FIGURE 4:

Cytosol from CNIH KO HeLa cells displays higher COPII activity in vitro. (A) LiCor analysis of an in vitro budding reaction. WT HeLa cells were transiently transfected with plasmids encoding pro/HA-TGFα, and membranes were harvested for use in the in vitro budding reaction. Cytosol was harvested either from WT HeLa cells or CNIH KO HeLa cells and used in the in vitro budding reaction. Lanes 3–5 are triplicates of budding reactions done using cytosol prepared from WT HeLa cells. Lanes 6 and 7 are duplicates of budding reactions done using cytosol prepared from CNIH KO HeLa cells. (B, C) Quantification of budding efficiency of pro/HA-TGFα (B) and Sec22 (C). Quantifications are represented as mean ± SEM (***p < 0.001; **p < 0.01). (D) Immunoblot of cytosol prepared from WT or CNIH KO HeLa cells.