Analysis of GpLuc accumulation in proliferating and differentiating 1∶1 co-cultures of myoblasts^GS.GLuc and either myoblasts-FLPe^NLS+ or myoblasts-FLPe^NLS⁻.

<p>(<b>A</b>): Luminometric analysis of culture medium of co-cultures of 50% myoblasts^GS.GLuc and 50% myoblasts-FLPe^NLS+ (+) or 50% myoblasts-FLPe^NLS− (−). At 72 h after cell seeding, the culture fluid was replaced by fresh culture medium with (growth conditions, no differentiation) or without (differentiation conditions) serum, which was left on the cells for the indicated periods of time. Bars represent mean ± standard error of the mean (n = 3). (<b>B</b>): Fold change in luciferase activity calculated on the basis of the data presented in (A). For each sampling time the average light production under growth conditions was the denominator and the mean of the RLUs produced under differentiation conditions was the numerator. RLUs, relative light units; NLS, nuclear localization signal.