Engineering filamentous myosins for optical control of contractility

Area of Science:

• Biophysics
• Cell Biology
• Molecular Motors

Background:

• Actomyosin contractility is crucial for cellular functions.
• Precise control over myosin activity is needed to understand these systems.
• Existing methods lack spatiotemporal precision.

Purpose of the Study:

• To develop a tool for optical control of actomyosin contractility.
• To engineer filamentous myosins with light-responsive velocity.
• To investigate the behavior and applications of these engineered myosins.

Main Methods:

• Engineering MyLOV-based gearshifting motors.
• In vitro single-molecule tracking assays.
• Contractility assays in reconstituted actin networks.
• Imaging contractile phenotypes in Drosophila S2 cells.

Main Results:

• Engineered minifilaments change speed and/or direction upon blue light illumination.
• Minifilaments exhibit physiologically relevant speeds and high processivity.
• Blue light increases minifilament-driven contraction rates in vitro and in cells.
• An alternative design shows light-dependent processive interaction with actin.

Conclusions:

• Light-inducible engineered myosins provide precise spatiotemporal control over contractility.
• These tools enable dissection of self-organization and mechanotransduction.
• The engineered minifilaments are applicable in vitro and in vivo systems.