KBTBD4 and medulloblastoma: As an initial strategy to identify substrates of KBTBD4, we immunoprecipitated KBTBD4WT, KBTBD4R313PRR and KBTBD4P311PP (the most recurrent mutations in group 3 and 4 medulloblastomas, respectively) (Fig. 1A) [5] from HEK293T cells and performed tryptic digestion and Liquid Chromatography/Tandem Mass Spectrometry (LC-MS/MS) to analyse their interacting partners.