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bioRxiv · 10.1101/154765

Hippo signaling restricts cells in the second heart field that differentiate into Islet-1-positive atrial cardiomyocytes

Fukui, H.·Miyazaki, T.·Ishikawa, H.·Nakajima, H.·Mochizuki, N.
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Abstract

AbstractCardiac precursor cells (CPCs) in the first heart field (FHF) and the second heart field (SHF) present at both arterial and venous poles assemble to form a cardiac tube in zebrafish. Hippo kinase cascade is essential for proper heart formation; however, it remains elusive how Hippo signal contributes to early cardiac fate determination. We here demonstrate that mutants of large tumor suppressor kinase 1/2 (lats1/2) exhibited an increase in a SHF marker, Islet1 (Isl1)-positive and hand2 promoter-activated venous pole atrial cardiomyocytes (CMs) and that those showed expansion of the domain between between the anterior and the posterior lateral plate mesoderm. Consistently, TEAD-8 dependent transcription was activated in caudal region of the left ALPM cells that gave rise to the venous pole atrial CMs. Yap1/Wwtr1-promoted bmp2b expression was essential for Smad-regulated hand2 expression in the left ALPM, indicating that Hippo signaling restricts the SHF cells originating from the left ALPM that move toward the venous pole.

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Fukui, H., Miyazaki, T., Ishikawa, H., Nakajima, H., Mochizuki, N.. 2017-06-23. Hippo signaling restricts cells in the second heart field that differentiate into Islet-1-positive atrial cardiomyocytes. https://doi.org/10.1101/154765

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