Fig. 4.

Ub chain specificity of 5 S. pombe membrane trafficking DUBs. (A) In vitro di-Ub cleavage reactions (see Experimental Procedures for details). Cleavage efficiencies were calculated as the ratio of cleaved/uncleaved x100. Preferred chains (bright orange) were cleaved most efficiently (i.e. 100% normalized cleavage efficiency), and the other colors are as indicated with lower cleavage efficiency (see Supplemental Fig. S4). These results are the average of two independent experiments. (B) In vivo detection of Ub chains using quantitative mass spectrometry (see Experimental Procedures and Supplemental Table 9 for details). Numbers indicate fold increases in detected chain types in the DUB delete (indicated) strains compared with WT S. pombe cells (ratios are average of three experiments).