Defective GM3 synthesis in Cog2 null mutant CHO cells associates to mislocalization of lactosylceramide sialyltransferase in the Golgi complex.
Neurochem Res
; 35(12): 2161-7, 2010 Dec.
Article
em En
| MEDLINE
| ID: mdl-21080064
ABSTRACT
The conserved oligomeric Golgi (COG) complex is a eight subunit (COG1 to 8) tethering complex involved in the retrograde trafficking of multiple Golgi processing proteins. Here we studied the glycolipid synthesis status in ldlC cells, a Cog2 null mutant CHO cell line. Biochemical studies revealed a block in the coupling between LacCer and GM3 synthesis, resulting in decreased levels of GM3 in these cells. Uncoupling was not attributable to decreased activity of the glycosyltransferase that uses LacCer as acceptor substrate (SialT1). Rather, immunocytochemical experiments evidenced a mislocalization of SialT1 as consequence of the lack of Cog2 in these cells. Co-immunoprecipitation experiments disclose a Cog2 mediated interaction of SialT1 with the COG complex member Cog1. Results indicate that cycling of some Golgi glycolipid glycosyltransferases depends on the participation of the COG complex and that deficiencies in COG complex subunits, by altering their traffic and localization, affect glycolipid composition.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Sialiltransferases
/
Gangliosídeo G(M3)
/
Complexo de Golgi
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Mutação
Tipo de estudo:
Risk_factors_studies
Limite:
Animals
Idioma:
En
Revista:
Neurochem Res
Ano de publicação:
2010
Tipo de documento:
Article
País de afiliação:
Argentina