RGG domain mediates FUS mobility and its functional role in HSCs. (A) This schematic diagram shows the components of each FUS variants, including FUS^ΔLC, FUS^ΔRGG1, FUS^ΔRGG2, FUS^ΔRGG3, FUS^ΔRGG123, and FUS^ΔNLS. (B-C) Freshly isolated LSK cells from 2-month-old young WT mice were infected by lentivirus carrying FUS and FUS variants, and 3 days later, GFP⁺ cells were purified and treated with 0.5 mM ARS. (B) These representative images show the FUS condensates in the cytoplasm of indicated groups upon 0.5 mM ARS treatment for 1 hour. Scale bar represents 5 μm. (C) These representative images show the FUS condensates in the nucleoplasm of the indicated groups upon 0.5 mM ARS treatment for 4 hours. Scale bar represents 5 μm. (D) This histogram shows the quantification of the percentage of cells with FUS condensates in panel B. N = 89-313 cells per group. Data are shown as mean ± SEM. (E) This histogram shows the quantification of the FUS condensate numbers per cell in panel C. N = 74-256 cells per group. Data are shown as mean ± SEM. (F) These representative images exhibit the droplets formed by FUS variants at the protein concentration of 200 nM. The scale bar indicates 20 μm. (G) These line plots depict the percentage of donor-derived cells (overall, B cell, T cell, myeloid cell) in the peripheral blood of the recipients at the indicated time points. Freshly isolated 10⁵ LSK cells from 2-month-old young WT mice were infected by lentivirus carrying FUS and FUS variants. Three days later, 2000 GFP⁺Sca-1⁺CD48^– cells were purified and transplanted into lethally irradiated recipients (CD45.2) together with 3.5 × 10⁵ competitor cells (CD45.1). Chimera in peripheral blood was evaluated every 4 weeks until the 16th week. N = 4-7 recipients per group; data are shown as mean ± SEM.