Fig. 2: Design of binary-mixed DNA droplets.
From: Temporally controlled multistep division of DNA droplets for dynamic artificial cells
a Schematic of DNA droplet formation. Y-shaped branched DNA nanostructures self-assemble via binding of palindromic sticky ends, forming a DNA droplet. b Binary-mixed DNA droplet formation. Sticky ends of YA and YB are crosslinked by 6-branched DNA linker LAB. After the self-assembly of these DNA nanostructures, a binary-mixed DNA droplet (A·B-droplet) is formed. c CLSM images of A·B-droplets. Green: YA labeled with 6-carboxyfluorescein (6-FAM); Blue: YB labeled with Alexa Fluor® 405 (Alexa405). Co-localization of YA and YB was observed. Scale bars: 10 μm. Experiments were repeated three times independently with similar results. d, e Division of A·B-droplet via LAB cleavage. LAB is designed to be cleaved by a strand-displacement reaction with ssDNA division triggers (TAB1 and TAB2). f Description of the A·B-droplet division dynamics based on reaction landscapes. The ssDNA division triggers change the reaction landscape from a single-minimum shape: (i) A·B-droplet with ssDNA triggers but the A·B-droplet is not divided yet; (ii) A- and B-droplets are divided through the spinodal decomposition. ΔGClv and ΔGPS are Gibbs free energy changes for the linker cleavage reaction and the phase separation, respectively. g Time-lapse images of A·B-droplet division. Scale bars: 10 μm. Experiments were repeated three times independently with similar results.
