Abstract 13841: Transcriptomic Signatures of Atrial- And Ventricular-like Human Induced Pluripotent Stem Cell Derived Cardiomyocytes
Differentiation of cardiomyocytes from human induced pluripotent stem cells (hiPSC-CMs) can be used to gain insight into the signaling pathways that regulate human heart development. The resulting hiPSC-CMs formed have been reported to possess either atrial- or ventricular-like characteristics and uncovering the molecular mechanisms which regulate the development of these cardiomyocyte subtypes will be instrumental in drug screening and disease modelling research efforts. To investigate the molecular signatures of atrial- and/or ventricular-like hiPSC-CMs formed after differentiation, we profiled the transcriptomic signatures of day 30 hiPSC-CMs using single-cell RNA-seq. Using unsupervised and supervised clustering approaches, we defined distinct subpopulations of hiPSC-CMs representing different stages of maturity as well as expressing atrial or ventricular markers. Expression of NR2F2 was found to be specifically enriched within the atrial defined subpopulation while HEY2 expression was enriched within the ventricular defined subpopulation. To further investigate the role that these transcription factors play in defining each cardiomyocyte subpopulation, we created cell lines deficient in either HEY2 or NR2F2 using CRISPR technology. Patch-clamp analysis revealed an increase in atrial-like action potentials within HEY2 gene-edited cardiomyocytes and single cell Westerns revealed a decrease in the expression of the ventricular marker MYL2 within these cells. Finally, by assessing the temporal expression of transcription factors during differentiation by RNA-seq (along with CyTOF analysis), we observed that the expression of atrial markers preceded the expression of ventricular markers. By defining the transcriptomic signatures of cardiomyocyte subpopulations using single-cell RNA-seq and additional novel supporting methods, we provide a platform for understanding human heart developmental pathways in vitro, hiPSC-CM heterogeneity, and cardiomyocyte subtype specificity.
Author Disclosures: J. Churko: None. B. Treutlein: None. P. Garg: None. M. Venkatasubramanian: None. H. Wu: None. S. Chen: None. W. Chen: None. J. Lee: None. V. Termglinchan: None. G. Mantalas: None. N. Neff: None. E. Jabart: None. G. Nolan: None. N. Salomonis: None. J. Wu: None.
- © 2016 by American Heart Association, Inc.