ALPK2 Promotes Cardiogenesis in Zebrafish and Human Pluripotent Stem Cells
Peter Hofsteen,
Aaron Mark Robitaille,
Nicholas Strash,
Nathan Palpant,
Randall T. Moon,
Lil Pabon,
Charles E. Murry
Affiliations
Peter Hofsteen
Department of Pathology, School of Medicine, University of Washington, 850 Republican Street, Brotman Building Room 453, Seattle, WA 98109, USA; Center for Cardiovascular Biology, School of Medicine, University of Washington, Seattle, WA 98109, USA; Institute for Stem Cell and Regenerative Medicine, School of Medicine, University of Washington, Seattle, WA 98109, USA; Corresponding author
Aaron Mark Robitaille
Department of Pharmacology, School of Medicine, University of Washington, Seattle, WA 98109, USA; Institute for Stem Cell and Regenerative Medicine, School of Medicine, University of Washington, Seattle, WA 98109, USA
Nicholas Strash
Department of Pathology, School of Medicine, University of Washington, 850 Republican Street, Brotman Building Room 453, Seattle, WA 98109, USA; Center for Cardiovascular Biology, School of Medicine, University of Washington, Seattle, WA 98109, USA; Institute for Stem Cell and Regenerative Medicine, School of Medicine, University of Washington, Seattle, WA 98109, USA
Nathan Palpant
Department of Pathology, School of Medicine, University of Washington, 850 Republican Street, Brotman Building Room 453, Seattle, WA 98109, USA; Center for Cardiovascular Biology, School of Medicine, University of Washington, Seattle, WA 98109, USA; Institute for Stem Cell and Regenerative Medicine, School of Medicine, University of Washington, Seattle, WA 98109, USA
Randall T. Moon
Department of Pharmacology, School of Medicine, University of Washington, Seattle, WA 98109, USA; Institute for Stem Cell and Regenerative Medicine, School of Medicine, University of Washington, Seattle, WA 98109, USA; Howard Hughes Medical Institute, University of Washington, Seattle, WA 98109, USA
Lil Pabon
Department of Pathology, School of Medicine, University of Washington, 850 Republican Street, Brotman Building Room 453, Seattle, WA 98109, USA; Center for Cardiovascular Biology, School of Medicine, University of Washington, Seattle, WA 98109, USA; Institute for Stem Cell and Regenerative Medicine, School of Medicine, University of Washington, Seattle, WA 98109, USA
Charles E. Murry
Department of Pathology, School of Medicine, University of Washington, 850 Republican Street, Brotman Building Room 453, Seattle, WA 98109, USA; Department of Bioengineering, School of Medicine, University of Washington, Seattle, WA 98109, USA; Department of Medicine (Division of Cardiology), School of Medicine, University of Washington, Seattle, WA 98109, USA; Center for Cardiovascular Biology, School of Medicine, University of Washington, Seattle, WA 98109, USA; Institute for Stem Cell and Regenerative Medicine, School of Medicine, University of Washington, Seattle, WA 98109, USA; Corresponding author
Summary: Cardiac development requires coordinated biphasic regulation of the WNT/β-catenin signaling pathway. By intersecting gene expression and loss-of-function siRNA screens we identified Alpha Protein Kinase 2 (ALPK2) as a candidate negative regulator of WNT/β-catenin signaling in cardiogenesis. In differentiating human embryonic stem cells (hESCs), ALPK2 is highly induced as hESCs transition from mesoderm to cardiac progenitors. Using antisense knockdown and CRISPR/Cas9 mutagenesis in hESCs and zebrafish, we demonstrate that ALPK2 promotes cardiac function and cardiomyocyte differentiation. Quantitative phosphoproteomics, protein expression profiling, and β-catenin reporter assays demonstrate that loss of ALPK2 led to stabilization of β-catenin and increased WNT signaling. Furthermore, cardiac defects attributed to ALPK2 depletion can be rescued in a dose-dependent manner by direct inhibition of WNT signaling through the small molecule XAV939. Together, these results demonstrate that ALPK2 regulates β-catenin-dependent signaling during developmental commitment of cardiomyocytes. : Piscine Cardiology; Stem Cell Research; Developmental Biology Subject Areas: Piscine Cardiology, Stem Cell Research, Developmental Biology
