Loss of Asb2 Impairs Cardiomyocyte Differentiation and Leads to Congenital Double Outlet Right Ventricle

  • iScience. 2020 Mar 27;23(3):100959. doi: 10.1016/j.isci.2020.100959.
Abir Yamak  1 ,  Dongjian Hu  2 ,  Nikhil Mittal  3 ,  Jan W Buikema  4 ,  Sheraz Ditta  5 ,  Pierre G Lutz  6 ,  Christel Moog-Lutz  6 ,  Patrick T Ellinor  7 ,  Ibrahim J Domian  8
Affiliations
  • 1. Harvard Medical School, Boston, MA 02115, USA; Cardiovascular Research Center, Massachusetts General Hospital, 185 Cambridge Street, CPZN3200, Boston, MA 02114, USA; Cardiovascular Disease Initiative, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA. Electronic address: [email protected].
  • 2. Cardiovascular Research Center, Massachusetts General Hospital, 185 Cambridge Street, CPZN3200, Boston, MA 02114, USA; Department of Biomedical Engineering, Boston University, Boston, MA 02215, USA.
  • 3. Harvard Medical School, Boston, MA 02115, USA; Cardiovascular Research Center, Massachusetts General Hospital, 185 Cambridge Street, CPZN3200, Boston, MA 02114, USA.
  • 4. Cardiovascular Research Center, Massachusetts General Hospital, 185 Cambridge Street, CPZN3200, Boston, MA 02114, USA; University Medical Center Utrecht, 3584 CX Utrecht, Netherlands.
  • 5. Cardiovascular Research Center, Massachusetts General Hospital, 185 Cambridge Street, CPZN3200, Boston, MA 02114, USA; Department of Pharmaceutical Sciences, Utrecht University, 3512 JE Utrecht, Netherlands.
  • 6. Institut de Pharmacologie et de Biologie Structurale, IPBS, Université de Toulouse, CNRS, UPS, Toulouse, France.
  • 7. Harvard Medical School, Boston, MA 02115, USA; Cardiovascular Research Center, Massachusetts General Hospital, 185 Cambridge Street, CPZN3200, Boston, MA 02114, USA; Cardiovascular Disease Initiative, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA.
  • 8. Harvard Medical School, Boston, MA 02115, USA; Cardiovascular Research Center, Massachusetts General Hospital, 185 Cambridge Street, CPZN3200, Boston, MA 02114, USA; Harvard Stem Cell Institute, Cambridge, MA 02138, USA. Electronic address: [email protected].
PMID: 32179481 DOI: 10.1016/j.isci.2020.100959
Abstract

Defining the pathways that control cardiac development facilitates understanding the pathogenesis of congenital heart disease. Herein, we identify enrichment of a Cullin5 Ub Ligase key subunit, Asb2, in myocardial progenitors and differentiated cardiomyocytes. Using two conditional murine knockouts, Nkx+/Cre.Asb2fl/fl and AHF-Cre.Asb2fl/fl, and tissue clarifying technique, we reveal Asb2 requirement for embryonic survival and complete heart looping. Deletion of Asb2 results in upregulation of its target Filamin A (Flna), and concurrent Flna deletion partially rescues embryonic lethality. Conditional AHF-Cre.Asb2 knockouts harboring one Flna allele have double outlet right ventricle (DORV), which is rescued by biallelic Flna excision. Transcriptomic and immunofluorescence analyses identify Tgfβ/Smad as downstream targets of Asb2/Flna. Finally, using CRISPR/Cas9 genome editing, we demonstrate Asb2 requirement for human cardiomyocyte differentiation suggesting a conserved mechanism between mice and humans. Collectively, our study provides deeper mechanistic understanding of the role of the ubiquitin Proteasome system in cardiac development and suggests a previously unidentified murine model for DORV.

Keywords
Biological Sciences; Developmental Biology; Molecular Biology.