BRISC and SHMT2 Share the Same Cellular Compartments In Vivo and Vary in Concentration across Cell Lines and Tissues
(A) Endogenous SHMT2 and ABRO1 colocalize to nucleus and cytosol in quantitative immunofluorescence experiments. Error bars represent mean ± SD. SHMT2: n = 13 replicates. ABRO1: n = 9 replicates. Every image contained 2–10 individual cells.
(B) BRISC DUB activity at substrate and SHMT2 concentrations encountered inside healthy and diseased human cells ranges from fully active to completely inhibited. BRISC DUB activity corresponding to the concentrations of SHMT2α and ABRO1 in HeLa cells is shown in red.
(C) Concentrations of ABRO1 and endogenous SHMT2 in healthy human tissues (gray squares) and cancer cell lines (black circles) suggest that BRISC is attenuated by no more than 50% in healthy human cells but mostly inhibited in cancer cell lines. Concentrations of SHMT2 and ABRO1 corresponding to HeLa cells are shown in red.