Figure 2
From: Programmable DNA Nanosystem for Molecular Interrogation
System characterization and demonstration using FRET and Transmission Electron Microscopy (TEM).
(a) A TEM field showing examples of the ground state of OPTIMuS. White arrows adjacent to some structures indicate single-stranded “clouds” of DNA corresponding to the unhybridized force domains. (b) FRET output of OPTIMuS as a function of combination of pre-added (during self-assembly) force domain components. FRET is a reliable indicator of ring/frameR distance and, therefore, a reporter of force-induced ring motion. A schematic of each configuration is shown for clarity. In case of G + ECS, pre-adding ECS affects the stable formation of the structure due to internal tension between Ch and EC, thereby destabilizing the formation of the frame (Supplementary Fig. 1). This is one type of internal tension that comprises the foundation of mechanical actuation in the nanosystem. (c) Corroborating TEM structures corresponding to key OPTIMuS configurations used in this study (Scale bar = 50 nm). Green and yellow arrows indicate structural “gaps” corresponding to ssDNA L and ssDNA Ch domains respectively.
