GlcNAcstatin: a Picomolar, Selective O-GlcNAcase Inhibitor That Modulates Intracellular O-GlcNAcylation Levels

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• 作者：Helge C. Dorfmueller ; Vladimir S. Borodkin ; Marianne Schimpl ; Sharon M. Shepherd ; Natalia A. Shpiro ; Daan M. F. van Aalten
• 刊名：Journal of the American Chemical Society
• 出版年：2006
• 出版时间：December 27, 2006
• 年：2006
• 卷：128
• 期：51
• 页码：16484 - 16485
• 全文大小：160K
• 年卷期：v.128,no.51(December 27, 2006)
• ISSN：1520-5126

文摘

Many phosphorylation signal transduction pathways in the eukaryotic cell are modulated by posttranslational modification of specific serines/threonines with N-acetylglucosamine (O-GlcNAc). Levels of O-GlcNAc on key proteins regulate biological processes as diverse as the cell cycle, insulin signaling, and protein degradation. The two enzymes involved in this dynamic and abundant modification are the O-GlcNAc transferase and O-GlcNAcase. Structural data have recently revealed that the O-GlcNAcase possesses an active site with significant structural similarity to that of the human lysosomal hexosaminidases HexA/HexB. PUGNAc, an O-GlcNAcase inhibitor widely used to raise levels of O-GlcNAc in human cell lines, also inhibits these hexosaminidases. Here, we have exploited recent structural information of an O-GlcNAcase-PUGNAc complex to design and synthesize a glucoimidazole-based inhibitor, GlcNAcstatin, which is a 5 pM competitive inhibitor of enzymes of the O-GlcNAcase family, shows 100000-fold selectivity over HexA/B, and binds to the O-GlcNAcase active site by mimicking the transition state as revealed by X-ray crystallography. This compound is able to raise O-GlcNAc levels in human HEK 293 and SH-SY5Y neuroblastoma cell lines and thus provides a novel, potent tool for the study of the role of O-GlcNAc in intracellular signal transduction pathways.