Fig. 7.

(A) Bar graph of absolute protein quantitation in pmol/cell pellet for all three proteins quantified in 48-hour, 50 µg samples across the six passages used for experiments. (B) Normalization factors were calculated for actin and GAPDH and applied to spike quantitation. The amount of actin quantified in each passage was averaged and that average was used to calculate the normalization factor. The amount of actin quantified in each passage was then divided by the average to provide the normalization factor for that passage. Each passage had its own normalization factor. That amount of spike quantified in that passage was divided by the normalization factor of that passage. The same process was done for GAPDH to account for varying number of cells per well. Both housekeeping proteins provided equivalent correction indicating that either protein could be used as a housekeeping protein to quantify protein expression from BHK cells.