Title : N-linked glycosylation is required for plasma membrane localization of D5, but not
D1 , dopamine
receptors in transfected mammalian cells
Abstract :
- We have analyzed the role of N-linked glycosylation in functional cell surface expression of the D1 and D5 dopamine receptor subtypes
- Treatment of transfected HEK 293 cells with tunicamycin , an inhibitor of N-linked oligosaccharide addition, was found to prevent localization of D5 receptors in the plasma membrane
- In contrast, tunicamycin treatment had no effect on the plasma membrane localization of the D1 receptor
- Polymerase chain reaction mutagenesis was used to generate a panel of D5 receptors containing mutations in the three predicted sites of N-linked glycosylation
- Expression of mutant receptors indicated that glycosylation of residue N7 was the major determinant of D5 receptor plasma membrane localization
- Mutation of a comparable site in the D1 receptor at position N5 had no effect on the delivery of the D1 receptor to the cell surface
- Tunicamycin treatment during receptor biosynthesis, but not N-glycosidase F digestion of mature receptors , abrogated binding of the D5 receptor antagonist [(3)H]SCH23390, suggesting that while oligosaccharide moieties play a key role in the cell surface expression of D5 receptors , they do not appear to contribute to the receptor 's ligand binding properties
- Together, our data indicate a differential requirement for N-linked glycosylation in functional cell surface expression of D1 and D5 dopamine receptors
Output (sent_index, trigger,
protein,
sugar,
site):
- 0. glycosylation, , D1, -, -
- 0. glycosylation, , receptors, -, -
- 4. glycosylation, , -, -, sites
Output(Part-Of) (sent_index,
protein,
site):
*Output_Site_Fusion* (sent_index,
protein,
sugar,
site):