title: Transcriptome-guided functional analyses reveal novel biological properties and regulatory hierarchy of human embryonic stem cell-derived ventricular cardiomyocytes crucial for maturation.
abstract: Human (h) embryonic stem cells (ESC) represent an unlimited source of cardiomyocytes (CMs); however, these differentiated cells are immature. Thus far, gene profiling studies have been performed with non-purified or non-chamber specific CMs. Here we took a combinatorial approach of using systems biology to guide functional discoveries of novel biological properties of purified hESC-derived ventricular (V) CMs. We profiled the transcriptomes of hESCs, hESC-, fetal (hF) and adult (hA) VCMs, and showed that hESC-VCMs displayed a unique transcriptomic signature. Not only did a detailed comparison between hESC-VCMs and hF-VCMs confirm known expression changes in metabolic and contractile genes, it further revealed novel differences in genes associated with reactive oxygen species (ROS) metabolism, migration and cell cycle, as well as potassium and calcium ion transport. Following these guides, we functionally confirmed that hESC-VCMs expressed IKATP with immature properties, and were accordingly vulnerable to hypoxia/reoxygenation-induced apoptosis. For mechanistic insights, our coexpression and promoter analyses uncovered a novel transcriptional hierarchy involving select transcription factors (GATA4, HAND1, NKX2.5, PPARGC1A and TCF8), and genes involved in contraction, calcium homeostasis and metabolism. These data highlight novel expression and functional differences between hESC-VCMs and their fetal counterparts, and offer insights into the underlying cell developmental state. These findings may lead to mechanism-based methods for in vitro driven maturation.
authors.affiliation: Stem Cell & Regenerative Medicine Consortium, LKS Faculty of Medicine, University of Hong Kong, Hong Kong, China.
authors.forename: Ellen
authors.initials: E
authors.lastname: Poon
authors.forename: Bin
authors.initials: B
authors.lastname: Yan
authors.forename: Shaohong
authors.initials: S
authors.lastname: Zhang
authors.forename: Stephanie
authors.initials: S
authors.lastname: Rushing
authors.forename: Wendy
authors.initials: W
authors.lastname: Keung
authors.forename: Lihuan
authors.initials: L
authors.lastname: Ren
authors.forename: Deborah K
authors.initials: DK
authors.lastname: Lieu
authors.forename: Lin
authors.initials: L
authors.lastname: Geng
authors.forename: Chi-Wing
authors.initials: CW
authors.lastname: Kong
authors.forename: Jiaxian
authors.initials: J
authors.lastname: Wang
authors.forename: Hau San
authors.initials: HS
authors.lastname: Wong
authors.forename: Kenneth R
authors.initials: KR
authors.lastname: Boheler
authors.forename: Ronald A
authors.initials: RA
authors.lastname: Li
mesh_terms: D000328:Adult; D000818:Animals; D015415:Biomarkers / Q000378:metabolism*; D002454:Cell Differentiation; D049109:Cell Proliferation; D004594:Electrophysiology; D053595:Embryonic Stem Cells / Q000166:cytology / Q000378:metabolism*; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental; D053263:Gene Regulatory Networks; D006352:Heart Ventricles / Q000196:embryology / Q000378:metabolism*; D006801:Humans; D051379:Mice; D032383:Myocytes, Cardiac / Q000166:cytology / Q000378:metabolism*; D020411:Oligonucleotide Array Sequence Analysis; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D015415:Biomarkers; D012333:RNA, Messenger