Optogenetic control of mechanotransduction based on light-induced homodimerization of talin

Integrin-based adhesion complexes serve as primary sites for actomyosin force transmission to the extracellular matrix, providing traction that drives cell mechanical responses including adhesion, migration, and mechano-signaling. Talin is the principal force-transmission protein that orchestrates molecular events underlying adhesion mechanosensing. Although talin has been an effective target for chemogenetic and optogenetic manipulation of integrin-based adhesions, existing approaches relied on dual-construct heterodimerization, creating challenges in maintaining consistent stoichiometric balance of each component and multiplexing with additional genetically-encoded probes. To overcome these limitations, we develop a single-construct optogenetic talin utilizing pdDronpa1.2 for light-inducible C-terminal homodimerization. We demonstrate its application by dissecting overlapping roles of dimerization and actin binding mediated by the native C-terminal region of talin, showing that artificial light-induced homodimerization is sufficient to promote talin recruitment to adhesion sites, adhesion formation, actin retrograde flow engagement, and downstream mechano-signaling, thereby underscoring the critical importance of talin dimer. Multiplexing of our single-construct optodimerizable talin with quantitative actin dynamics imaging or super-resolution single-molecule tracking are also showcased, establishing its versatility in spatiotemporally precise manipulation of mechanobiological processes.