Fig. 5. p66Shc association with SHP2 and Ser36 phosphorylation correlate with the focus-formation phenotype. (A,B) SHP2 (A) or Shc (B) were immunoprecipitated (IP) from lysates of HDFs expressing no (control) or the indicated viral oncoprotein. IPs were subjected to immunoblotting for Shc (A,B), SHP2 (A) or Ser36 phosphorylated (PS36)-p66Shc (B), as indicated. For the graphs shown below representative blots, the relative band intensities for the p66Shc blot in A and the phospho-Ser36 p66Shc blot in B were quantitated using the Image J program and normalized for total SHP2 and p66Shc amounts, respectively. These normalized values are expressed as a percentage relative to the level of p66Shc-SHP2 co-immunoprecipitation (A) or p66Shc Ser36 phosphorylation (B) observed in the wild-type E5-expressing HDFs. The mean values from two (A) or three (B) different experiments with the standard error are shown.