Figure 6.

Amino Acid Imbalance Mediates the Lethality Resulting from Proteasome Inhibition in Drosophila

(A) Changes in the content of free amino acids in Drosophila treated with or without 50 μM Bortezomib for 3 days. Asx, asparagine/aspartate; Glx, glutamine/glutamate. Data are means ± SEM (30 flies per conditions, from six independent experiments). ^∗∗p ≤ 0.005; ^∗∗∗p ≤ 0.001.

(B) Survival of Drosophila either untreated or treated with 50 μM Bortezomib, with or without additional amino acids (AA), at the concentration used in Grandison et al. (2009). Data are means ± SEM (400 flies per condition, from four independent experiments). ^∗∗p ≤ 0.005; ^∗∗∗p ≤ 0.001.

(C) Polyubiquitin (Ubⁿ) immunoblots from lysates of flies treated with 50 μM Bortezomib and additional amino acids, where indicated. Ponceau staining of the membrane. Representative results of at least three independent experiments are shown.