Genome-scale identification of UDP-GlcNAc-dependent pathways.
Metabolite flux to UDP-GlcNAc and Golgi N-glycan biosynthesis regulates surface residency of glycoprotein receptors and transporters, and thus sensitivities of cells to extracellular cues. Salvage of GlcNAc increases UDP-GlcNAc and branching of N-glycans progressively, but displays an optimum for cell proliferation and bulk endocytosis in mouse NMuMG and human HEK293T epithelial cells. In this report, we measured global changes in gene expression in low and high GlcNAc-supplemented cells. Genes upregulated by high GlcNAc included the EGF and TGF-beta signaling pathways and cell cycle checkpoint, while downregulated genes indicated lower metabolic activity. Genes increased or decreased by high GlcNAc were assessed by transfecting cells with small interfering RNA (siRNA) and measuring effects on three phenotypes: proliferation and bulk endocytosis, and beta1,6GlcNAc-branching of N-glycans. siRNA targeting LGALS3, WBSCR17, PHF3, SDC2 and CTNNAL1 partially reversed the GlcNAc-induced phenotypes, suggesting a role for galectin-3/N-glycans, proteoglycans, O-glycans, and junctional cell adhesion.
Lau
Ken S
KS
Samuel Lunenfeld Research Institute, Mount Sinai Hospital, ON, Canada.
Khan
Sofia
S
Dennis
James W
JW
D000818:Animals; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects; D002851:Chromatography, High Pressure Liquid; D004705:Endocytosis / Q000187:drug effects; D020869:Gene Expression Profiling; D015894:Genome, Human / Q000235:genetics*; D006801:Humans; D020411:Oligonucleotide Array Sequence Analysis; D034741:RNA, Small Interfering / Q000235:genetics; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology*; D014537:Uridine Diphosphate N-Acetylglucosamine / Q000378:metabolism* / Q000494:pharmacology
D034741:RNA, Small Interfering; D014537:Uridine Diphosphate N-Acetylglucosamine