Role of protein glycosylation on the expression of muscarinic receptors of N4TG1 neuroblastoma cells

Conference · Thu May 01 04:00:00 EDT 1986 · Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States)

OSTI ID:5097512

Ahmad, A; Chiang, P K

Muscarinic acetylcholine receptors (mAChR) are glycoproteins. Experiments were conducted to determine whether active glycosylation of proteins in N4TG1 neuroblastoma cells could affect the expression of muscarinic receptors on the cell surface. The binding of radioactive N-methylscopolamine, a membrane impermeable ligand, to intact cells was used as a measure of mAChR. In the presence of the inhibitors of glycosylation, such as tunicamycin, monensin and amphomycin, N-linked glycosylation of proteins in the N4TG1 cells was inhibited, as measured by the incorporation of radioactive glucosamine or mannose in proteins. At the concentrations of tunicamycin and monensin used, the glycosylation of proteins after 3 hours were drastically reduced, but the number of mAChR in the cells was not altered. The apparent lack of effect within a short incubation period could be attributed to the presence of preformed oligosaccharide dolichol readily available for N-glycosylation. However, after 24 hours, tunicamycin (0.05 ..mu..g/ml) caused a decrease in the number of mAChR by 17% without having any effect on protein synthesis. Therefore, de novo glycosylation of proteins may be required for the expression of mAChR receptors in the N4TG1 neuroblastoma cell surface.

• Research Organization: Walter Reed Army Institute of Research, Washington, DC
• OSTI ID: 5097512
• Report Number(s): CONF-8606151-
• Conference Information: Journal Name: Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States) Journal Volume: 45:6
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ACETYLCHOLINE
AMINES
AMMONIUM COMPOUNDS
ANIMAL CELLS
AUTONOMIC NERVOUS SYSTEM AGENTS
BIOCHEMICAL REACTION KINETICS
CARBOHYDRATES
DRUGS
ESTERS
GLUCOPROTEINS
GLUCOSAMINE
GLYCOLYSIS
HEXOSAMINES
HEXOSES
ISOTOPE APPLICATIONS
ISOTOPES
KINETICS
MEMBRANE PROTEINS
METABOLISM
MONOSACCHARIDES
NEUROREGULATORS
ORGANIC COMPOUNDS
PARASYMPATHOMIMETICS
PROTEINS
QUATERNARY COMPOUNDS
RADIOISOTOPES
REACTION KINETICS
RECEPTORS
SACCHARIDES
TRACER TECHNIQUES
TUMOR CELLS