FIGURE 1.

Influence of SUMOylation on protein phosphorylation. A, inhibition of SUMO modification by ginkgolic acid. HEK293T cells were treated with 100 μm ginkgolic acid or DMSO as a control for 6 h before harvest, then lysed and probed with anti-SUMO1 and SUMO2/3 antibody. Actin was used as a loading control. IB, immunoblotting. B, the same samples from A and pervanadate-treated samples were blotted with pan-anti-phospho-tyrosine antibody. Actin was used as a loading control. C, HEK293T cells were transfected with pcDNA3.0 control, HA-SUMO1, or HA-SUMO2 plasmids and were starved for 18 h after 24 h of transfection. Cells were then harvested, lysed, and blotted with anti-SUMO1, SUMO2/3, and HA antibodies. D, the same samples from C were blotted with pan-anti-phospho-tyrosine antibody. Actin was used as a loading control. E, SUMO1 or SUMO2/3 shRNA plasmids, as well as LacZ plasmid control, were transfected into HEK293T cells for 48 h. Cells were harvested, lysed, and blotted with anti-SUMO1 and SUMO2 antibody. Actin was used as a loading control. F, the same samples from A and E were blotted with anti-FAK and anti-pTyr-FAK antibody. Actin was used as a loading control. Pv, pervanadate.