Figure 5.

MALT1 protease activity-supported mitochondrial bioenergetics is dependent on glutaminolysis. (A) ¹³C isotopomer analysis of uniformly labeled glucose (U¹³C₆-glucose) in U2932 cells treated with z-VRPR-fmk or not for 12 h. The isotopolog distributions were determined by GC-MS. The incorporation of ¹³C atoms from ¹³C₆-Glc into pyruvate, lactate, citrate, a-ketoglutarate (a-KG), succinate, fumarate, and malate are denoted as m+n, where n is the number of ¹³C atoms. (B) Western blot to detect GLS1 in ABC-DLBCL cells pretreated with vehicle, VRPR or MI-2 for 12 h. β-Actin blotting served as the loading control. One representative experiment of three is depicted. (C) Relative glutamate levels in ABC-DLBCL cells from (B). (D) Profiles of mitochondrial respiration in ABC-DLBCL cells pretreated with vehicle, VRPR, BPTES, or VRPR+BPTES for 12 h. OCR was assayed after consecutive injections of Oligo (1 μM), FCCP (0.5 μM), rotenone (1 μM), and antimycin (1 μM). (E) OCR of the graphs in (D) were calculated. All the graphs represent as the mean ± SD of three independent experiments. *p < 0.05; **p < 0.01.