Fig. 7: MVP stabilizes Parkin in endothelial cells.

A, B Co-immunoprecipitation (Co-IP) of GFP-tagged Parkin (GFP-Parkin) and Flag-tagged MVP (Flag-MVP). HEK293T cells were co-transfected by GFP-Parkin and Flag-MVP. Cell lysates were immunoprecipitated by anti-Flag antibody and were immunoblotted by anti-GFP antibody (A), or immunoprecipitated by anti-GFP antibody and immunoblotted by anti-Flag antibody (B). C, D Co-localization staining of MVP (red) with Parkin (purple) in CD31⁺ ECs (green) of murine (C) and human (D) atherosclerotic plaques. Scale bars = 20 μm. E Proximity ligation assay (PLA) indicating the interaction between MVP and Parkin (red dots) in murine atherosclerotic plaques. Scale bars = 20 μm. F Co-IP of GFP-Parkin and Flag-MVP in the HEK293T cells treated by CCCP (10 μM) for 30 min. G MVP knockdown on Parkin expression in HUVECs (n = 4, independent biological replicates). H MVP overexpression on Parkin expression in the HUVECs treated by cycloheximide (CHX) (n = 3, independent biological replicates). I MVP knockdown on Parkin expression in the HUVECs treated by 26S proteasome inhibitor MG132 (20 μM) for 6 h (n = 3, independent biological replicates). J Co-IP of GFP-Parkin, HA-Ub, and Flag-MVP in the HEK293T cells treated by MG132 (20 μM) for 6 h. K Co-IP of GFP-Parkin, HA-Ub-K48O, and Flag-MVP in the HEK293T cells treated by MG132 (20 μM) for 6 h. L Representative IF staining of Parkin (green), COXIV (red), and DAPI (blue) in the MVP knockdown HUVECs treated by CCCP for 2 h. Fifteen cells per group (n = 15). Scale bar = 20 μm. M Co-IP of GFP-Parkin, Myc-NEDD4L, and Flag-MVP in HEK293T cells. N Co-IP of GFP-Parkin, Myc-NEDD4L, HA-Ub-K48O, and Flag-MVP in the HEK293T cells treated by MG132 (20 μM) for 6 h. O Effects of MVP and NEDD4L knockdown on the Parkin expression in HUVECs (n = 3, independent biological replicates). Data are presented as mean ± SEM. Statistical significances are assessed by two-tailed Student’s t-test (G), two-way ANOVA with Bonferroni’s multiple comparisons test (H), Mann-Whitney test (L), or one-way ANOVA followed by Tukey post hoc test (I, O). Experiments were repeated independently with similar results three times in A-F, J, K, M, and N. ns, no significance. Source data are provided as a Source Data file.