Abstract
The effect of BFA on the metabolic processing and intracellular traffic of gangliosides was studied in cerebellar granule cells, fed in culture for different periods with radiolabeled ganglioside GM1. The following results were obtained: (a) degradation of taken-up GM1 was markedly inhibited by BFA; this effect was rapid, reversible, and affected by reduced temperature, ATP depletion, and microtubule disruption: (b) direct glycosylation of internalized GM1 to GD1a was completely blocked by BFA; (c) the portion of GM1 that escaped BFA inhibition was degraded with formation of sphingosine, that was recycled for the biosynthesis of less glycosylated glycolipids (glucosyl-ceramide, GM3 and GD3); (d) in BFA-treated cells highly glycosylated gangliosides were undetectable, and the formation of sphingomyelin from liberated sphingosine was markedly reduced. These results suggest that, in the cells used: (a) the delivery of endocytosed gangliosides to lysosomes, (b) the flow of poorly glycosylated glycolipids from the Golgi stacks to the trans-Golgi network, and (c) the direct transport of part of endocytosed gangliosides to the late sites of glycosylation (possibly TGN) are mediated by BFA-sensitive vesicles. We propose that in cultured granule cells a BFA-sensitive mechanism regulates ganglioside traffic to and from the plasma membrane.
| Original language | English |
|---|---|
| Pages (from-to) | 140-146 |
| Number of pages | 7 |
| Journal | Journal of Biochemistry |
| Volume | 116 |
| Issue number | 1 |
| Publication status | Published - 1994 |
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Keywords
- Brefeldin A
- Endocytosis
- Ganglioside metabolism
- Intracellular lipid traffic
- Neurons in culture
ASJC Scopus subject areas
- Biochemistry
Cite this
Effect of brefeldin A on ganglioside metabolism in cultured neurons : Implications for the intracellular traffic of gangliosides. / Riboni, L.; Bassi, R.; Tettamanti, G.
In: Journal of Biochemistry, Vol. 116, No. 1, 1994, p. 140-146.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Effect of brefeldin A on ganglioside metabolism in cultured neurons
T2 - Implications for the intracellular traffic of gangliosides
AU - Riboni, L.
AU - Bassi, R.
AU - Tettamanti, G.
PY - 1994
Y1 - 1994
N2 - The effect of BFA on the metabolic processing and intracellular traffic of gangliosides was studied in cerebellar granule cells, fed in culture for different periods with radiolabeled ganglioside GM1. The following results were obtained: (a) degradation of taken-up GM1 was markedly inhibited by BFA; this effect was rapid, reversible, and affected by reduced temperature, ATP depletion, and microtubule disruption: (b) direct glycosylation of internalized GM1 to GD1a was completely blocked by BFA; (c) the portion of GM1 that escaped BFA inhibition was degraded with formation of sphingosine, that was recycled for the biosynthesis of less glycosylated glycolipids (glucosyl-ceramide, GM3 and GD3); (d) in BFA-treated cells highly glycosylated gangliosides were undetectable, and the formation of sphingomyelin from liberated sphingosine was markedly reduced. These results suggest that, in the cells used: (a) the delivery of endocytosed gangliosides to lysosomes, (b) the flow of poorly glycosylated glycolipids from the Golgi stacks to the trans-Golgi network, and (c) the direct transport of part of endocytosed gangliosides to the late sites of glycosylation (possibly TGN) are mediated by BFA-sensitive vesicles. We propose that in cultured granule cells a BFA-sensitive mechanism regulates ganglioside traffic to and from the plasma membrane.
AB - The effect of BFA on the metabolic processing and intracellular traffic of gangliosides was studied in cerebellar granule cells, fed in culture for different periods with radiolabeled ganglioside GM1. The following results were obtained: (a) degradation of taken-up GM1 was markedly inhibited by BFA; this effect was rapid, reversible, and affected by reduced temperature, ATP depletion, and microtubule disruption: (b) direct glycosylation of internalized GM1 to GD1a was completely blocked by BFA; (c) the portion of GM1 that escaped BFA inhibition was degraded with formation of sphingosine, that was recycled for the biosynthesis of less glycosylated glycolipids (glucosyl-ceramide, GM3 and GD3); (d) in BFA-treated cells highly glycosylated gangliosides were undetectable, and the formation of sphingomyelin from liberated sphingosine was markedly reduced. These results suggest that, in the cells used: (a) the delivery of endocytosed gangliosides to lysosomes, (b) the flow of poorly glycosylated glycolipids from the Golgi stacks to the trans-Golgi network, and (c) the direct transport of part of endocytosed gangliosides to the late sites of glycosylation (possibly TGN) are mediated by BFA-sensitive vesicles. We propose that in cultured granule cells a BFA-sensitive mechanism regulates ganglioside traffic to and from the plasma membrane.
KW - Brefeldin A
KW - Endocytosis
KW - Ganglioside metabolism
KW - Intracellular lipid traffic
KW - Neurons in culture
UR - http://www.scopus.com/inward/record.url?scp=0027989296&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0027989296&partnerID=8YFLogxK
M3 - Article
VL - 116
SP - 140
EP - 146
JO - Journal of Biochemistry
JF - Journal of Biochemistry
SN - 0021-924X
IS - 1
ER -