Fig. 4.

Neuronatin silencing potentiates mitochondrial biogenesis and a BAT-like phenotype in inguinal white adipocytes. Expression levels of thermogenic marker genes in control and NE/Rosi-stimulated cultures of inguinal white adipocytes were measured with and without neuronatin silencing. A: inguinal white adipocytes were analyzed for mitochondrial abundance by MitoTracker Green staining. Cells were examined with a fluorescence microscope, and representative images are shown. Fluorescence intensity was measured as described in methods. PGC-1α (B), Cox8b (C), and UCP1 (E, note logarithmic y-axes) mRNA levels are shown in control and NE/Rosi-treated inguinal white adipocytes with and without neuronatin siRNA pool. Expression levels in untreated adipocyte cultures were set in each experiment to 1.0, and levels in the other cultures were expressed relative to this value in each experiment. Values represent means ± SE of 5 independent experiments. D: protein levels of Cox4 in control and NE/Rosi-treated inguinal white adipocytes with and without neuronatin siRNA were analyzed by Western blotting, and the graph represents means ± SE of 4 independent experiments. Statistical analysis was performed as described in methods.