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This content will become publicly available on August 23, 2026

Title: Engineering filamentous myosins for optical control of contractility
Abstract Understanding the behaviors of contractile actomyosin systems requires precise spatiotemporal control of filamentous myosin activity. Here, we develop a tool for optical control of contractility by extending the MyLOV family of gearshifting motors to create engineered filamentous myosins that change velocity in response to blue light. We characterize these minifilaments usingin vitrosingle-molecule tracking assays, contractility assays in reconstituted actin networks, and imaging of contractile phenotypes inDrosophilaS2 cells. The minifilaments change speed and/or direction when illuminated, display speeds that fall within and beyond the relevant physiological range, and display high processivities. Additionally, minifilament-driven contraction rates increase in blue light bothin vitroand in S2 cells. Finally, we develop an alternative design for minifilaments that only interact processively with actin in blue light. Engineered minifilaments can be used to dissect behaviors such as self-organization and mechanotransduction in contractile systems bothin vitroand in cells and tissues.  more » « less
Award ID(s):
2215605
PAR ID:
10644810
Author(s) / Creator(s):
; ;
Publisher / Repository:
bioRxiv
Date Published:
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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