Figure 4.

PML and ΔNp63, substrates of SENP, are not desumoylated by DeSI-1. (A) 293T cells were transfected with the indicated combinations of expression plasmids encoding PML, SUMO1, DeSI-1 and/or SENP1. Cell lysates were subjected to immunoprecipitation with the anti-Myc antibody, followed by immunoblot analysis with anti-HA or anti-Myc antibodies. To control for the expression of DeSI-1 and SENP1, WCE was analysed by immunoblot (IB) analysis using the anti-FLAG antibody. (B) The experiment was performed as described in A, except that SuPr1 was expressed instead of SENP1, and the sumoylation of ΔNp63, instead of PML, was analysed. DeSI-1, DeSumoylating Isopeptidase 1; HA, haemagglutinin; IP, immunoprecipitation; SENP1, sentrin-specific proteases 1; SUMO1, small ubiquitin-like modifier 1; WCE, whole-cell extract.