NEDD4-1/V5 and ABCG1-Myc co-IP.
A, left: CHO-K1 cells stably overexpressing ABCG1 were transfected with plasmid DNA encoding either pcDNA3.1 as control or NEDD4-1/V5 as described under “Experimental Procedures.” Immunoblots show expression of NEDD4-1 (top; native (N) and overexpressed (O) NEDD4-1 protein), ABCG1-Myc, and tubulin, respectively. Right: IP of ABCG1-Myc-overexpressing cells, transfected with NEDD4-1/V5. ABCG1-Myc band is only detected when cell lysate was IPed with anti-Myc (Myc) antibodies and absent with anti-flag control antibody (Ctrl). Results are representative of two independent experiments. B, CHO-K1 cells overexpressing ABCG1 were transiently transfected with HUWE1/V5 or NEDD4-1/V5 plasmids as described under “Experimental Procedures.” Cells were harvested and subjected to SDS-PAGE and Western blotting, and membranes probed with V5 antibodies, detecting only the overexpressed proteins.