Related Experiment Videos
Cell type specific localization of sphingomyelin biosynthesis
F Sadeghlar1, K Sandhoff, G van Echten-Deckert
1Kekulé-Institut für Organische Chemie und Biochemie der Universität Bonn, Gerhard-Domagk-Strasse 1, 53121, Bonn, Germany.
FEBS Letters
|August 3, 2000
Summary
Brefeldin A (BFA) differentially affects sphingomyelin synthesis in neuronal cells versus fibroblasts. This suggests distinct cellular localization for sphingomyelin biosynthesis pathways, impacting complex ganglioside formation.
Area of Science:
- Cell Biology
- Biochemistry
- Neuroscience
Background:
- Sphingomyelin is a key component of cell membranes.
- Brefeldin A (BFA) is a drug that disrupts Golgi apparatus function.
- The cellular localization of sphingomyelin biosynthesis is not fully understood.
Purpose of the Study:
- To investigate the effect of BFA on sphingomyelin synthesis in different cell types.
- To determine the cellular localization of sphingomyelin biosynthesis.
- To compare sphingomyelin synthesis with glycosphingolipid formation.
Main Methods:
- Studied incorporation of [(14)C]serine and [(3)H]sphingosine into sphingomyelin.
- Used three cell types: fibroblasts, cerebellar neurons, and neuroblastoma cells.
- Administered BFA (1 microgram/ml) for 24 hours.
Main Results:
- BFA increased sphingomyelin synthesis in fibroblasts (1.5-3 fold).
- BFA decreased sphingomyelin synthesis in neuronal cells (4-5 fold).
- BFA similarly affected glycosphingolipid synthesis in all cell types, decreasing complex gangliosides while increasing precursors.
Conclusions:
- Sphingomyelin synthesis in neuronal cells is localized distal to the BFA block, likely in the trans-Golgi network.
- Sphingomyelin synthesis in fibroblasts is localized prior to the BFA block, within the Golgi apparatus.
- These findings highlight cell-type-specific differences in sphingomyelin and complex ganglioside biosynthesis localization.