Fig. 4: Controlling gene expression in synthetic cells with an alternating magnetic field.
From: Magnetic activation of spherical nucleic acids enables the remote control of synthetic cells
a, Epifluorescence microscopy images of magnetically activated SNAs and in situ mNG expression in synthetic cells with and without exposure to an AMF. Synthetic cells (visualized through the encapsulated TXR) that were not exposed to an AMF expressed minimal mNG, and their GFP channel fluorescence intensity was comparable to synthetic cells that contained PURExpress and the inactive DNA template only. Synthetic cells exposed to an AMF expressed mNG, as demonstrated by the increase in the green channel fluorescence, and were consistent with synthetic cells containing the full mNG template (dsDNA T7 promoter region present). Images are representative of n = 3 biological replicates. Scale bar, 20 μm. T, temperature. b, Quantification of mNG expression in the individual GUVs using a circle-detection-based image analysis script. Mean fluorescence intensity (inactive template), 0.00 grey units; mean fluorescence intensity (SNA, no AMF), 3.03 grey units; mean fluorescence intensity (full template), 17.47 grey units; and mean fluorescence intensity (SNA, AMF), 23.22 grey units. Datasets are representative of n = 3 biological replicates. The boxplot, notch and asterisk represent the interquartile range, median and mean fluorescence intensity, respectively. c, Epifluorescence microscopy images of magnetically activated SNAs and in situ mNG expression in synthetic cells within an opaque blocking material (black tube, see image). Synthetic cells that were not exposed to an AMF expressed minimal mNG, whereas synthetic cells exposed to an AMF expressed mNG, unperturbed by the blocking layer. Images are representative of n = 2 biological replicates. Scale bar, 20 μm.
