FIG. 8.

Expression of AMF1(1–103) interferes with wild-type AMF1 function in vivo. (A) AMF1(1–103) inhibits p53 transcriptional activation in Saos-2 cells. A total of 500 ng of p53-dependent luciferase reporter PG13 was cotransfected into Saos-2 cells with or without vectors expressing p53, AMF1(1–327) (wild type), and AMF1(1–103) as indicated. A total of 100 ng of pC53SN plasmid was used. Total DNA for each transfection was made up to 6.6 μg by using vector plasmid pCG. Luciferase activities were measured at 32 h after transfection and are presented as the increase in activation over reporter alone. Each sample was analyzed in triplicate, and standard deviations are shown (error bars). (B) In vitro binding of AMF1(1–103) to HA-AMF1. Both proteins were prepared by in vitro translation. Experimental procedures were the same as in Fig. 5B. Each input (10%) is shown in the first two lanes. Lanes 3 and 4 demonstrate that AMF1(1–103) can be coimmunoprecipitated by HA-AMF1 but not the anti-HA MAb.