Figure 1.

ClpP1P2 and proteasome inhibition assays. (A) ClpP1P2 inhibition assay principle. Under undisturbed conditions, ClpP1P2 recognizes and degrades SsrA-tagged (YALAA) RFP protein resulting in a low fluorescence level. In the presence of a ClpP1P2 inhibitor like Bortezomib, RFP is not degraded. Its accumulation results in an increase in fluorescence. (B) Proteasome inhibition assay principle. Under undisturbed conditions, the proteasome recognizes the Z-LLVY tag and cleaves it. The aminoluciferin is used as a substrate by the luciferase enzyme to generate luminescence. In the presence of a proteasome inhibitor like Bortezomib, the cleavage of Z-LLVY is prevented. The lack of luciferase substrate results in a reduced luminescence emission. RFU, relative fluorescence unit; RLU, relative luminescence unit.