Journal: The Journal of Clinical Investigation

Article Title: SIRT2-mediated deacetylation activates USP22 catalytic function for PD-L1 protein stabilization and tumor immune escape

doi: 10.1172/JCI198270

Figure Lengend Snippet: ( A ) USP22 ubiquitination was detected by IP using anti-Myc antibodies and immunoblotting with anti-HA antibodies. ( B ) Ubiquitination assay of USP22 in WT and SIRT2-KO T24 cells. ( C and D ) Stability assay of Myc-USP22 in HEK293T cells cotransfected with or without Flag-SIRT2 treated with CHX. ( E and F ) Stability assay of endogenous USP22 in WT and SIRT2-KO T24 cells following CHX treatment. ( G – I ) WT and SIRT2-KO cells were treated with NH 4 Cl ( G ) or MG132 ( H and I ). USP22 and SIRT2 expression and PD-L1 ubiquitination were determined. Data are shown as mean ± SD. Statistical significance was determined using unpaired 2-tailed Student’s t test for D and 1-way ANOVA for F . * P < 0.05; ** P < 0.01; *** P < 0.001.

Article Snippet: For protein degradation pathway analysis, SIRT2-KO T24 cells were treated with the proteasome inhibitor MG132 (MedChemExpress, HY-13259) or the lysosomal inhibitor NH 4 Cl (MedChemExpress, HY-Y1269).

Techniques: Ubiquitin Proteomics, Western Blot, Stability Assay, Expressing