Biosynthesis of a low-molecular-mass rat submandibular gland mucin glycoprotein in COS7 cells.
Biochem J
; 323 ( Pt 2): 497-502, 1997 Apr 15.
Article
en En
| MEDLINE
| ID: mdl-9163344
ABSTRACT
We have examined the biosynthesis of a low-molecular-mass mucin from rat submandibular gland (RSMG) expressed recombinantly in COS7 tissue culture cells, focusing primarily on the addition of carbohydrate to the protein core of the mucin. We find evidence for N-linked glycosylation, but this modification is not required for secretion of the mucin. Similarly, although the recombinant RSMG mucin, like its native counterpart, contains large amounts of O-linked carbohydrate, chain extension beyond the initial O-linked GalNAc moiety is not required for secretion. We have identified partially glycosylated mucin by a combination of metabolic pulse-chase and lectin precipitations of the biosynthetic intermediates. Our results suggest that the addition of GalNAc to threonine and serine in the RSMG mucin does not occur simultaneously, as has been described for other O-glycosylated proteins.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Glándula Submandibular
/
Mucinas
Límite:
Animals
Idioma:
En
Revista:
Biochem J
Año:
1997
Tipo del documento:
Article
País de afiliación:
Estados Unidos