Fig. 3.

Activation of protein degradation in STZ mice. A and B: activation of protein degradation pathways was determined by real-time PCR for proteasome pathway (E3 ubiquitin ligase; A) and autophagy (beclin; B). Immunoblotting revealed insulin deprivation decreased accumulation of the autophagy receptor protein p62 in quadriceps lysates (C) and isolated mitochondria fractions (D), indicating activation of autophagy. Autophagy negative (HeLa cells untreated) and positive controls (HeLa cells + chloroquine) were included in lanes 1 and 2. Loading controls were vinculin (Vinc) for muscle lysates and complexes III and V for isolated mitochondria. Representative images are from a single blot, with vertical bars representing discontinuous lanes. Data are means ± SD with n = 5–7 mice/group. *P < 0.05 vs. control. AU, arbitrary units.