HSP90-pY197 is required for interaction with SYK. (A) MS spectrum showing downregulation of pY197 of HSP90 upon CD79a knockdown in DG75 cells. The inset shows the MS peaks for the light-labeled pY197-containing peptide. Here, signals from a coeluting peptide were removed for better visualization. Raw data were taken from Corso et al.⁵  (B) Coimmunoprecipitation of wild-type (wt) and mutant (Y197F) HA-tagged HSP90 proteins and SYK. CCL from DG75 (left) and Daudi (right) cells were subjected to immunoprecipitation using anti-HA antibodies (B) or anti-SYK antibodies (C) and blotted for HA, SYK, and AKT.