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In natural microenvironment, various proteins containing adhesive ligands in fibrous and non‐fibrous structures dynamically couple and decouple to regulate stem cell fate. Herein, materials presenting movably couplable ligands are developed by grafting liganded gold nanoparticles (AuNPs) to a substrate followed by flexibly grafting liganded movable linear nanomaterials (MLNs) to the substrate via a long bendable linker, thereby creating a space between the MLNs and the AuNPs in the decoupled state. Magnetic control of the MLNs decreases this space via the bending of the linker to couple the MLNs to the AuNPs. Remote control of ligand coupling stimulates integrin recruitment to the coupled ligands, thereby non‐toxically facilitating the focal adhesion, mechanosensing, and potential differentiation of stem cells, which is suppressed by ligand decoupling. Versatile tuning of size, aspect ratio, distributions, and ligands of the MLNs can help to decipher dynamic ligand‐coupling‐dependent stem cell fate to advance regenerative therapies. [ABSTRACT FROM AUTHOR]

Cellular adhesion is regulated by the binding of 10 nm sized integrin to Arg‐Gly‐Asp (RGD) ligands present in extracellular matrix proteins. In this study, seed‐mediated growth of gold nanoparticles (AuNPs) on the surface of iron oxide (Fe3O4) nanotemplates is employed to tune the diameter and interdistance of RGD‐bearing AuNPs at the receptor‐level. The Fe3O4 nanotemplates decorated with RGD‐bearing AuNPs arranged in various RGD diameters and interdistances at the receptor‐levels are flexibly fastened to a substrate. Similar to fully connected RGDs, subreceptor‐level‐gapped (quasiconnected) RGDs activate integrin binding with the adjacent RGDs, which stimulates focal adhesion, mechanosensing, and differentiation of stem cells. This stimulation of stem cells is hindered when the RGD interdistance increases above the receptor‐level gap. However, this stimulation is partially effective when the RGD diameter also increases far above the receptor‐level gap. Strikingly, magnetically attracted fastening of the RGDs toward the substrate via polymer linker tightening fully stimulates adhesion and differentiation of stem cells in a reversible manner, both in vitro and in vivo. Various RGD diameter and interdistance on Fe3O4 nanotemplates can further elucidate the dynamic receptor‐level RGD proximity‐regulated stem cell differentiation that govern tissue repair. [ABSTRACT FROM AUTHOR]