Fig. 6: RNF144A-VRK2-G3BP1 axis participates in cisplatin-mediated SG formation.

A Representative image of SG formation in U2OS cells. The stress was induced by the treatment with cisplatin (50 μM, 2 h). SGs were stained with G3BP1 (green), and the nuclei of cells were stained with DAPI (blue). Scale bar = 50 µm. B Proportion of U2OS cells with SGs were quantified in U2OS cells treated with cisplatin (n = 10). Representative immunoblot (C) and the quantification of RNF144A (D), VRK2 (E), and G3BP1 phosphorylation (F) in stress-induced U2OS cells. The stress was induced with cisplatin (50 μM, 8 h). p53 was used as the marker for cisplatin-induced stress. The phosphorylation of G3BP1 is normalized to total G3BP1, and GAPDH was used as loading control (n = 3). G Representative image of SG formation in VRK2-excessive U2OS cells. U2OS cells were transfected with pNTAP-VRK2, and the stress was induced by the treatment with cisplatin (50 μM, 2 h). SGs were stained with G3BP1 (green), and the nuclei of cells were stained with DAPI (blue). Scale bar = 50 µm. The formation of SG in single cell is shown through up-scaled image (1 A and 1B, Scale bar = 25 µm). Proportion of U2OS cells with SGs (H) and average number of SGs per U2OS cells (I) were quantified in control or VRK2-excessive U2OS cells (n = 10). *p ≤ 0.05, **p ≤ 0.01, ***p ≤ 0.001, ****p ≤ 0.0001; ordinary one-way ANOVA with Tukey’s multiple comparison test was performed for (B); unpaired Student’s t test was performed for (D, E, F, H, I). The “n” represents the number of independent experiments. Error bars indicate SDs.