PGC-1α modulates mitochondrial biology and insulin signaling.
A shows murine PGC-1α promoter activation in response to
pioglitazone (cont, control; Pio, pioglitazone). B,
infection of PGC-1α up-regulates PGC-1α and COX I protein levels.
MOI, multiplicity of infection. C, augmentation of relative
rate of oxygen consumption in cells with increasing levels of PGC-1α and
the relative O2 consumption comparing GFP to PGC-1α vector at
a multiplicity of infection of 100. D shows the restoration of
insulin-mediated signaling (% GFP/cont without insulin) by PGC-1α
overexpression (pTyr, phosphotyrosine; cont, control).
E, induction of oxygen consumption by PGC1α overexpression in,
insulin resistance myotubes. F, effect of PGC-1α silencing on
transcript levels and on oxygen consumption (% si cont); G,
the diminution of Akt threonine phosphorylation by insulin after partial
silencing of PGC-1α.