Fig 1: CD44 and ACVR2B can physically interact in melanoma cells. B16-F10 and Ret cells were pre-incubated with HA (50 µg/ml) for 48 hours, and then stimulated with or without BMP7 (10 ng/ml) for another 6 hours. Cell lysates were then analyzed for CD44 and ACVR2B protein expression by co-immunoprecipitation assays. In each case, the samples in the two left panels were immunoprecipitated with CD44 antibodies, and the samples in the right panels were immunoprecipitated with ACVR2B antibodies. The Western blots were probed with either CD44 or ACVR2B antibodies as indicated. Isotype control antibodies were used for negative control immunoprecipitations. Densitometric quantification is shown below the Western blots, representing the signal relative to the input lanes.