(A) Incubation of GST or GST-p9 with IE or ME, followed by IB of input and bound proteins with the indicated antibodies. (B) ME was first incubated with GST or GST-p9 at 4°C for 2 h, and then treated with CIP. IE, ME, and the two samples of differently treated ME were immunoprecipitated with IgG or 1A3, followed by IB with the indicated antibodies. (C) Left: experimental flowchart. Middle: IP of cell lysates with the indicated antibodies, followed by IB with αGFP. Right: IB of cell lysates with the indicated antibodies. (D-F) HEK293 cells were processed as diagrammed. IB of VLPs and cell lysates with the indicated antibodies. Relative levels of the VLP production were determined (n = 3 ± SD). See also Figure S4.