Figure 2. Glucagon induces mitochondrially encoded genes and proteins.

(A) Neither insulin/dexamethasone (Insulin+Dex) nor their withdrawal (Vehicle) had an effect on mitochondrially encoded gene expression; however, glucagon induced mitochondrially encoded gene expression. (B) Effect of glucagon on several nuclear encoded ETC subunits. (C) Effect of glucagon on fasting-responsive genes and regulators of mitochondrial content and function. (D) [³⁵S]-methionine labeling of cytoplasmic proteins (left 2 lanes) and mitochondrially encoded translation products, which were evident after inhibition of cytoplasmic translation with cycloheximide (CHX) (middle 6 lanes). Consistent with mitochondrial translation products, chloramphenicol (CAP) blocked their translation (right 2 lanes). GCG, glucagon. (E) Coomassie brilliant blue staining of the [³⁵S]-labeled gel, showing equal protein loading. (F) Quantification of mitochondrially encoded [³⁵S]-labeled proteins by scintillation courting (n = 3). Data are mean ± SEM. **P < 0.01, ***P < 0.001, 2-way ANOVA, with (B and C) or without (A) Bonferroni post-test, or 2-tailed unpaired Student’s t test (F).