work may pave the way for advances in therapeutic interventions for cardiovascular disorders.

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Scarafia, M. A., Halek, J., Smucler, J., Waisman, A., Moro, L., Sevlever, G., Miriuka, S., La Greca, A.. 2024-12-24. SHEN-LONG, a novel cardiac regulatory locus, regulates cardiac master transcription factor NKX2-5 in pluripotent stem cell derived cardiomyocytes. https://doi.org/10.1101/2024.12.24.630259

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