UVB induces USP11 recruitment to the chromatin ( A, B ) Immunoblot analysis of USP11 and GAPDH in HaCaT cells (A), and normal human epidermal keratinocyte (NHEK) cells (B) with or without MG132 treatment (10 µM) 1 h prior to UVB (20 mJ/cm 2 ). ( C ) Immunoblot analysis of USP11, GAPDH, and Lamin B using nuclear [N] and cytoplasmic [C] fractions from HaCaT cells with or without UVB (20 mJ/cm 2 , 30 min). ( D ) Immunoblot analysis of USP11, Histone 3, and XPC using chromatin bound protein fractions from HaCaT cells over a time course post-UVB (20 mJ/cm 2 ).