Abstract P2044: The Cardioprotective Egr-1 And Maladaptive Sp-1 Zinc Finger Transcription Factor Reciprocally Regulates Expression Of The Cardiomyocyte Performance Enhancing Protein S100a1

• DOI: 10.1161/res.131.suppl_1.p2044
• Publication Date: 2022-11-14T14:52:03Z
• Authors: Martin Busch; Thien-Kim Bui; Lukas Adrian; Fabian Guenther; Mandy Rettel; Frank Stein; Jan Haas; Hagen Klett; Melanie Boerries; Benjamin Meder; Christoph Dieterich; Hugo A Katus; Patrick Most
• Keywords: 03 medical and health sciences; 0302 clinical medicine

Background and Hypothesis: Expression of the cardiomyocyte (CM) protein S100A1, which improves contractile performance heart, sharply increases during postnatal myocardial maturation but declines rapidly in failing hearts. We therefore hypothesized that CMs are wired with transcriptional factors (TFs) positively negatively regulate S100A1’s gene locus activity. Understanding these reciprocal circuits may be relevant for advanced therapeutic modulation abundance diseased Methods Results: H9C2 rat cardiomyoblasts, an animal-free vitro tool, displayed a strong concordant rise S100A1 mRNA levels (8.1+/-1.1 vs. cont.; n=9, p<0.05) amongst other CM markers (i.e., SERCA2a) over 5-day differentiation protocol. Overall TF activity this process was computationally inferred from binding site (TFBS) assessments promoters all actively regulated transcripts provided by time-resolved (undifferentiated, day 0, 2 5) transcriptome analysis. From TFs, EGR1 SP1 eight others were chosen due to their both differentiated H9C2-CMs adult hearts TFBS -1000 +500 bp promoter region 5’ RACE-PCR based transcription start identification our model. To capture TFs group, we next co-incubated nuclear extracts biotinylated fragments aforementioned coupled streptavidin beads. promoter-bound identified mass spectrometry only >2-fold enrichment control selected delivering as top hits. Subsequent siRNA-mediated silencing yielded knock-down dose-dependent inhibition (80%; p<0.05 contr., n=9) amplification (126%; H9C2-CM model validated comp./exp. pipeline biological relevance hits, respectively. Conclusion: Our study known cardioprotective maladaptive novel positive negative regulators expression targets i.e., gene-editing.