O-linked N-acetylglucosamine levels in cerebellar neurons respond reciprocally to pertubations of phosphorylation.
The novel intracellular carbohydrate O-linked N-acetylglucosamine (O-GlcNAc) is present on proteins ranging from those of viruses to those of humans and include cytosolic, nuclear and plasma-membrane proteins. In this report we have examined the effect of manipulation of phosphorylation on the levels of O-GlcNAc in cerebellar neurons from early postnatal mice. Our results indicate a reciprocal response of O-GlcNAc levels to phosphorylation. Activation of protein kinase A or C, for example, results in reduced levels of O-GlcNAc specifically in the fraction of cytoskeletal and cytoskeleton-associated proteins, while inhibition of the same kinases results in increased levels of O-GlcNAc. These data are in keeping with a reciprocal action of O-GlcNAc with respect to phosphorylation and suggest that this modification may have a role in signal transduction.
Department of Biochemistry, Institute for Animal Anatomy and Physiology, University of Bonn, Germany.
L S
LS
Griffith
B
B
Schmitz
D000117:Acetylglucosamine / Q000378:metabolism*; D000818:Animals; D000001:Calcimycin / Q000494:pharmacology; D002236:Carbohydrate Conformation; D002478:Cells, Cultured; D002531:Cerebellum / Q000187:drug effects / Q000378:metabolism*; D004789:Enzyme Activation; D004791:Enzyme Inhibitors / Q000494:pharmacology; D051379:Mice; D009474:Neurons / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D010744:Phosphoric Monoester Hydrolases / Q000037:antagonists & inhibitors; D010766:Phosphorylation; D011493:Protein Kinase C / Q000037:antagonists & inhibitors / Q000378:metabolism; D020794:Receptor Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
D004791:Enzyme Inhibitors; D000001:Calcimycin; D020794:Receptor Protein-Tyrosine Kinases; D011493:Protein Kinase C; D010744:Phosphoric Monoester Hydrolases; D013755:Tetradecanoylphorbol Acetate; D000117:Acetylglucosamine