Fig. 2.

Sumoylated RhoB is translocated to lysosomes. a Sumoylation of RhoB is specific to ultraviolet (UV) or methyl methanesulphonate (MMS) treatment. One hour after treated with UV (80 Jm⁻²) or 2 h after treated with MMS (0.5 mM), camptothecin (CPT) (10 μM), or doxorubicin (DOX) (0.5 μM), HEK293T cells expressing HA-SUMO2 and His-RhoB were subjected to sumoylation assay to detect the SUMO2 conjugation of RhoB. b UV or MMS treatment enhances sumoylation of endogenous RhoB. HeLa cells with expression of His-SUMO2 were subjected to sumoylation assay 2 h after treated with UV (80 Jm⁻²) or 4 h after treated with MMS (0.5 mM). SUMO2 conjugation of RhoB was detected by immunoblotting with RhoB antibody. c Endogenous RhoB colocalizes with LAMP1 after UV or MMS but not CPT or DOX treatment. HeLa cells were subjected to immunofluorescence assay 2 h after treated with or without UV (80 Jm⁻²), MMS (0.5 mM), CPT (10 μM), or DOX (0.5 μM). Scale bar, 10 μm. d RhoB WT but not RhoB-4KR colocalizes with LAMP1 after UV or MMS treatment. U2OS cells expressing HA-RhoB (WT or 4KR) were subjected to immunofluorescence assay 4 h after UV (80 Jm⁻²) or MMS (0.5 mM) treatment to examine the localization of HA-RhoB and endogenous LAMP1. Scale bar, 10 μm