The partition coefficients were 3.0 ± 0.9, 6.4 ± 1.8, and 5.9 ± 1.7 for YK11, YK13, and YK15, respectively (Fig. ). The structures overlapped with neither G3BP1 (a stress granule marker ) nor vimentin (aggresomal marker ), suggesting that the YK-based granules were independent of these natural bodies (Supplementary Fig. ). We also confirmed that YK13 fusion had negligible effects on sfGFP fluorescence intensity (Supplementary Fig. ) and cell viability (Supplementary Fig. ). Moreover, to obtain evidence of the self-association, we measured the fluorescence anisotropy (r) because Homo-FRET among proximal fluorescent proteins in complexes decreases the r . The results revealed that the r values of NES-YK-sfGFPs gradually decreased with a greater YK length (Fig. ).