Phosphofructokinase 1 Glycosylation Regulates Cell Growth and Metabolism

Metabolic Sensor The enzyme O-GlcNAc transferase (OGT) catalyzes the transfer of N -acetylglucosamine from uridine diphospho- N -acetylglucosamine (UDP-GlcNAc) to serine or threonine residues of intracellular proteins and responds to the metabolic status of the cell. Yi et al. (p. 975 ; see the Perspective by Mattaini and Vander Heiden ) show that O-GlcNAcylation of phosphofructokinase 1 (PFK1) reduces its activity, thus influencing rates of glycolysis within cells. O-GlcNAcylation of PFK1 was increased in cells exposed to hypoxia, and was increased in several cell lines derived from human tumors. Thus, metabolic changes mediated by O-GlcNAcylation may benefit anabolism and growth of cancer cells. However, glycosylation of PFK1 was not detected in rapidly proliferating normal cells.