Manipulation of biological activities with MNTs from the single-cell to the single-molecule level. (a) Single-cell signaling control. (i) Mechanical activation of Notch receptor signaling. (ii) The mCherry fluorescence increases under sequential magnetic field application to 3 target cells. (iii) Magnetic field simulation for single-cell-level apoptosis induction by m-TAT. (iv) Sequential activation of apoptosis signaling. The green fluorescence signal (FITC-annexin V) indicates the induction of apoptosis. (b) Interrogation of subcellular VE-cadherin-mediated adherens junction formation: (top) MPN-induced VE-cadherin clustering; (bottom) F-actin assembly recruitment. (c) Single-molecule activation of mechanoreceptors in live cells. Under the application of a strong pulling force (9 pN, top), the immediate detachment of the MPN is detected under dark-field microscopy (bottom). Reproduced from ref 13, Copyright 2016, with permission from Elsevier; Reproduced with permission from ref 15, Copyright 2016 American Chemical Society; Reproduced with permission from ref 20, copyright 2017 Nature Publishing Group.