Alpha-catenins control cardiomyocyte proliferation by regulating Yap activity.

Abstract

RATIONALE:

Shortly after birth, muscle cells of the mammalian heart lose their ability to divide. Thus, they are unable to effectively replace dying cells in the injured heart. The recent discovery that the transcriptional coactivator Yes-associated protein (Yap) is necessary and sufficient for cardiomyocyte proliferation has gained considerable attention. However, the upstream regulators and signaling pathways that control Yap activity in the heart are poorly understood.

OBJECTIVE:

To investigate the role of α-catenins in the heart using cardiac-specific αE- and αT-catenin double knockout mice.

METHODS AND RESULTS:

We used 2 cardiac-specific Cre transgenes to delete both αE-catenin (Ctnna1) and αT-catenin (Ctnna3) genes either in the perinatal or in the adult heart. Perinatal depletion of α-catenins increased cardiomyocyte number in the postnatal heart. Increased nuclear Yap and the cell cycle regulator cyclin D1 accompanied cardiomyocyte proliferation in the α-catenin double knockout hearts. Fetal genes were increased in the α-catenin double knockout hearts indicating a less mature cardiac gene expression profile. Knockdown of α-catenins in neonatal rat cardiomyocytes also resulted in increased proliferation, which could be blocked by knockdown of Yap. Finally, inactivation of α-catenins in the adult heart using an inducible Cre led to increased nuclear Yap and cardiomyocyte proliferation and improved contractility after myocardial infarction.

CONCLUSIONS:

These studies demonstrate that α-catenins are critical regulators of Yap, a transcriptional coactivator essential for cardiomyocyte proliferation. Furthermore, we provide proof of concept that inhibiting α-catenins might be a useful strategy to promote myocardial regeneration after injury.

• Authors: Jifen Li, Erhe Gao, Alexia Vite, Roslyn Yi, Ludovic Gomez, Steven Goossens, Frans van Roy, Glenn L Radice
• Journal: Circulation research (Circ Res) Vol. 116 Issue 1 Pg. 70-9 (Jan 02 2015) ISSN: 1524-4571 [Electronic] United States
• PMID: 25305307 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't)
• Copyright: © 2014 American Heart Association, Inc.

Chemical References

• Adaptor Proteins, Signal Transducing
• Cell Cycle Proteins
• Phosphoproteins
• YAP-Signaling Proteins
• Yap1 protein, mouse
• alpha Catenin

Topics

• Adaptor Proteins, Signal Transducing (metabolism)
• Animals
• Animals, Newborn
• Cell Cycle Proteins
• Cell Proliferation (physiology)
• Cells, Cultured
• Mice
• Mice, 129 Strain
• Mice, Inbred C57BL
• Mice, Knockout
• Myocytes, Cardiac (metabolism)
• Phosphoproteins (metabolism)
• Rats
• YAP-Signaling Proteins
• alpha Catenin (physiology)