title: Notch Inhibition Enhances Cardiac Reprogramming by Increasing MEF2C Transcriptional Activity.
abstract: Conversion of fibroblasts into functional cardiomyocytes represents a potential means of restoring cardiac function after myocardial infarction, but so far this process remains inefficient and little is known about its molecular mechanisms. Here we show that DAPT, a classical Notch inhibitor, enhances the conversion of mouse fibroblasts into induced cardiac-like myocytes by the transcription factors GATA4, HAND2, MEF2C, and TBX5. DAPT cooperates with AKT kinase to further augment this process, resulting in up to 70% conversion efficiency. Moreover, DAPT promotes the acquisition of specific cardiomyocyte features, substantially increasing calcium flux, sarcomere structure, and the number of spontaneously beating cells. Transcriptome analysis shows that DAPT induces genetic programs related to muscle development, differentiation, and excitation-contraction coupling. Mechanistically, DAPT increases binding of the transcription factor MEF2C to the promoter regions of cardiac structural genes. These findings provide mechanistic insights into the reprogramming process and may have important implications for cardiac regeneration therapies.
authors.affiliation: Department of Molecular Biology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA; Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA; Cell Plasticity and Cancer Group, Vall d'Hebron Institute of Oncology (VHIO), c/Natzaret, 115-117, Barcelona 08035, Spain. Electronic address: mabad@vhio.net.
authors.forename: Maria
authors.initials: M
authors.lastname: Abad
authors.affiliation: Department of Molecular Biology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA; Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA.
authors.forename: Hisayuki
authors.initials: H
authors.lastname: Hashimoto
authors.affiliation: Department of Molecular Biology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA; Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA.
authors.forename: Huanyu
authors.initials: H
authors.lastname: Zhou
authors.affiliation: Department of Molecular Biology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA; Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA.
authors.forename: Maria Gabriela
authors.initials: MG
authors.lastname: Morales
authors.affiliation: Department of Clinical Sciences, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA.
authors.forename: Beibei
authors.initials: B
authors.lastname: Chen
authors.affiliation: Department of Molecular Biology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA; Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA.
authors.forename: Rhonda
authors.initials: R
authors.lastname: Bassel-Duby
authors.affiliation: Department of Molecular Biology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA; Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA. Electronic address: eric.olson@utsouthwestern.edu.
authors.forename: Eric N
authors.initials: EN
authors.lastname: Olson
mesh_terms: D000818:Animals; D020013:Calcium Signaling / Q000187:drug effects; D002454:Cell Differentiation; D065150:Cellular Reprogramming / Q000187:drug effects / Q000235:genetics*; D003959:Diamines / Q000494:pharmacology*; D055724:Electrophysiological Phenomena / Q000187:drug effects; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental; D064326:MEF2 Transcription Factors / Q000378:metabolism*; D051379:Mice; D032383:Myocytes, Cardiac / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism*; D051057:Proto-Oncogene Proteins c-akt / Q000235:genetics / Q000378:metabolism; D051880:Receptors, Notch / Q000378:metabolism*; D012518:Sarcomeres / Q000187:drug effects / Q000378:metabolism; D015398:Signal Transduction; D013844:Thiazoles / Q000494:pharmacology*; D015533:Transcriptional Activation; D059467:Transcriptome
chemical_list: C000612000:24-diamino-5-phenylthiazole; D003959:Diamines; D064326:MEF2 Transcription Factors; D051880:Receptors, Notch; D013844:Thiazoles; C514862:Akt1 protein, mouse; D051057:Proto-Oncogene Proteins c-akt
keywords: DAPT; Notch signaling; cardiomyocytes; cell-fate conversion; direct cellular reprogramming; heart regeneration; regenerative medicine; transdifferentiation