Fatty acid acylation of salivary mucin in rat submandibular glands
The acylation of salivary mucin with fatty acids and its biosynthesis was investigated by incubating rat submandibular salivary gland cells with (/sup 3/H)palmitic acid and (/sup 3/H)proline. The elaborated extracellular and intracellular mucus glycoproteins following delipidation, Bio-Gel P-100 chromatography, and CsCl equilibrium density gradient centrifugation were analyzed for the distribution of the labeled tracers. The incorporation of both markers into mucus glycoprotein increased steadily with time up to 4 h, at which time about 65% of (/sup 3/H)palmitate and (/sup 3/H)proline were found in the extracellular glycoprotein and 35% in the intracellular glycoprotein. The incorporation ratio of proline/palmitate, while showing an increase with incubation time in the extracellular glycoprotein, remained essentially unchanged with time in the intracellular glycoprotein and at 4 h reached respective values of 0.14 and 1.12. The fact that the proline/palmitate incorporation ratio in the intracellular glycoprotein at 1 h of incubation was 22 times higher than in the extracellular and 8 times higher after 4 h suggests that acylation occurs intracellularly and that fatty acids are added after apomucin polypeptide synthesis. As the incorporation of palmitate within the intracellular mucin was greater in the mucus glycoprotein subunit, it would appear that fatty acid acylation of mucin subunits preceeds their assembly into the mucus glycoprotein polymer.
- Research Organization:
- New York Medical College, Valhalla
- OSTI ID:
- 6138577
- Journal Information:
- Arch. Biochem. Biophys.; (United States), Vol. 2
- Country of Publication:
- United States
- Language:
- English
Similar Records
Majority of cellular fatty acid acylated proteins are localized to the cytoplasmic surface of the plasma membrane
Studies on the attachment of fatty acid and N-acetylgalactosamine to mucus glycoprotein nascent chains in rat gastric mucosa
Related Subjects
HEXADECANOIC ACID
ACYLATION
PROLINE
SALIVARY GLANDS
BIOCHEMISTRY
TRITIUM COMPOUNDS
CARBOHYDRATES
GLUCOPROTEINS
MUCOUS MEMBRANES
RATS
AMINES
AMINO ACIDS
ANIMALS
AZOLES
BODY
CARBOXYLIC ACIDS
CHEMICAL REACTIONS
CHEMISTRY
GLANDS
HETEROCYCLIC ACIDS
HETEROCYCLIC COMPOUNDS
LABELLED COMPOUNDS
MAMMALS
MEMBRANES
MONOCARBOXYLIC ACIDS
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANS
PROTEINS
PYRROLES
PYRROLIDINES
RODENTS
SACCHARIDES
VERTEBRATES
550201* - Biochemistry- Tracer Techniques