Fig. 6: USP47 is a candidate deubiquitinase for IK.

a HeLa cells were transfected for 48 h with individual siRNAs from a pool of 76 siRNA targeting deubiquitinases (DUBs). Next, the level of endogenous IK was measured by western blotting and protein bands were quantified using the Image J software. b Cells were transfected with 11 DUB siRNAs involved in DNA Damage Response (DDR), and the level of IK was examined. c Cells were transfected with three different siUSP47s for 48 h, and the levels of USP47 were examined. d Cells were transfected with siUSP47#1 for 48 h, and the levels of IK, SMU1, and USP47 were examined. e Cells were transfected with siUSP47#1 for 48 h, and the levels of IK mRNA were determined. The relative ratios of mRNA were normalized to those of β-actin and graphed. *p < 0.05. f Cells transfected with siUSP47 #1 for 24 h were transfected with Flag-USP47 for an additional 24 h, and the levels of IK and SMU1 were determined. g, h HEK-293T cells transfected with HA-IK or/and Flag-USP47 were immunoprecipitated with an anti-HA or anti-Flag antibody, and the levels of HA and FLAG were examined. i HeLa cells were immunoprecipitated with anti-USP47, and the levels of IK and USP47 were examined.