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
en 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
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Sialiltransferasas
/
Gangliósido G(M3)
/
Aparato de Golgi
/
Mutación
Tipo de estudio:
Risk_factors_studies
Límite:
Animals
Idioma:
En
Revista:
Neurochem Res
Año:
2010
Tipo del documento:
Article
País de afiliación:
Argentina