Phosphorylation of Cdc37 decreased its interaction with clients.
A, HCT116 cells transfected with FLAG-Cdc37(WT), FLAG-Cdc37(S127E), FLAG-Cdc37(T131E), or FLAG-Cdc37(S339E) were subjected to FLAG immunoprecipitation (IP). B and C, HCT116 cells were cotransfected with FLAG-Ulk1 plus GFP-Cdc37 (B) or GFP-Cdc37-S339A (C). 24 h after transfection cells were subjected to GFP immunoprecipitation. D, HCT116 cells transfected with FLAG-Ulk1 and myc-Hsp90 were subjected to myc immunoprecipitation. E, HCT116 cells transfected with FLAG-Ulk1 and myc-Hsp90 were subjected to immunoprecipitated with an antibody to Cdc37. F, a set of RNAi-resistant rescue forms of Cdc37 plasmids were transfected into stable Cdc37-RNAi HCT116 cells. 24 h after transfection cells were treated with phenformin and then subjected to FLAG immunoprecipitation.