FIGURE 10.

Effect of CHP3 expression on half-life of NHE1 upon arrest of cellular protein synthesis. A, AP-1 cells stably expressing either NHE1_HA alone or coexpressing both NHE1_HA and CHP3_myc were grown to subconfluence and then subjected to treatment with cycloheximide (100 μg/ml) to block de novo protein synthesis. At the indicated time points, cell lysates were prepared and fractionated by SDS-PAGE, followed by immunoblotting to visualize fully glycosylated (fg) and core-glycosylated (cg) NHE1_HA and CHP3_myc. B, fully glycosylated bands of NHE1_HA presented in A were quantified by densitometry and displayed as a percentage of their maximal levels as a function of time following cycloheximide treatment. Values represent the mean ± S.E. of four experiments.