Mechanical Forces Regulate Cardiomyocyte Myofilament Maturation via the VCL-SSH1-CFL Axis

Area of Science:

• Cardiovascular Biology
• Cellular Mechanotransduction
• Muscle Development

Background:

• Mechanical forces are crucial for tissue development and cell function.
• Cardiac development relies on mechanical stimuli from heartbeats for cardiomyocyte maturation.
• The molecular mechanisms linking mechanical forces to cardiomyocyte maturation are not fully understood.

Purpose of the Study:

• To elucidate the molecular mechanisms by which mechanical forces regulate cardiomyocyte maturation.
• To investigate the role of vinculin (VCL) in response to cardiac mechanical forces.
• To identify key protein interactions and pathways involved in force transmission for myofilament development.

Main Methods:

• Analysis of vinculin (VCL) localization and activation in response to cardiac forces.
• Interactome studies comparing contracting and non-contracting cardiomyocytes.
• Investigation of the VCL-SSH1-cofilin (CFL) axis in regulating F-actin dynamics.

Main Results:

• Cardiac contractility regulates the localization and activation of vinculin (VCL).
• Vinculin (VCL) is essential for myofilament maturation in cardiomyocytes.
• VCL recruits slingshot protein phosphatase 1 (SSH1) and cofilin (CFL) to regulate F-actin rearrangement, promoting myofilament maturation.

Conclusions:

• Mechanical forces from cardiac contractility regulate cardiomyocyte maturation via the VCL-SSH1-CFL pathway.
• This study reveals a novel mechanism for intracellular force transmission in cardiomyocytes.
• Understanding this axis provides critical insights into cardiac development and mechanobiology.