Effect of Brefeldin A Treatment on the Resident Golgi Protein, MG160
TheGolgi apparatus (GA) plays a crucial role in the post-translational processing and sorting of many cellular proteins. A small number of Golgi-specific proteins have been identified, including MG160 (Gonatas et al., 1989), an integral membrane sialoglycoprotein concentrated in the medial cisternae. Analysis of the biochemical properties of theseGolgi-specific proteins should provide insight into the molecular mechanisms which underlie GA function. Here we examine the effects of BFA treatment on the lifecycle of MG160 in order to determine if it undergoes unique carbohydrate processing or targeting within the GA. Our data indicate that BFA promotes the accumulation of a 150 Kd precursor to MG160 which is Endo-H resistant, but not sialylated. These results raise interesting questions about the transit of MG160 through the GA.
KeywordsPC12 Cell Sialic Acid Trans Golgi Network Golgi Protein Final Shift
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