Figure 3.

UBR7 is not a conventional N-recognin

(A) HEK293T cell lines are transfected with Thermo Fisher Scientific pre-designed siRNAs for UBR7 (UBR7-1 targeting exon 4 of NM_175748.3, product ID S30283; UBR7-2 targeting exon 7, S30284; and UBR7-3 targeting exon 9, S30285).

(B) Model N-end rule substrate X-nsp4 processing mechanism involving dubiquitination enzyme.

(C) X-nsp4^FLAG(X = Met, Arg, Tyr) constructs are transfected after siRNA-mediated UBR7 silencing.

(D) Same as with (C). but with 10 uM of MG132 treatment for 6 h. Experiments were performed in duplicates with similar results, and representative blots are shown.