FIGURE 5.

Structure-guided engineering toward condensates with novel functions. (A, left) Structure of the guanidine riboswitch monomer and (middle) with broccoli aptamer insert (green). (Right) Predicted multimerization architecture for the broccoli insert-containing guanidine riboswitch shown out to a hexamer. Each copy of the transcript is a separate color. (B) Fluorescence intensity at 520 ± 15 nm of in vitro transcription reactions in the presence of 10 µM DFHBI dye and 10 mM KCl for both WT (gold) and the broccoli insert-containing (green) guanidine riboswitch. Note that graphs for Gdn WT (±KCl) are indistinguishable. (C) Microscopy images showing fluorescence from either CF-647 labeled RNA (∼15% labeled RNA) (top row) or from the broccoli aptamer (bottom row). All experiments contained 10 mM KCl to promote Broccoli fluorescence except panels 4 and 8.