Figure 5.

Effects of PKA modulators on vesicle release from the TGN. (A) The standard assay described in Fig. 4 was supplemented or not (control) with either 8 units C-PKA, 20 μM PKI, 2 μg anti-C-PKA antibody or 2 μg preimmune rabbit IgG. (B) Incubation was performed in the presence of 8 units C-PKA but in the absence of either ATP (+apyrase) or cytosol (−cytosol) or in complete medium (control). VSV-G was immunoprecipitated from released, lysed vesicles, and where indicated (neu) subjected to neuraminidase digestion prior to SDS/PAGE analysis. (C) Effect of adding different amounts of both native (○) and heat-inactivated (90°C, 30 min) (•) C-PKA subunits on vesicle release. (D) Effect of adding different amounts of either PKI (○) or H89 (•) on vesicle release. Data are the average of three independent experiments.