Fig. 1

RNA LLPS induced by CPs. a Representative images of RNA droplets in 4T1 cells stained by SYTO RNAselect Green after treatment with different CPs. The CPs were labeled by Cy5. Scale bar, 5 μm. b Representative images of the FRAP experiment with Cy5-tagged CPs and SYTO RNAselect Green-stained RNA in 4T1 cells. Scale bar, 5 μm. c Quantification of the FRAP data (means ± SEMs, n = 3 experiments) of RNA droplets in 4T1 cells. d Phase diagrams of the CPs with concentrations ranging from 2.5 to 40 μg/ml in PBS (pH 7.0) and mRNA from 4T1 cells (ranging from 2.5 to 40 μg/ml). RNA was incubated with CPs in phase separation buffer at 37 °C for 30 min. Light dots, no phase separation; chromatic dots, phase separation. Phase separation was quantified by turbidity measurements at OD₆₀₀. e Representative images of the FRAP experiment with Cy5-tagged CPs and SYTO RNAselect Green-tagged RNA in PBS solution. Scale bar, 5 μm. f Quantification analysis of the FRAP data (means ± SEMs, n = 3 experiments) in (e). g Kinetic analysis of the turbidity at OD₆₀₀ in 4T1 cell cytoplasm with RNase or protease treatment before mixing with different CP solutions. 4T1 cell cytoplasm extract was treated with RNase A (20 μg/ml) at 37 °C and proteinase K (50 μg/ml) at 37 °C for 30 min