USP17 stabilizes HDAC2 by deubiquitination. A. HEK 293T cells were transfected with Flag-HDAC2, Myc-USP17, His-K48 only or K63 only-Ubiquitin plasmids, lysed for Ni-NTA pull down assay. B. HEK 293T cells were transfected with His-Ubiquitin, Flag-HDAC2, Myc-USP17 or its inactive mutant plasmids using PEI and then cultured for 48 h, lysed for Ni-NTA pull down assay. C. A549 cells were transfected with Myc-USP17 or its inactive mutant plasmids using Lipo and treated with CHX (20 μg/ml). Cells were harvested at indicated time-points and lysed for Western Blotting.