Figure 9.

GCC185 depletion alters the levels of CI-MPRs. (A) CI-MPR protein levels determined by immunoblot of equal amounts of control (mock transfected) or GCC185 siRNA-treated cells. Values are graphed as a function of the percentage of GCC185 depleted in four separate experiments; the data are presented in relation to matched control samples (100 ± 27%; n = 9). The inset shows an example blot from one GCC185 depletion experiment with ∼60% depletion. (B) Levels of Golgin-97, CI-MPR and GCC185 in Golgin-97 siRNA-treated cells relative to control (mock-transfected) cells, determined by immunoblot. The small gels above each bar show the control and depleted levels for each distinct protein. Equal amounts of extract protein were analyzed in each case. (C) CI-MPR is unstable in GCC185-depleted cells. HeLa cells treated with GCC185 siRNA were labeled with [³⁵S]methionine/cysteine and chased for the indicated times along with control cells. Equal amounts of cells were harvested (as determined by protein assay), and the CI-MPR was immunoprecipitated and subjected to SDS-PAGE and autoradiography. (D) Quantitation of the experiment shown in C, plotted on a semilog plot.