This study investigates protein complexes associated with RacK1 under conditions of mTOR inhibition. Wild-type HeLa cells were treated with the mTOR inhibitor Torin1, followed by immunoprecipitation using a RacK1-specific antibody to enrich RacK1-associated protein complexes. The immunoprecipitates were analyzed by liquid chromatography–tandem mass spectrometry (LC–MS/MS) to identify proteins associated with RacK1 in Torin1-treated cells.